(GE) Magne Blast Breakers 5k V Vol 1 Of 3

2018-02-16

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GEMGBLST.XLS

i.E. - MAGNE-BLAST BREAKERS AND SWITCHGEAR (Volume 1 of 3)

Instruction Book

AM-4.16-75, 75A, 75H-1

GEI-77070A

Instruction Book and Renewal Parts

with MS-9 Mechanism

GEI-77070

instruction Book and Renewal Parts

GEH-2000A

Instruction Book and Renewal Parts

GEI-77070B

AM-2.4/4.16-100/150-3
AM-2.4/4.16-100/150A-3
AM-2.4/4.16-150/250-3
AM-2.4/4.16-150/250A-3
With MS-13 Mechanisms

GEH-1804D

Instruction Book and Renewal Parts

Same but -1 & -2 Breakers

GEH-2000F

Instruction Book and Renewal Parts

AM-4.16-150-3
AM-4.16-150A-3

AM-4.16-250-3
AM4.16-250A-3

With MS-13 Mechanisms

GEH-2054C

Instruction Book and Renewal Parts

AM-4.16-150A-4&4S

AM-4.16-250A-4 & 4S

GEH-2054A

AM-4.16-150H-4&4ML

AM-4.16-150H-4S&4SML
AM-4.16-250H-4&4ML
AM-4.16-250H-4S & 4SML

With ML-11 & MS-13 Operating Mechanism:

GEI-88761E

Instruction Book and Renewal Parts

AM-4.16-250-6C
AM-4.16-250-6H

AM-4.16-250-7C
AM-4.16-250-7H

GEK-41902C

Instruction Book and Renewal Parts

AM-4.16-250-9 1200 & 2000A
with ML-13 Mechanism

Page 1

GEMGBLST.XLS

GEI-88762A

Instruction Book and Renewal Parts

AM-4.16-350-1C
AM-4.16-350-1H

GEK-7320F

Instruction Book and Renewal Parts

AM-4.16-350-2C
AM-4.16-350-2H

GEI-88771D

Instruction Book

AMH-4.76-250-1D

GEI-88771A

GEi-23903C

AMH-4.76-250-OD

Instruction Book

AM-5-50-4
AM-5-50-5

With MS-9 & MS-9-1 Mechanisms

GEI-13532D

Instruction Book

AM-5-100
AM-5-150

GEF-3486B

Renewal Parts

AM-5-150

GEI-50143F

Instructions & Renewal Parts

.11,11A, 11B. lie, 11D Stored Energy Me

GEI-50143A

Instructions & Renewal Parts

ML11,11 A, 11B Stored Energy Mech

GEF-4379A

Renewal Parts

ML-13 Mechanism

NOTE: SIL/SAL Information is in Vol. 3 of 3 @ the back (last tab)

Page 2

-.
INSTRUCTIONS

GEI-77070 B
SUP£RSEOt5

MAGNE - BLAST
CIRCUIT BREAKERS
Types
AM 4.16 • 15 · 1
AM 4.16·75A·1
AM 4.16·7SH· 1.
with
MS -9 Mechanism
CONTENTS

•

INTRODUCTION .................... 3
RECEIVING, HANOLlNG
ANO STORAGE ................ 3
lNSTALLATION..................... 3
DESCRIPTION OF
OPERATl01' ................... 4
ADJUSTMENTS ..................... 4
INSPECTION AND TEST ......... 9
MAINTENANCE ................... 10
RENEWAL PARTS.••.••••..•••••• 17

GENERALfj ELECTRIC

GEi -77070A

MAGNE-BLAST
TYPES

CIRCUIT

4.16-75-1

WITH

MS-9

AND

BREAKER
AM

4.16-75A-1

MECHANISM

INTRODUCTION
The Magno-blaat Ctrciiit Breaker ie
the removable Interrupting element for use
In vertlcal*lUt metal-clad swltchgear, to

provide reliable control and protectton of
power systema.
The Magne-blast Circuit Breaker oper
ates on the principle that an arc can be
Interrupted in air t>y sufficiently elongating
and cooling it. This u accomplished by
means of a strong magnetic field that

lengthens the arc and forces it Into Intimate
contact with cool dielectric material.

Refer to the breaker nameplate for the

design, all instructions will be of a general
character and all illustrations will be typi
cal, unless otherwise specified,

complete rating information of any parti
cular breaker. The short circuit conditions

to be imposed on the breaker must not ex
ceed Its rating, nor should It be called upon
to operate at voltages or currents greater
than those given on the nameplate. Since
this book is written to cover several ratings
of breakers that are of the same general

PROPER INSTALLATION AND MAIN
TENANCE ARE NECESSARY TO INSURE
CONTINUED SATISFACTORY OPERATION

OF THE BREAKER. The following instruc
tions will provide information for placing
the raagne-blast breaker in service and for
maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
S
§

RECEIVmG AND HANDLINC

Each breaker is carefully inspected
and packed by workmen experienced in the

proper handling and packing of electrical

>
"

equipment. Immediately upon receipt of
the circuit breaker, an examination should
be made for any damage sustained in tran

sit. If Injury or rough handling is evident,
a damage claim should be filed immediately

with the transportation company and the

breaker. Loose parts associated with the
breaker are always Included In the same

are In operation to prevent condensation.

crate. Check all parts against the packing
list to be sure that no parts have been

2. The breaker should be stored tn a clean

to protect the equipment from moisture
STORAGE
It is recommended that the breaker be

put Into service Immediately in its per
manent location. If this is not possible,

nearest General Electric Sales Ofiice should
bs notified.

the following precautions must be taken to
Insure the proper storage of the breaker;

It Is expected that due care will be ex
ercised during the unpackingand instaUation

1. The breaker should be carefully pro
tected against condensation, preferably
by storing it in a warm dry room, since
water absorption has an adverse effect
on the Insulation parts. Circuit breakers
for
outdoor metal-clad switchgear

of the breaker so that no damage will occur
from careless or rough handling, or from
exposure to moisture or dirt. A nailpuller
should be used to open the crates, and care

should bs exorcised to prevent tools from
striking either the crate or any part of the

location, free from corrosive ^es or

fumes; particular care should be taken

overlooked.

should be stored tn the equipment only
when power is available and the heaters

and cement dust, as this combination
lias a very corrosive effect on many
parts.

3. Machined parts of the operating mecha
nism, etc., should be coated with a heavy
oil or grease to prevent rusting.

If the breaker is stored for any length
of time, it should be inspected periodically
to see that rusting has not started and to
Insure good mechanical condition.

Should

the breaker be stored under unfavorable

atmospheric conditions, steps should be
taken to dry out the breaker before It is
placed in service.

INSTALLATION
Remove liox liarrler and make a visual

inspection to ascertain that the breaker is

trically until It has been operated manually

Remove test coupler and replace box

to Insure this freedom of action.

Inrrler.

The following adjustments should be
checked at this point.

If breaker has been stored lor a long
period of time, it Is recommended that the

in sattsfactory condition. Checkalll)caring
surfaces of the mechanism for lubrication.
Refer to the section on LUBRICATION

(page 11).
a. Primary contact wipe (page 5).

Operate breaker manually using the
maintenance closing device provided with
the breaker. During the closing operation,

b. Primary contact gap (page S).
c. Prop clearance (page S).

check to Insure that the mechanism and

breaker does not stick or bind during the

entire stroke, that it latches securely in
the closed position, and that it trips freely
when the manual trip plunger is operated.
The breaker should not be operated elec

insulation

t>e checked with the standard

60 cycle high rwtential test — see INSULA
TION TEST &age 11).
Lubricate the silver portion of the
primary disconnect studs by rubbing a
small amount of contact lubricant DS0H47 to

Attach test coupler to circuit breaker
and operate electrically several times.
The control voltage should be checked at
the breaker as indicated under CONTROL

POWER CHECK (page 10).

form a thin coating on the ball contact.
Refer to instructton book GEH-1802

for final instructions before Inserting the
breaker into the metal-clad untt.

riwso Instmctlons do noc purport Co covox alX docoiJs or varrueions in oyuipnent nor to provida /or
ovesv possible contingency to be jnat in cannsction nith installation, operation or aeintenance.
Sbouid
further inforaation be desired or should partioular problons arise uhich are not covered su//ieientiy for
tiia purchaser's purposes, the matter should be referred to the deneral Sloocric Coapany.
To the ostent required the preducte deaoribed herein poet applicable AlfSl, ISES and NEHA standards/
bat no aueh assurance is given uith respect to local codas and ordinances because they vary greatly.

OEI-TT070 Magne-blaet Clreutt Breaker Typa AM 4.ie-76

DESCRIPTION OF OPERATION

The raagne-blast breaker la composed

gizing the trip coll, the trip plunger rotates

device. Figs. S and 6 mounted on the

and 8. The breaker element comprises three
similar pole units, each pole umt consisting
ol main and arcing contacts, an interrupter,
and an encloslngbmbarrier thatsegregates
the Interrupting units from each other to

In the opening spring Is thus released, open
ing the breaker. During this i^eratton, the
trip coU circuit Is de-energlzed, and upon
completion of the opening operation, the

a remote operating station. Opsratlon
of the closing control switch energizes the

operating mechanism Is returned to its

provide Insulation between phases as well

normal position, ready for closing.

of two mi^or parts, the breaker elemeot
Fig. B and the operating mechanism Figs.?

as from each phase to ground. Theprlmary
connections to the associated metal-clad

equipment are made through the primary

Qte trip latch, causing the operating mecha
nism linkage to collapse. The energy stored

As the breaker opens, the main con
tacts part first, shunting the current

disconnect studs.

through the arcing contacts. An arc forms

The Md-9 operating mechanism shown
In Fig. 7 Is of the solenoid type designed

arcing contact Is wfthdrawn through the

as the arcing contacts part. As the movable

to give high speed closing and opening.
The closing operation Is controlled by
the control relay. The control relay scheme

permits trip-free operation (tripping the
ttreaker at any time during the closing

operation), and prevents solenoid pumping

(reclosinu after a trip-free operation. For
a-c closing operation, rectifiers mounted
elsewhere in the metal-clad unit are used

to supply the direct current on which the
closing coll (merates. The breaker can be
opened electrically, by remote control, or
manually, by means of the manual trip
device.

All secondary connections from

the breaker to the metal-clad unit are

made thtou^ the coupler.

A positive Interlock and Interlock switch
Is provided between the breaker and metalclad unit to prevent the raising or lowering

arc Is transferred to the upper arc runner.
To assist the biterruptlon at this point, a
stream of air Is emitted from the booster
tube and forces the arc onto the lower arc
runner. Establishment of the arc on the

the arc Is absorbed.

position. During the closing operation, the
opening spring is compressed In readiness
for an opening operation. Air trapped above
the armature acts as a dash pot to absorb

ually deepening serpentine path, so that the
electrical resistance In the path of the
arc is rapidly Increased and the heat from
The increased re

sistance reduces both the magnitude and

cooled that the arc cannot re-establish

the trip circuit, the manual trip button Is
used.

closing coll

raises the armature which

in turn lifts the closing roller by action

breaker contacts. As the armature reaches

the

energy

the mechanism as It

approaches the end of its stroke.
TRIP FREE OPERATION
REFER TO FIG. 8

If the trip coll circuit Is energized
while the breaker is closing, the trip
plunger will force the trip latch away

CLOSING OPERATION

from the trip roller causing the mech
anism linkage to trip free and the breaker
to re-open. The closing armature com

REFER TO FIGS. 8 & 9

pletes Its closing stroke, but the closing

An electrical opening operation Is In

By ener

Once

Ihey are electrically held In the closed

the end of its travel, the prop rotates bsneath
the pin latching the breaker In the closed

REFER TO FIGS. 8 ft 9

the Irad side of the breaker.

the main control relay contacts.

the control relay contacts are picked up.

of the chute, elongate the arc Into a grad

series of gradually Interleaving Insulating
fins.
These fins, which project alter
nately from the two opposite Inner surfaces

Manual tripping follows the same pro
cedure except that Instead of energizing

current devices used to delect a fault on

Operation of the control relay ener

gizes the breaker closing cotl by closing

the arc chute which Is composed of a

OPENDtO OPERATION

opening control switch on the metal-clad
unit or by a combination ol relays and

switch.

of the solenoid plunger rod. This motion
is transmitted through the mechanism link
age and robttes the main crank closing the

Itself, and Interruption occurs.

itiated by energizing the trip coll. This
Is accomplished either by actuating the

control relay closes, seal-in conbcts shunt
the closing control switch to allow the open
ing of the closing control switch contacts
without affecting the overall closing opera
tion.
This type of arrangement assuree
complete closing of the breaker with only
momentary contact of the closing control

position until the breaker closing opsra
tlon Is completed. Energizing the breaker

Interlock can also be provided.

raised or lowered position. A plunger type

pick-up coils of the control relay. As the

runners automatically Inserts the blowout
coll Into the circuit, Introducing amagnellc

field between the pole pieces which tends to
draw the arc away fromthearclngcontacts.
At theaametlme,thearclebelngforced Into

when the breaker Is not In either the fully

position and to prevent a closing operation

on the door u/t

6- Switch Mounting Sreeket
7. Interlock indexing Roller

The roller and crank on the inleriock switch

should have 1/32" to 1/18" overtravel after
final adjustment.
CUT-OFF SWITCH ADJUSTMENT

REFER TO FIGS. S AND 5A

Using a manual closing handle, close

the breaker as far as possible. (So that
the prop pin is over thspropandnot resting
on the prop). At this point the "S" shaped
striker rod should be resting aralnat the

striker rod guide bracket (3), ng. & as
ehowo In Fig. 5A.

Adjust cut-off switch striker rod (2),

Fig. 5 so that it Is against the switch roller
(7), Fig. S and so that the awttch roller has

Fig. 4

PoAltWe Interlock Switch

an additional overtravel of 1/32".
CONTROL RELAY ADJUSTMENT
REFER TO FIGS. 6 AND 8
TYPE HJA REIAY

The relays have been adjusted at the
factory to nick up at 61 per cent of rating
for d-C relays and 60 per cent for a-c

relays. The settings of the various contact
gaps and wipes should not be dtsturbeo.
U tt is necessary to readjust the relays

the following points should be observed.
Tbe wipe of the main contacts should be

1/8" measured at the top edge of the pole

1. cut-off Switch

piece while that of the auxiliary should be
1/9" when measured at the rear edge of the

2. Cut-off Soiteh Striker Rod

armature stops.

3. Striker Bod Ouide Sreeket

If the setting ol the controlsprtngmust
be changed for any reason, care must be

fi. Control Reley Mounting Mete

4. Striker (ted Adjuttnent Kut
5. Control Beley (ilJA Krley)

taken during the readjustment to see that the
control spring Is not weakened (o tbe point
of permitting the minimum of wipe to exist
at (he normally closed auxiliary interlock
contacts.

The relay contains a permanent mag
net which has numbers stamped on one end
only. The magnet is oriented properly in
the relay when 11 ts posttloned so tliat the
numbers arc located on the left hand side,

(Facing relay.)

(is .j. rlliiika

On d-c operated relays, avlslblecheck

should be made to see that the arc being

tnterrupted by the relay te directed throu^
the arc chute and not back over the relay

Fig. 5

Side Vleo of Costrol Relay and Cut-off Switch A.Mably

Magne-blaal Circuit Breaker Type AM 4.16-75 GEI-77070

INSPECTION
For ease In revle«lnB the adiustments
the following are recapitulated:

a. Primary contact wipe:
1/8"+ 1/16" • 0.
*

AND

TEST

breaker when the control voltage drops

below 40 to 60% of rated voltage, and

It should ptck-up at 80% of the control
voltage or less.

An adjustment plate Is

provided on the front of the undervollage
trip device as an aid In obtaining the

b. Arcing conbctwipe: 7/32" to 9/32".

desired setting.

c. Primary contact gap:
4-1/6" to 4-1/4".

NOTE: When checking the pick-up value
of the undervollage device, apply a voltage

d. Trip latch wipe: 1/8" to 1/4".

the undervollage device coll. The device
should pick up at this value. Do not In
crease the voltage gradually on this coll
as It will overheat the coll, producing a

e. Prop clearance;

1/32" to 3/32"

with a maximum variance of 1/32".

false reading, and may damage the col)
If excessive overheating occurs.

equal to 80% of normal control voltage to

OPENING AND CLOSING SPEED

The closing speed of the arcing con
tact should be 12 to 16 feet per second
with rated closed circuit voltage at the
closing coU terminals.
These speeds

represent the average speed of the movable
arcing contact from a point 1" before the
tip Is tangent to the lower surface of the
upper arc runner transfer lugs to the
tangent position.

f. Trip latch clearance:

1/32" to 1/16"

g. Solenoidplunger clearance:

1/8" or greater.

h. Impact trip wipe: 1/32" to 1/16".

J. Impact cam latchclearance: 1/16".
k. hiterlock swlteh:

1/32" to 1/16"

overtravel.

I. Cut-off switch overtravel;

1/32" to 1/16".
m.

Plunger Interlock:
5-1/8" + 1/16" - 0.

Check all nuts, bolts, screws, and

riD

cotter pins to make certain that they are
properly tightened.
Inspect all wiring. Check all terminals,
screws, and connections and test the cir
cuits lor possible short circuits or grounds.
See that all bearing surfaces of the
mechanism have been lubricated. Refer to
the section on LUBRICATION.

Operate the breaker slowly with the
maintenance closing handle and note that
there is no excessive binding or friction
and that the breaker can be moved to the

fully opened and folly closed positions.
See that any place where the surface
of the paint has been damaged is repainted

imm^iately.

Check the operating voltage for both
the closing coll and trip coll to determine
If, with line drop, it Is within the limits
specified on the nameplate. In the case
of a rectifier cjperated mechanism, the
d-c voltage across the coll terminals with

full closing coll current flowing should be
105-110 volts. (For applications of repeti
tive operations, the d-e voltage across the

closing coll should not exceed 110 volts.)
Refer to section on CONTROL POWER
CHECK.
AUXILIARY DEVICES

1. Front Buihing
3. Horizontal Borrter
3. Trip Coil
4.

On breakers that are equipped with
auxiliary devices such as current trip,
undervollage trip or capacitor trip, the
device should be checked for proper elec
trical operation. The current trip device
should trip the breaker at 3 amperes.

The undervollage device should trip the

Operating Kochanisa

S. Front Vortieoi Barrier
6.

Arc Chute Aseeubiy
Rear Bushing

Fig. 9

8. Box Barrier
9. Breaker Frame

Box Barrier Locking Fiat*
Piimger Interlock
Secfxidary Coupier
13. Uonuol Trip Button
14. Ciosing Coll
IS. Are Chute Ucuiting Support
10.
u.
13.

3lds View AII-e.l6-7S-t Breaker with H5-9 Heclianlen

Magne-blast Ctrcuit Breaker Type AM 4.16-75

GEI-77070

> r-

ricant D50H47. It is not necessary
to grease the self-lubricating con
tact ring at the hinge point between
the contact blade and bushing. The

contact ring should be Inspected for
wear and replaced when reduced in

thickness to less than 1/32".
4. The stationary primary contact fin
gers should be disassembled and the
silver-plated pivot area of the con
tact and contact support cleaned
and lubricated with G-E lubricant

1. IfechanisB Frane

2. Linkage
3. Latch Qiecklng Switch
4. Shins

Fig. II

D50H47.

Utcb Checking SmUcIi

nism should be serviced as described

present a possibUl^ el fin sections

lor every 2,000 operations and
properly adjusted before being put

breaking

back Into service.

off.

Small

The primary contacts are designed to
carry the normal load current with a
minimum amount of heating and arc pro
vided with an Inlaid block of sliver to
rolnimtae tbe effects of wear. The station

ary primary contacts consist of 4 fingers
for

the

1200 ampere breaker and are

mounted along with Uie associated springs
on the support casting carried by the rear
pushing.
The fingers may be replaced

REPAIR AND REPLACEMENT

be disregarded.

The following information covers in

C. Every 20.000 Operations or Approxi
mately Every Five Years - Whichever
Comes First
1. At this time the breaker should be

given a general overhaul and all
excessively worn parts fai l»th the
mechanism and breaker replaced.
Such wear will usually be indicated
when the breaker cannot be adjusted
to instruction book tolerances. This

detail

the

proper

method of removing

various parts of the breaker in order to
make any necessary repairs. This section
includes only those repairs that can he
made at the installation on parts of the
breakers that are most subject to damage

REFER TO FIG. 6

is carried on the blade hinged at the Trent
Inishtng. The arc chute must be removed
(see section ARC CHUTE REMOVAL) and
the foUowbig steps should be followed for
replacement of the contact blade;-

o r wear.

(a) Remove the bolt fastening the arc
chute supporting the bracket to the

lower end of the front bushing, and
remove the bracket.

(b) Dtsconnect the puffer tube and op
IMPORTANT:

UPON

COMPLETION OF

ANY REPAIR WORK, ALL BREAKER AND
MECHANISM ADJUSTMENTS MUST BE
CHECKED.
Refer to the section on AD

overhaul and Inspection is more de
tailed and will require disassembly

JUSTMENTS, INSPECTION AND TEST.

parts.

Before maintenance or replacement of
contacts, the arc cimtes must be removed.

of mechanism and breaker operating

pivot end.

The movable pr1maryeotttact(7), Flg,6

broken corners on the exhaust end
of the arc chute will not interfere

with its performance and can also

REFER TO FIG. 1

alter removing the cotter pin through the
5. The breaker and operating mecha

heat of an arc and may be disre
garded unless they are long and
completely

PRIMARY CONTACTS

erating rod from the contact blade.

(d) Slip the contact blade off the end
of the tnishtng and withdraw.

t. current Trip Itait

2. Trip Shaft
3. com Latch

4. Breaker Trip Latch
5. Latch Bradcet
6. Ouide

7. Spring
8. Crank

9. Spacer Block
10. Leek Kut

11. Adjustable Bod
12. Pin
13. Loeknut

14. Adiosting Serov

Fig. 12

13 14

Current Trip Asseably HS-9 Solenoid HaehanlaB
13

0£i-77070 Magn^'bl^t Circuit Breaicer Type A1E1 4.16-70

Magne-blast Ctrcult Breaker Type AM 4.16-16 GEI-71070

Reassemble the replacement parts
making certain that all cotter pins are

replaced.

U a new hinge tmlt has been

usM, or tl It seems desirable for any

other reason, the pressure at the hinge

joint should be checked by measuring with
a

Bprlng balance the (orce required to

swing the contact arm. For both the 60D
and 1200 ampere breakers, this (orce
should be between 40 and 60 pound-inches.

(e) Insert spring through the top of
the bracket, spring block and Into
the spring cup.

holding the solenoid pot assembly together.
Slide cover (5), closing coil(16) Fig. 6, and
armature and plunger assembly (17) and
(18), Fig. 8 out. To assemble, reverse

(f) Place the assembly on the under
side of the bushing, and engage the
cap screws one turn In the spring
guide block.

the above procedure.

(g) Insert the arctng contact springs

coil

and guide.
ARCINO CONTACTS

(h) Tighten the cap screws, and re
assemble the stop bolt and lock

REFER TO FIG. 1 AND 3

replace, the (ollowing steps

followed:

(a) Remove lock nut and stop bolt.

the arcing finger.

CLOSING COIL
REFER TO FIG. 19

To replace the closing coll turn the
breaker over on its liack. Remove the wheel

(d) Place pivot spring guide block in

(NOTE; The letters

relation to the physical position of the

The contacts should l>c adjusted as
described previously under ADJUSTMENTS.

should be

(b) Place arcing finger on pivot pin.
(c) Place fibre spring cup on top of

wire tap,

"T" and "B" designate top and bottom in

Fig. 1) is carried by the bracket iastened

screws from the top (not shown).

lead (designated wtth a

lettered "B") to the HJA relav terminal
93 and connect the top coil lead (designated
with a wire tap, lettered "T") to the HJA

relay terminal #1.

nut.

The stationary arcing contact (see
to the lower side of the rear bushing. To
remove, take out the two Allen head cap

When making the final connection of

the closing coil wires be careful on d-c
operated breakers to connect the bottom

base by removing eight bolts (1) holding

position on the underside of the

it to the frame.

top of the bracket.

leads (13) Fig. 7.

Disconnect closing coil

Remove four nuts (4)

closing coU as it is assembled in the

mechanism on the breaker.) A final check
should be made to see if the connection
ts made accurately.
After the breaker

adjustments have been made, and the
breaker manually operated a few times,

operate It electrically and observe the
direction of the arc on the control relay (S)

Fig. 5.

If It is directed through the arc

chute the connection is made correctly.
If the arc Is directed tcrward the relay coil,
a careful check for other trouble should

be made by going over the rheck list as
described under HJA CONTROL RELAY
ADJUSTMENT.

Magne-blaat Circuit Breaker Type AM 4.10-16

GEI-7T010

RENEWAL PARTS
It Is recommended that suHiclent re

newal parts be carried in stock to enable
the prompt replacement of any worn, broken

or damaged parts. A stock of such parts

be carried, the amount depending upon the

minimizes service Interruptions caused by
breakdowns, and saves time and expense.
When continuous operation Is a primary
consideration, more renewal parts should

severity of the aervlceand the time required
to secure replacements.

HOTE: The listed terms "right" and "left" apply when facing the solenoid mechanism end of the breaker.
OROERINa INSTRUCTIONS

1. ALWAYS SPECIFY TRE COMPLETE NAMEPLATE DATA OF BOTH THE BREAKER AND THE
MECHANISM.

2. SPECIFY THE QUANTITY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF LISTED),
AND DESCRIPTION OF EACH PART ORDERED, AND THIS BULLETIN NUMBER.

3. STANDARD HARDWARE, SUCH AS SCREWS, BOLTS, NUTS, WASHERS, ETC., IS NOT LISTED IN THIS
BULLETIN. SUCH ITEMS SHOULD BE PURCHASED LOCALLY.

4. FOR PRICES, REFER TO THE NEARES OFFICE OF THE GENERAL ELECTRIC COMPANY.
ILLUSTRATION REFERENCE
PAGE

Cross-sections - Type AM 4.16-7S-1

Fig. 16

Front Bushing Assembly

Fig. 17

Rear Bushing Assembly

Fig. 18

Arc Chute

Fig. 19

MS-9 Mechanism (or AM 4.16-76-1

Fig. 20

Current Trip Mechanism

Fig. 21

Undervollage Device, Cover Removed

Fig. 22

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In the tabulation below are listed the parts which are usually recommended for stock for normal

maintenance. Other parts are listed on the following pages.

PARTS FOR ALL RATINGS

REF. NO.
27
26
34
45
52
S3
54
56
57

56
SO
60
62
76
146
146
146
147
147

147
147
147
141

176
200B

CAT. NO. FOR
AM-4.1S-7S-1
09S8C0649 G-C002
09S8C0638 O-OOlO
281B793 P-1
236C770 G-5

269C864 P-IB
6301381 P-1
6242891 P-1
2690828 G-2
6301242 G-1
369A460
6301364 P-1
269C828 P-1
6370615 P-1
0958C0637 P-0014
6306734 G-2
6306734 G-3

6306734
6174599
6174599
6275084
' 6174599

G-2
G-4
G-15
G-22
G-11

61^4599 G-3
6174599 G-6
6275017 G-12
6174599 G-2

NO. PER
BREAKER
3
3
3
3
12
12
IS

. 3
3
3
3
3
3
3
1

DESCRIPTION

Movable Arcing Contact
Movable Contact Arm

Booster Cylinder

Operating Rod and Eye Bolt
Primary Contact Finger

Spring (or Primary Contact

^rlng Guide
Buffer-

Arcing Contact
Spring, Outside

^rlng, Inside

Guide Pin
Spring for Arc Contact
Insulation Block

Closing Coll (12Sv d -c)
Closing CoU (2S0v d -c)

Closing Coll (230v a-c)

1
1

Potential
Potential
Potential
Potential
Potential

1
1
1
1
1

Trip CoU
Trip CoU
Trip CoU
Trip CoU
Trip CoU

125v d-c
250v d-c
230v a-c
24v d-e
' 48v d-c

Capacitor Trip Coll

Undervollage Device CoU (230v a-c)

Current Trip CoU (3 Amp. a-c)

6G1-77070

Magno-blast Ctrcuit Breaker

AM 4.14

1
1
1
1
1
1
1

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

ALL
ALL
75
75
78
75
75
78
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

78A
75A
75A

75A
76A
75A
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

ALL
78
75

75
75
78
ALL

2660860 P-4

9580645 P-9

288C698 P-S
456A866 P-1
258C694 P-7
6308734 0-2
6306734 0-3
6306734 0-2

6174599
6174599
6275084
6174599
6174899
6174599
6436456
6242640
6242839
6242636

0-4
0-15
0-22
0-11
G-3
0-6
0-3
P-1
P-1
P-1

6242637 F-1
6438456 0-4
2690659 G-3
684C642 0-1
6003721 P-114
281B792 P-2
281B792 P-3
281B792
2690661
414A14e
2890861

P-4
G-1
P-4
C-4

2690889
2690859
269C8S9
9S6C645
9580645
9580645
058C64S

0-2
P-6
P-6
P-3
P-21
P-19
P-20

1
1
1
1
1

DESCRIPTION

Spring
Support
Spring

Ball Bearing
Disc
Cushion
Guide
Seat
Crank

Plunger
Prop
Stop Blade and Pin
Paddle
Crank

Shaft

1
1
1

Interlock Switch
Shalt

1
1
1
1
1
1
1
1
1
1

1
1
1
1
1

Closing Coll (125v d-c)

Closing CoU (250v d-c)

Closing OotI (230v a-c)
Potential Trip Colt (125v d-c
Potential Trip Coll (350t d-c

Potential Trip Coll (230v a-c
Potential Trip Coll ( 24v d-c
Potential Trip Coil ( 46v d-c

Capacitor Trip Coll
Trip Arm Bracket Asa.
Crank
Arm
Crank Shaft

Trip Latch
Trip Mechanism, Complete

Latch Checking Switch and Support
Terminal Block (6 Point)

Spacer for Terminal Block
1

Plunger

1
1

Rod
Bracket

1
1
1
1
1
4

1
1
2
2
2
4
2
1

ALL

456A343 P-1
6176109 P-71
6242634 P-1

ALL
ALL
ALL
ALL
ALL

6247762 P-1
2690657 P-32
6370567 P-81
2690860 P-2
2690860 0-2

ALL
ALL

2890860 P-6
2690860 P-6
2690860 F-10

ALL
ALL
ALL
ALL
ALL

2690860 P-11

1
1
1
1

6420279 P-1
6076401 P-125
414A146 P-1
2690660 P-20

1
1
1
1

ALL

Manual Trip Assembly
Flex Nut

Support

Bracket Assembly
Plate
Stud

Support
Pin
Pin
Pin

Spring
Spacer

^aeer

Pin
Pin

Bushing
Base Plate
Indicator
Crank and Pin
Clevis
Rod

Support
Pin
Flex Nut
Connection Link

ilMlpfSil
P'iSSWtplBSP®

si
212

221'222 2lO 217 212
223 224

205 210 212

207
Fig. 2IA

Front View

Fig, Zie

Fig. 21

209 220 223'224 212

Rosr Vlev

Current Trip Hechenlen (fief. No. 200}

FAItTS REFERENCED IN FIGS. 21A AND 21B
CAT. NO. FOR

NO. PER

AM-4.ie-2S-l

BREAKER

6ieS9S7 C-13
0174599 G-2

Current Trip &!ectiantsin
Coil (3 Amp. a-c)

0193957 a-7

Sol. Frames and Armature Aasembllee

4905058
0103957
0247930
0370224
6S00725

Solenoid Frame

G-4
P-8
P-1
P-1
P-1

Bearing

Earing Guide
Shaft

Spring

0247928 P-1

0247092
6442998
0508774
6327893

Spacer

P-1
P-1
P-110
P-2

6247929 P-2
6247924 P-l

6247925 P-1
6477094 P-1
6247927 P-t
6247926 P-l
2230575 P-l
2680658 G-4
8077971 P-7
8509718 P-l
6442397 F-1
6509714 P-l

Not Shown

DESCRIPTION

Can lAtch

Latch Bracket Aasembl;
Frame
Pin

Calibrating Tube
Guide Pin

^rlng
Pin

Armature
Guide
Latch
Shaft

^rlng
Guide

Spring

6508707 P-125

Adiuatlng Rod Assembly

6442995 P-l

Clevis

6247919 P-l
0370500 P-9
0193957P-209
6193957 P-34

Calibrating Strip
Cover

Pin
Pin

GEn-77070

Maene-blaat Circuit Breaker Tjrpe AM 4.16-TS

i
Fig. 22

DndervoUase Device, Cover Reitoved (Ref. Mo, 250)
PARTS REFERENCED IN HG. 22

FOR PG-6 AND PG-7 UNDERVOLTAGB DEVICES

REF. NO.

UNDERVOLTAGE
DEVICE TYPE

CAT. NO. FOR

NO. PER

AM-4.16-75-1

MECHANISM

DESCRIPTION

6476723 G-14

Undervoltase Device, Cumplete

6476723 G-38

Undervaltage Device, CoapUte

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

6275017
6275259
6275264
2412699
2437146

Undervoltaec DcvlcCj CoU(2dOvB-c)

ALL

6243262 P-1

Eye Bolt

ALL
pa-6

6440987 P-1

Coupling

6076401 P-101

PG-7

6076401 P-101

Pin
Pin

ALL
ALL
ALL

6440971 P-1

Trip Nut

6440966 P-1
62432B3 P-1
0243291 P-1

Trip Rod

FG-6
INSTANTANEOUS
PO-7
TIME DELAY

PG-7

Not Shown

Cut-out Switch

iterating Lever
Spring
Roller

2239800 P-1

2433013 P-1
6172878 P-1
0300040 G-3

Guide Strip

Spring
Crank and Shaft

Link
Link
Pin

PG-7

6076401 P-106

PG-7
ALL
ALL

6626026
2234096
2236258
2234101

ALL

6301233 0-1

Adjusting Plate

ALL
ALL

6113666 0-4
6043479 P-1

Cover

ALL

G-la
G-1
P-I
P-1
P-1

G-2
G-1
P-1
0-1

Escapement Device
Solenoid Frame

Spring
Core

Thumb Nut for Cover

GEH-2000A

INSTRUCTIONS

supcftscDEs esi'Sooo)

AND

RENEWAL PARTS

POWER

CIRCUIT BREAKERS

Magne-blast Breokers
Types

AM-2.4/4.16-100/150-3
AM-2.4/4.16-100/150A-3
AW1-2.4/4.16-150/2S0-3

AM-2.4/4.16-150/250A-3
With MS-13 Mechonism

I If

MEDIUM

VOLTAGE

SWITCH6EAR

DEPARTMENT

OENERAL0ELECTRIC
PHILADELPHIA, ?A.

CONTENTS

PAGE
INTRODUCTION· ••••••···•• •••·••••··•·••••••••••• •••···••••••••••••••••·•·•••••••••••••·••· 3
RECEIVING HANDLniG AND STORAGE ••••••,·, ·• •••••••, ••·•····••·· ·..,,,••,,, •••••••.• 3
RECEIVING AND HANDLING .•...•••••,...•,, , , , , , •.•• , ••. , ..••,, •,............••...,• 3
STORAGE.....•..,........•••••••...·,•·, •,···•••••,,••·· ···.·•••·•·••...........•..••• 3
DESCRIPTION...•..••........•.•.••••..•••••••.•••..•••••••••••••....•••.••..•.•.••••••..•• 4
INSTALLATION ......••.••..••••.•..•..•••••••,,...•••••,•,,, ••....,•,••, •, •·...•.••••••••.
ADJUSTMENTS .•..... ..•••••• •..•...•••••••••.•...••.•.•••• •...••••..••••.••••••••••••
Primar y Contact Wipe ,..,...•............••••••,..•.•..•,.•, ·.............••....•
Arcing Cont.a-ct Wipe ••..•..• , •••• , ••••••.•••••••••••••••....,, •, •••••.••.••••,••.•
Primary Contact Gap .•••.•.•••••••••.••••.. ••.•••••••••••.....•••••••••...••••.••..
Trip Latch Wipe.•.•••...••... .•.•••••••••.•.•...••••••• •...... . ••..••.•..•• •..••..
Prop Clearance ...•..•............••.••.•.....•..••.....•..·.·.•.....••••.•....•..
C losing Plunger Clearance ..............•,.••••.••.•....•,,..•,.......•.•.., •,.•••
lriterlock Switch Wipe ·••••,.,..··· ···.•··•·•••.•.•.•....••···•·.·.··.••·· ··,.•.•,·
Control Device Adjustment ..··.··,·· ..•.•·•••••••.........·••••..·· ·.,·•,••.••..•·
Cut-off Switch Adjustments ··•·· ·· ··•··· •••· , ·•• , ·.•,·····•·•••· ·····••··••·•·•···
Auxi.liary Devices ••.••..•.........•..•..••.•...........•••••......•., •...•.......•
FniAL INSPECTION AND TEST •••••.•...•....,••••••••••••..•.••••.•.•..... .••••••...
Ht-potential Test ........••...•••,...,........•••.•••...•.....••.. ...........•.•••.
Auxiliary Devices ••••,•••••.•.........•.•••......•..•....•....••......,.•••••••...
Control Power Check...•• ...............••..............•. ....•... ......•...•••...
OPERATION •••.•.•...•.....•.••••••••.•.•..••••..••••••.••.•....••.••••.•••..• ••••.•.....•
CLOSING OPERATION •..•..••.•••••••..••.....•,••,•••.......••••,,,•••..••••••, ••...
OPENING OPERATION .....•.••.•.•., ••.••........,.•,•, ••••.....••..•••••••.••,•,, ••.
TRIP FREE OPERATION ..•.•••.......••.,••........•...•••••,....•...••••..•,•••..•. •

MAmTENANCE .....•.•...••••••.•.••.••....•••••••...•....••.. .•.•.....•...••••.•..•.•....
PERIODIC INSPECTION ..•,.••••••.•••••••..•••.,••.••••••••..•••••••••••..•••••••••.•
Arc Chutes ,, •, ••••••••••••••••••••••••••••••.••••••••••••••••••••••••••••,•.••.•••
Breaker Conta.cts .•...,...•••..........•••...............•...•..... ..••••..•......
Mechanism ·..·,·· · ·.. ···..•.....•...•..,..,...•...•••,........•••.•,•....•.••••.••
Bushings and Insulation ,•,....,,...,•.....,..••..••..,••............,.,....•...,..
LUBRICATION·•••••••••..........•••••••••••......•.
·
,•••••••••.•••••.•..••••••••••..••
Method of Cleaning Bearings ......••·..••...................••.••.......••••••....
TROUBLE SHOOTING ••.. ••••.•••• ••.•.••...••• ••••••••••• .....•••••...••.•••••.••.•..
Failure to Trip .... ............••••••..... ......•••••..••............•...••••.... .
Failure to Close or Latch Closed •.....••.,.......•.......•...••••,..........••.,..
Overheating ··.····...,,,....,.....,,..,...................•••.••,,,...............
REPAIR AND REPLACEMENT ·· ··.··· ···....,•,,••,•••••.•••............••••••••,•...
Arc Chute ·· ·· · ····, ···,·,..,.., ······.......................••...•,••............•
Conta.cts •••••••••••••·•·••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
Bushings ••••••••••·••··•···•· ·· ·•••••••••• •,,,, ••••••••.••.,,, ••••,,•.•.•.•••...••
Closing Coil· ········,,·,···•· ·· · ···· · ·.· ···....,,...................., ....•••...•.
Trip Coil ········ ········,•· ············ ·· ········..................••.•••••••..•.
Interlock Switch···· ··,· ············ ···· · ···,...,..... ............ ......•..•......•
Latch Checking Switch ················· ·· ·· ·······........................•.....,.
Cut-off Switch······· · ···· ···· · ··············· ···•......................,......... .

5
5
5
6
6
'1
7
8
8
8
9
9
10
10
10
11
13
13
13
15

15
15
15
15
15
15
16
16
l '1
17
17
17
18
18
20
21
22
22
23
23
23

RENEWAL PARTS ...•...................••.•..••.••.•.•.•••......•..••••••.•..•..••,•....• 25
ORDERING niSTRUCTIONS, ..,..,,.•,•••.,••,.,,,••,,................................. 25
RENEWAL PARTS ILLUSTRATiON REFERENCES .............,,,, ................... 25

-g

0
N
0

co
>
0

c.)

�
,I
I

(')

...�

MAGNE-BLAST CIRCUIT BREAKERS

TYPE AIW-2.4/4.16 WITH MS-13 MECHANISM
INTRODUCTION
The
Magne-blast Circuit Breaker is the
removable interrupting element for use in vex^callift metal-clad switchgear, to provide reliable con
trol and protection of power systems. Among the
many advantages of metal-clad switchgear are
added protection to equipment and personnel, com

pactness, simplified inst^ation and reduced main

tenance. In keeping with these features the Magneblast breakers are designed for interchangeability
and manueverability, together with reliability and
low maintenance requirements.

The Magne-blast Circuit Breaker operates on
the principle that an arc can be interrupted in air
by sufficiently elongating and cooling it. This is
accomplished by means of a strong magnetic field

The AM-2.4/4.16 Magne-blast Breaker is avail
able to a number of current and voltage ratings.
Refer to the breaker nameplate for the complete

rating information of any particular breaker. The
short circuit conditions to be imposed on the breaker
must not exceed its rating, nor should it be called
upon to operate at voltages or currents greater

ttoui those given on the nameplate. Since this book
is written to cover several ratings of breakers that
are of the same general design, all instructions will
be of a general character and all illustrations will
be typical, unless otiierwise specified.

that lengthen the arc and forces it into intimate
contact with cool dielectric material. A sturdy,

PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SATIS
FACTORY OPERATION OF THE BREAKER. The

reliable operating mechanism assures low mainte

following instructions will provide complete infor

nance and long life, and the use of Self-X insulation
reduces fire hazard to a minimum.

vice and for maintaining satisfactory operation.

mation for placing the magne-blast brewer to ser

RECEIVING, HANDLING AND STORAGE
this is not possible, the following precautions must

RECEIVING AND HANDLING

be taken to insure the proper storage of the breaker:

Each breaker is carefully inspected and packed
by workmen ejqierienced to the proper handling and
packing of electrical equipment. Immediately upon
receipt of the circuit breaker, an examination should
be made for any damage sustained in transit. If
injury or rough handling is evident, a damage claim
should be filed immediately with the transportation
conqiany and the nearest General Electric Sales

1. The breaker should be carefully protected
against condensation, preferably Ity storing
it in a warm dry room, since water absorp
tion has an adverse effect on the insulation

parts. Circuit breakers for outdoor metalclad switchgear should be stored in the
equipment only when power is available and
the heaters are to operation to prevent con

Office should be notified.

densation.
2.

It is e:q)ected that due care will be exercised
during the unpacking and installation of the breaker
so that no damage will occur from careless or rough
handling, or from e^qiosure to moisture or dirt. A
nail puUer should be used to open the crates, and
care should be exercised to prevent tools from
striking either the crate or any part of the breaker.

Loose parts associated with the breaker are always
included to the same crate. Check all parts against
the packing list to be sure that no parts have been

3. Machined parts of the operating mechanism,
etc., shotild be coated with a heavy oil or
grease to prevent rusting.

If the breaker is stored for any length of time,
it should be inspected periodically to see that rusttog has not started and to insure good mechanical

overlooked.

STORAGE

condition.

It is recommended that the breaker be put into
service immediately to its permanent location.

The breaker should be stored to a clean

location, free from corrosive gases or
fumes; particular care should be taken to
protect the equipment from moisture and
cement dust, as tois combination has a very
corrosive effect on many parts.

Should the breaker te

stored under

unfavorable atmospheric conditions, steps should be
taken to dry out the breaker before it is placed to
service.

These instrvetions do not purport to cover all details or variations in equipment nor to provide for every posuble
contingency to be met in connection with installation, operation or maintenance. Should further information be deared

•4

or should particular problems arise which are not covered atffkiently for the purchaser's purposes, the matter should
be referred to the General Electric Company.
3

GEH-200tf Magne-blast Circuit Breakers

1. Secondflry Coupler
2. Auxiliary Switch
3. Position Indicator

4. Opening Spring Unit
Operation Counter
6. Manual Trip
7. Control Device

8. Control Device Plunger
&iide

9. Closing Solenoid

Fig* I

MS-13 Operating Kechanisn

DESCRIPTION
The magne-blast breaker is composed of two
major parts, the breaker element and the operating
mechanism.

The breaker element comprises three

similar pole units, each pole unit consisting of main
and arcing contacts, an interrupter, and an enclosing
box barrier that segregates the interrupting units
from each other to provide insulation between phases
as well as from each phase to ground. The pri
mary connections to theassociatedmetal-clad equip
ment are made through the primary disconnect
studs.

The MS-13 operating mechanism shown in Fig. 1

A positive interlock and interlock switch is
provided between the breaker and metal-clad unit to
prevent the raising or lowering of the breaker in
the unit while in the closed position and to prevent

a closing operation when the breaker is not in
either the fully raised or lowered position. A
plunger type interlock can also be provided to pre
vent the closing of two adjacent breakers at the
same time or to operate an additional auxiliary
switch mounted in the metal-clad unit.

The operating mechanism used on those breakers
designed for MI-6 metal-clad equipment differs
somewhat from those designed for M-26 equipment

is of the solenoid tsrpe designed to give high speed
closing and opening. The closing operation is con

but its operation is principally the same. This
mechanism is controlled by a relay scheme mounted

trolled by the control device (7). The control de
vice also permits trip free operation (tripping the
breaker at any time during the closing operation),
and prevents solenoid pumping (reclosing) after a
trip free operation.
For AC closing operation,

in the metal-clad unit and a cut-off switch located
on the breaker instead of the control device. Two

rectifiers mounted elsewhere in the metal-clad unit

are used to supply the direct current on which the

closing coil operates. The breaker can be opened
^electrically, by remote control, or manually, by
neans of the manual trip device (6). All secondary

seven terminal secondary couplers also replace the
one sixteen terminal coupler. The positive inter
lock between the

breaker and metal-clad mit is

replaced with a trip interlock that trips the mecha
nism t«fore raising or lowering of the breaker can

be accomplished. A fork-type lever can befurnished
to operate an auxiliary switch mounted in the metal-

connections from the breaker to the metal-clad unit

clad unit. For detailed explanation of the opera
tion of the breaker and mechanism refer to the

are made through the coupler (1).

section OPERATION.

Hagne-blast Circuit Breakers GEH-2000

1. Closing Armature

3. Handle

2. Haintenance Operating Device

4. Release Valve

Fig. 2

Method of Mounting Maintenance Operating Device

INSTALLATION
The following instructions explainthenecessary
steps to be taken before the breaker is placed in the
metal-clad unit.

This includes a complete check of

all of the breaker adjustments, in addition to a

thorough inspection. For final installation instruc
tions refer to any issue of the Metal-clad Switchgear

instruction book, GEH-1802. Reference should also
be made to the connection diagram that is furnished
with each unit.

DO NOT WORK ON EITHER THE BREAKER
OR

THE

MECHANISM WHILE IN THE

CLOSED

to the left, the closing armature will return to
its normal position. Electrical operation must not
be attempted until the breaker
been operated
manually through its complete stroke several times
and final installation inspection has been completed.

All adjustments should be checked not only
during the initial installation of the breaker but also
during periodic inspections and whenever it becomes
necessary to repair or replace parts that have t>ecome worn or defective while in service.

The

POSITION XINLESS THE PROP AND TRIP LATCH
HAVE BEEN SECURELY WIRED OR BLOCKED TO

following adjustments are listed in the order in
which they are to be checked. First, however, re

PREVENT ACCIDENTAL TRIPPING.

move the breaker from the metal-clad unit and
remove the box barrier and the mechanism cover.

ADJUSTMENTS

Although the breaker has been completely ad
justed and tested at the factory, it is possible that
unusually rough handling during transportation may
have caused some loosening or disturbance of
parts of the apparatus. It is therefore advisable to
review all adjustments before placing the breaker
in service, making readjustments wherever neces
sary.

A maintenance operating device is provided
for operation of the breaker during these adjust

PRIMARY CONTACT WIPE

When the breaker is closed, as shown in Fig. 3,

the stationary primary contacts (1) should rise
5/16" + 0-1/16". To obtain this adjustment, open
the breaker and, referring to Fig. 4, loosen the
check nut (4) and turn the adjusting nut (3). Screw
ing up on the adjusting nut will decrease the pri
mary contact wipe, down will increase It. Tighten
the check nut, close the breaker and recheck the
wipe.
With the primary contact wipe correctly

Mount the device as shown in Fig. 2,

adjusted, the clearance between the contact arm (7)

and turn the release valve (4) firmly to the right.
To close the breaker, operate the handle (3) with
a pumping motion. By turning the release valve (4)

and the buffer block should be 1/16" or greater
(as shown in Fig. 3} when the breaker is fully

ment checks.

closed.

GEIj[-2000

Magne-blast Circuit Breakers

5" *o"

16,-1'
16,

1. Stationary Pricnary Contacts
2. Movable Primary Contacts
3. Buffer Block

Fig. 3

4. Stationary Arcing Contacts
5. Movable Arcing Contact
6. Upper Arc Runner

Contact Adjustments

ARCING CONTACT WIPE

Refer to Fig. 3. Close the breaker until the
arcing contacts just touch. This can be determined
with the use of a circuit continuity tester such as
a light indication or bell set.
In this position,

the gap between the stationary primary contacts (1)
and the movable primary contact (2) should be 5/16"
or greater.

This setting has been made in the fac

tory and no adjustment is provided. A wipe of less

than 5/16" is usually an indication that Uie arcing
contacts need to be replaced. When making this
check, also see that the movable arcing contact (5)
passes through the slot in the upper arc runner (6)
without touching.
PRIMARY CONTACT GAP

Refer to Fig. 4.

With the breaker closed,

press the manual trip button allowing the breaker
to trip open normally. Do not force the contacts
open wider by hand. The gap between the stationary

primary contacts (5) and the movable primary con
tact (6) should be 3-13/16" + 1/8" - 3/16". To
change this gap, loosen the check nut (25), Fig. 5,
y^d turn the adjusting nut (26) on stud (9). Screw; the adjusting nut down will decrease the pri
mary contact gap.

1. Operating Rod
2. Operating Sod Pin

5. Stationary Primary

3. Adjusting Nut

6. Movable Primary Contacts

4. Oieck Nut

Contacts
Contact Arm

Tighten the check nut and re-

measure the contact gap (close and trip the breaker
before checking the measurement).

Adjusteble Coupling for Making Primary
Contact Wipe Adjustment

Magne-blast Circuit Breakers

GEH-2000

lH=

1. Uain Oper. Shaft
2. Main Crank
3. Trip 9iaft
4. Trip Latch
5. Trip Latch Stop
6. Trip Boiler
7. Position Indicator
8. Clevis
9. Adjustable Stud

Fig. 5

10.

Closing Fin

11. Opening Spring Housing
12. Opening Spring, Inner
13. Opening Spring, Outer
14.
IS.
16.
17.
18.

Closing Boiler
Prop
Closing Coil

Qosing Plunger

Set Screw
Shims

Closing Armature
Stop Niits
Armature Guide Bolts

Stop Huts
Chedc Nut

Adjusting Nut

Piston Bing

Cross Section of HS-13 Mechanisoi

TRIP LATCH WIPE

Refer to Fig. 5.

19.
20.
21.
22.
23.
24.
25.
26.

PROP CLEARANCE

The wipe of the trip latch (4)

on the trip roller (6) should be from 3/16" to l/4".

This can be measured by putting a film of grease on

the latch (4), closing the breaker part way, and
tripping. The mechanism has the proper trip latch
wipe when the latch rests against the stop pin (5).
No adjustment is provided and a visual inspection is
iisually all that is required. If this setting is not
correct, look for insufficient travel of the trip
shaft (3).
WHEN WORKING ON THE MECHANISM IN THE

Refer to Fig. 5. With the breaker closed as far
as possible with the maintenance device, the clear

ance between the closing pin (10) and the prop (15)
should be 1/32" to 3/32". Measure the prop clear
ance with a feeler gage to determine whether or not

an adjustment should be made, and if so, exactly
how much adjustment will be required. To make
the adjustment, it will first be necessary to open
the breaker and remove the maintenance operating
device. Remove the stop nuts (22 and 24) being
careful not to drop the armature (21). Lower the

CLOSED POSITION, KEEP FINGERS CLEAR OF
THE LINKAGE, AS ACCIDENTAL TRIPPING CAN

armature from the mechanism and remove the two

CAUSE SEVERE INJURY.

from the armature and add or subtract the necessary

set screws (19).

Remove the closing plunger (17)

GEH-2000

Magne-blast Circuit Breakers

Sickness of shims (20) to give the required adJuBt-

ent, then replace the closing plunger, screwing it
.own against the shims. Using a small drill, spot
the closing plunger through the set screw hole.
Replace the set screws. To remount the armature
on the breaker, compress the piston ring{18). After

reassembly, remoimt the maintenanceclosingdevice
and check the adjustment.
CLOSING PLUNGER CLEARANCE

Refer to Fig. 5.

With the breaker in the open

position, the clearance between the closing plunger
(17) and the closing roller (14) should be 1/16" to
3/16". To obtain this clearance, the nuts (22) on the
two armature guide bolts (23) may be raised or
lowered.

Both nuts should be moved the same

amount. After making an adjustment, close and
open the breaker and recheck the plunger clear
ance. Repeat the adjustment if necessary.

1. Back Auxiliary Switch

5. Operating Ara

2. Mounting Screw

6. Trip Lever

3. Top Auxiliary Switch

7. Plunger Guide

4. Plunger

Fig. 7

Control Device

(5) the full extent of travel to the rear. With the
device in this position further depress the plunger

(4) on the top auxiliary switch (3). The gap between

the plunger and operating arm should be 1/32" or

greater. To increase the overtravel, loosen the
screws (2) and move the switch toward the rear of
the mounting plate. Tighten the screws and recheck
the adjustment.

In a similar manner, check the overtravel on
the back auxiliary switch (1).
BEFORE MANUALLY OPERATING THE CON

TROL DEVICE, MAKE CERTAIN THAT ALL CON
1.

Interlock Shaft

2. Latch Ch. Sw. Am
3. Inter. Sw. Am

Latch Oieckine Switch

5. Trip Shaft
6.

Interlock Switch

TROL POWER TO THE BREAKER HAS BEEN
DISCONNECTED.
MANUAL OPERATION OF THE
CONTROL DEVICE WITH CONTROL POWER CON
NECTED WILL ENERGIZE THE CLOSING COIL
AND PRODUCE A CLOSING OPERATION.

Interlock Switch and Latch Checking Switch

INTERLOCK SWITCH WIPE

Referring to Fig. #6, rotate the interlock shaft (1)
manually clockwise to release the interlock switch
arm (3). The point at which the contacts make can
be determined with a circuit continuity tester such

as a light indicator or bell set. To obtain adjustment
on the interlock switch (6), bend the interlock switch
arm (3).
The roller and crank on the interlock
switch
(6) should have 1/32 to 1/16 overtravel
after final adjustment.

^ONTROL DEVICE ADJUSTMENT

CUt'Off Switch

5. Lever Arm

2. Switch Plunger

3. Adjusting Bolt

7. Adjustment Screw
8. Plunger Guide

Washers

Referring to Fig. 7, measure the overtravel of

the two auxiliary switch plungers. Manuallyoperate
the control device by pressing the operating arm

Fig. 8

Cut-off Switch Adjustments

Magne-blast Circuit Breakers

GEH-2000

1. Front Disconnect Stud
2. Interlock Bolt
3.

Washers

4. Connecting Rod
5. Reset Plate
6. Reset Roller

7. Main Operating Shaft

8. Reset Arm

9. Trip Plate

10. Spring
11. Trip Bolt
12. aevis

13. Elevating Bar

14. Impact Trip Plate
15. Trip Latch
16. Trip Roller
17. Trip Armature
18. Trip Lever

19.
20.
21.
22.
23.

B
Fig. 9

Uhdervoltage Trip Hammer
Adjusting Rod
Manual Trip Button
Trip Setting Plate
Undervoltage Device

Adjustments On Current Trip Device and Undervoltage Trip Device,
Shown With The Breaker In The Closed Position

In order to trip properly, the clearance between

CUT-OFF SWITCH ADJUSTMENTS

(AM-2.4/4.16-100/150A-3, -150/250A-3)
Refer to Fig. 8. With the breaker in the open
position, the clearance between the switch plunger
and the adjusting screw is obtained by pushing the
switch plunger (2) in as far as possible. In this
position the clearance between the switch plunger

(2) and the adjustment screw (3) should be not more
than 1/32". If adjustment is necessary, add or
remove washers (4) as req\iired.

the trip bolt (11) and the trip plate (9) should be
1/32" to l/l6". This can be altered by releasing
the check nut and screwing the trip bolt (11) in or
out of the reset arm (8).

When an undervoltage device is furnished check
the clearance between the trip hammer (19) and the

trip plate (14), with the undervoltage coil energized.

This clearance should be 1/32" to 1/16" and can
be altered by removing the connecting pin at either

end of the adjusting rod assembly (20), and turning

the clevis at that end.
AUXILIARY DEVICES

After checking all the mechanical adjustments
as outlined above, operate the devices manually to
make certain that tiiey trip and reset properly.

Latch Checking Switch Wipe

Referring to Fig. #6, rotate the trip shaft (5)
manually clockwise to release the latch checking

switch arm (2).

The point at which the contacts

make can be determined with a circuit continuity
tester such as a light indicator or bell set.

Plunger Interlock

(AM-2.4/4.16-100/150-3 and 150/250-3)

Refer to Fig. 9.

With the breaker in the open

position, the vertical distance "A" from the top of

obtain adjustment on the latch checking switch (4),
bend the latch checking switch arm (2), The roller

the interlock bolt (2) to the bottom of the elevating

and crank on the latch checking switch (4) should

this adjustment add or remove washers (3).

have 1/32 to 1/16 overtravel after final adjustment.

bar (13) should be 15-19/32" + 1/16". To change

Auxiliarv Switch Linkage
Impact Trip. Current Trip. Capacitor Trio, and
Undervoltage Trip Devices

Fig. 9 shows the necessary settings that are

Refer to Fig. 10. With the breaker in the open

to be checked when these devices are furnished.

position, the distance from the center line of the
front bushings (1) to the center of the slot in the
fork lever (2) should be 12-9/32" as shown. To

The amount of wipe between the trip roller (16)
and the trip latch (15) should be 3/32" to 5/32".

(!Furnished Special on AM-2.4/4.16-100/150A-3 and
-15Q/250A-3T

This can be altered by changing the number of shims

change this setting, loosen the locking bolts (3) and

stops.

the lock bolts.

under the block against which the trip plate (14)

move the fork lever in the proper direction. Tighten

lanation of Copperoxide Rectifiers for circuit breaker application,
refer to Instruction Book GEI-11306.

To check the DC voltage at the closing coil
terminals, proceed as follows:

CONTROL POWER CHECK

After the breaker has been closed and opened

slowly several times with the maintenance closing
device, and the mechanism adjustments checked as
described above, the operating voltages should be

checked at the closing coil and trip coil terminals.
For electrical operation of the breaker, the control
power may be either an alternating or direct cur
rent source. The operating ranges for the closing
and tripping voltages are given on the breaker name-

plate.

Ordinarily, standard ranges apply which are

as follows:

CLOSING
RANGE

NOliIINAL
VOLTAGE

TRIPPING
RANGE

125V. DC

90-130V. DC

70-140V. DC

250V. DC

180-260V. DC

140-280V. DC

230V. AC

190-250V. AC

1. Mechanism with a control device. Fig. 11. Close
the breaker by manually operating the control
device. Hold the contacts in the closed position
and read the DC voltage at the closing coil termi

nals.

To de-energize the circuit, release the

control device.

2. Mechanism with cut-off switch. Fig. 8. Close
the breaker by manually operating the control

relay located in the me&l-clad unit. Hold the

relay closed and read the DC voltage at the
closing coil terminals. Release the closing
relay to de-energize the circuit.
DO NOT MAINTAIN VOLTAGE ON THE CLOS
ING COIL ANY LONGER THAN THE FEW SECONDS

REQUIRED TO READ THE VOLTMETER. These
coils are designed for intermittent operation and
will be damaged by prolonged current flow.
If the closed circuit voltage at the terminals

7NOTE: Where repetitive operation is required from
a direct current source, tiie closed circuit voltage

at &e closing coil should not exceed 115V. DC and
230V. DC at the nominal voltages of 125V. DC and
250V. DC respectively.

of the closing coil does not fall in the specified
range, proceed as follows:

1. AC control power source - Decrease the series
resistance to increase the DC voltage, or in
crease the series resistance to decrease the DC

For AC operation, two copper-oxide rectifiers,
mounted elsewhere in the metal-clad unit, are used.
A tapped resistor is provided in each rectifier
circuit to control the DC voltage. The resistor

set^g should be adjusted so that the closed circuit

voltage.

Recheck voltage at the closing coil.

2. DC control power source - Check voltage at the
source of power and line drop between the power
source and breaker.

voltage at the breaker closing coil terminals is 110
to 120 volts DC.

Where repetitive operation is

required, the voltage should be set at 105 to 115
volts DC.

»AC Volts

(Closed Circuit)

190-196
194-206
204-216
214-226
224-236
234-246
244-250

Resistor Setting, Ohms
Summer

1/4
1/2
1/2
3/4
1

1-1/4
1-1/4

Winter
0
0

1/4
1/4
1/2
3/4
1

When two or more breakers, operating from the
same control power sotirce, are reqtdred to close
simultaneously, the closed circuit voltage at the
closing coil of each breaker must fall mthin the
specified limits.

Electrical closing or opening is accomplisned
by merely energizing the closing or trip coil cir
cuit. Control switches are provided for this purpose
on the metal-clad unit.

It is also possible to trip

the breaker manually by pressing the manual trip
button (6), Fig. 1.
When all the foregoing inspection details have

been checked, the breaker may be safely placed in
service. Before the breaker is finally r^sed into
position in the metal-clad unit, rub a small amount

* AC Volts as measured across the rectifier and
AC series resistor.

of G. E. Contact Lubricant D50H28 on the silvered

portion of the breaker studs to form a thin coating
for contacting purposes.

The above tabulation is included as a guide

for adjusting the resistors for the particular com
bination of ambient temperature and AC supply

vol^ge. Summer settings are used where ambient
temperatures are normally above freezing (32°F).

It is necessary to use winter settings where the

NOTE:

This

breaker mechanism combination

is designed only for electrical closing when in use.
NEVER ATTEMPT MANUAL CLOSING WITH THE

BREAKER IN SERVICE, for under such conditions,
sufficient closing force and speed cannot be applied.
11

GEA-2000 Magne-blast Circuit Breakers

6. Uovable Contact Assembly

1. Shunting and Anti-Pump Switch
Seal-in Switch

Arm

3. Operating Coil

Arc Chute

9. Trip Lever

Crank

Stationary Contact Assembly

Fig. li

10. plunger Guide

Control Device

r—

1. Main Crank

2. Trip Latch

3. Trip Roller

8. Spring Retainer

9. Opening Spring, Inner
10. Opening Spring, ^ter

6. Closing Armature

11. Closing Pin
12. Prop
13. Closing Coil

14. Closing Plunger Rod

4. Closing Roller

5. Piston Ring
Armature Guide Bolts

Fig. 12

Cross Section Ot MS-13 Operating Mechanism jn Tlie Open Position

Magne-blast Circuit Breakers GEH-2000

OPERATION
CLOSING

OPERATION

The closing operation of the breaker is pri
marily controlled
the control device. Fig. 11,
mounted on the operating mechanism. The closing
sequence is initiated from a control switch mounted

the average speed of the movable arcing contact
from a point 1" before the tip is tangent to the lower
surface of the upper arc runner to the tangent
position.

OPENING

on the door of the metal-clad unit or at a remote

operating station.

Operation of the closing control

switch energizes the pick-up coil of the control

device.
As the control device closes, seal-in
contacts shunt the closing control switch to allow

the opening of the closing control switch contacts
without affecting the overall closing operation.

This ^e of arrangement assures complete closing

of the breaker wiUi only momentary contact of the
closing control switch.

load side of the breaker.

By energizing the trip

coil, the trip plunger rotates the &ip latch (2),

Fig. 12, causing the operating mechanism linkage to
course. The energy stored in the opening springs
(9 and 10) is thus released, opening the breaker.

in turn lifts the closing roller (4) through plunger

first, shunting the current throu^ the arcing con

the breaker contacts. As the armature reaches the

end of its travel, the prop (12) rotates beneath the
pin (11) latching the breaker in the closed position.
Dwing the closing operation, the opening springs

(9 and 10) are compressed in readiness for an

opening operation. Ar trapped above the armature

acts as a dash pot to absorb the energy of the
mechanism as it approaches the end of its stroke.

Slightly before the mechanism latches, the
control device plunger (5), Fig. 23, mechanically
trips the main control device contacts, de-ener
gizing the closing coil and allowing the armature
to return by gravity to its original position. The

and current devices used to detect a fault on the

During this operation, the trip coil circuit is deenergized, and upon completion of the opening oper
ation, the operating mechanism is returned to its

(14). This motion is transmitted through the mecha
nism linio^e and rotates the main crank (1), closing

An electrical opening operation is initiated by

energizing tiie trip coil. This is accomplished
either by actuating the opening control svtitch on
the metail-clad unit or by a combination of rplays

Operation of the control device energizes the
breaker closing coil
closing the main control
device contacts (5 and 6), Fig. 11. Once the control
device contacts are picked up, they are electrically
held in the closed position until the breaker closing

operation is completed. Energizing the breaker
closing coil raises the armature (6), Fig. 12, which

OPERATION

control device plunger also mechanically trips the
seal-in switch, de-energizing the control device
coil if the closing control switch is not closed. If
the closing control switch is held in the closed
position throughout and after the breaker closing
operation, the control device linkage will remain
picked up and be unable to reset to prepare for
another breaker closing operation. This arrange
ment insures that "pumping" of the breaker will not
occur during a trip-free operation.

normal position, ready for closing.

As the breaker opens, the main contacts part

tacts.

An arc forms as the arcing contacts part.

See Fig. 13. As the movable arcing contact (27) is

withdrawn tiirough the slot in the arc runner, the
tqpper end of the arc is transferred to the upper
arc runner (4).

tube (28) and forces the arc onto the lower arc
runner (10). Establishment of the arc on the runners

automaticailly inserts the blowout coils into the

circuit, introducing a magnetic field between the
pole pieces which tends to draw the arc away from

the arcing contacts. The 250 MVA interrupter con
tains one upper magnetic blow-out coil and one lower
blowout coil, each individually connected in series
with its respective arc runner. The arc is forced
outward along the diverging arc runners by the
magnetic field.

At the same time, the arc is being forced into
the arc chute (8) which is composed of a series of

gradually interleaving insxilating fins. These fins,
which project alternately from the two opposite
inner surfaces of the chute, elongate the arc into
a gradually deepening serpentine path, so that the
electrical

designed for MI-6 met^-clad equipment is similar
to timt described atove except that a relay mounted
elsewhere in the metal-clad unit replaces the con
trol device. Also, a cut-off switch (Fig. 8) is used

resistance in the path of the arc is

rapidly increased and the heat from the arc is
absorbed.

The operating sequence for those breakers

To assist the interruption at tiiis

point, a stream of air is emitted from the booster

the
and
and
arc

The increased resistance reduces both

magnitude and the phase angle of the current,
at an early current zero the arc path is so long
the gases produced by the arc so cooled that the
cannot re-establish itself, and interruption oc

curs.

to replace the mechanical trip arrangement of the
control device.

The cut-off switch energizes an

auxiliary relay to de-energize the main relay.

The closing speed of the arcing contact should

be 7 to 10 feet per second for the 100/150 J^A
breakers and 9 to 12 feet per secondfor the 150/250

MVA breakers with rated closed circuit voltage at

the closing coil terminals. These speeds represent

The 150 MVA interrupter is essentially the
same as the 250 MVA interrupter except that it
utilizes the magnetic elements in the upper runner
only.

Manual tripping follows the same procedure
except that instead of energizing the trip circuit,

the manual trip (6), Fig. 1, is used.
13

'GEH-2000 Magne-blast Circuit Breakers
\

s
o

s
(*)

2. Blow*out Gore
3. Blow-out Coil
4. Arc Runner

16. Frame
17. Operating Crank
18. Upper Horizontal
19. Spring Retainer

5. Pole Piece

20. Lower Horizontal Barrier

1. Box Barrier Handle

6.
7.

Stationary Arcing Contact

Box Barrier
8. Arc Chute
9. Pole Piece
10. Arc Runner

11. Blow-out Coil
12. Blow-out Core

13. Uuffler
14. Front Bushings
IS. Rear Bushings

Fig. 13
14

Barrier

21. Operating Rod
22. Stationery Primary Contacts
23. Movable Primary Contacts
24. Cup Bearing
25. Yoke
26. Movable Contact Arm Assembly
27. Movable Arcing Contact
28. Booster TUbe
29. Connection Bar
30.

Booster Cylinder and Piston

Cross Section Of Breaker Pole Unit

Magne-blast Circuit Breakers

The opening speed of the arcing contact should
be 12 to 18 feet per second at rated control voltage.
This speed represents the average speed over 3" from
the point when the tip on the movable arcing contact

Is t^gent to the lower surface of the upper runner.

TRIP FREE OPERATION
If the trip coil circuit Is energized while the

GEH-2000

breaker Is closing, the trip plunger will force the

trip latch (2), Fig. 12, away from the trip roller
(3) causing the mechanism linkage to collapse and
the breaker to re-open. The closing armature (6)
completes Its closing stroke, but the closing coll

Is de-energlzed at the end of the stroke, and the
armature Is returned to Its original position by
gravity.

MAINTENANCE

Dependable service and safer power equipment
are contingent upon the unfailing performance of the
power circuit breaker. To maintain such service, It
Is recommended that a definite Inspection and main
tenance schedule be set up and followed, as serious

operation of tee device In any way and should be
disregarded.

shutdowns can often be avoided by locating potential
sources of trouble In an early stage. Aperlo^c

3. If tee arc chute has suffered any mechanical in
jury due to dropping or accidental striking, re
sulting In tee actual breaking off of fins, replace
ment of tee chute will be necessary.

Important for tee successful operation of tee break

BREAKER CONTACTS

lubrication of parts subject to wear Is also vitally
er.

BEFORE ANY MAINTENANCE WORK IS PER

FORMED, MAKE CERTAIN THAT ALL CONTROL
CIRCUITS ARE DE-ENERGIZED AND THAT THE
BREAKER IS REMOVED FROM THE METAL-CLAD
UNIT.
DO NOT WORK ON THE BREAKER OR
MECHANISM WHILE IN THE CLOSED POSITION
UNLESS THE PROP AND TRIP LATCHHAVEBEEN
SECURELY WIRED OR BLOCKED TO PREVENT
ACCIDENTAL TRIPPING,

PERIODIC INSPECTION
The frequency of periodic Inspection should be

determined by each operating company on the b^ls

of tee number of operations (tecludingswitching), the

magnitude of currents Interrupted, and any unusual

(derations which occur from timetotime, (^eratlng
e^erlence will soon establish a maintenance sche-

ule which will give assurance ofproper breaker con

By removing tee box barrier tee movable and
stationary primary contacts and tee movable arcing
contacts can be Inspected. The stationary arcing
contacts can be Inspected only after removing tee
arc chute assembly, as explained under REPAIR
AND REPLACEMENT.

If tee contacts are burned

or pitted, they should be made smooth with a fine
file.

After completing Inspection of tee contacts,
check the contact adjustments as specified under

INSTALLATION, ADJUSTMENTS.
MECHANISM

A careful Inspection should be made to check

for loose nuts or bolts and broken retaining rings.
All cam, roller, and latch surfaces should be In
spected for any evidence of damage or excessive
wear. Lubricate the mechanism as outlined below,
then, using the maintenance operating device, open

dition. On Installations where a combination of fault

and close the breaker several times to make certain

spection Is recommended after any severe fault

that the mechanism operates freely throughout Its
entire stroke. Check tee mechanism adjustments
as specified under INSTALLATION, ADJUSTMENTS.

duty and repetitive operation Is encoimtered, an In
(deration.

The following Instructions list tee main

points to be Included In an Inspection, and a number
of general recommendations.

Check all terminal connections.

ARC CHUTES

BUSHINGS AND INSULATION

It Is not necessary to inspect the arc chutes
unless there Is evidence of damage or if tee arc
chutes are removed for any reason. WhenInspecting

The surface of the Self-X bushings should be
kept clean and unmarred to prevent moisture ab

an arc chute. It should be disassembled and the
following points noted:

damaged. It should be sanded and cleaned,-and should
be reflnlshed with either clear varnish (GE-1170)

1. Scale formed over tee surface of tee arc chute

smooth and hard.

must not be removed, but loose particles col

sorption.

If the Insulation surface should become

or clear »Glyptal resin (GE-1202). Allow to dry

lected In tee chute should be blown out.

2. Cracks which have formed in the fins of the arc
chute are to be expected In ceramic materials of
this tjrpe when subjected to the severe heat of an

♦

arc.

These cracks do not Interfere with the

All other Insulation parts on tee breaker should
be kept clean and dry. Smoke or dust collected be

tween Inspection periods should be wiped off, and
if dampness Is apparent, heaters should be Installed

to Insure dryness.

* Reg. Trade-Mark of General Electric Co.
15

'GEH-2000

Magne-blast Circuit Breakers
General Electric Lubricant D50H15 and D50H28

LUBRICATION

is available in 1/4# collapsible tubes.

In order to maintain reliable operation, it is

important that all circuit breakers be properly lu
bricated at all times. During assembly at the fac

tory, all bearing surfaces, machined surfaces, and
all other parts of the breaker and mechanism subject
to wear have been properly lubricated using the

finest grade of lubricants av^lable. However, even
the finest oils and greases have a tendency to oxi
dize with age, as evidenced by hardening and dark
ening in color. Elimination of the hardened lubri
cant is essential for the proper operation of cir
cuit breakers. Also frequent operation of the breaker
causes the lubricant to be forced out from between

the bearing surfaces. A simple lubrication wiU
odten clear up minor disturbances which mii^t be
mistaken for more serious trouble.
A

dation;

Wherever cleaning is required, as indicated in
the lubrication chart, the following procedures are
recommended:

Sleeve Bearings

The pins should be removed and all old oxidized
grease removed by immersion in clean petroleum
solvent or similar cleaner. DO NOT USE CARBON-

Wipe the bearing clean. Apply

entire surface of the bearing and pin just before

ation of the breaker and local conditions.

reassembling.

such a schedule is worked out, the breaker should
be lubricated at each periodic inspection and also
whenever it is overhauled, in accordance with the
lubrication chart. Fig. 14. It is also recommended
that all circuit breakers be operated at regular
intervals to insure the user that the equipment is
operating freely.

a small amount of G. E. Lubricant D50H15 to the

up taking into consideration the frequency of oper
Until

METHOD OF CLEANING BEARINGS

TETRACHLORIDE.

definite lubrication, schedule should be set

It is so

packaged to insure cleanliness and to prevent oxi

^mm^ble Seal and Open Type Ball. Roller and
Needle Hearings

The bearings should be first removed from the
mechanism and disassembled by the removal of the
seals or inner race in the case of needle bearings.

The lubrication chart is divided into two meth
ods of lubrication. The first method outlines the

maintenance lubrication which should be performed
the time of periodic maintenance, and requires
AO disassembly.
The second method outlines a
~ lubrication procedure similar to that performed on
the breaker at the factory, but should be used only
in case of a general overhaul or disassembly for
other reasons, or if the operation of the breaker
becomes slower.

Part

They should then be placed in a container of clean
petroleum solvent or similar cleaner. DO NOT USE
CARBON-TETRACHLORIDE.

H the grease in the

bearings has become badly oxidized it may be
necessary to use alcohol (type used for thinning
shellac) to remove it. Ordinarily, by agitating the
bearings in the cleaning solution, and using a stiff
brush to remove the solid particles, the bearings
can be satisfactorily cleaned. Do not handle the
bearings with bare hands as deposits from the skin

Lubrication at

Alternative Lubrication

Maintenance Period

(Requires Disassembly)

Ground surfaces such as

Wipe clean and apply

cams, rollers, latches, etc.

D50H15.

Sleeve Bearings
(Mechanism and Breaker
linkage)

Very light application
of light machine oil

Remove pins and links
and clean as per cleaning

SAE-20 or -30.

instructions above.

Apply D50H15 liberally.
Light application of
light machine oil

Clean as per cleaning

Open Type Ball,
Roller and Needle Bearings

SAE-20 or -30.

repack with D50H15.

Silver Plated Contacts

Wipe clean and apply

and Primary Disconnect Studs

D50H28.

No lubrication re

Wipe clean and apply D50H15.
(No lubrication is required on
the loose rings between bushing
and contact arm).

Removable Seal and

Cup Bearing

quired.

k
Fig. ji)
16

Lubrication Chart

instructions above and

Magne-blast Circuit Breakers GEH-2000
onto the bearings are
bearings are touched,
moved by washing in
have been thoroughly

inducive to corrosion. If the
the contamination can be re
alcohol. After the bearings
cleaned, spin them in clean

new light machine oil until the cleaner or solvent

is entirely removed. Allow this oil to drain off and

then repack them immediately with G. E. Lubricant
D50HI5 being sure all metal parts are greased.
The removable seals should then be replaced.
NOTE: If it becomes necessary to clean the

bearings in alcohol (shellac thinner; be sure the
alcohol is perfectly clean, and do not allow the
bearings to remain in the alcohol more than a few
hours.

If it is desirable to leave the bearings in

the alcohol for a longer time, an inhibited alcohol
such as is used for anti-freeze should be used.

Even then the bearings should be removed from the
alcohol within twenty-four hours.
Esso AntiFreeze and Du Font Zerone are satisfactory for

this purpose. Precautions against the toxic effects
of the alcohol must be exercised by wearing rubber

gloves and by using the alcohol in a well ventilated

lack of lubrication.

REMEDY: Lubricate complete mechanism.

2. Mechanism binding or sticking caused by
being out of adjustment.
REMEDY: Check all mechanism adjust
ments, latches, stops, auxiliary deviws,

etc., in accordance with INSTALLATION,

ADJUSTMENTS. Examine latch and roller
surfaces for corrosion.

3. Control device sticking or not operating
properly.
. ^ ,
REMEDY: Check and adjust control device,
or replace.

4. Damaged or dirty contacts in control cir
cuit, including control device.

REMEDY: Recondition or replace contacts.

5. Damaged control device coil.
REMEDY: Replace damaged coil.

room; excessive exposure to the fumes is some

6. Damaged closing coil.
REMEDY: Replace danoaged coil.

then apply the lubricant.

7. Defective cut-off switch, latch-checking
switch, or interlock switch.
REMEDY: Replace defective switch.

times uiqileasant to personnel. Washingthe be^ings
in light oil and drabiing should follow immediately,
TROUBLE SHOOTING
Failure of a breaker to operate properly will

generally fall within three general classes: Failure
to trty, failure to close or latch closed, and over
heating. The following is a brief outline showing
particular tjnpas of distress that might be encount
ered, together with suggestions for remedsdng the
trouble:

FAILURE TO TRIP

1. Mechanism binding or sticking caused by
lack of lubrication.

REMEDY: Lubricate complete mechanism.

2. Mechanism binding or sticking caused by
being out of adjustment.
REMEDY: Check all mechanism adjust

ments, latches, stops, auxiliary devices,
etc., in accordtoce with INSTALLATION,
ADJUSTMENTS.

Examine latch and roller

8. Blown fuse in closing circuit.

REMEDY: Replace blown fuse after deter
mining cause of failure.

9. Faulty connections in closing circuit.
REMEDY: Repair broken or loose wires
and see that all binding screws are tight.
10. Insufficient control voltage caused by ex
cessive drop in leads.
REMEDY: Install larger wires and improve
electrical contact at connections.

11. Insufficient control voltage caused by poor

regulation (AC control).
REMEDY: Install larger control transfor
mer.

Check rectifier to be sure it is de

livering adequate DC supply.
OVERHEATING

surfaces for corrosion.

3. Damped trip coil.

REMEDY: Replace damaged coil.

1. Poor condition -of contacts due to lack of
attention after severe duty or too frequent
operation.

REMEDY: Recondition or replace burned
4. Blown fuse in trip circuit.

REMEDY: Replace blown fuse after deter
mining cause of failure.

5. Faulty connections in trip circuit.
REMEDY: Repair broken or loose wires
and see that all binding screws are tight.

and pitted contacts. (Contacts should be re
conditioned very carefully and only when
absolutely necessary.)
2. Contacts not properly aligned or adjusted.
REMEDY: Check all adjustments in ac
cordance with INSTALLATION, ADJUST
MENTS.

6. Damaged or dirty contacts in trip circuit.
REMEDY: Recondition or replace contacts.

3. Breaker kept closed or open for too long a
period.

FAILURE TO CLOSE OR LATCH CLOSED

1. Mechanism binding or sticking caused by

REMEDY: Operate breaker more often to
wipe contacts clean. Replace contacts if
necessary.

GEH-2000
4.

Mag:ne-blast Circuit Breakers

Overloading.
REMEDY: Replace breaker with one of ade
quate rating for present or future load, or
re-arrange circuits so as to remove excess

raising the complete arc chute assembly about 3/8"
and sliding it toward the rear of the breaker it can

load.

be removed as shown in Fig. 15.

two upper supporting bolts (2), Fig. 15, and the one

lower supporting bolt (9) using a 3/4" wrench. By

5. Primary connections of inadequate capacity.
REMEDY: Increase size or number of con
ductors or remove excess current.

Loose connections or terminal connectors.

REMEDY: Tighten.
7. Ambient temperature too high.

REMEDY: Relocate in a cooler place, or
arrange some means of cooling.

REPAIR

AND

REPLACEMENT

The following information covers in detail the
proper method of removing various parts of the

breaker in order to make any necessary repairs.
This section includes only those repairs that can
be made at the installation on parts of the breaker
that are most subject to damage or wear.
IMPORTANT:

UPON COMPLETION OF ANY RE

PAIR WORK, ALL BREAKER AND MECHANISM
ADJUSTMENTS MUST BE CHECKED. Refer to the

section on INSTALLATION, paying particular at
tention to ADJUSTMENTS and FINAL INSPECTION.

/i*^RC CHUTE

To remove an arc chute, first open the breaker
and remove the box barrier (7), Fig. 13. Loosen the
1.

Assembly Bolts and

Molded Caps

9. Assembly Bolt

2. Assembly Bolts

10. Upper Mounting Support
11. Assembly Bolt

3. Upper Pole Piece

12.

Assembly Bolt

13. Assembly Bolt

Side Brace

14. Lower Mounting

Lower Pole Piece

7. Assembly Bolt

Support
15. Assembly Bolts

16. Assembly Bolts

Lower Brace

Fig. 16

Side Shield

Arc Chute Assembly Complete

To disassemble the arc chute after it has been
removed from the breaker, proceed as follows:

1. Remove the assembly bolts (7, 9, 11 and 13).
Fig. 16.

2. Remove ihe side brace and pole piece as
sembly (5), Fig. 16.
1.Kear Bushing
2. Supporting Bolt
3.tJpper Mounting Support
4. Stationary Aicing

^ Contact Assembly
^Movable Arcing Contact
15

6. Assembly Bolts
7. Brace

for Arc Qiute

8.Arc Chute Mounting

3. To remove the upper mounting support (10',
Fig. 16, remove the assembly bolls (1) and

connection screw (2), Fig. 18."

Brack et

9.Lower Supporting Bolt
lD.L.ower Siounting Support

Arc Chute Partially Removed Showing

Accessibility of Arcing Contacts

4. Remove the assembly bolts (16), Fig. 16 to
remove the lower brace (8).
5. Remove the lower mounting support (141.
Fig. 16, by removing the assembly bolt.«-

(15) and the connection nut (9), Fig. l£.

Magne-blast Circuit Breakers

I 1

GEH-2000

'•.\i

5=1=

1. upper Are Runner
Spacers

2. Upper Arc Runner
Assembly
3.

Blowout Core

Blowout Coil

Insulation

Upper Arc Runner

Arc Chute Side

Fig. 17

Upper Insulation

9.
10.

Lower Arc Runner
Blowout Coil

11.

Blowout Core

12. Lower Arc Runner

Assembly
13.
14.

Lower Coil Connection
Lower Arc Runner

Spacers

6. Side Shield
7.Lower Arc Runner

removed.

by removing the various screws and 1/4"
assembly bolts (not illustrated) as shown
in Fig. 17.

8. The arc chute sides (6), Fig. 17, can be
separated by removal of assembly bolts (2
and 4), Fig. 16.

B.Lower Coil Connection

4.Upper Arc Runner

9.Connection Nut

Assembly

5. Upper Arc Runner

Fig. 18

10.Lower Mounting Support

Front View Arc Chute Assembly

4. Before bolting the upper mounting support
in place, make certain that the upper arc
runner assembly is tight against the arc
chute side so that the gap between the upper
insulation (7), Fig. 17, and the arc chute
side (6) is a minimum.

Further disassembly of both the upper and
lower arc runner assemblies can be done

Assembly

3.t^per Blowout Cbil

Arc Chute Assembly with Side Removed

6. At this point the fiber side shields (6).
Fig. 18, the upper arc runner assembly (4)
and lower arc runner assembly (7) can be
7.

1. upper Mounting Support
2. Connection Bolt

5. Make

certain that the electrical connec

tions (2 and 9), Fig. 18, are tight.
To reassemble the arc chute to the breaker,
proceed as follows:

1. Rest the lower mounting support (10) on
the arc chute mounting bracket (8) as shown
in Fig. 15.

Reassemble the arc chute in the reverse order.

The following items should be noted during re
assembly:

1. Equally

space the fins of the arc chute

sides before bolting together.
2. Check to insure that electrical connections

to the blowout coils are tight.

3. When reassembling the arc runner assem

blies, check that the spacers (1 and 13),
Fig. 17, are correctly installed.

Slide

the

arc

chute

forward

and

lift

slightly to engage the supporting bolts (2),
Fig. 15, in the slots of the upper mounting
support (3).

3. Tighten the supporting bolts (2 and 9), Fig.
15.
These bolts serve as both the elec
trical and mechanical connections between

the bushing and the arc runners.

4. Check that the movable arcing contact (5),
Fig. 3, passes through the slot in the upper
arc runner (6) without touching.

GEH-2000

Magne-blast Circuit Breakers
CONTACTS

Open the breaker and remove the box barrier
and arc chutes as previously described. To remove
the contacts, proceed as follows:

Stationary Arcing Contacts (10), Fig. 19
1. Disconnect the contact braids from contact

fingers by removing two bolts (8), Fig. 19.

2. Grasp the lower end of the contact fingers
with pliers and pull contact assembly down

ward to remove from stud assembly.
3. To disassemble braids from stud assembly,

rediove one bolt (5).
4. To disassemble stud assembly from contact

support, remove two bolts (6).

5. Reassemble in the reverse order.

1. Rear Bushing
2. Guide and ^pport
for Arc Chute

3. Bolts for Contact

Support
4. Cbntact Support
5< Bolt for Flexible Braid

6. Mounting Bolt
7.

Flexible Braid

Connection Bolt

finger out of contact support (7). Remove
one contact finger at a time.

9. Stud for Mounting

1. Place the finger (9) on contact support (7)
so that it is retained by stop plate (8).
2. Open spring compressor (3) and assemble

Stationary Arcing
Contact Assembly

spring guide, spring and spring compres
Fig. 19

1.Spring Guide
2.Handle for Spring Compressor

6. Spring

3. Spring Cbmpressor
4iSpring Retfiner

8.Stop Plate

Si Assembly Bolt

7.Contact Support
g.Stationary Primary

Contact Fingers

for Spring Retainer
20

sion (Fig. 20A).

Rear Bushing Assembly

Method of Installing Primary Contact
Springs Using a Spring Compressor

1. Contact Springs
2. Stationary Primary

6. Assembly Bolts
7. Movable Arcing

Contacts

Contact

8. Assembly Bolts

3. Cup Bearing
4.

Contact Arm

5i Movable Primary Contacts
Fig. 21

g;
2

—

To replace the Stationary Primary Contacts

Arcing Fingers

10.

Stationary Primary Contacts (9), Fig. 20
1. Compress the contact spring (6).
2. Remove spring and spring guide (1).
3. Raise the contact finger to clear the primary contact stop plate (8) and lift the

Connection Bar

10. Piston Assembly

Removal of Contacts

®
"•

Magne-blast Circuit Breakers GEH-2000
3. Turn handle (2) in clockwise direction to

compress contact spring (Fig. 20B). Hold

spring firmly in yoke on spring compressor

to prevent the spring from slipping out of
the compressor.

4. Place washer (not shown) on ^ide on top
of spring, place top of guide into hole in

spring retainer (4) and the round end of
spring guide in cut out in primary finger
(Fig. 20C).

5. Hold spring assembly firmly in place and
remove spring compressor.

and arc chutes as already described.
2. Remove the upper and lower horizontal bar

riers (4 and 5\ Fig. 22.

3. Remove the four bolts (3) at the mounting

flange of the rear bushing being removed
and lower the bushing assembly.

4. Referring to Fig. 20, disassemble the pri
mary contact springs (6) as previously de
,

moving mounting bolts (5).

Movable Primary Contacts (5), Fig. 21.
(1200 Amp. Breaker)
1. Remove the nuts from assembly bolts (6).
2. Remove the primary contacts and spacers
(not illustrated).
3. Reassemble in reverse order.

2. Remove the connection bar (9).
3. Remove the cup bearing (3).

6. Referring to Fig. 19, disassemble the con
tact support (4) and arc chute mounting

bracket (2) by removing two bolts (3).

7. Reassemble in the reverse order. The arc

chute mounting bracket (2) is not symmetri

cal and must be assembled correctly to ori
ent the arc chute properly on the breaker.

The longest projection of Uie bracket should
be toward the lower end of the bushing.

Front Bushing

4. Spread the contact arms (4) and remove

1. Open the breaker and remove the boxbarrier

5. Reassemble in the reverse order.

and arc chutes as already described.
2. Remove the upper and lower horizontal bar-

Contact Blade Assembly (4, 5. 7), Fig. 21.

biers (4 and 5^ Fig. 22.
3. Remove the connection bar (9), Fig. 21, and

2. Remove the cup bearing (3) and.the pin (2),

4. Remove the four bolts at the mountingflange

the primary contacts (5).

1. Remove the connection bar (^9).
Fig. 4.

3. When reassembling, first insert the piston
assembly (10), Fig. 21, into the booster-

cylinder and reassemble the cup bearing(3).

4. Replace pin (2), Fig. 4, and connection bar
(9). Fig. 21.
F.

1. Open the breaker and remove thebox barrier

5. Disassemble the spring retainer (4) by re

(2000 Amp. Breaker)
1. Remove the nuts from assembly bolts (6).

Rear Bushing

scribed.

Movable Arcing Contact (7), Fig. 21.
1. Remove the assembly bolts (8).
2. Reassemble in reverse order.

To replace the bushing, proceed as follows:

cup bearing (3).

of the front bushing being removed, and
lower the bushing.

5. When reassembling, first mount the bushing
and assemble the cup bearing (3) and con
tact arm (4), Fig. 21.
6. Check all contact adjustments as outlmed
under INSTALLATION, ADJUSTMENTS.

After disassembly and reassembly of any con
tacts, check all contact adjustments as de
scribed under INSTALLATION, ADJUSTMENTS.
...

BUSHINGS

IMPORTANT:

NOT

REMOVE

ALL SIX

BUSHINGS AT ONCE. The bushings have been care

fully aligned with the breaker frame, during assembly
at the factory, and it is important that this alignment
be maintained to facilitate installation of the break
er in the metal-clad unit. It is therefore recom

mended that the bushings be removed and reassem
bled one at a time. Also, before removing any one

bushing, measure the distance from that particular
bushing to adjacent bushings in both directions, so
that it may be re-installed in the same location.
It is also possible to remove and reassemble
three bushings at one time. If this is preferred,
alignment of the bushings may be accomplished by
placing the breaker in a de-energized spare metalclad unit before tightening the bushing mounting
bolts.

This must be done before the arc chutes

are re-installed.

4. Upper Horizontal Barrier

1. Front Bushing
2. Seer Bushing

5. bover Horizontal Barrier

3. Mounting Bolts

Fig. 22

Rear View of Breaker with One
Arc Chute Reoioved

GEH>2000

Magne-blast Circuit Breakers
4. Loosen the four nuts under the bottom plate
(4) approximately 1/2". Support the Iwttom
plate with a rope sling or hoist and remove
the two rear nuts.

5. Remove the nuts (8) at the top of the front

studs.
This permits the bottom plate,
closing coil, solenoid pot (1) and control
device plunger guide (9) to be removed.
6. To reassemble, first place the closing coil

and spacers on the bottom plate (4). Raise
into position, inserting the control device

plunger guide (9) and compressing the piston
ring on the upper pole piece.

7. Tilt the bottom plate downward and replace

the solenoid pot (1) and two front studs and
nuts (8).
8. Tighten the four nuts under the bottom plate
taking special precaution to center the clos

ing coil around the pole piece. If the closing
coil is not firmly held in place, add spacers
above the closing coil.

9. Replace the control device trip plunger (5)
and armature (6).
10. Recheck the mechanism adjustments as ex

plained under INSTALLATION, ADJUST
MENTS.

Solenoid Pot

Terminal Board

6. Closing Armature
7. Stop Nuts

3. Secondary Wire

8. Front Stud Nuts

9. Plunger Guide

Cleats

Bottom Plate

10. Closing Cbil Leads

5. Control Device Trip
Plunger Bod

Fia. 23

11.

Guide Studs

12. Stop Nuts

Closing Solenoid Assembly

CLOSING COIL

The closing coil is contained within the solenoid

pot (1), Fig. 23.

To remove the closing coil, pro

ceed as follows:
1.

1. Open the breaker.
2. Remove the two closing coil leads (10).
Remove the terminal board (2) from the
solenoid pot and let it hang by the wires.
Also, remove the wire cleat band (3).

3. Remove the stop nuts (7 and 12) on guide
studs (11), lower the armature plate (6)
and control device trip plunger (5). Note:
k

For ease in removing the closing coil and
bottom plate (step 5) the armature and
plunger assembly can be removed from the
mechanism by removing the four bolts on

the under side of the armature plate.

Pivot Pin

2. Opening Spring Unit
3. Pivot Pin

Fig. m

Opening Spring Assembly

TRIP COIL

To replace the potential trip coil (3), Fig. 25,
proceed as follows:

1. Open the breaker and remove the opening
spring unit (2), Fig. 24, by removing the
pivot pins (1 and 3).

Magne-blast Circuit Breakers GEH-2000
2. Disconnect the two trip coil lead wires (4),

Fig. 25.

3. Remove the two mounting bolts (2) and the
trip coil support (1).

4. Remove the trip coil (3).

5, After reassembling (in the reverse order)
check the primary contact gap ai^ustm^t
as explained under INSTALLATION, AD-

JUSTMENTS.

INTERLOCK SWITCH

^
r

To remove the interlock switch (3), Fig. 6,

remove the two mounting screws (4) and disconnect
the lead wires. Reassemble in the reverse order
and check the switch adjustments as explained under
INSTALLATION, ADJUSTMENTS.
LATCH CHECKING SWITCH

To remove the latch checking switch (6), Fig.
6, (when furnished), remove the two mountingscrews
(8) and disconnect the lead wires. Reassemble in
the reverse order and check the switch adjustments

as explainedunder INSTALLATION, ADJUSTMENTS.
CUT-OFF SWITCH

To remove the cut-off switch (1), Fig. 8, re-

move the two mounting bolts and disconnect the lead
wires. When reassembling, check the cut-off switch

adjustment as explained under INSTALLATION, AD

JUSTMENTS.

1. Trip Coil Support
2. Mounting Bolts

Fig. 25

3. Trip Coil

4. Trip Coil Loads

Potential Trip Coil

Magne-blast Circuit Breakers GEH-2000

RENEWAL PARTS

Note: The listed terms "right" and "left" apply when facing the solenoid mechanism end of the breaker.
ORDERING INSTRUCTIONS

1. ALWAYS SPECIFY THE COMPLETE NAMEPLATE DATA OF BOTH THE BREAKER AND THE MEQHA* NISM.

2 SPECIFY THE QUANTITY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF LISTED),
AND DESCRIPTION OF EAdH PART ORDERED, AND THIS BULLETIN NUMBER.

3 STANDARD HARDWARE, SUCH AS SCREWS, BOLTS, NUTS, WASHERS, ETC., IS NOT LISTED IN THIS
BULLETIN. SUCH ITEMS SHOULD BE PURCHASED LOCALLY.

4. FOR PRICES, REFER TO THE NEAREST OFFICE OF THE GENERAL ELECTRIC COMPANY.
ILLUSTRATION REFERENCE
Page

Control Device for All Mechanisms

Fig. 27
Fig. 38

Cross-sections - Type AM 2.4/4.16-3

Fig. 26

Impact Trip Device for All Mechanisms

Fig.

Interlock Plunger

Maintenance Closing Device

Fig. 31
Fig. 34

Movable Contact Arm Assembly

Fig. 29

MS-13 Mechanism - Cross-section, Details, Spring Asm.

Fig. 30

MS-13 Mechanism, Front View, Right and Left Side View
MS-13 Mechanism, with Current Trip. Partial View

Fig. 32
Fig. 35

Rear Bushing Assembly

Fig. 28

Secondary Disconnect Device and Mechanism Parts

Fig. 33

Undervoltage Device

Fig. 36

Arc Chute

• GEH-20i)0

Magne-blast Circuit Breakers
PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In the tabulation below are listed the parts of those breakers which are usually recommended for stock
for normal maintenance. Other parts are listed on the following pages.
FIG.
NO.

REF.
NO.

RATING
INMVA

RATING
IN AMPS

26
27
28
28
29
28
29
29
29
29
29
29
28
28
28
28
28
28
27
28
27
27

1
130
165
165
211
156
212
212
212
212
212
212

All
All
150
250
All
All

All
All

27
27

26
28
30

30
30
30
32
32
32
32
32
32
32

36
36
36
37
37
38
38
38

160
160
159
168
168
168
132
158
131
126
117
118
7
155

261
261
261
261
370
370
370
370
370
370
370
663
663
663
738
738

100/150
100/150
150/250
150/250
All
AU
150
250
All
150
150
250
250
All
All
250
All
All
All
All
250
150
250
150
All
All
All

All
All
All
All
All
All

All
All

600/1200
1200/2000
All
All

600/1200
600/1200
1200
1200
2000
2000

600/1200
1200/2000
All

600/1200
2000

1200/2000
All
All
All
All
All
All
AU
All
All
All
AU
AU
All
AU
AU
AU

CAT. NO. FOR TYPE

NO. PER

AM-4.16-(MVA)-3

BREAKER

263B293
258C616
236C791
236C791
6496488
236C790

P-2
P-9
P-8
P-8
P-3
G-5

6591644 P-7

6501644
6591644
6591644
6591644
6591644
414A180

P-8
P-7
P-8
P-7
P-8

6509787 P-1
6445087

6557243 P-1
6557243 P-2
6557243
258C616
414A116
421711
383A932
414A116

414A117
281B708

236C791
6375521
6375521
6375521
6375521
6174582
6174582
6174582

6174582

All
AU
AU
AU
All

6275070
6275070

All
All
All

6275017

6275070
6275017
6275017

P-2
P-6
P-4

P-1
P-2
P-1
G-4
G-1
G-2
G-6
G-1
G-2
G-1
G-2
G-14
G-10
G-1
G-2
G-3
G-19
G-20
G-33
G-2
G-6
G-19
G-20
G-33

753
753
753

All
All
All
All

AU
All

6174599
6174599
6275017
6275017
6275017

753

All

6275017 G-34

All

3
6
12
24
3
3
3
3
6
6
6
6
12
24
3
6
6

6
6
3
12
6
3
6
3
6
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

DESCRIPTION

Booster cylinder
Upper runner insulation
Primary contact finger
Primary contact finger
Movable arcing contact
Stationary arcing contact asm.
Primary contact mov.
Primary contact mov.
Primary contact mov.
Primaxy contact mov.
Primary contact mov.
Primary contact mov.
Primary contact finger spring
Primary contact finger spring
Buffer

Clamp for buffer
Clamp for buffer
Clamp for buffer
Lower barrier

Insulating plate
Insulating cup
Lower shield
Insulation

Upper insulation

(derating rod
Flex. Conn.

Closing coil (125 V.D.C.
Closing coil (125 V.D.C
Closing coil (250 V.D.C.
Closing coil (250 V.D.C.,
Potential trip coil (125 V.D.C

Potentiail trip coil (250 V.D.C.
Potential trip coil (230 V.A.C.

Potential trip coil (48 V.D.C '
Potential trip coil (24 V.D.C.
Potential trip coil (48 V.D.C,
Potential trip coil (32 V.D.C.

UVD Coil (125 V.D.C.)
UVD Coil (250 V.D.C.)

UVD Coil (230 V.A.C.)
Current trip coil (3 Amp. A.C.)
Capacitor trip coil (230 V.A.C.)

Control device coil (125 V.D.C.)
Control device coil (250 V.D.C.)
Control device coil (230 V.A.C.
cont.)
Control device coil (230 V.A.C.
int.)

Magne-blast Circuit Breakers GEH-2000
PARTS REFERENCED IN FIG. 26 FOR ALL RATINGS
REF.
NO.

1
2
3
4
5
6
7
8
8
g
9
9
11
12
13
13
15
15
18

19
19
20
21

22
23

MVA.

AMPS.

All

AU
All
All
AU
AU
All
AU

All
All
All
All
All
All
All
All
All
All
AU
AU
All
All
All
All
AU
AU

AU
AU
AU
AU

All
All

24
25
26

All

28
29
30

AU
All
All
AU
AU

31
«

AU
AU

CAT. NO. FOR

NO.

AM-4.16-(MVA)-3

REQ.

600/1200
2000

263B293
236C789
258C614
258C619
258C614
9915623

P-2
G-1
P-13
G-3
P-4

G-1
281B708 G-4
258C614 P-6
258C614 P-7

2000
AU

G-2
G-3
G-1
P-8
P-5
G-3
G-2
P-20
6592511 P-1
258C683 G-1

236C767 G-7

236C767 G-9
236C767 G-8

1200
2000
600
AU
AU

600/1200
2000

600/1200

All
AU
2000
2000
2000
2000
2000
AU

600/1200
600/1200
600/1200
600/1200
All

258C613
258C613
258C613
258C619
258C614
258C614
258C614
258C614

6597296 P-B
6442246 P-1

6441630
6442257
369A407
6442258
6441617
414A106

P-1
P-1
P-1
P-1
P-1
P-4

6591812 P-6
6509700 P-1
6442317 P-1
258C672 G-1

3
1
2
3
3
3
3

6
6
3
3
3
3
3
3
3
4
1
1
1
1
2
2
6
3
3
3
3
3
3
3
3
3
1

DESCRIPTION

Booster cylinder
Box barrier assembly
Barrier support
Arc chute clamp
Arc chute support
Vertical barrier front

Operating rod
Horizontal barrier upper
Horizontal barrier upper

Bushing (long
Bushing (long

Bushing (long

Connection bar
Block

Horizontal barriers (lower)

Horizontal barriers (lower)
Plate

Top plate
Wheel assembly complete

(front & rear)

Wheel base
Wheel base
Rear wheel
Rear wheel
Spacer

& wheels
& wheels

asm. complete
and bushing

Washer

Bearing
Spring
Stud
Washer
Screw

Spacer

^ring
Bearing
Mech. covers

Standard breakers have 1-16 point secondary disconnect device.

Interchangeable breakers have 2-seven point secondary disconnect

devices.

See cover photograph.

GEH-2000

Magne-blast Circuit Breakers

#
O)
00

to
CO

SECTIONS AA
• j 'M

I&3

P -!S|I

kCO

ibi

m
t
re4 166

Fig. 26A

P5»

166

Fig. 28B

Front View

Fig. 28

136

le?

:63

isa

IS5

Fig. 280

Component Parts

Back View

Rear Bushing Assembly (Ref. Ho. 150)

PARTS REFERENCED IN FIGS. 28A, 28B & 28C FOR ALL RATINGS
RFT
rvcax •

MVA.

NO.

AMPS.

CAT. NO. FOR

AM-4.16-(MVA)-3

REQ,

150
150

600

236C790 G-i

150/150A

1200

150

250/250A

1200

150
151

250/250A

2000

236C790 G-2
236C790 G-3
236C790 G-4

150/250

1200
2000
600

258C612 G-2

600/1200
1200/2000

6592330 P-2

150A

151
151
152

250
150
150

152

250

150/250

153

3
3
3
3
3
3
3
3
3
3
3
3
6
3
3
3
12
24
12
24

258C612 G-3
258C612 G-1
6592331 P-2
236C791 P-9

600/1200

DESCRIPTION

Rear bushing assembly
Rear bushing assembly
Rear bushing assembly

Rear bushing assembly
Rear bushing
Rear bushing
Rear bushing
Spring retainer
Spring retainer
Support
Support
Arcing contact support

153

250

2000

154

All
All

236C791 G-3
236C791 G-1

All
All
All

236C790 G-5

159

All
All
All
All
All

160

150

160
161
161

160

600/1200
1200/2000
600/1200

236C790 P-2Z

250

1200/2000

236C790 P-22

162

150

600/1200

Nar Wash 1/2-20

Spring
Spring
Spring guide
Spring guide
Washer for spring guide

162

250
All

1200/2000

j Nar Wash 1/4-20

Washer for spring guide

150
250

600/1200

155
156

158

250

163
164
164

164
165
165
166
166

166

167
168
168
168

250
!50

;

250

150

'
1

250
250

150
150
250

2360791 P-19

414A116 P-4

6445087
414A180
6509787 P-1

175V557 P-1

All

1200
2000

258CG66P-1

! 258C666 P-3
!

3
3
12

258C666 F-2

600/1200

1 236C791 P-8

1200,'2000
600, 1200

236C791P-8
2580666 P-5

1200

23GC79] P-20

2000

236C791 P-3

24
3
3
0

1200

j 258C666 P-4

600/1200

1 6557243 P-1

2000
1200/2000

1 6557243 P-2

j 6557243 P-2

Flex. conn.

Arcing contact asm.
Insulating plate
Buffer

Lock plate

Contact support

Contact finger
Contact finger
Primary contact finger retainer

Primary contact finger retainer
Priinarv contact finger rc-tainer

Spacer "

Clamp ICi.'- buffer
: Clamp 'or buffer

! Clamp for buffer

Fig. 29A

214 217-218 219

215 219 221

217-218 215

For 2000 Amp. Breakers,

Fig. 29E

For 1200 Amp. 150/250
MVA Ratings

AII Ratings

Fig. 29

Fig. 290
For 600 and 1200 Amp
lOO/iSO MVA Ratings

Movable Contact Arm Assembly

PARTS REFERENCED IN FIGS. 29A, 29B & 29C
CAT, NO. FOR

REF.

AMPS

AM-4.]6-(MVA)-3

100/150

600/1200

236C792 G-5

100/250

2000
1200

236C792 G-6

600/1200

6496488 P-3
6496488 P-3
5496488 P-3

NO.

150/250
100/150
150/250
100/250
100/150

150/250
100/250
150/150

150/250

100/250
All
All
All
All
All
All
All
All

2000
1200

600/1200
1200
2000

600 1200
1200
2000
All

All
2000
All
-All
-All
-Ail
2000

236C792 G-7

6591644
6591644
6591644
6591644
6591644
6591644
258C666
236C792
258C666
236C792
236C:92
4HA146
414Ai46

P-7
P-7
I-7
P-8
P-8
P-8
P-:
G-8
r-6
P-22
1 -3
P-4
P-3

258C619 r-2

NO. REQ.
3
3
3
3

DESCRIPTION
Movable contact arm assembly
Movable contact arm assembly
Movable contact arm assembly
i Movable arcing contact

I Movable arcing contact

3
3

I Movable arcing contact
I Movable primary contact

; Movable primary contact

6
3
6

Movable primary contact
Movable primary contact
: Movable primary contact

I Movable primary contact

' Contact arm

Tulje & piston assembly

Contact arm

3
3
12
0

: Piston ring
Piston ring e.\pander
, Flex nut
Flex nut

Spacer

GEH-206o Magne-biast Circuit Breathers

%
250

.268

oo
00
-•

(SEE VIEWS)

(SEE VIEWC)
(SEE VIEW D)
254

260

(SEE VIEW F)

(SEE VIEW

264 A

264
263A

P
00
00
to

265

o
00
ir>

YP7777?///////77777;',
CO

o
CO

Fig. 30A

Cross-section

Fig. SOB

Complete Spring Assembly

302

253'

263 U284

2£a

ij 263

299

292

VIEW D

VIEW A

253

298303

288-

:fc

30^

300

Vifiw E

285
286

287-

Vi£W G

VIEW 8
O

29n

/-25:

289-

VIEW

Fig. 30C

Fig. 30
32

iJetaileti Vieni

ws-i3 Mt-c!.ar.i sit u.r /,v J .i.-,F-;

Magne-blast Circuit Breakers

GEH-2000

PARTS REFERENCED IN FIGS. 30A, SOB & 30C FOR ALL RATINGS
REF.
NO.
250
251
252
253
254
255
256
257
258

259
260
261
261
261
261
262
262
263
263
264
264
264A
264A
265
266
267
268
269
270
271
272
273
274
275
276

277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
299
301
302

303
304
305
306

CAT. NO. FOR

AM-4.16-(MVA)-3
6443518
258C608
258C608
258C608
258C608
6551742
258C604
6192382
258C608
281B711
258C609
6375521
6375521
6375521
6375521
236C796
236C796
6591632
6591632
236C795
236C795
236C796
236C795

P-2
P-6
P-7
P-1
P-5

414A109
236C796
236C796
383A926

P-4
G-2
P-8
AE P-1

P-8
AB P-1
P-2
G-1

P-1
G-2
G-6

G-1
G-5
P-5
P-6
P-1
P-2
P-4
P-45
P-14
P-23

258C630 P-7
258C630 P-6
258C630 P-8
414A109 P-2
258C630 G-1
369A411
369A468

258C630
258C630
258C630
383A926
258C630
258C611
258C611
414A111
6508765
6370566
258C609
258C608
258C611
414A110
414A112
215D470
6509799

P-3
P-5
P-4
AF P-20
P-9
P-1
P-11
P-1
P-75
P-5
P-4
P-3
P-1
P-1
P-18

414A110 P-3
6477094

414A193
383A926
215D470
258C608
258C611

P-5
AF P-41
P-25
P-3
P-5

NO. PER
MECHANISM
1
1

DESCRIPTION

Shaft
Crank
Latch

Crank
1
1
1
1
1
1
1
1
1
1
1
1
1

Link

Spring
Spring clip
Veeder counter
Link

Indicator assembly
Prop

Closing coil (125 V.D.C.) 250 MVA.

Closing coil (125 V.D.C.) 150MVA.
Closing coil (250 V.D.C.) 250 MVA.
Closing coil (250 V.D.C.) 150 MVA.
Plunger (AM-4.16-250)

Plunger (AM-4.16-150)

Piston ring (AM-4.16-150 & 250)

1
1
1
1

Piston ring (AM-4.16-150)
Pole piece (AM-4.16-250)
Pole piece (AM-4.16-150)
Guide for pole piece (AM-4.16-150)

Guide for pole piece (AM-4.16-250)

1
1

Washer

Arm plate
Stud

1
1
1
1

Pin
Clevis
Plate

Complete spring assembly
Inner spring
Outer spring
Spring retainer
Retaining plate
Spring base

Rod

Buffer
1
1
1
1
1
1
1
1
1

Pin
Bracket
Latch shaft

Stop bar

Trip shaft bearing
1
1
1

Spring
Bushing
Roller

Link
1
1
1

1
1
1
1

Prop pin
Pin

Trip roller bearing
Spacer
Spring
Pin

Prop spring
Pin
Pin

Spacer
Latch guide

258C609 P-9

1
1
1

Pin
Pin

215D470 P-29
258C607 P-6
383A926 AE P-39

1
1

Roller
Pin

Spacer

- GEH-2000

Magne-blast Circuit Breakers

326

328

o
to
CO

c^l

329

VIEW AA
00

Fig. 3IA

Fig. 316

Early Design

Present Design

&
to

CO
•o
CO
CO

326

•

Fig. 3IC
Fig. 31

Present Design
Interlock Plunger

PARTS REFERENCED IN FIGS. 31A, 31B & 310 FOR ALL RATINGS
REF.

NO.
325
326
327
328
329
^ 330

331

CATALOG NO. FOR TYPE

AM-4.16-(MVA)-3 ^
6442255
264B133
6509728
6477427
6443714
6477427
6597228

P-1
G-1
P-1
AA P-9
JA P-4
P-1

AM-4.16-(MVA)-3 0
236C787
236C787
6509728
383A926
236C787
236C787
236C787

P-12
G-2
P-1
AD P-1
P-14
P-5
P-16

NO. PER
MECHANISM
1
1
1
1
1
1
2

DESCRIPTION

Plunger for interlock
Bracket for interlock

Spring for interlock
Pin
Roller
Pin

Crank

A This plunger interlock frame is wider than the mechanism frame.

0 This plunger interlock frame is narrower than the mechanism frame.

Fig. 32A

Fig. 32B

Right Side View

Fig. 32

HS-i3

Fig. 32C

Front View

Left Side View

Mechanism for Type AH 2.4/i». 16 Breaker

PARTS REFERENCED IN FIGS. 32A, 32B & 32C FOR ALL RATINGS
CAT. NO. TYPE

REF. NO

AM-4.16-(MVA)-3
258C604 G-3
258C604 P-2

236C795 P-40
174V394
6445059
258C608 P-6

NO. PER
MECHANISM

DESCRIPTION

Man. trip rod
Man. trip rod support
Rod
Tube

Insulating tube
Crank

6578509 G-2

Aux. Sw.

258C608 P-1
215D470 P-43

Crank

236C788 P-6

414A190
236C788 P-3
258C601 G-3
258C601 P-14

236C788 F-8
236C788 P-7
258C601 P-16

236C788 P-30
6351353 P-41
6351353 P-41
6174582 G-1

6174582
6174582
6174582
6275070
6275070
6275070

G-2
G-10
G-14
G-1
G-2
G-3

Spacer
Interlock prop shaft
Spring
Interlock prop
Bearing bracket
Shaft
Link
Crank

Crank
Bracket

Latch checking switch
Interlock switch

Potential trip coil (125 V. D.C.)
Potential trip coil (250 V, D.C.)

Potential trip coil ( 48 V.
Potential trip coil (220 V,
Potential trip coil ( 24 V.

Potential trip coil ( 48 V,
Potential trip coil ( 32 V,

GEH-2000

Magne-blast Circuit Breakers

• V

« i)
V

-('i ?

'^:j

Fig. 33

Secondary Disconnecting Device And

Fig. Sii

Maintenance Closing Device

Mechanism Parts For AH Types

FARTS REFERENCED IN FIGS. 33 & 34 FOR ALL RATINGS
CAT. NO. FOR TYPE

AM-4.16-(MVA)-3
264B162
264B173
366A234
6319964
6046942
848768

G-1
G-1
P-1
P-2

NO. PER
MECHANISM

DESCRIPTION

Secondary disc, device, complete: 16 point
7 point

Secondary disc, device, complete:
Contact nut

Plug

Nut for plug
P-1

Lock washer for plug

6443717

Stud

6505244 P-1

Socket
Shim

6557827 P-1
258C669 G-1

Maintenance closing device

i-"

Magne-blast Circuit Breakers GEH-2000

Fig. 35 Partial View of MS-13 Mechanism with
Current Trip (For Details, See Fig. l)

Fig. 36

Undervoltage Device (Ref. 647)

PARTS REFERENCED IN FIGS. 35 & 36 FOR ALL RATINGS
REF.
NO.

CAT. NO. FOR TYPE

NO. PER

AM-4.16-(MVA)-3

MECHANISM

6551725

366A611
6558748 P-1

DESCRIPTION

Spring
Trip pan
Bracket

6558756 P-1
6477418 AA P-10
366A600 P-1
6076401 P-307
6477427 AA P-B

Trip latch
Ball bearing
Trip arm

6556276 G-B5
9915617 AA

Terminal board

157V574

Stop for DC only

369A443

Spring for DC only
Spring for AC only

6551726
175V578

6076401 P-309
6076401 P-305

Pin
Pin

Undervoltage device complete

Pin for DC only
Pin for AC only
Pin

6418069 G-6

Switch

175V576
374A246 F-1

Pin
Bracket

175V562 P-1
384A330 G-1

Shim for DC only

6477414 AC I'-20

Stud

6558711 P-1
6558723 G-1
6509798
6275017
6275017

Spring
Coil (125 V.D.C.)

6275017

Link arm assembly for DC only
Coupling
Trip arm

Coil (230 V.A.C.)
Coil (250 V.D.C.)

GEH-2ower Check •••

5
5
5

9
10
10
10
10

OPERATION•••••••••
CLOSING OPERATION. ••••••
OPENING OPERATION, ••••••
TRIP FREE OPERATION •••••

11
11
16
16

..........
. ... .
MAINTENANCE, •••••••
.
.
.
PERIODIC INSPECTION. •
•••••••
Arc Chutes
Breaker Contacts •
. . . . .. . . .
llechanlsin• • • • • • • • • • • • • •
..
Bushings and Insulation•
LUBRICATION • •••••••••
Method of Cleaning Bearings •
TROUBLE SBOat'JNG ••••••
Failure to Trip ••••••• •
Failure to Close or Latch Closed,
Overheating • • • ·. • • • • • • . .

. .

RENEWAL PARTS ••••••••
RECOMMENDATIONS ••••
ORDERmG INSTRUCTIONS ••••• •

....
.....

•
REPAIR AND REPLACEMENT
Arc Chutes and Lower Arc RWU1ers
Conta.cts • • • • • •
Bushings•••
Closing Coil
'•
Trip Coll. •••••••
Latch Checking Switch
Cut-off Switch •••••

. .. .. .. . . .. .

.....

. . .· .

('·

7
7
8

8
8

9
9

16
16
16
17
17
17
17
18
18
18
18
19
19
19
19
20
21
22
22
22

23
23
23

-i.a
..:
8

MAGNE-BLAST CIRCUIT BREAKERS

TYPE AM-2.4/4.16 WITH MS-13 MECHANISM
INTRODUCTION
The Magne-blast Circuit Breaker is designed
for installation in vertical-lift metal-clad switchgear, to provide reliable control and protection of

power station equipment. Among the many ad
vantages of metal-clad switchgear are added pro
tection to equipmoit and personnel, compactness,
simplified installation and reduced maintmiance.

In keeping with these features the Magne-blast

breakers are designed for interchangeability
and manueverability, together with reliaJ^ty and
low maintenance requirements.

TheAM-2.4/4.16Mhgne-blast Breaker is avail
able in a number of current and voltage ratings. Re
fer tothe breaker nameplate for the complete rating
information of any particular breaker. The shon
circuit conditions to be imposed on the breaker must
not exceed its rating, nor should it be called upon to
operate at voltages or currents greater than those

gven on the nameplate. Since this book is wrMen

cover several ratings of breakers that are of
the same general design, all instructions will be of

a general character and all illustrations will be

The Magne-blast Circuit Breaker operates on
the principle that an arc can be interrupted in air
by sufficiently elongating and cooling it. This is
accomplished by means of a strong magnetic
that lengthens the arc and forces it into intimate

contact with cool dielectric material. A sturdy,
reliable operating mechanism assures low mainte
nance and long life, and the use of flame-retardant
materials reduces fire hazards to a minimum

typical, unless otherwise specified.

PROPER INSTALLATION AND MAINTENANCE

ARE NECESSARY TO INSURE CONTINUED SATIS
FACTORY OPERATION OF THE BREAKER . The

following instructions will provide complete Infor
mation for placing the magne-blast breaker in ser
vice and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
RECEIVING AND HANDLING
Each breaker is carefully inspected and packed
Iqrworkmen experienced in the proper fcanHiing and
packing of electrical equipment. Immediately upon
receipted the circuit breaker, an examination should
be made for any damage sustained in transit. If

this is not possible, the following precautions must
be taken to insure the proper storage of the breaker:

1. The breaker should be carefully protected
against condensation, preferably I7 storing
it in a warm dry room, since water ateorption has an adverse euect on the insulation
parts. Circuit breakers for outdoor metal-

injury or rough ladlingis evident, a damage claim

clad switchgear should be stored in the
equipment only when power is available and

should be filM immediately with the transportation
company and the nearest General Electric Sales
Office should be notified.

the heaters are in (deration to prevent con
densation.

2. The breaker should be stored in a clean

location, free from corrosive gases or
fumes; particular care should be taken to
protect the eqvipment from moisture and
cement dust, as this combination has a very
corrosive effect on many parts.

It is mqiected that due care will be exercised

duringthe unpacking and installation of the breaker

so that no damage will occur from careless or rough

handling, or from e:q>osure to moisture or dirt. A
nail puller should be used to open the crates, and
cture should be exercised to prevent tools from
striking either the crate en-any part of the breaker.

3. Machined parts ofthe operating mechanism,

etc., should be coated with a heavy oil or
grease to prevent rusting.

Loose parts associated with the breaker are always

included in the same crate. Check all parts against
the packing list to be sure that no parts have been
overlooked.

If the breaker is stored for any length of time,
it should be inspected periodically to see that rust

ing has not started and to insure good mechanical

STORAGE

condition. Should the breaker be stored under un

It is recommended that the breaker be put into
service immediately in its permanent location. If

favorable atmospheric conditions, steps should be
taken to dry out the breaker before it is placed in
service.

"!!
in nqvipn,^
nor further
to provide
for every
'ndo/lalfon,
operation or maintenance.
StH>M
information
bepossible
desired

GEH-1804

1.
2.
3.
4.

Magne-blast Circuit Breakers Type AM

Plunger Interlock
Secondary Coupler
Auxiliary Saiteh
Opening Spring Unit

5. Uanusl Trip

W '0'

6. Control Device

7. Closing Solenoid
6. Gosing Araature

9. Cbntrol Device Plunger

Type HS»i3C Operating Hechanien

DESCRIPTION
The magne-blast breaker is composed of two
major parts, the breaker element and the operating
mechanism. The breaker element comprises three

similar pole units, each pole unit consisting of
main and arcing contacts, an interrupter, and an
enclosing box barrier that segregates the inter
rupting units from each other to provide insulation
between phases as well as from each phase to
ground. The primary connections to the associated

metal-clad equipment are made through the pri
mary disconnect studs.

The MS-13C operating mechanism shown in
Fig. 1 is of the solenoid type designed to give high
speed closing and opening. The closing operation
is controlled by the control device (6). This device

also permits trip free operation (tripping the breaker
at any time during the closing operation), and pre
vents solenoid pumping (reclosing) after a trip free
operation. For AC closing operation, two copperoxide rectifiers, mounted elsewhere in the metalclad unit, are used to supply the direct current on
which the closing coil operates. The breaker can

be opened electrically, by remote control, or manu
ally, Iw means of the manual trip device (5). All

seconcUry connections from the breaker to the

metal-clad unit are made through the coupler (2).

Aplunger interlock (1), Fig. 1, is used where it
is desirable to prevent having two adjacent breakers
closed at the same time, or it can be used to operate

an auxiliary switch mounted in the metal-clad unit.

A metal-clad interlock is provided to prevent the
breaker from being raised in the metal-clad unit

while in the closed position, and to block the breaker
open until it is completely raised. It is also used
to prevent the breaker from being lowered while in
the closed position.

The MS-13F operating mechanism, differs

somewhatfromtheMS-i3Cbut its operation is prin
cipally the same. On this mechanism a cut-off switch

and relay arrangement is used in place of the con

trol device, and it has two secondary couplers in
stead of one. Also, instead of the metal-clad inter

lock, the MS-13F mechanism has a trip interlock,

which trips the breaker when any attempt is made
to install or remove the breaker from the Metal-

clad unit when in the closed position. A fork-type

lever can be furnishedtooperate an auxiliary switch
in the metal-clad unit. For a detailed explanation
oftheoperationof the breaker and mechanism refer

to the section OPERATION.

Magne-blast Circuit Breakers Type AM

1.Closing Armature

3. Handle

2.Maintenance Operating Device

4. Belease Valve

Fig. 2

GEH-1804

Method Of Mounting Maintenance Operating Device

INSTALLATION
The following instructions explain the necessary

to the left, the closing armature will return to its

steps to be taken before the breaker is placed in the

normal position. Electrical operation must not be

metal-clad unit. This includes a complete check of

attempted until the breaker has been operated
manually through itscomplete stroke several times
andfinalinstallation Inspectionhas been completed.

all of the breaker adjustments, in addition to a
thorough inspection. For final installation instruc

tions refer tothe Metal-Clad Switchgear instruction
book. Reference should also be made to the connec

tion diagram that is furnished with each unit.
CAUTION:

Do not work on either the breaker or

the mechanism while in the closed position unless

the prop and trip latch have been securely wired or
blocked to prevent accidental tripping.
ADJUSTMENTS

Although the breaker has been completely ad
justed and tested at the factory, it is possible that

unusually rough handling during transportation may
have caused some loosening or disturbance ctf parts
oftheapparatus. It is therefore advisable to review
all adjustments before placing the breaker in ser

vice, making readjustments wherever necessary.
A maintenance operating device Is provided for
operation of the breaker during these adjustment

checks. Mount the device as shown in Fig. 2, and
turn the release valve (4) firmly to the right. To
close the breaker, operate the handle (3) with a

pumping motion. By turning the release valve (4)

All adjustments should be checked not only
during the initial installation of the breaker but also
during periodic inspections andwhenever it becomes
necessary to repair or replace parts that have be
come worn or defective while In service. The

following adjustments are listed in the order in

which they are to be checked. First, however, re
move the breaker from the metal-clad unit and
remove the box barrier and the mechanism cover.

PRIMARY CONTACT WIPE

When the breaker is closed, as shown in Fig.3,

the primary contacts (1) should rise 5/16"+0-1/16".
To obtain this adjustment open the breaker and, re
ferring to Fig. 4, loosen the check nut (8) and turn
the jam nut (7).
Screwing up on the jam nut
will decrease the primary contact wipe, down will
increaseit. Tighten the check nut, close the breaker
and recheck the wipe. With the primary contact
wipe correctly adjusted, the clearance between the
contact blade (4) and the buffer block (1) should

be 1/16" or greater, when thebreaker is fully closed.

GEH-1804 Mafoie-blast Circolt Breakers Type AM

Prtaary Contact Mipe

Arcing Contact Wipe

1. Stationary Primary Contacts
2. Uovsble Primary Contacts
3. Buffer Block

4. Stationary Arcing Contacts
5. Movable Arcing Contacts
6. Coil Protector
7. Arc Bunner

Fig. 9

Contact Adjustnents

ARCING CONTACT WIPE

Refer to Fig. 3. Close the breaker until the
arcing contacts just touch. This can be determine

with the use of a circuit continuity tester such as a

light indication or bell set. In this position, the gap
between theprimarycontact fingers (l)and the mov
able primary contact (2) should be 5/18" or greater.
This setting has been made in the factory and no
adjustment is provided. A wipe of less than 5/lff'
is usually an indication that the arcing contacts

need to be replaced. When making this check, also

see that the movable arcing contact (5) passes
through the slot in the upper arc runner (7) without
touching.
PRIMARY CONTACT GAP

Refer to Fig. 4. Press the manual trip button

3. Stationary Primary Contacts
3. Movable Primary Contacts

allowing the breaker to trip open normally. Do not
force the contacts open wider by hand. The gap
between the stationary primary contact (2) and the

4. Contact Arm

movable primary contact (3) should be 3-13/16" +

1. Buffer Block

5. Movable Arcing Contact
6. Pin

7. Jam Nut
8. Oiedc Nut

Adjustable Coupling For Making Primary
Contact Wipe Adjustment

1/8" - 1/16". To obtain this adjustment, first open

the breaker. Referring now to Fig. 5, loosen the
clevis bolt (8) and turn the adjustable stud (9) of the
opening spring housing (11). Unscrewing the cap
ydll decrease the primary contact gap. Aifter mak
ing the adjustment, close and trip the breaker and
measure the gap once more. If correct, tighten
the clevis bolt (8).

Magne-blast Circuit Breakers Type AM GEH-1804

V77TA

9. Adjustable Stud

1. Plunger Interlock

17. Closing Plunger

2. Main Craric

10. Closing Pin

3. Trip Shaft

11. Opening Spring Bousing

4. Trip Latch
5. Trip Latch Stop
S. Trip Koller

12. Opening Spring, Inner

19.

13. I^ening ^ring. Outer

20.

14. Closing Boiler
15. Prop
16. Closing Coil

21. Closing Armature
22. Stop Nuts
23. Amature Guide Belts

7. Position Indicator
8. aevis

Fig. 5

Rod

18. Piston Ring
Set Screw
Shins

Cross Section Of MS-13 Mechanism

TRIP LATCH WIPE

Refer to Fig. 5. The wipe of the trip latch (4)

on the trip roller (6) should be from 3/Iff' to 1/4".
This can be measured ^ putting a film of grease

on the latch (4), closing the breaker part way, and

tripping. The mechanism has the proper trip latch
wipe when the latch rests against the stop pin (5).

Noadjustment is provided andfa visual inspection is
usually all that is required. If this setting is not

correct look for insufficient travel of the trip sh^t
(3).

PROP CLEARANCE

Refer to Fig. 5. With the breaker closed as far

as possible with the maintenance device, the clear**
ance between the closing pin (10) and the prop (15)

should be 1/32" to 3/32". Measure the prop clear

ance with a feeler gage to determine whether or not
an adjustment should be made, and if so, exactly
how much adjustment will be required. To make

the adjustment, it will first be necessary to open
the breaker and remove the maintenance .operating

device. Then remove the two stop nuts (22) being
careful not to drop the armatur? (21). Remove the

CAUTION: When working on the mechanism in the

armature froui the breaker. Remove the two set

as accidental tripping can cause severe injury.

screws (19) and the closing plunger (17) from the
armature. Add or subtract the necessary thickness

closed position, keep fingers clear of the linkage,

GEH-1804

Magne-blast Circuit Breakers l^pe AM

of shims (20) to givethe required adjustment, then
replace the closingplunger, screwing it down a^inst

the shims. Using a small drill, spot the closing
plunger through the set screw hole. Replace the

set screws. To remount the armature on the

breaker, compress the piston ring (18). After
reassembly, remount the maintenance closing de

vice and check the adjustment.

This is the wipe, and should measure not less than

1/32". Let the trip shaft (3)returnto normal, then

press the plunger (2) in as far as it will go. This

additional motion is the overtravel and should be

not more than 1/32". The point of contact can be
determined with a light indication or bell set. To
change these settings it is only necessary to in
crease or decrease the number of washers (1).

CLOSING PLUNGER CLEARANCE

Refer to Fig. 5. With the breaker in the open
position, the clearance between the closing plunger
(17) and the closing roller (14) should be 1/lPto
3/16". To obtain this clearance, the nut (22) on the
two armature guide bolts (23) may be raised or
lowered.

Both nuts should be moved the same

amount. After making an adjustment, close and
openthe breaker and recheck the plunger clearance.
Repeat the adjustment if necessary.

1. Cut-off Switch

2. Switch Plunger
3. Adjusting Bolt
4. Washers
5. Lever Am
6. Washers

7. Adjustment Screw

8. Plunger Guide

Fig. 7
1. Washers
2. Switch Plunger

3. Trip Shaft
4. Latch Qiecking Switch

Cut-off Switch Adjustmeflti

CUT-OFF SWITCH ADJUSTMENTS

(AM-2.4/4.16-100/150A-1, -150/250A-1)
Fig. 6

latch Checking Switch Wipe

LATCH CHECKING SWITCH WIPE

Refer to Fig. 7. With the breaker in the open
position, the clearance between the switch plunger

and the adjusting screw is obtained by pushing the
switch plunger (2) in as far as it will go. In this

Referring to Fig. 6, first rotate the trip shaft
(3) manually clockwise toreleasethe switch plunger
(2). Then, allowing the trip shaft to return to the
reset position (counterclockwise), measure the

pt«ition the clearance between the switch plunger

travel of the switchplunger after the contacts make.

number of washers (4).

(2) and theadjustment screw (3)should be not more
than 1/32". This can be obtained by changing the

Magne-blast Circuit Breakers Type AM GEH-1804

1. Front Ditoonnect Stud
2. Interlock Bolt
3. Washers

4.
5.
6.
7.

Qmnecting Rod
Reset Plate
Reset Roller
Main OperatinE Shaft

13. Elevating Bar '
14. Iiig>act Trip Plate
is. Trip Latch
16. Trip Roller
17. Trip Armatuce
18. Trip Lever
19. IMdervoltage Trip

6. Reset Arm

9.
10.
11.
12.

Fig. 8

Trip Plate
Spring
Trip Boit
Clevis

Haoxner

Adjusting Rod
Manual Trip Button
Trip Setting Plate
Undervoltage Device

Adiustnents On Current Trip Device and Undervoltage Trio Device,
Shown With The Breaker In The Closed Position

IMPACT TRIP, CURRENT TRIR CAPACITOR
TRIP, AND UNDERVOLTAGE TRIP DEVICES
Fig. 8 shows the necessary settings that are
to be checked when these devices are furnished.

The amount of wipe between the trip roller (16)

and the trip latch (15) should be 3/32" to 5/32".
This can be altered by changing the number of shims

under the block against which the trip pan (14) stops.

In order to trip properly, the clearance be
tween the trip bolt (11) and the trip plate (9) should

be 1/32" to 1/16". This can be altered by releasing

the check nut and screwing the trip bolt (11) in or
out of the reset arm (8).
When an undervoltage device is furnished, check
the clearance between the trip hammer (19) and the

trip pan (14), with the undervoltage coil energized.

This clearance should be 1/32" to 1/16", and can be
altered by removing the connecting pin at either

end of the adjusting rod assembly (20), and turning
the clevis at that end.

20.
21.
22.
23.

After checking all the mechanical adjustments
as outlined above, operate the devices manually to
make certain that they trip and reset properly.
PLUNGER INTERLOCK

(AM-2.4/4.16-100/150-1 and 150/250-1)
Refer to Fig. 8. With the breaker in the open

position, the vertical distance "A" from the top of
the interlock bolt (2) to the bottom of the elevating
bar (13) should be 15 19/32" ± 1/16". To change
this adjustment add or remove washers (3).
AUXILIARY SWITCH LINKAGE

(Furnished Special on AM-2.4/4.16-100/150A-1 and
-150/250A-1).
Refer to Fig. 9. With the breaker in the open

position, the distance from the center line of the
front bushings (1) to the center of the slot in the

fork lever (2) should be 12 9/32", as shown. To
change this setting, loosen the locking bolts (3) and
move the fork lever in the proper direction. Tighten
the lock bolts.
9

GEH-1804

Magne-blast Circuit Breakers Type AM

FINAL INSPECTION AND TEST
1. For ease in reviewing the adjustments, the

6. See that anyplace where the surface of the paint

has been damaged during installation is repainted

immediately.

following are recapitulated:

a. Primary contact wipe: 5/16" + 0 - 1/16".

b. Arcing contact wipe: 5/16" or greater.
c. Primary contact gap: 3 13/16" + 1/8"
- 3/lff'.

HI-POTENTIAL TEST

If the breaker had been stored for a long period
of tim& it is recommended that the insulation be

d. Trip latch wipe: 3/19' to 1/4" with trip

checkeabefore the breaker is placed in service, A
standard 60 cycle high potentiu test at 14,000 volts

latch resting against stop pin.
e. Prop clearance: 1/16" + 1/32".

RMS will normally indicate whether the breaker is
satisfactory for service, itriththe breaker contacts

f. Closing plunger clearance: 1/16" to 3/16".
g. Latch checking switch overtravel: 1/32"

to each terminal of the breuer individuaUy for one

maximum.

h. Cut-off switch overtravel: 1/32" maximum.

i. impact trip roller wipe: 1/8"+1/32".
j. Impact trip bolt clearance: 3/64" + 1/64".
k. Undervoltage trip hammer clearance: 3/64"
± 1/64".

1. Plunger interlock (100/150-1 and 150/250-1):
15 19/32" + 1/18".
m. Auxiliary switch linkage (100/150A-1 and
150/250A-1. 12 9/32".

2. Check all nuts, washers, bolts, cotter pins, and
terminal connections for tightness.
3. bispect all wiring to make sure that no damage

has resulted du^g installation, and test for

possible grounds or short circuits.

4. See that all bearing surfaces of the mechanism
have been lubricated. Refer to the section on
LUBRICATION.

5. Operatethe breaker slowly with the maintenance
closing device and note that there is no excessive
binding or friction and that the breaker can be

moved to the fully opened and fully closed posi

in the fully opened position, apply the high p(^ential

minute with all other terminals and the breaker

frame grounded. After high potential tests are made
on organic insulating materials, these materials
should be inspected for visible leakage current
paths, and necessary action must be taken to replace

insulation that may havebeen ^ected by moisture

absorption. The high potential test is also recom
mended for breakers wliich have been removed

from service and stored over an extended period of
time under unfavorable atmospheric conditions,
AUXILIARY DEVICES

On breakers that ar e equipped with auxiliary
devices such as a current trip, undervoltage trip or
capacitor trip, the device should be checked for

proper electrical operation. The current trip device
should trip the breaker at 3 amperes. The under
voltagetrip device should trip the breaker when the
control voltage drops below 40 to 60% of rated volt
age, and it should pick-up at 80% d the control

voltage or less. An adjustment plate is provided on

the front of the undervoltage trip device as an aid
in obtaining the desired setting. CAUTION: Voitage
applied to the undervoltage device should be brought

up tothe pickup value within a periodof 20 seconds,

to avert dama^g the pickup coil. The capacitor

tions.

trip should be capable of tripping the breaker as

late as 25 seconds after the control voltage is re
moved. If the auxiliary devices do not perform in
accordance with these specifications, a careful
examination should be made for defective parts.
CONTROL POWER CHECK

Fbr electrical operation of the breaker, the
control power may be either an alternating or direct
current source. For AC operation, two rectifiers,

mounted elsewhere in the metal-clad unit, are used.
A tapped resistor is provided in each AC circuit

to control the DC voltage. The resistor setting
should be adjusted so that the voltage at the breaker

is 110 to 120 volts DC. Where repetitive operation
is required, the voltage should be set at 105 to
115V. DC.
This resistor should be set under
normal summer conditions as described below. To

check the resistor setting, proceed as follows:
1. Mechanism with a Control Device - Close
1. Front Bushing
2. Fork Lever

3. Locking Bolts

Fig. 9
10

4. Pin
5. Link
-6. Rod

Auxiliary Switch Linkage

the breaker by manually operating the control de
vice contacts (5) and (6) Fig. 12. Hold these con
tacts in the closed position and read the DC voltage
at the closing coil. To de-energize the circuit,
release the control device.

2. Mechanism with Cut off Switch, Fig. 9 -

Magne-blast Circuit Breakers Type AM

Close the breaker by manually operating the con
trol relay located in the metal-clad unit. Hold this
relay closed and read the DC voltage at the closing
coil terminals. Release the closing relay to de-

GEH-1804

checked at the closing coil and trip coil terminals.
The operating ranges for the closing and tripping

voltages are ^ven onthe breaker nameplate. Ordi

narily, standard ranges apply which are as follows:

energize the circuit.
DO NOT MAINTAIN VOLTAGE ON THE CLOS
ING COIL ANY LONGER THAN THE FEW SECONDS

REQUIRED TO READ THE VOLTMETER. These

coils are designed for intermittent operation and
will be damaged by prolonged current flow.
The following tabulation in included as a guide

for adjusting the resistors for the particular com
bination of ambient temperature and AC supply
voltage. Summer settings are used where ambient

temperatures are normally above freezing (32°F).

tt is necessary to use winter setting where the
ambient temperature may drop to 20°F or less at

any time. For a more detailed explanation of
Copper-<»ide Rectifiers for circuit breaker ap

plication, refer to Instruction Book GEI-11306.
Resistor Setting, Ohms

•AC Volts

(Closed
Circuit)

Summer

Winter

1/4

0
0

190-196
194-206
204-216
214-226
224-236
234-246
244-250

•

1/2

1/4
1/4

3/4
1

1-1/4
1-1/4

1/2
3/4
1

AC Volts as measured across the rectifier
and AC series resistor.

NOMINAL
VOLTAGE

CLOSING
RANGE

TRIPPING
RANGE

125V. DC

90-130V. DC

70-140V. DC

250V. DC

180-260V. DC

140-280V. DC

230V. AC

190-250V. AC

NOTE: Where repetitive operation is required
the maximum voltage should be 115 V. DC and
230 V. DC at the nominal voltages of 125 V. DC &
250 V. DC respectively.
Electrical closing or opening is accomplished

by merely energizing the closing or trip coil cir
cuit. Coirtrol switches are provided for this pur
pose on the metal-clad unit. It is also possible to
trip the breaker manually
pressing the manual
trip button (5), Fig. 1.
When all the foregoing inspection details have
been checked, the breaker may be safely placed in

service. Before the breaker Is finally r^ed into

position in the metal-clad unit, rub a small amount

of G.E. Contact Lubricant D50H28 on the silvered
portion of the breaker studs to form a thin coating
for contacting purposes.
CAUTION:

This breaker mechanism combina

tion is designed only for electrical closing when in

After the breaker has been closed and opened
slowly several times with the maintenance closing

THE BREAKER IN SERVICE, for under such condi

descrioed above, the operating voltages should be

tions, sufficient closing force and speed cannot be
applied.

device, and the mechanism adjustments checked as

use. NEVER ATTEMPT MANUAL CLOSING WITH

OPERATION
CLOSING

OPERATION

Figs. 12 and 13 show the four basic control
schemes that are used on Magne-blast breakers.

The important difference between Fig. 12 and Fig.
13 is that in the circuits shown in Fig. 12, a control
device is used for the closing operation whereas in

Fig. 13, a cutoff switch and relay arrangement is
used for the same purpose. The reason for this is

being closed only momentarily, but the closing
operation will continue until completed.
At the same time the control device contacts

(5 and 6) are latched in the closed position, ener
gizing the breaker closing coil. Refer now to Fig.

11. The closing armature (6) travels upward, rais
ing the roller (4). This motion is transmitted

through the mechajiism linkage to rotate the main

shown in Fig. 13 are designed primarily to replace

operating cranks (1), closing the breaker. During
the closing operation, the opening springs (9 and 10)

breakers of older design that have similar control
circuits. It may also be noted that all AC control
circuits are equipped with a rectifier, which is

ation. At the end of the closing stroke the prop (12)
engages the pin (11), latching the breaker closed.

because all breakers having a control circuit as

used to convert AC power to DC power on which
the closing coil operates.

Take for example the AC control circuit shown

in Fig. 12 (upper)*. Closing of the breaker is in

itiated by actuating the CLOSE control switch on
the metal-clad unit. Referring to Fig. 10, the con
trol device coil (3), is immediately energized, and

are compressed in readiness for the opening oper

The & which is trapped abovethe closing armature
(6) acts as a dashpot, absorbing the remaining
kinetic energy of the closing armature.

The plunger (9), Fig. 1, strikes the trip lever
(9), Fig. 10, to trip open the control device contacts

(5 and 6). This de-energizes the closing coil per

mitting the closing armature to return by gravity to

crank (4) closes the seal-in switch (2) which shunts
the CLOSE control switch. With this arrangement,

its original position. The seal-in switch (2) opens
but the anti-pump switch (1) will not open unless
the close control switch has been releas^. This is
to prevent pumping (reclosing) when the breaker is

the CLOSE control switch may be released after

closed on a fault.

as the control device linkage starts to move, the

GEH-i804

Mdgne-blast Circuit Breakers Type AM

1. Shunting and Anti-Pump Saitch

6. Movable Contact Assembly

2. Seai-in Switch

7. Arm

3. Operating Coil

8. Arc Quencher

4. Crank

5. Stationary Contact Assembly
Fig. 10

Fig. II

9. Trip Lever
10. Plunger Guide
Control Device

Cross Section Of HS-13 Operating Mechanism In The Open Position

Magne-bldst Circuit Breakers Type AM GEH-1804
(•J) OR (X)

U ItFbSE

(*)-

C CONTROL

7 kyice

CONTACTS

INDICATING^

0 LAHM 0

TRIP
CONTROL

=j=MITCH

PROTECTIVE i
DEVICE

LOSINO
COIL

RECTIFIER

RESISTOR

^ TRIP
COIL

(Y)FUSE

(-) OR (Y)AC CLOSE AND AC OR DC TRIP

i*)—C3FUSE

(♦)-

LAMPS

CONTROL

CLOSE
CONTROL
SWITCH

i DEVICE
''

CONTACTS

r
©
a

INDICATING
..j :

S-"

TRIP

CONTROL
SWITCH

PROTECTIVE%
DEVICE

CLOSING
COIL

thyrite

JRESISTOR
2S0VDC
ONLY

TRIP
COIL

(-)FUSE

(-)—o-

DC CLOSE AND DC TRIP

t
b

Fig. 12

NORMALLY OPEN AUXILIARY SWITCH
NORMALLY CLOSED AUXILIARY SWITCH

UTCH CHECXING SWITCH (FOR RECLOSIHG OPERATION)

X
XI
X2

CONTROL DEVICE OPERATING COIL
CONTROL DEVICE SEAL-IN CONTACTS
CONTROL DEVICE AHTI-PUMP CONTACTS

CONTROL DEVICE SHUNTING CONTACTS (ALSO ANTI-PUMP)

Typical Eienctitary ;;irin£ Oiasraiss For Type AM-2.H/H. 16-IOO/ISO-l and -150/250-1
Magne-biast Circuit breakers, bnohn In The Ce-energized Position

GEH-1804 Magne-blast Circuit Breakers Type AM
+) 0* (*)-0FUSES

(*)Ha
TRIP

CORTROL
SUITCH

PROTECTIVE
DEVICE

aOSING

rectifies

RESISTOR

(T)-a
(-) o« (D-fl—n-

FUSES
RC CLOSE MO M OR DC TRIP

(♦rO
(♦HO-

«
••

FUSES

1 irdicatinoJ

0
;X2

UHPS

TRIP
CORTROL
.SNITCH

aosE
:CONTROL
SNITCH

c
protective:
DEVICE

=Ta
VI

> ClOSIRS
COIL

TRIP
COIL

(-)-aFUSES

(-)-a-

Fig. 13

DC CLOSE MO DC TRIP

1
b
M
X

HORMRUT OPEN ROXILIMY SNITCH
NOnUUT aOSEO ruxilirry snitch
CUT-OFF SNfTCH
CLOSINO REUY COIL

XI
XI
Y

REUY CLOSINO CONTRCTS
REUY SERL-IN CONTRCTS
RUXILIRRY REUY COIL

RUXILIRRY REUY CUT-OFF CORTRCTS

RUXILIMY RORY RNTI-PIMP CORTRCH

Typical Elenentary Wiring Diagrans For Type AH>2.U/per Horizontal Barrier

19. ^ring Retainer

6. Stationary Arcing Contact
7. Box Barrier
8. Arc Chute

9. Poie Piece
10.
11.
12.
13.

Arc Runner
Blow-out Coil
Blow-out Core
Ifuffler

14. Front Bushings
15. Rear Bushings

Fig. IH

20. Lower Horizontal Barrier

21.
22.
23.
24.

Operating Bod
Stationary Primary Cantaets
Uovable Primary Contacts
Cup Bearing

25. Clevis

26. Movabie Contact Arm Assembiy
27. Movable Arcing Contact28. Booster Tube
29. Connection Bar

30. Booster Cylinder and Piston

Cross Section Of Breaker Pole Unit

GEH-1804 Magne-blast Circuit Breakers Type AM
The closing speed ofthe arcing contactsthrough
toe arcing zone should be within toe range of 10 to

18feet per second, at rated control voltage.

OPENING OPERATION
An electrical opening operation is initiated by
energizing the trip coil. This is accomplished
either by actuating the opening control switch on
the metal'clad unit or by a combination of relays
Md current devices used to detect a fault on the

load side of the breaker. By energizing the trip
mU, toe trip plunger rotates the trip latch (2),
Fig. 11, causing the operating mechanism linlmg? to

coBapse The energy stored in the opening springs

(9 and 10) is thus released, opening the breaker.
During this operation, the trip coil circuit is de-

energized,and upon completion of the opening oper

ation, the operating mechanism is returned to its

normal position, ready for closing.

As the breaker opens, the main contacts part
first, shunting the current through the arcing contects. An arc forms as toe arcing contacts part.
See Fig. 14. As toe movable arcing contact (27) is
withdrawn through toe slot in the arc runner, the
upper end of toe arc is transferred to the upper
arc runner (4). To assist the interruption at this

divergingarc runners bythe magnetic field, the arc
transfers from toe first segment of the upper arc
rimner to the second. By this action, toe second
blow-out coil is inserted into toe circuit to produce
an additional magnetic force to drive the arc on.

At toe same time, the arc is being forced into

the arc chute (8) which is composed of a series of
gradually interleaving Insulating fins. These fins,
which project alternately from the two opposite
inner surfaces of the chute, elongage toe arc into a
gradually deepening serpentine path, so that the

electrical resistance in the path ofthe arc is riqpidly
The increased resistance reduces both toe ma^increased and the heat from the arc is absorbed.

tude and the phase angle of the current, and at an

early current zero the arc path is so long, and the
gases produced by the arc so cooled that the arc

cannot re-establish itself, and interruption occurs.

Ma^al tripping follows the same procedure

«cept that instead of energizing the trip circuit,
the manual trip (5), Fig. 1, is used.

The opening speed of toe arcing contacts
through the arcing zone should be within the range
of 10 to 18 feetper second, at ratedcontrol voltage.

^ emitted from toe booster
outlet (28) and forces toe
arc onto the lower arc

runner (10). Establishment of the arc on the runners
automatically inserts the blow-out coils into the

circuit, introducing a magnetic field between the
pole pieces which tends to draw the arc away from

toe arcing contacts. The arc chute contains two

upper magnetic blow-out coils electrically con
nected in series and one lower blow-out coll, each
individually connected to a segment of the arc run
ners. As the arc is forced outward along the

TRIP FREE

OPERATION

If the trip coil circuit is energized while toe
breaker is closing, the trip plunger will force the
trip latch (2), Fig. 11, away from toe trip roller (3)
causing the mechanism linkage to collapse and the
breaker to re-open. The closing armature (6) com
pletes its closing stroke, but toe closing coil is deener^edat theend ofthe stroke, and toe armature
is returned to its original position by gravity.

MAINTENANCE
Dependable service and safer power equip
binatlon of fault duty and repetitive operation is
mentare contingent upon the unfailing performance
encountered, an Inspection if recommended sifter
of the power circuit breaker. To maintain such ser
severe fault operation. The following instruc
vice, it is recommended that a definite inspection
tions list the main points to be included in an in
and maintenance schedule be set up and followed,
spection, anda number of general recommendations.
as serious shutdowns can often be avoided by locat
ing potential sources of trouble in an early stage.
ARC CHUTES
A periodic lubrication of parts subject to wear is
ateo vitally important for the successful operation
It is not necessary to inspect the arc chutes
of the breaker.
unless there is evidence of damage or if the arc
chutesare remwedfor anyreason. When inspecting
CAUTION: Before any maintenance work is per

formed make certain that all control circuits are

de-energizedand that the breaker primary circuits

are open and effectively grounded. Also, do not
work on the breaker or mechanism while in toe

closed position unless the prop and trip latch have
been securely wired or blocked to prevent acci

dental tripping.

PERIODIC INSPECTION
The frequency of periodic inspections should
be determined by each operating company on the
basis the number ofoperations (including switchtog), the magnitude of currents interrupted, and any
unusual operations which occur from time to time.
Operating experience will soon establish a mainte

nance schedule which will give assurance of proper
breaker condition. On installations where a com16

arc chute, it should be disassembled and toe

following points noted:

1. Scale formed over the surface of the chute

must not be removed, but loose particles

collected in the chute should be blown out.

2. Cracks which have formed in the fins of the
arc chute are to be expected in ceramic
materials of this type when subjected to the
severe heat of an arc. These cracks do not

interfere with the operation of the device in
any way and should be disregarded.

3. If the chute has suffered any mechanical
injury dueto droppingor accidental strik^g,
resulting in the actual breaking off of fins,
replacementthe chute will be necessary.

Magne-blast Circuit Breakers Type AM
BREAKER CONTACTS

GEH-1804

LUBRICATION

In order to maintain reliable operation, it is
Important that all circuit breakers be properly lub

By removing the box barrier the movable and

stationary primary contacts and the movable arcing
contacts can be inspected. The stationary arcing
contacts can be inspected only after removing the
arc chute and the arc runner side barrier (11), Fig,

ricated at all times. Duringassembly at the factory,

all bearing surfaces, machined surfaces, and all

other parts of the breaker and mechanism subject

1§, as explained under REPAIR AND REPLACE
MENT. If the contacts are burned or pitted, thCT

finestgradeof lubricants a^dlable. However, even

should be made smooth with a fine file.

thefinestoils and greases havea tendencyto oxidize

to wear have been properly lubricated using the

with age, as evidenced by hardening and Hgfirni^tngr

After completing inspection of the contacts,

check the contact adjustments as specified under
INSTALLATION, ADJUSTMENTS.

in color. Elimination of the hardened lubricant is
essential for the proper operation of circuit
breakers. Also frequent operation of the breaker

MECHANISM

the bearing surfaces. A simple lubrication will

causes the lubricant to be forced out from between

often clear up minor disturbances which might be
mistaken for more serious trouble.

A careful inspection should be made to check for

loose nuts or bolts and broken retaining rings. All
cam, roller, and latch surfaces should be inspected

A definite lubrication schedule should be set

up taking into consideration the frequency of oper

for any evidence of damage or excessive wear.

ation of the breaker and local conditions. Until such

close the breaker several times to m»e certain

a schedule is worked out, the breaker should be
lubricated at each periodic inspection and also
whenever it is overhauled, in accordance with the

entire stroke. Check the mechanism adjustments as

that all circuit breakers be operated at regular

Lubricate the mechanism as outlined below, then,
using the maintenance operating device, open aM

that the mechanism operates freely throughout its

lubrication chart. Fig. 15. It is also recommend^

specified under INSTALLATION, ADJUSTMENTS.

intervals to insure the user tl^ the equipm^ is

Check all terminal connections.

operating freely.

BUSHINGS AND INSULATION

The lubrication chart is divided into two meth
ods of lubrication. The first method outlines the

The surface of the Herkolite* bushings should
be kept clean and unmarred to prevent moisture

at the time of periodic maintenance, and requires

maintenance lubricationirtiich should be perform^

no disassembly. The second method outlines a
lubrication procedure similar to that performed on

absorption. Hthe insulation surface should become

damaged, it should be sanded and cleaned, and

the breaker at the factory, but should be used only
in case of a general overhaul or disassembly for

should be refinlshed with either clear varnish

{GE-1170), clear Glyptal* (GE-1202), or brown
Glyptal* (GE-1210). Allow to dry smooth and hard.

other reasons, or if the operation of the breaker
becomes slower.

Allc^er insulation parts on the breaker should

General Electric Lubricant DS0H15 is available

be kept clean and dry. Smoke or dust collected be

only in cartons containing twelve collapsible tubes

to insure dryness.

to the carton. It is so packaged to insure cleanli
ness and to prevent oxidation.

tween inspection periods should be wiped off, and if
dampness is apparent, heaters should be installed

Part

Ground surfaces such as

cams, rollers, latches, etc.
Booster cylinder

of grease. This is a total of three poun& of grease

Lubrication At
Maintenance Period

Vipe clean and apply
D50H15

Vipe clean and apply
thin film cd DS0H15

Sleeve Bearings
(Mechanism and Breaker
linkage)

Very light application
of light machine oil
SAE-20 or -30

Alternative Lubrication

(Requires Disassembly)
Wipe clean'and apply
DSOHIS

Wipe clean and apply
thin film of DSOHIS

Remove pins and Hnitg

and clean as per clean
ing instructimis below.

Apply DSOHIS Liberally
Removable Seal and

Open Type Ball,
Roller and Needle

Light application of light
machine oil SAE -20 or
-30

and Primary Discon

Wipe clean and apply
D50H28

♦

Reg. Trade-Mark of General Electric Company

Wipe clean and apply
D50H28

nect Studs

Fig. 15

instructions below and

repack with DSOHIS

Bearings
Silver Plated Contacts

Clean as per cleaning

Lubrication Chart
17

GEH-1804

Magne-blast Circuit Breakers Type AM

METHOD OF CLEANING BEARINGS

Wherever cleaning is required, as indicated in
the lubrication chart, the following procedures are
recommended:
Sleeve Bearings

particular types of distress that might be encount
ered, together with suggestions for remedying the
trouble;
FAILURE TO TRIP

1. Mechanism binding or sticking caused by
lack of lubrication.

The pins should be removed and all old oxidized

REMEDY: Lubricate complete mechanism.

solvent or similar cleaner. DO NOT USE CARBON-

2. Mechanism binding or sticking caused by

grease removed 1^ immersion in clean petroleum

TETRACHLORIDE. Wipe the bearing clean. Apply

a small amount of G. E. Lubricant D50H15 to the

entire surface of the bearing and pin just before
reassembling.

Removable Seal and Open Type Ball. Roller and
Needle Bearings

The bearings should be first removed from the

mechanism and disassembled Iq? the removal of the
seals or inner race in the case of nee^e bearings.

They should then be placed in a container of clean
petroleum solvent or similar cleaner. DO NOT USE

CARBON"TETRACHLORIDE. If the grease in the
bearings has become badly oxidized it may be
necessai7 to use alcohol (type used for thinning
shelmc) to remove it. Ordinarily, by agitating the
teartogs in the cleaning solution, and using a stiff
brush to remove the solid particles, the bearings

can be satisfactorily clean^. Do not handle the

beutogs with bare hands as deposits from the sl^
onto ihe bearings are inducive to corrosion. If the

bearing are touched, the contamination can be removed by vmshlng in alcohol. After the bearings
haVe been thoroughly cleaned, spin them in clean
new light machine oil until the cleaner or solvent
IS entirely removed. Allow this oil to drain off and

then repack them immediately with G. E. Lubricant

D50H15 being sure all metal parts are greased.

The removable seals should then be replaced.

CAUTION: If it becomes necessary t o clean the

being out of adjustment.

REh^DY: Check all mechanism adjust

ments, latches, stops, auxiliary devices,
etc„ in accordance with INSTALLATION,

ADJUSTMENTS. Examine latch and roller
surfaces for corrosion.

3. Damaged trip coil.
REMEDY: Replace damaged coll.
4. Blown fuse in trip circuit.
REMEDY: Replace blown fuse after deter
mining cause of failure.

5. Faulty connections in trip circuit.
REMEDY: Repair broken or loose wires

and see that all binding screws are tight.

6. Damaged or dirty contacts in trip circuit.
REMEDY: Recondition or replace contacts.
FAILURE TO CLOSE OR LATCH CLOSED

1. Mechanism binding or sticking caused by
lack of lubrication.

REMEDY: Lubricate complete mechanism.

2. Mechanism binding or sticking caused by
being out of adjustment.

REMEDY: Check all mechanism adjust
ments, latches, stops, auxiliary devices,
etc., in accordance with INSTALLATION,
ADJUSTMENTS. Examine latch and roller

surfaces for corrosion.

bearings in alcohol (shellac thinner) be sure the

3. Control device sticking or not operating

tearings to remain in the alcohol more than a few

REMEDY: Checkand adjust control device,

alcohol is perfectly clean, and do not allow the

Iwurs. U it is desirable to leave the bearings in

the alcohol for a longer time, an inhibited alcohol

properly.
or replace.

such as is used for anti"freeze should he used.
Even then the bearings should be removed from the
alcohol within twenty-four hours. Esso Anti-

4. Damaged or dirty contacts in control cir

ofthe alcohol must be exercised by wearing rubber
gloves and by using the alcohol in a well ventilated

5. Damaged control device coil.

Freeze and Du Pont Zerone are satisfactory for
thte purpose. Precautions against the toxic euects

cuit, including control device.

REMEDY: Recondition or replace contacts.
REMEDY: Replace damaged coil.

room; excessive exposure to the fumes is some

times impleasant to personnel. Washing the bear-

ings in light oil and draining should follow imme^ately, then apply the lubricant.

6. Damaged closing coil.
REMEDY: Replace damaged coil.
7. Defective cut-off switch or latch-checking

TROUBLE SHOOTING
Failure of a breaker to operate properly will

generally fall within three general classes: Failure

to trip, failure to close or latch closed, and over
heating. The following is a brief outline showing
18

€

switch.

REMEDY: Replace defective switch.

8. Blown fuse in closing circuit.
REMEDY: Replace blown fuse after deter
mining cause of failure.

Hagoe-blaat Circuit Breakers Type AM GEH-1804
9. Faulty connections in closing circuit.
REMEDY:

Repair broken or loose wires

and see that all binding screws are tight.

10. Insufficient control voltage caused by ex
cessive drop in leads.

REMEDY: Install larger wires and improve
electrical contact at connections.

Fll

11. Insufficient control voltage caused by poOr
regulation (AC control).
REMEDY: Install larger control transfor
mer. Check rectifier to be sure it is de

livering adequate DC supply.
OVERHEATING

1. Poor condition of contacts due to lack of

attention after severe duty or too frequent
operation.

REMEDY: Recondition or replace burned
andpitted contacts. (Contacts should be re

1.
2.
3.
4.

conditioned very carefully and only when
absolutely necessary.)

2. Contacts not properly aligned or adjusted.

5. Lover Horizontal Barrier

REMEDY: Check all adjustments in ac
cordance with INSTAL'^ATIW, ADJUST

6. Mounting Bolts

7. Arc Qiute Assenbly
8. Mounting Nuts

MENTS.

3. Breaker kept closed or open for too long a
period.

Rear Bushings
Front Bushings
Mounting Bolts
Upper Horizontai Barrier

Fl9< 16

necessary.

4. Overloading.
REMEDY: Replace breaker with one of

Rear View Of Breaker With
Box Barrier Reaioved

REMEDY: Operate breaker more often to
wipe contacts clean. Replace contacts if

and remove the box barrier (7), Fig. 14. Remove
the mounting bolts (6), Fig. 16, and nuts (8), and the
arc chute (7) will be released.

adequate rating for present or future load,
or re-arrange circuits so as to remove ex
cess load.

5. Primary connections of inadequate capacity.
REMEDY:

proceed as follows:

Increase size or number of con

ductors or remove excess current.
6. Loose connections or terminal connectors
REMEDY: Tighten.

7. Ambient temperature too high.

REMEDY: Relocate in a cooler place, or

arrange some means of cooling.

REPAIR

To disassemble the arc chute after it has been

removed from the breaker, refer to Fig. 17 and

AND REPLACEMENT

The following information covers in detail the
proper method of removing various parts of the

breaker in order to make any necessary repairs.
This section includes only those repairs that can
be made at the installation on parts of the breaker

that are most subject to damage or wear.

1. Remove the assembly hardware (1, 2, 3, 6,
and 8) and lift off the arc chute upper half
(4). The arc chute side (9) can now be re
moved.

2. Remove the side piece (7) and the insulation
spacer under the side piece. The arc run

ner (10) and blow-out coil (13) may now be
removed.

3. Reassemble in the reverse order. Before

tightening the assembly hardware, arrange
the two halves of the arc chute so that the

fins are equally spaced.
CONTACTS

IMPORTANT: UPON COMPLETION OF ANY RE

PAIR WORK, ALL BREAKER AND MECHANISM
ADJUSTMENTS MUST BE CHECKED. Refer to the
section on INSTALLATION, paying particular atten

tion to ADJUSTMENTS and FINAL INSPECTION.
ARC CHUTES AND LOWER ARC RUNNERS

To remove an arc chute, first open the breaker

Open the breaker and remove the box barrier

and arc chutes as already described. Then proceed
as follows;

1. Remove the connection bar (9), Fig. 18.
2. Remove the cup bearing (3).

GEH-1804 Magne-blast Circuit Breakers Type AM

1.
2.
3.
4.

Assenbly Bolts
Assembly Bolt
Assembly Bolt
Are Chute Upper Half

9. Are Chute Side
10. Arc Risiner

11. Mounting Stud
12. Blov-out Core

5. Arc Chute Lover Half

13. Blow-out Coil

6. Assembly Bolts

14. Insulation Spacer

7. Glass Bended kUca Side Piece

15. Glass Bonded Uica

8. Assembly Bolts

Fig. 17

Side Piece

Arc Chute Disassembly

3. Remove the assembly bolts (6) and (8), and
the movable primary contacts (5) and mov
able arcing contact (7) will be removable.

4. To remove the stationary primary contacts
(2), compress and

remove the contact

spring (1) and raise the contact finger and
slide it out. When assembling, apply a
thin coating of D50H28 grease to the hinge
portion of the contacts.

5. To remove the stationary arcing contact
(17), Fig. 19, first remove the side piece
(11). Remove the screw holding the con
tact braid (14), then turn the contact finger
assembly 90 degrees and pull it out from
the side.

6. Reassemble in the reverse order, then
check all contact adjustments as described

under INSTALLATION, ADJUSTMENTS.

BUSHINGS

1. Contact Springs
2. Stationery Primary Contacts
3. Qjp Bearing
4. Contact Arm

5. Movable Primary Contacts
6. Assembly Bolts

IMPORTANT;

DO N OT REMOVE A L L SDC

BUSHINGS AT ONCE. Thebushingshavebeencare"
fullyaligned withthe breaker frame, during assem
bly at the factory, and it is important that this

alignment be maintained to facilitate installation of
the breaker in the metal-clad unit. It is therefore

6. Assembly Bolts

recommended that the bushings be removed and re
assembled one-at"a"time. Also, before removing

9. Connection Bar

any one bushing, measure the distance from that

7. Movable Arcing Contact

^i9- 16

Removal Of Contacts

particular bushing to adjacent bushings in both
directions, so that it may be reinstalled in the same
location.

Magne-blast Circuit Breakers Type AM GEH-1804

!• Sear Bushing

7. Spring Retainer

i. t^er Insulation
3. Cbil Support
4. A seebly Bolts

8. Asseobly Bolts
9. Contact Springs
10. Cbil Protector

5. Asseirbly Bolts

16.

11. Glass Bonded Uica Side Piece

6. Aaaes^ly Bolt

12. Bloe-out Coil

17. Stationary Arcing Cbntact
18. Stationary Primary Contacts

F«9' 19

It is also possible to remove and reassemble

bolts. This must be done before the arc chutes are
reinstalled.

Rear Bushing and Arc Runner Assembly

1. Open the breaker and remove the box bar

rier and arc chutes as already describ^,

2. Removethe upper and lower horizontal bar
riers (4 and 5), Fig. 16.

3. Remove the four bolts (3) at the mounting
flange of the rear bushing being removed,
and lower the bushing and arc runner as
sembly.

4. For further disassembly, refer to Fig. 19.
Removethe bolts (8) and the spring retainer
(7). Remove the bolts (4, 5, and 6) to re
move the bushing (1). The stationary pri
mary contacts (10) may also be removed if
necessary.

5. Remove the side pieces (2 and 11) and the
insulation (3), making it possibletoremove

the arc runner segments (13 and 16) and
8, Reassemble in the reverse order.

14. Cbntact Braid
15. Blo*-out Coil
Arc Runner

Disassembly Of Upper Arc Runner Unit

three bushings at one time. If this is preferred,
alignment of the bushings may be accomplished by
placingthe breaker in a de-energized spare metalclad unit before tightening the bushing mounting

blow-out coils (12 and 15).

13. Arc Runner

Front Bushings

1. Open the breaker and remove the box bar

rier and arc chutes as already described,
2. Reroovetheupper andlower horizontal bar
riers (4 and 5) Fig. 16.

3. Remove the connection bar (9) and cup
bearing (3) Fig. 18.

4. Removethefour boltsatthe mounting flange

of the front bushing being remov^ and
lower the bushing.

5. When reassembling, first mount the bush
ing and assemble the cup bearing (3) and
contact arm (4), Fig. 18. The contact surfaces at the hinge point of the contact
blade and •bushing should have a thin
coating of D50H28 grease.

6. Reassemble and check all contact adjust
ments as outlined under INSTALLATION
ADJUSTMENTS.
CLOSING COIL

The closing coil is contained within the solenoid

pot (3), Fig. 20. To remove the closing coil pro
ceed as follows.
1. Open the breaker.

GEH-1804 Magne-bUst CircuitBreakers Type AM

1. Qosing Coil Lead Wires
2. Solenoid Pot
3.

Bottom Plate

4. Guide Bolts

5. Closing Armature
6. Stop Nuts

Fig. 20

Closing Solenoid Assembly

2. Remove the two stop nuts (6), allowing the

1. Pivot Pin
2. Qevis

3. Trip Coil

8. Closing Coil Leads
9. Pivot Pin

10. Trip Shaft

4. Trip Coil Support

11.

armature(5) tobe loweredfrom the mecha

5. Mounting Bolt

12. Latch Qieeking

nism.

6. Opening Spring Unit

3. Disconnect the two closing coll lead wires

4. Dismantle the terminal board, which is

7. Trip CoiJ Leads

Fig. 21

Bolts

Switch

13. Trip Lever

Latch Checking Switch and Potential Trip

mounted on the opposite side of the solenoid
pot (2),

5. Loosen thefour nuts under the bottom plate
(3) that hold the pole piece to the mecha
nism. This permits the solenoid pot (2) to
be removed by sliding it forward.
6. Remove the four nuts, to lower the bottom
plate (3) and closing coil.

7. Reassemble in the reverse order, then
check the mechanism adjustments as ex

trip coil support (4).

4. Remove the trip coil (3).

5. After reassembling (In the reverse order)
check the primary contact gap adjustment
as explained under INSTALLATION, AD
JUSTMENTS.

LATCH CHECKING SWITCH

plained under INSTALLATION, ADJUST

MENTS.
TRIP COIL

To replace the potential trip coll <3), Fig. 21,
proceed as follows:

1. Open the breaker and remove the opening
sprmg pivot pin (1) and pull the opening
spring unit (6) forward out of the way.
2. Disconnect the two trip coll lead wires (7).

3. Remove the two mounting bolts (5) and the

To remove the latch checking switch (12), Fig.

21, remove the two mounting bolts (11) and dis
connect the lead wires. When remounting the

switch, adjust the latch checking switch wipe as
explained under INSTALLATION, ADJUSTMENTS.
CUT-OFF SWITCH

To remove the cut-off switch (1), Fig. 7, re
move the two mounting bolts and disconnect the

lead wires. When reassembling, check the cut-off
switch adjustment as explained under INSTALLA
TION, ADJUSTMENTS.

Magne-blast Circuit Breakers Type AM

GEH-1804

RENEWAL PARTS
RECOMMENDATIONS

It Is recommended that sufficient renewal parts
be carried In stock to enable the prompt replace
ment of any worn, broken, or damaged parts. A
stockof such parts minimizes service interruptions
caused by breakdowns, and saves time and expense.

A
m

ORDERING INSTRUCTIONS
When ordering renewal parts, address the
nearest General Electric Sales Office, specifying

the quantity reqtilred, and describing each part by

the catalog number obtained from the Renewal

When continuousoperation is a primary considera

Parts Bulletin.

aniount depending upon the severity of the service
and the time required to secure replacements. **

of the breaker be furnished by supplying the Infor
mation found onthe breaker nameplale and, If pos

tion, more renewal parts should be carried, the

It is also suggested that complete identification

A complete list of renewal parts Is contained
in the Renewal Parts Bulletin GEF-3873. Those

sible, the number of the requisition on which the
breaker was originally furnished.

damage or breakage due to possible abnormal
conditions, are marked as recommended renewal

Renewal parts which are furnished may not be
Identical to the original parts, since improvements
^e made from time to time. The parts which are
furnished, however, will be interchangeable.

parts subject to wear in ordinary operation, and to
parts.

GEH-2000

[NSTRUCTIONS

SUPERSEOSS

AND

RENEWAL PARTS
EDWARD L WALENGA

515 45tJi ST,

MUNSTER, IN 46321
(219) 922-4211
(708) 709-0687

GB Supply

FAX: 219-9224225

MAGNE-BLAST
CIRCUIT BREAKERS
Types
AM-4.16-150-3
AM-4.16-150A-3
AM- 4.16-250-3
AM- 4.16-250A-3
With MS-13 Mechanism
CONTENTS
INTRODUCTION

RECEnTNG, HANDLING
AND STORAGE
DESCRIPTION

INSTALLATION
OPERATION
GENERAL MAINTENANCE

RENEWAL PARTS

MEDIUM VOLTAGE SWITCHGEAR DEPARTMENT

GENERAL

ELECTRIC

PHILADELPHIA,

PA.

6EH-2000E

GEH-zO-10 Mapie-Blast Circui®i-eaker Type AM-4.16

I -•-V .

"52'!?

1. Secondary Coupler
2. Auziliery Seitch
3.

Position Indicstor

4. Opening Spring Unit
5. Operstlon Counter

6. UsnuaX Trip
7.

Control E^vice

8. Control Device Plunger Guide
9. Closing Solenoid

10. Plunger Interlock (Optional)

•^1

•iJli
•-..rr

^i9i i

MS-13 Operating HechsAi

"•'Ki

fiVtl.

IS k
•m

1. Closing Araature

2. Uaintensnce Operating Device

Fig. 2

3.
*.

Handle
Release Valve

Method of Mounting Mainteiance Operating Device

MAGNE-BLAST CIRCUIT BREAKER

TYPE AM-4.16 WITH IViS-13 MECHAHISM
INTRODUCTION
The Magne-blast Circuit Breaker is the
removable interrupting element for use in

vertical-iUt metal-clad switchgear, toprovide reliable controland protectionofpower
systems. Among the many advantages of
metal-clad switchgear are added protection
m equipment and personnel, compactness,
simplified installation and reduced mainten^ce. In keeping with these features the
Magne-blast breakers are designed for interchangeability and manueverabiiity, together with reliability and low maintenance
requirements.

ates on Magne-blast
the principleCircuitBreakeroperthat an arc can be

interrupted in air by sufficienUy elongating given on the namepiate. Since this book
bv meane"nf *strong
f
accomplished
magnetic
field that is written to cover several ratings of
leng^ens Uie arc and forces it into in breakers that are of the same general
timate contact with cool dielectric mater- design, ail instructions will be of a generai character and all illustrations will
be typical, unless otherwise specified.
Magne-blast Breaker is

available in a number of current and
PI'OPER installation aND MAIN
voltage ratings.
Refer to the breaker
^mepiate for the complete rating inform- TENANCE ARE NECESSARY TO INSURF
ation of any particular breaker. The short
circuit conditions to be imposed on the

breaker must not exceed its rating, nor

at
voltages or currents greater operate
than those

SratlSn.

""^intainin? satisfactory

RECEIVING, HANDLING AND STORAGE
RECEIVING AND HANDLING

withme'hr^if'^'

and
inspected
^d packed by workmencarefully
experienced
in the

associated

«Sat"n.
SI
2. The breaker should be stored in a
"o parts have
from corrosive

i"®
packing
of receipt
electrical
equipment. Immediately
upon
of Seenofeaookedl''
fte circuit breaker, an examination should
^be f,1,
/"tnes;
particular
care should
taken to
protect
the equipment
from
STORAGE
=f»
sustained
in tranmoisture and cement dust, as this cominjury or *-

moved the same amount After making an

1. operating
2. Renting £od Pin
3. AdjufCing kut

adjustment, close and open the breaker

4. Oicdc hut

Both nuU should be

Md recheck the plunger clearance. Repeat
tne AdjUBtmdnt if necessary.

5. Statienary Prinary intact*
6. Uavable Primary CanCacts
7. Contact Arw
8. yoke

g. 4 Adjuatabla Coupling for Making prisary Contact Wipe Adjuetoent

t :oTr-%^iir

•• Wain Oper. Shaft
!.

Wain Crank

I. Trip Shaft
'• Trip Latch

. Trip Latch Stop
. Trip Eoiler
• Poxition Indicator
.

Clevix

. Adjustibie Stud

. Cloaing Pin

. Opening Spring Houaing
. ajening Spring. Inner

< Opening Spring, Outer
. Cioxing blier
Prop

Closing Coil

Qosing Plunger
Piston king
Set Screw
Shitts

Cloaing Arssture
Stop >futs
Arasture Guide ^Its
Stop Ifuts
Qieck Hut

Adjusting Nut

22
23
-24

Fig. B Cross Section of HS-13 HacAanI

GEH-2000 Mapie-BIast Circuit Breaker Type AM-4.16
• -1 1^^

)
1. B>ck Auxilisry Switch
2. Uounting Screw

3. Top Auriliwry Switch

:*r P J

4. Plunger
5. toerwting Arm
6. Trip Lever
T. Plunger Guide

Ir®
1. Interlock Sheft

2. Letch Check Switch Are
3. Letch Oiecking Switch
Fig. 7

4. Trip Shaft

Cofltroi Device

5. Interlock Switch Arm
6.

Interlock Switch

position, depress the arm of the cut-off

Interlock Switch and Latch
Checking Switch

switch (1). There .shouJd be 1/32" to 1/16" Plunger Interlock
Clearance between the depressed roller of (AM-4.16-I50-3 and 250-3)
<3). if
Washers
(4) should be added or removed
neces

Refer to Fig. 9. With the breaker in
the open position, the vertical distance "A"

sary to correct adjustment.

mXEHLOCK SWITCH WIPE

from the top of the interlock bolt (2) to the
bottom of the elevating bar (13) should be

AUXILIARY DEVICES

15-19/32" 1 1/16".

To change this ad

-u
••'"S to Fig.
6, routetothe
interlock
shajl
(1) manxially
clockwise
release
theek

Latch Checking Switch Wine

justment add or remove washers (3).

which the conucts make can be determined
wim a circuit continuity tester such as aiI

u
6, route the trip
Shalt ;4) manually clockwise to release

(Furnished Special on AM-4.I6-150A-3 and

Interlock switch arm (5).

The point at

Auxiliary Switch Linkage

light inaicator or bell set. To obUin ad-. the latch checking switch arm (2). The
justment on the interlock- switch (6). bend1 point at which the cbnucts make can be
the Interlock switch armlS). The roller• determined with a circuit continuity tester

250A-3)

and crank on the interlock switch (6) shouloj such
a light inaicator or bell set To
have 1/32 to 1/16" overtravel after final[ obtain adjustment on the latch checking
adjustment.
switch (3), bend the latch checking switch
arm (2). The roller and crank on the latch
CONTROL DEVICE ADJUSTMENT
checking switch (3) should have 1/32" to
1/16 overtravel after final adjustment.
Referring to Fig. 7, measure theoverUavel of the two aujclllary .-witch plungers. Impact Trip, Current Trip, Capacitor Trip.
Manually operate the control device bv
—
pressing the operitingarm (5)thefull extent and Undervoftage Trip Devices
®
in .h ,
this position "'rfurther
depress thedevice
plunger
necessary settings
14) on the top auxiliary switch (3). The that are to be checkea when these devices
furnished. The amount of wipe between
arm
the Uip roller (16) ana the trip latch (15)
should be 1/32 or greater. operating
To Increase
the overtravel, loosen the screws (2) and should be 3/32" CO 5/32". This can be
move the switch toward the rear of the nn^7t>, li"
number of shims
"^'Shten the screws and

recheck the adjustment.

a4)

BEFORE

altered by releasing the check nut and

THAT ALL control POWER CERTAIN
TO THf
DISCONNECTED

Manual operation of the controi

DEVICE WITH CONTROL POWER CON-

rnFt
TWN

move the fork level in the proper direction.

Tighten the lock bolts.

FINAL INSPECTION AND TEST

1. For ease in reviewing theadjustments,
the following are recapitulated:

a. Primary conuct wipe:

5/16" +

0 - 1/16".

In order to trip properly, the clearance

between the trip bolt (11) and the trip plate

Manually operating

center line of the Iront bushings (1) to the

center of the slot In the fork lever (2) should

be 12-9/32" as shown. To change this
setting, loosen the locking bolts (3) and

which the trip plate

In a similar manner, check the over-

travel on the back auxiliary switch (1).

Refer to Fig. 10. With the breaker in
the open position, the dlsunce from the

le"lt ar'mTl).''''
When an undervoluge device Is fur
nished check the clearance between the

trip hammer (19) ana the trip plate (14)

ENERGIZE THE CLOSING with the undervolUge coil energized. This '
should be 1/32" to 1/16" ani
produce a CLOSING OPERa- clearance
CM be altered by removing the connecting
"'e adjusting
assembly (20). ana turning
the clevisrod
at
uiAi end.

(5)irslrat'°thr'Withflct®oryL\%Tr'
adjustment.
the breaker in eSie\trr„'
opSnS

After checking ail the mechanical ad-

)ustments as outlined above, operate the
devices manually to make ceruin that thev
trip ana reset properly.

1. Cut-of/ Switch
2. Switch Roller

3. Adjusting Soft

Washers

Lever Am

Cut-off Switch Aajustfflents

Magne-Blast Circuit Breaker Type AM-4.16 GEH-2000

1. Front Oisconneet Stud

2. Plungor Interlock Bolt
3. foohera

4. Connecting Bod
5. Beiet Plate
6. Beaet Boiler

7. Main Operating Shaft
8. Beaet Arm

9. Trip Plate

10. Spring
11. Trip Bolt
12. acvii

13. Elevating Bar
14. lopaet Trip Plate
15. Trip Latch
16. Trip Roller
17. Trip Arnature

18. Trip Lever

19. Undervoltage Trip Haamer
20. Adjuating Rod
21. Manual Trip Button
22. Trip Setting Plate
23. Uidervoltage Device

Fig. 9 Adju^ents On Current Trip Device and Undervoltage Trip Device,
ShOMi With The Breaker In The Closed Position

See that all bearing surfaces of the
mechanism have been lubricated. Refer
to the section on LUBRICATION.

Operate the breaker slowly with the
maintenance closing device and note

that there Is no excessive binaing or
friction and that the breaker can be

le Front Bushing

closed positions.

3. Locking Bolts

moved to the fully opened and fully

2. Fork Lever
4. Pin

5. Link

6. Rod

See that any place where the surface

of the paint has been damaged during
installation is repainted Immediately.

HI-POTENTUL TEST

Fig. 10

If the breaker had been stored for a
long period of Ume, It Is recommended
that the Insulation be checked before the
breaker Is placed In service. A standard

Auxiliary Switch Linkage

60 cycle high potential test at 14,000 volts

b. Arcing contact wipe: 5/16" or
greater {gap at primary contacts).

k. Impact
i

3-13/16 ♦

trip roller wipe: 1/8"

1/32".

RMS will normaUy Indicate whether the
breaker Is satisfactory for service. With

the breaker contacte In the fully opened

1. Impact trip bolt clearance:
-

d. Trip Utch wipe; 3/16" to 1/4" with
trip latch resting against stop pin.
e. Prop clearance:

3/64"

1/64".

position, apply the high potential to each

terminal of the breaker Individually for

one minute with all other terminals and

m. Undervoltage trip hammer clear
ance: 3/64" + 1/64".

the breaker frame grounded.

potent^

tests

are

After hirt

made on organic

Insulating materials, these materials should

be Inspected for visible leakage current

1/16" ± 1/32".

breakers which have l)een removed from

g. Interlock switch wipe: 1/16" mln.

paths, and necessary action must be taken
Insulation that may have t>een

1. Closing plunger clearance:

1/16"

affected by moisture absorpUon. The high
^tentlal test Is also recommended for

to 3/1 e*'.

Check all nuts, washers, bolts, cotter

h. Control device switch overtravel:

pins, and terminal connections for

1/32" mln.

1. Cut-off switch overtravel:

service and stored over an extended period

of time under unfavorable atmospheric
conditions.

tightness.

1/32"

max.

r'^

AUXILIARY DEVICES
3_

Inspect all wiring to make sure that

no damage has resulted during In

). Latch checking switch wipe: 1/16"

stallation, and test for possible grounds

mln*

or short circuits.

On breakers that are equipped with

auMllary devices such as a current trip,

undervoltage trip or capacitor trip, the
device should be checked for proper

6eH-2000

Magne-Blast Circuit Breaker Type AM-4.16

electrical operation. The current trip de
vice should trip the breaker at 3 amperes.
The undervoltage trip device should trip
the breaker when the controi voltage drops

below 30 to 60% o( rated voltage, and It
should pick up at 80% o( the control volt
age or less. An adjustment plate is pro
vided on the front of the undervoltage trip

device as an ail In obtaining the desired
setting.

NOTE:

When checking the pick-up value

of the undervoltage device, apply a voltage
equal to 30% of normal control voltage to
the undervoltage device coll. The device
should pick up at this value. Do not Increase
the voltage gradually on this coll as it will

overheat the coll, producingafalse reading,
and may damage the coil if excessiveoverheating occurs.
The capacitor trip should be capable of
tripping the breaker as Late as 26 seconds
after the control voltage is removed. If

the auxiliary devices do not perform in
accordance

with

these

specifications, a

careful examination should be

made

for

defective parts.
CONTROL POWER CHECK
After

the

breaker

has

been

closed

and opened slowly several times with the
maintenance closing device, and the mech
anism adjustments checked as described

above,

the operating voltages should be

checked at the closing coil and trip coil
termliuls. For electrical operation of the
breaker, the control power may be either
an alternating or direct current source.

The operating ranges for the closing and
tripping voltages are given on the breaker

1. Shunting and Anti-Puop Svxt^

6. Uovable Contact AaSMbiy

S«ai-in Switch

Operating G>il

7.
S.

Ara
Arc Q*iute

Crank

Trip Uever

nameplate.
Ordinarily, standard ranges
apply which are as follows:
NOMINAL
VOLTAGE

CLOSING
RANGE

TRIPPING
RANGE

125v d-c

90-130V d-c

250v d-c

1S0-26OV d-c
190-250V a-c

70-140V d-c
140-280V d-c
190-250V a-c

230v a-c

to. Plunger Guide

5. StationarV Contact Aasevbly
Fig*

Control Device

r—
o

^1',

NOTE: When repetitive operation Is re-

qutred from a direct current source, the

closed circuit voltage at the closing coil
should not exceed 115v d-c and 23&v d-c

at the nominal voltages of 12Sv d-c and
250V d-c, respectively.

To check the d-c voltage at the closing
coll terminals, proceed as follows:
1.

Mechanism

with

control

device.

Fig. 11. Close the breaker by manually
operating the control device. Hold the
contacts In the closed position and read
the

d-c

voltage

terminals.

the

closing coil

To de-energize Uie circuit,

release the control device.

2. Mechanism with cut-off switch. Fig. 8.
Close the breaker by manually operating
the control relay located In the metalclad unit.
Hold the relay closed and
read the d-c voltage at the closing coil
terminals. Release the closing relay to
de-energize the circuit.
If

the closed circuit voltage at the

terminals of the closing coil does not fall
in the specified range, proceed as follows:
1. A-c control power source using copper
oxide rectifiers.

Decrease the series

Fig. 12

8. Spring Betainer
9. Opening Spring. Inner

Main Crank

2.
3.
4.
5.
6«

Trip Latch
Trip SoiXer
Closing Bsiier
Piston Sing
Closing Arasture

11. Qosing Pin

Areature Guide Bolts

14. Closing Plunger Rod

10- Opening Spring, Outer
17.

Prop

13. Closing Coil

Crass Section of HS-i3 Operating Hechanian In tAe Oeen position

Magne-Blast Circuit Breaker Type AM-4.18
resistance to increase the d-c voltage,

flow.

or increase the series resistance to

decrease the d-c voltage.
voltage at the closing coil.

Recheck

R2CTIPIEH REPEREKCE CHART
Closing Coll

Dwg Ho.

Rectifier Resistor Setting

HDpS.

uennanlua

oiiicon

Resiscor

Taps

2. D-c control power source. Check volt
age at the source of power and line

drop between the

63755210-6

58.0

power source and

1.50 -n_

1.25

breaker.

62.0

1 '

95.0

' I

FOR A-C OPERATION

1. When copper-oxide rectifiers are used
they are mounted in the metal-clad unit.

63755210-2

0.75

bridge)

115.0

A tapped 1,-1/2 ohms resistor is pro

I-*-

1 '

vided in each rectifier circuit to control

the d-c voltage. The resistor setting
should be adjusted so that the closed
circuit voltage at the breaker closing

63755220-2

iSo.o

^ M

coil terminals Is 110 to 120 volts d-c.

I '

volts d-c.

190-196
194-206
204-216
214-226
224-236
234-246

244-250

Resistor Setting For
Each Resistor
Summer

Winter

1/4

0
0

1/2
1/2

1/4
1/4
1/2

3/4
1

1-1/4
1-1/4

3/4
1

*A-c Volts as measured across the rectiller and a-c series resistor.

The preceding tabulation is included as
a guide for adjusting the resistors for
the particular combination of ambient

temperature anda-c supply voltage. Sum

mer settings are used where ambient

temperatures are normally above freez

ing (32" F). It is necessary to use winter
settings where the ambient temperature
may drop to 20® F or less at any time.
For a more detailed explanation of
copper-oxide

5
-le-l

the voltage should be set at 105 to 11a

(Closed Circuit)

0.625

Where repetitive operation is required,

•A-c Volts

GEH-2000

rectifiers

for

circuit

breaker application, refer to instruction

book GEI-11306.

2. When a germanium (color - black, flanged base) - or a silicon (color-blue,
hex base) - rectifier bridge assembly

circuit voltage at the closing coil of each
breaker must fall within the specified limits.

unit. These rectifiers are of the button-

Electrical closing or opening is ac
complished by merely energizing the closing

Is used. It is mounted in the metal-ciad

type and are hermetically sealed units.
They

have

been

tested

and the

associated resistor properly set at the
the factory. Unlike copper-oxide recti
fiers the output of the germanium or

silicon unit is affected very little by

ambient temperature changes and it
should not be necessary to disturb the
factory setting.
DO NOT MAINTAIN VOLTAGE ON THE

CLOSING COIL ANY LONGER THAN THE
TIME REQUIRED TO
CLOSE THE

BREAKER.

or trip coll circuit Control switches are
provided for this purpose on the metal-clad

tmit It is also possible to trip the breaker
rnamially by pressing the manual trip button
(6), Fig. 1.

When all the foregoing inspection de
tails have been check^, ue breaker may

be safely placed in service.

Before the

breaker is finally raised into position in

the metal-clad unit, mb a small amount of

G. E. Contact Lubricant DS0H28 on the
silvered portion of the breaker studs to

(20 Cycles max. at normal

form a thin coating forcontactingpurposes.

intermittent operation and may be damaged

bination is designed only for electrical

voltage.) Both the coils and the germanium
and silicon rectifiers are designed for
by prolonged current flow.

When two or more breakers, operating
from the same control power source, are
required to close simultaneously, the closed

NOTE; This breaker mechanism com

closing when in use. NEVER ATTEMPT
MANUAL CLOSING WITH THE BREAKER

IN SERVICE, for under such conditions,

sufficient closing force and speed cannot
be applied.

OPERATION
CLOSING OPERATION

The closing operation of the breaker

is primarily controlled by the control
device, Fig. 11, mounted on the operating
mechanism. The closing sequence is In

itiated from a control switch mounted on
the door of the metal-clad unit or at a re-

mote operating station. Operation of the

eloslu control switch energizes the pick-up

coll at the control device. As the control
device closes, seal-in contacts shunt the

closing control switch to allow the opening
of the closing control switch contacts without

affecting the overall closing operation. This
type of arrangement assures complete clos

ing of the breaker with only momentary

contact of the closing control switch.

Operation of the control device ener

gizes the breaker closing coil byclosing the
main control device contacts (5 and 6), Fig.

11. Once the con^ol device contacts are
picked up, they are electrically held in the

_ cioaed position until the breaker closing
i(p^p)eration is completed. Energizing the

breaker closing coil raises the armature
is transmitted through the mechanism link

switch is held in the closed position through
out and after the breaker closing operation,
the control device linkage will remain picked
up and be unable to reset to prepare for

the breaker contacts.

another breaker closing operation. This ar
rangement insures that "pumping" of the

(6), Fig. 12 which in turn lifts the closing

roller (4) through plunger (14). This motion

age and rotates the main crank (1), closing
As the armature

reaches the end of its travel, the prop (12)
rotates beneath the pin (11) latching the

breaker in the closedposition. During the
closing operation, the opening springs (9

and 10) are compressed in readiness for an
<9ening operation. Air trapped above the
armature acts as a daahpot to absorb the
energy of the mechanism as it approaches
the end of its stroke.

When the solenoid armature is near the

end of its stroke the control device plunger
(5), Fig. 23, mechanically trips the main

control device contacts, de-energizing the
closing coU and allowing the armature to
return by gravity to its original position.
The control device plunger also mechani

cally trips the seal-in switch, de-energizing
the control device coil if the closing control
switch is not closed. If the closing control

breaker will not occur during a trip-free
operation.

The

operating sequence

for

those

breakers designed for MI-6 metal-clad
equipment is

similar to that described

above except thata relay mounted elsewhere

in the metal-clad unit replaces the control
device. Also, a cut-oU switch (Fig. 8) is
used to replace the mechanical trip arrange
ment of the control device.

The cut-off

switch energizes an auxilia^ relay to deenergize the main relay.

The closing speed of the arcing contact
at nominal voltage should be 5 to 9 feet per
second for the ISO MVA breakers and 9 to

12 feet per second for the 250 MVA breakers

with rated closed circuit volt^e at the

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16

!• Box Barrier Handle
2.
34.
5.

Blowout Core
Blowout Coil
Arc Kjnner
Pole Pieee

6. Stationary Arcing Contact
7.
8.
9.
10,

Boa Barrier
Are Qiute
Pole Piece
Arc Runner

11. Blowout Coil

21. Operating Rod

12. Blowout Core
13. Barrier

22. Stationary Prinary Contacts

14. Front Buahings
15. Rear Bushings
16. Frane

17. Operating Crank
18. Upper Horiiontal Barrier

19. Spring Retainer
20. Lower Horiiontal Barrier

Fig. 13
10

23. Movable Priaary Contacts
24
25
26
27
28
29.
30,

Gip Bearing
yoke

Movable Contact Arm Asseably
Movable Arcing Contact
Booster Tube
Connection Bar

Booster Cylinder and Piston

Cross Section Of Breaker Pole Unit

Magne-Blast Circuit Breaker Type AM-4.16 GEH-2000

closing coll terminals. These speeds repre
sent the average speed ol the movable arcing
contact from a point 1" before the tip Is^
tangent to the lower surface of the upper
arc runner to the tangent position.
OPENING OPERATION

An electrical opening operation is In

itiated by energizing the trip coll. This Is
accomplished either by actuating the open
ing control switch on the metal-clad unit
or by a combination of relays and current
devices used to detect a fault on the load

side of the breaker.

By energizing the

trip coil, the trip pltmger rotates the trip
latch (2), Fig. 12. causing the operating
mechanism linkage to collapse. The energy

stored In the opening springs (9 and 10) Is
thus released, opening the breaker. During
this operation, the trip coll circuit Is deenergized, and upon completion of the
opentog operation, the operating mechanism
is returned to its normal position, ready
foreclosing.

As the breaker opens, the main con

tacts part first, shunting the current through
the arcing contacts. An arc forms as the
arcing contacts part. See Fig. 13. As the
movable arcing contact (27) Is withdrawn
through the slot in the arc runner, the upper
end of the arc is transferred to the upper

arc runner (4), To assist the Interruption

at this point, a stream of air Is emitted

from the booster tube (28) and forces the
arc onto the lower arc runner (10). Estab
lishment of the arc on the runners auto

matically Inserts the blowout colls Into the

circuit, introducing a magnetic field between
the pole pieces which tends to draw the arc

away from the arcing contacts. The 250
MVA Interrupter contains one upper mag
netic blowout coll and one lower blowout

coil, each Individually connected In series
with Its respective arc runner. The arc Is
forced outward along the diverging arc
runners by the magnetic field.

At the same time, the arc Is being
forced Into the arc chute (8) which Is com

To maintain such-service. It is recommend
ed that a definite inspecUon and main
tenance schedule be set up and followed,

surfaces of the chute, elongate the arc Into

a gradually deepening serpentine path, so
that the electrical resistance in the path of
the arc is rapidly increased and the heat
from the arc Is absorbed.

The Increased

resistance reduces both the magnitude and
the phase angle of the current, and at an

early current zero the arc path is so long

and the gases produced by the arc so cooled
that the arc cannot re-establish Itself, and
interruption occurs.

the trip circuit, the manual trip (6), Fig. 1,
is used.

The opening speed of the arcing con
tact should be 12 to 18 feet per second at

rated control voltage.

reason.

When inspecting an arc chute, it

should be disassembled and the following
points noted:
1. Scale formed over the surface of the
arc chute must not be removed, but

loose particles collected in the chute
should be blown out.

This speed repre

sents the average speed over 3" from the
point when the tip on the movable arcing
contact Is tangent to the lower surface of
the upper runner.
TRIP FREE OPERATION

If the trip coll circuit Is energized
while the breaker Is closing, the trip plimger
will force the trip latch (2), Fig. 12, away
from the trip roller (3) causing the mecha
nism linkage to collapse and the breaker

to re-open. The closing armature (6) com
pletes Its closing stroke, but the closing coll

Is de-energlzed at the end of the stroke,
and the armature Is returned to Its original
position by gravity.

MAINTENANCE

or If the arc chutes are removed for any

retaining rings. All cam, roller, and latch
surfaces should be Inspected for any
evidence of damage or excessive wear.
Lubricate the mechanism as outlined below,

then, using the maintenance operating de
vice, open and close the breaker several
times to make certain that the mechanism

operates freely throughout Its entire stroke.

Cracks which have formed In the fins

Check the mechanism adjustments as speci
fied under INSTALLATION, ADJUST

of the arc chute are to be expected In

MENTS.

ceramic materials of this t^e when

breaker.

Check all terminal coonectlona.

subjected to the severe heat of an arc.
These fine cracks do not Interfere with

BEFORE ANY MAINTENANCE WORK

IS PERFORMED, MAKE CERTAIN THAT
ALL CONTROL CIRCUITS ARE OPENED
AND THAT THE BREAKER IS REMOVED
FROM THE METAL-CLAD UNIT. DO NOT
WORK ON THE BREAKER OR MECHA
NISM WHILE IN THE CLOSED POSITION

UNLESS THE PROP AND TRIP LAT^

HAVE
BEEN
BLOCKED TO

SECURELY WIRED OR
PREVENT ACCIDENTAL

TRn>PlNG.

the operation of the device in any way

BUSHINGS AND INSULATION

broken corners on the exhaust end of the

should be kept clean and unmarred to prevent
moisture absorption. If the Insulation Stir-

and should be disregarded.

Small

chute will not Interfere with Its per

face should become damaged, it should be

with either clear varnish (GE-inO) or

the

arc

chute has

suffered any

mechanical injury due to dropping or
accidental striking, resulting in the
actual breaking oU of fins, replace
ment of the chute will be necessary.

company on the basts of the number of
operations (Including switching), the magni
tude of currents interrupted, and any un
usual operations which occur from time
to time. Operating experience will soon
establish

REPAIR AND REPLACEMENT. If the con

maintenance schedule which

will give assurance of proper breaker con
On installations where a combina

tion of fault duty and repetitive operation
is encountered, an Inspection Is recom
mended after any severe fault operation.
The following instructions list the main
points to be included in an Inspection, and
a number of general recommendations.

tacts are burned or pitted, they should be
made smooth with a fine file.
After completing inspection of the con
tacts,

check the contact adjustments as

specUied under INSTALLATION, ADJUST

All other insulation parts on the breaker

should be wiped off, and if dampness is

apparent, heaters should be Installed to
insure dryness.
LUBRICATION

In order to

reliable oMrafiOn

it is important that all circuit breakers be
properly lubricated at all times. During
assemUy at the factory, all bearing sur

faces, machined surfaces, and all other
parts of the breaker and mechanism subject
to wear have been properly lubricated

using the finest g^e of lubricants avail
However, even the finest oils and
greases have a tendency to oxidize with

MENTS.

able.

MECHANISM

age, as evidenced by hardening and darken
ing In color. Elimination of the hardened

ARC CHUTES

It Is not necessary to Inspect the arc
chutes unless there Is evidence of damage

clear *Glyptal resin (GE-1202). Allow to

dry smooth and hard.

dust collected between inspection periods

By removing the box barrier the mov
able and stationary primary contacts and
the movable arcing contacts can be In
spected. The staUonary arcing contacts
can be inspected only after removing the
arc chute assembly, as explained under

sanded and cleaned, and should be reflnished

should be kept clean and dry. Smoke or

BREAKER CONTACTS

The frequency of periodic Inspection
should be determined by each operating

The surface of the Self-X bushings

formance and should be disregarded.

PERIODIC INSPECTION

dition.

Manual tripping follows the same pro
cedure except that Instead of energizing

alternately from the two opposite Inner

as serious shutdowns can often be avoided

by locating potential sources of trouble In
an early stage. A periodic lubrication of
parts subject to wear is also vitally Im
portant for the successful operation of the

the upper runner only.

posed of a series of gradually Interleaving
insulating fins. These fins, which, project

GENERAL
Dependable service and safer power
equipment are contingent upon the unfailing
performance of the power circuit breaker.

The 150 MVA Interrupter is essentially

the same as the 250 MVA Interrupter except
that It utilizes the magnetic elements In

A careful inspection should be made to
check for loose nuts or tx>lts and broken

lubricant is essential for the proper opera

tion of circuit breakers.

Also frequent

• Reg. TYade-Mark of General Electric Co.

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16
operation of the breaker causes the lubri
cant to be forced out from between the

bearing surfaces. A simple lubrication will
often clear up minor disttirbances which
might be mistakenfor more serious trouble.
A definite lubrication schedule should
be set up taking into consideration the fre
quency of operation of the breaker and local
conditions. Until such a schedule is worked
out, the breaker should be lubricated at

each periodic inspection and also whenever
it is overhauled, in accordamce with the

lubricaUon chart. Fig. 14. It is also recom
mended that all circuit breakers be operated
at regular intervals to insure the user that

the equipment is operating freely.

The lubrication chart (Fig. 14) is
divided into two methods of lubrication.
The first method outlines the maintenance

lubrication which should be performed at

the time of periodic maintenance, and re

quires no disassembly. The second method
outlines a lubrication procedure similar to

that performed onthebreaker at thefactory,
but should be used only in case ofa general
overhaul or disassembly for other reasons,

Lubrication at
Maintenance Period

Part

Alternative Lubrication

(Requires Disassembly)

Ground surfaces such as
cams, rollers, latches, etc.

Wipe clean and apply

Sleeve Bearings

Very light application of light

(Mechanism and Breaker

Linkage)

Wipe clean and apply DS0H15.

DSOHlSe

machine oil SA£>20 or -30.

Remove pins and links and clean
as per cleaning instructions.

Apply D50HIS liberally.

Removable Seal and Open
Type Ball, Roller and

Needle Bearings

Light application of light
machine oil SAE-20 or -30.

Clean as per cleaning instructions
and repack with DS0H15.

Wipe clean and apply

Wipe clean and apply D$0H47. **

Silver Plated Contacts and
Primary Disconnect Studs

D50H47e

Arcing Conacts

Do not lubricate.

1. Cup Bearing

No lubrication required.

Wipe clean andapplyD50H47** except!

2. Loose rings between

Kg lubrication required.

Replace rings showing evidence

of excessive wear.

{

No lubrication required.

••

CONTACT ARM HINCE
ASSEMBLY

on highly repetitive duty.

bushing and contact arm.

poster Cylinders

or if the operation of the breaker becomes
slower.

Fig. m

Lubrication Chart

General Electric Lubricant D50H15

and DS0H47 are available in 1/4# collapsible
tubes. It is so packaged to insure cleanliness

If it becomes necessary to

contacts indicate the probable need

METHOD OF CLEANING BEARINGS

thinner) be sure the alcohol is perfectly
clean, and do not allow the bearings to

Wherever cleaning is required, as in
dicated in the lubrication chart, the follow
ing procedures are recommended:

remain in the alcohol more than a few
hours.
If it is desirable to leave the

for arcing contact replacement). If
the contact surfaces are only rough
ened or galled, they should be

filed.

bearings in the alcohol for a longer time,

contacts should be greased lightly

Sleeve Bearings

an inhibited alcohoi such as is used for
anti-freeze should be used. Even then the
bearings should be removed from the alcohol

4. Arcing Contacts - When the arcing

and to prevent oxidation.

NOTE:

clean

The pins shotild be removed and all old

oxidized grease removed by Immersion in
clean petroleum solvent or similar cleaner.
DO NOT USE CARBON-TETRACHLORIDE.

Wipe the bearing clean.

Apply a small

amount of G. E. Lubricant DS0H15 to the

entire surface of the bearing and pin just
before reassembling.
Removable Seal and Open Type Bail, Roller
and Needle Bearings

The bearings should be first removed

from the mechanism and disassembled by
the removal of the seals or inner race In

the case of needle bearings. They should
then be placed in a container of clean
petroleum solvent or similar cleaner. DO
NOT USE CARBON-TETRACHLORIDE. H

the

bearings

in alcohol (shellac

within twenty-four hours.

Esso Anti-

Freeze and Du Font aerone are satis

factory for this purpose.
against the

Precautions

toxic effects of the alcohol

must be exercised by wearing rubt»r gloves

and by using the alcohol in a well ventilated

are inducive to corrosion. If the bearings
moved by washing in alcohoi.

After the

Marings have been thoroughly cleaned, spin

them in clean new light machine oil until
we cleaner or solvent is entirely removed,
^low this oil to drain off and then repack
GE.
metal

Lubricant
parts
are

D50HI5 being sure all
^eased. The removable seals should then
be replaced.

After contact dressing the

with D50H47.

contact wipe is less than the mto-

imum specified under "Adjustments",
the contacts should be replaced. The
contacts should be inspected for un

even wear and/or damage using a
mirror to Inspect the stationary con

room; excessive exposure to the fumes is

tacts. Norm^y it will not be neces

sometimes unpleasant to personnel. Wash

sary to remove the arc chutes for

ing the bearings in light oil and draining
should follow immediately then apply the
lubricant.

RECOMMENDED MAINTENANCE FOR
MAGNE-BLAST BREAKERS APPLIED TO
REPETITIVE SWITCHING DUTY

Magne-blast breakers applied to re
petitive operation such as switching arc
furnaces, capacitors and motors should be

the grease in the bearingshas becomebadly serviced and maintained according to the
^dized it may be necessary to use alcohol following schedule:
(type used for thinning shellac) to remove
it. Ordinarily, by agitating the bearings in A. Every 2000 Operations, or Every Six
the cleaning solution, and using a stiff
Months - Whichever Comes First
brush to remove the solid particles, the
t>earlngs can be satisfactorily cleaned. Do
1. Remove the box tarriers and oper
not handle the bearings with bare hands as
ating mechanism covers.
deposits from the sldn onto the bearings

are touched, the contamination can be re

smoothed with crocus cloth or draw

2. Wipe all insulating parts, withaclean
dry cloth, including the bushings,
clean of smoke deposit and dust,
also the inside of the box barriers.

3. Primary Contacts - Inspect the con
dition of the stationary contact fingers

and movable contact blocks.

Badly

pitted or burned contacts should be

replaced.

(Note:

Burned primary

this 2000 operation servicing unless
inadequate wipe or contact conditions
indicate aneedfor replacement. When
the are chutes are removed, the con
tact braids, coil protectors, and other
parts subject to arcing should

checked for possible cleaning or
replacement.
Do not grease the
arcing contacts under any circum
stances.

5. Check the breaker and mechanism

adjustments as

summarized under

"Final Inspection & Test".

The

necessary readjustments should be
made as described under "Adjust
ments".

6. The breaker and operating mech
anism should be carefully inspect

ed for loose nuts, bolts, retaining
rings, etc., all cam, latch and roller
surfaces should be inspected for
damage or excessive wear.
The
buffer

blocks

and

their

retainers

on the bottom of the stationary con
tact support should be inspected for
possible need of replacement.
7. The main contacts of the control de

vice should be inspected for wear and
possible replacement.

Magne-Blast Circuit Breaker Type AM-4.16 GEH-2000
8. Lubricate

the

breaker

operating

wires and see that all binding screws
are tight.

C. Every 20,000 Operations or Approxi

mechanism In accordance with the

mately Every Five Years - Whichever

table under paragraph heading "LUB
RICATION".

Comes First

Damaged or dirty

contacts

In trip

circuit.

9. Inspect all wiring lor tightness ol

1. At this time the breaker should be

connections and possible damage to

given a general overhaul and all
excessively worn parts in both the
mechanism and breaker replaced.
Such wear will usvally be Indicated
when the breaker cannot be adjusted

insulation.

10. After the breaker has been serviced,
It should be closed and opened slowly
with the maintenance closing device
to be sure there Is no binding or

to Instruction book tolerances.

can move to the fully opened and fully
closed positions. Its electrical oper
ation should then be checked using

tacts.

FAILURE TO CLOSE OR LATCH CLOSED

Mechanism binding or sticking caused
by lack of lubrication.
REMEDY: Lubricate complete mecha

Mechanism binding or sticking caused
by being out of adjustment.

This

overhaul and Inspection is more de
tailed and will require disassembly
of mechanism and breaker operating

friction and that the breaker contacts

REMEDY: Recondition or replace con

nism.

parts.

REMEDY:

either the test cabinet or the test

couplers.

amine latch and roller surfaces for

with G. E. Lubricant D50H1S as des
cribed under "Lubrication".

3. The cup bearing at the hinge point of

B. Alter Every 10,000 Operations
1. In addition to the servicing

rlcated with G. E. contact lubricant

D50H47.

2. All areas in the throat area of the

arc chute assembly which are con
taminated by arc products should be
thoroughly cleaned by using sand
paper. This cleaning should t)e per
formed any time the arc chute is
removed.
The arc chute fins should
not be cleaned.
Whenever the arc

when reduced in thickness to less
than 1/32".

4. The stationary primary contact fin
gers should be disassembled and the
silver-plated pivot area of the contact
and contact support cleaned and lub

5. The breaker and operating mechan

dirt should tie blown out before re

for every 2,000 operations and properiy adjusted before being put back

blow-out coils should be care

from each other the coils

4. The arc runners should be inspected

and replaced when any part of their
area has been reduced to 25% of the
original metal thickness as a result
of arc erosion.

5. Check the stationary arcing contacts
to assure that the arcing contacts are

TROUBLE SHOOTING

from arc action and heat so that the

should be replaced. All connections
should be checked for tightness.

Into service.

fully examined and if the insulation
has been cracked, shrunk or eroded
sulated

ism should be serviced as described

placing arc chutes.

turns of the coils are not fully in

tacts.

ricated with G. E. lubricant D50H47.

removed, loose dust and

Failure of a breaker to operate properly
will generally fall within three general
classes: Failure to trip, failure to close
or latch closed, and overheating.
The
following Is a brief outline showing parti
cular types of distress that might be en
countered, together with suggestions for
remedying the trouble:

nections are tight.

tions.

11. Insufficient control voltage caused by

poor regulation (a-c control),
REMEDY:

and cannot be satisfactorily cleaned

Mechanism binding or sticking caused
by lack of lubrication.
REMEDY; Lubricate complete mecha

sure it
supply.

REMEDY:

Check all

to be

Is delivering adequate d-c

amine latch and roller surfaces for

should be replaced.
NOTE: Fine cracks may develop In

corrosion.

should be reconditioned very carefully
and only when absolutely necessary).
2.

Contacts not properly aligned or ad
justed.

the fins of the arc chute sides. This

terials when subjected to the high heat

Poor condition of contacts due to lack

REMEDY:
Recondition or replace
burned and pitted contacts. (Contacts

mechanism ad

latches, stops, auxiliary

devices, etc.. In accordance with IN
STALLATION, adjustments. Ex

ed and/or erc^ed from arc action

REMEDY: Check all adjustments In

Damaged trip coll.
REMEDY: Replace damaged coll.

accordance with INSTALLATION, AD
JUSTMENTS.

possibility of fin sections breaking

Blown fuse in trip circuit.
REMEDY: Replace

completely off. Small broken corners

blown fuse after

determining cause of failure.

on the exhaust end of the arc chute will

can also be disregarded.

control

rectifier

of attention after severe duty or too
frequent operation.

by being out of adjustment.

7. Any parts damaged or severely burn

not interfere with its performance and

larger

OVERHEATING

Mechanism binding or sticking caused
justments,

of an arc and may be disregarded
unless they are long and present a

Check

nism.

should be replaced.

is to be expected with ceramic ma

Install

transformer.

6. Insulating material that Iscarlmnized

Damaged control device coll.
REMEDY: Replace damaged coll.
Damaged closing coll.
REMEDY: Replace damaged coll.
Defective cut-off switch, lateh-checkIng switch, or Interlock switch.
REMEDY: Replace defecttve switch.
Blown fuse In closing circuit.
REMEDY: Replace blown fuse after
determining cause of failure.
Faulty connections In closing clrcuiL
REMEDY: Repair broken or loose
wires and see that all binding screws
are tight.

10. Insufficient control voltage caused by
excessive drop in leads.
REMEDY: Install larger wires and
improve electrical contact at connec

FAILURE TO TRIP

In good condition and that their con

Damaged or dirty contacts In control'
circuit. Including control device.

REMEDY: Recondition or replace con

bushing may be lubricated for pro
longed life. The contact rings should
be inspected for wear and replaced

and arc runners.

3. The

point between the contact blade and

and disassembled to permlta detailed
inspection of insulation, blowout coils

Contact rings at the hinge

Control device sticking or not oper
ating properly.
REMEDY: Check and adjust control
device, or replace.

bled. Inspected, cleaned and re-lub-

done

should be removed from the breaker

chute

corrosion.

the contact blade should be dlsasem-

each 2,000 operations, the arc chutes

Check all mechanism ad

justments, latches, stops, auxiliary
devices, etc., In accordance with IN
STALLATION, ADJUSTMENTS. Ex

2. The trip roller and trip shaft bearings
In the operating mechanism should be
disassembled, cleaned and repacked

Faulty connections in trip circuit.
REMEDY: Repair broken or loose

Breaker kept closed or open for too
long a period.
REMEDY: Operate breaker more often
to wipe contacts clean. Replace con
tacts If necessary.
13

GEH-2000

Magne-Blaat Circuit Breaker Type AM-4.16

2K5E!

1. Sfrtr Bushing
2. Supporting Bolt

J. Opp«r Uountinx Support
4. Stationary Arcing Qsncact Aaseably
5.
6.

Movable Arcing intact
Aaseetbiy Bolts

Brace for Arc Oiute

1.
2.
34.

8. Are Oujte Mounting Bracket
9. Lowr Supporting Bolt

10. Cover Mounting Support

Fig. tS

logo, or re-arrange circuits so as to
remove excess load.

Primary connections of inadequate ca
pacity.
REMEDY;

Increase size or number of

conductors or remove excess current.

11. Asseabiy Bolt
12. Side Shield

5. Side Brace

14. Lover Mounting Support
15. Assembly Bolts

8. Lover Brace

16. Assembly Bolts

Arc Chute Partially Reaoved Show

adequate rating (or present or future

9. Mounting Slot
10. Upper Mounting Support

7. Assembly Bolt

Fig. 16

ing Accessibility of Arcing Contacts

Overloading.
REMEDY: Replace breaker withoneof

A.aexbly Bolts and Bushing
Assrably Bolts
Upper Pole Piece
Assembly Bolt

ARC CHUTE

Jirc Chute A.senbly ConiDlete (ISO mva. 2S0 nva)

(To Inspect or replace

6. At this point the fiber side shields (6),
Fig. 18, the upper arc runner assembly
(4) and lower arc runner assembly (7)

blow-out coUs)

To remove an arc chute, first open the

breaker and remove the box barrier (7),
Fig. 13. Loosen the two upper supporting
bolts (2), Fig. 15, and Che one lower sup

can be removed.

7. Further disassembly of both the upper
and lower arc runner assemblies can be

porting bolt (9) using a 3/4" wrench. By

done by removing the various screws

raising the compiete arc chute assembly

and 1/4" assembly bolts (not Illustrated)

about 3/8" and sliding it toward the rear

as shown in Fig. 17.

of the breaker it can be removed as shown

in Fig. 15.
6.

8. The arc chute sides (6), Fig. 17, can be
separated by removal of assembly bolts

Loose connections or terminal con
To disassemble the arc chute after it

nections.

(2 and 4). Fig. 16.

has been removed from the breaker, pro

REMEDY: Tighten.

ceed as follows:

Reassemble the arc chute in the reverse

Ambient temperature too high,

order. The following items should be noted

REMEDY: Relocate in a cooler place,
or arrange some means of cooling.

during reassembly:

1. Remove the assembly bolts (7, 9, U
and 13), Fig. 16,

1. Equally space the fins of the arc chute
sides before bolting together.

REPAIR AND REPLACEMENT

2. Remove the side brace and pole piece

The following information covers in
detail the proper method of removing vari
ous parts of the breaker in order to make

any necessary repairs. This section in
cludes only those repairs that can be made
at the Installation on parts of the breaker
that are most subject to damage or wear.
IMPORTANT:

UPON

COMPLETION OF

ANY REPAIR WORK, ALL BREAKER AND
MECHANISM
CHECKED.

ADJUSTMENTS
Refer

MUST

to the section on IN

STALLATION, paying particular attention
to ADJUSTMENTSand FINAL INSPECTION.

assembly (5), Fig. 16.

Check to insure that electrical connec

tions

to the blowout coils are tight.

3. To remove the upper mounting support

(10), Fig. 16, remove the assembly
bolts (I) and connection screw (2),
Fig. 18.

4. Remove the assembly bolts (16), Fig.

3. When reassembling the arc runner as

semblies, check that the spacers (1 and
13), Fig. 17, are correctly Installed.
4. Before bolting the upper mounting sup

lower brace (S).

port in place, make certain that the
upper are runner assembly is tight

5. Remove the lowermountingsupport(14).
Fig. 16, by removing the assembly
bolts (15) and the connection nut (9),

against the arc chute side so chat the

Fig. 18.

remove

the

gap between the upper insulation (7),
Fig. 17, and the arc chute aide (6) Is
a minimum.

Magne-BIast Circuit Breaker Type AM-4.15
S.

Make

ceruin thai

GEH-2000

the electrical con

nections (2 and 9), Fig. 18, are tight.
To reassemble

the arc chute to the

breaker, proceed as follows:
1. Rest the lower mounting support (10)
on the arc chute mounting bracket (8)
as shown in Fig. 15.
2.

Slide

the arc chute forward and lift

it slightly to engage the supporting

1. Upper Arc fiunner Spicers

bolts (2), Fig. 15, in the sloU of the
upper mounting support (3).

3.
4.

Blosaut Coil

3. Tighten the supporting bolts (2 and 9),

Insuletion

Fig. 15.

the

2. Upper Arc Runner Assembly

These bolts serve as bo^

electrical and mechanical connec

tions between the bushing and the arc
runners.

Blovout ^re

Upper Arc ^nner

Arc Chute Side

Upper Insulation

Lower Arc Runner

10. Blowout Coil
It.

Check that the movable arcing contact

Blowout Care

12. Lover Arc Runner Asaesbly

(5), Fig. 3, passes through the slot in
the upper arc runner (6) without touch

13.

Lower Coil Connection

14. Lower Arc Runner Spacers

ing.

TRIP SHAFT BALL BEARINGS
1. Remove mechanism cover.

2. Remove mounting bolts for control
device, Fig. 1, Part 7, letting con
trol device hang free.
Do not
remove wiring.

_?J ^

3. Remove the trip coil frame mount

ing bolts. Fig. 24, Part 2, letting
frame hang free. Also, removetrip
coil leads from terminal boards.

Fig, 24, Part 4.
4. Remove the trip coil and plunger

Fig. 17

Ire Chute Assenbly with Side Aeiraved

bracket from trip shaft using snap

ring pliers on ring holding trip coil
plunger assembly.
5. Remove switch bar, Fig. 23, Part 5,
from latch shaft and snap ring and

washers near bearing.

S. Remove stop bar. Fig. 32, View A,
Part 282, for manual trip rod.
Also, remove snap rings and wash
ers next to

7. Using a

bearing on left side.

brass rod approximately

15" long and 3/8" diameter, drive
each bearing out, taking the right one
out first using the opening in the
left side of the mechanism frame and

1. Upper Counting Support

the left one out from the opening
made from the removal of the right

2. Connection Bolt
3. Upper Blowout Coll

hand bearing.

4. Upper Arc I^nner Asaosbly
5. Upper Arc Ibjnner
6.

Side Shield

NOTE; When removing the lefthand
bearing, brass rod as mentioned
above may have to be bent in order

Lower Coil Garsiection

to clear latch.

Connection Nut

7. Lower Arc Runner Assenbiy
10. Lower hunting Support

To reassemble, reverse the above

procedure except to drive bearings
back in the

mechanism frame,

pipe should be used so as not to
damage bearing surface.
NOTE;

If latch is to be replaced,

Che iirst seven steps as listed above
should be followed.

Also remove

the set screw holding the latch on

shaft then place block between latch
and frame

to stop movement, and

drive shaft out of latch. When re

placing,

make

sure spring is in

proper place and one half turn has
been made to wind spring. Also,
make sure latch is in place on stop
bar roller before bearings and shaft
are reassembled.

^10*

Front View Arc Chute Assembly

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16
TRIP LATCH ROLLER BEARING

the round end of spring guide in cut

out in primary finger (Fig. 20C>.

1. Remove mechanism cover.

Hold spring assemblyflrmly in place
and remove spring compressor.

2. Remove mountinf bolts on control
device, Fig. 1, Part 7. leaving con
trol device hang free.

Do not re

move wiring.

C. Movable Arcing Contact (7), Fig. 21.
1. Remove the assembly bolts (8).

3. Place block between manual trip rod
Fig. 1, Part 6, and stop bar on trip
shaft.

This holds trip shaft in trip

position and allows trip linkage to

be free.

4. Working through hole on left hand
side of mechanism, remove snap
ring and washer from trip roller
pin, Part 289, Fig. 32, View C,

Reassemble in reverse order.

D. Movable Primary Contacts (5), Fig. 21.

(1200 Amp. Breaker)

1. Remove the nuts from assembly

using snap ring pliers.

bolts (6).
Remove the primary contacts and

Reassemble in reverse order.

spacers (not illustrated).

5. Slide trip roller pin, Part 289,
Fig. 32, just enough to the right to

(2000 Amp. Breaker)
1. Remove the nuts from assembly
bolts (6).
2. Remove the connection bar (9).

allow room to hook snap ring pliers
on ring on other end of pin. Com

press pliers to free snap ring and
pry the pin to the left with screw

Remove the cup bearing (3).

snap ring.

Spread the contact arms (4) and
remove the primary contacts (5).

removed for lubrication (see section

Reassemble in the reverse order.

driver to complete the removal of

6. Trip roller bearing can now be
on LUBRICATION). Particular at
tention should be paid to the location

of washers and spacers.

7. To reassemble, reverse the above
procedures.

3. Bolts for Contact Support
4. Cbntact Support
5. Bolt for nezible Braid
6. Mounting Bolt

CONTACTS

Open the breaker and remove the box

barrier and arc chutes as previously des

cribed.

E. Contact Blade Assembly (4,5;7), Fig. 21
1. Bear Bushing
2. Guide snd Support for Arc Qiute

To remove the contacts, proceed

as follows:

7. flexible Braid
8. Connection Bolt

11. Spring Baffle^

Disconnect the contact braids from

contact fingers by removing two

Fig. 19

9. Stud for itaunting Arcing Fingers
10. Stationary Arcing Contact Asaeably

Remove the connection bar (9).
Remove the cup bearing (3) and
the pin (2) Fig. 4.
When reassembling, first insert the
piston assembly (10), Fig. 21, Into
the tiooster cylinderandreassemble
the cup bearing (3).
Replace pin (2), Fig. 4, and con
nection bar (9), Fig. 21.

F. After disassembly ana reassembly of
any contacts, check all contact adjust

A. Stationary Arcing Contacts (10) Fig. 19
1.

1.
2.

Rear Bushing Assembly

ments as described under INSTALLuA-

TION, ADJUSTMENTS.

bolts (8), Fig. 19.

Grasp the lower end of the contact

fingers with pliers and pull contact
assembly downward to remove from
stud assembly.

To disassemble braids from stua
assembly, remove one bolt (5).

4. To aisassemble stud assembly from
contact support, remove two bolts

(6).

Reassemble In the reverse order.

B. Stationary Primary Contacts (9), Fig.20
1. Compress the contact spring (6).
2. Remove spring and spring guide (1).
3.

Raise the contact finger to clear
the primary contact stop plate (8)
and lift the finger outof contact suo-

port (7).

To replace the Stationary Primary Con
tacts;

Apply a thin coating of DS0H28

—

grease on the hinged end of the fin

ger (9) then place it on contact sup
port (7) so that it is retained by slot)

2.
3.

plate (8).

Open spring compressor (3) and as
semble spring guide, spring and
spring compression (Fig. 20A).

Turn handle (2) in clockwise direc

tion to compress contact spring

(Fig. 20B). Hold spring firmly in

1. Spring Cuide

yoke on spring compressor to pre
vent the spring from slipping out of

the compressor.

4. Place washer (not shown) on guide

2. Rendle for Spring Coopresior
3. Spring Qsopresior
4-

on top of spring, place top of guide

into hole in .spring retainer (4) and

Spring Retainer

S. Aaaetrbiy Bait for Spring Reteinar

Fig. 20

6. Spring
7. Contact Support
8. Stop FlaEe

9. Stationery Prinery
Concept Fingera

Method of inatalling prJnery Contact Springe Ueing a Spring Cooipreseor

Magnc-Blast Circuit Breaker Type AM-4.16 GEH-2000

a- ' I

wmjhjh

-1'

Contact Springs

«• N

Stationary Priwary Contacts ' -

Cup Bearing

Contact Am

yovsble Prioary Contacts
Assembly Bolts
Movable Arcing Cantact
Assembly Bolts

I. Solenoid Pot

7. Closing Anseture

2< Terminal Board
*. Boctoai Plate

8. Stop Nuts
9. Front Stud Nuts

10. Plunger Guide
11. Closing Coil Leads

5. Control Device Trip
Plunger Rod

12. Stop Nuts

6. Ouide Studs

Connection Bar

Piston Asaembly

Ig. 21

Fig. 23

Closing Solenoid Assembly

Reroval of Contacts

BUSHINGS
IMPORTANT:

viously described.

DO NOT REMOVE ALL

SIX BUSHINGSaTONCE. The bushings have

been carefully ali^ea with

Disassemble the spring retainer (4) by

Re/erring to Fig. 19, disassemble the
contact support (4) ana arc chute mount
ing bracket (2) by removing two bolts

Reassemble in the reverse order. The

the breaker

frame, during assembly at Che factory, and it

Is important that this augment be maintain
ed to facilitate Installation of thebreakerin
the metal-clad unit. It Is therefore recom-

menueci that the bushings be removed and
reasseir.blea one at a time.

Referring to Fig. 20, disassemble the

primary contact springs (6) as pre
removing mounting bolts (5).

(3).

arc chute mounting bracket (2) is not
symmetrical ana must be assembled
correctly to orient the arc chute
properly on the breaker. The longest
projection of the bracket should be

Also, before

removing any one bushing, measure the
distance from that particular bushing to ad
jacent bushings In both directions, so that it
may be re-lnstalled in the same location.

towara the lower end of the bushing.
It is also possible to remove ana reassecDble three bushings at one time. If

Front Bushing

this is preferrea, alignment of the bushings
may be accomplisheo by placing the breaker

barrier anu arc chutes as already aes-

before Cightenlngthe bushing mounting bolts.

cribed.

This

must be done before the arc chutes

are re-installeu

To replace me bushing, proceed as
follows:

Remove the connection bar (9), Fig.

21, and cup bearing (3).
Remove the four bolts at the mounting

flange of the front bushing being removea, and lower the bushing.

2.
3.
4.
5.
22

Sear Bushing
Counting Bolts
Upper Horizontal Barrier
Lover Horizontal Barrier
Rear Viea of Breaker vith One
Arc Cfiute Rencved

Open the breaker ana remove the box
barrier

ana

arc

chutes as already

Remove the upper anu lower horizontal
barriers (4 ana 5), Fig. 22.

contact blade and cup bearing should

have a thin coating of •S0H47 grease.

Remove the four bolts (3) at the mount

ing flange of the rear bushing being
removed and lower the bushing assem

'Vhen reassembling, first mount the
bushing and assemble the cup bearing

(3) and contact arm (4), Fig. 21. The
contact surfaces at the hinge point of the

describea.

bly.

Remove the upper and lower horizontal
barriers (4 and 5), Fig. 22.

Rear Bushing
1. Front Bushing

Open the breaker and remove the box

in a de-energized spare metal-clad unit

Check all contact adjustments as out

lined under INSTALLATION, ADJUSTMENT3.

GEH-2000

Magne-Blast Circuit Breaker Type AM-4.16

m
2

1. Trip Coil Support
3. Uounting Bolts
1.

fig. ZS

Pivot Pin

3. Trip Coil
4. Trip Coil Leads

Potential Trip Coil

2. OpeninR Spring Unit
3.

Pivot Pin

4. Trip Coil Mounting Plate
5. Terminal Board
6.

Switch Bar

7. Trip Oril Plunger Bracket

Fig. 24

Opening Spring Issendly

CLOSING COIL

The closing coil is contained within

the solenoid |X3t (1), Fig. 23.

Open the breaker.

control device plunger guide (10) and

Remove the terminal board(2)fromthe

Tilt the bottom plate downward and
replace the solenoid pot (1) and two

Tighten the four nuts under the bottom
plate taking special precaution to center

the closing coil around the pole piece.
If the closing coil is not firmly held

in place, add spacers above the closing
coil.

reassembling (in the reverse

adjustment as explained under fNSTAL*
LATION, ADJUSTMENTS.

(5). Note: For ease in removing the
closing coil and bottom plate (step 5)
the armature and plunger assembly
can be removed from the mechanism

Loosen the lour nuts under the bottom

the bottom plate with a rope sling or
hoist and remove the two rear nuts.

10.

Recheck the mechanism adjustments

explaineo unuer INSTALLATION,

remove the interlock switch (3)

remove the two mounting screws

(4) -and disconnect the lead wires.

assemble in the reverse order and check

LATCH CHECKING SWITCH

To remove the latch checking switch
(6), Fig. 6, (when furnlshea), remove the
two mounting screws (8) and disconnect
the lead wires.

adjustments.

Reassemble in the reverse

TRIP COIL

oraer and check the switch adjustments as
explained under INSTALLATION, ADJUST

To replace the potential trip coil (3),
Fig. 2S, proceed as follows:

CUT-OFF SWITCH

MENTS.

Open

the

breaker

and

remove

the

opening spring unit (2), Fig. 24, by
removing the pivot pins (1 and 3).

front studs. This permits the bottom
plate, closing coil, solenoid pot (1)
to be removed.

Replace the control device trip plunger
rod (5) and armature (7).

Remove the nuts (9} at the top of the
and control device plunger guide (10)

Fig. 6,

INSTALLATION, ADJUSTMENTS.

by removing the four bolts on the under
side of the armature plate.

plate (4) approximately 1/2". Support

INTERLOCK SWITCH

the switch adjustments as explained under

Remove the stop nuts (8 and 12) on
guide studs (6), lower the armature

plate (7) and control device trip plunger

After

order) check the primary contact gap

wires.
Also, remove the wire from
band (3).

Remove the trip coll (3).

Remove the two closing coil leads (II).

solenoid pot and let It hang by the

the trip coll support (1).

upper pole piece.

front studs and nuts (9).
2.

Remove the two mounting bolts (2) and

compressing the piston ring on the

To remove

the closing coil, proceed as follows:
1.

To reassemble, first place the closing
coil and spacers on the bottom plate
(4). Raise into position, inserting the

To remove the cut-off switch (1),
Fig. 3, remove the two mounting bolts and
disconnect

the

lead

wires.

When reas

sembling, check the cut-off switch adjust

Disconnect the two irip coil lead wires
(4), Fig. 25.

ment as explained under INSTALLATION,
ADJUSTMENTS.

Magne-Blast Circuit Breaker Type AM-4.16 GEH-2000

RENEWAL PARTS

It is recommended that suificient renewal parts be carried in stock to enable
the promptreplacement ofany worn, broken,

minimizes service interruptions caused should be carried, the amount depending
by breakdowns, and saves time and ex- upon the severity of the service and me
pense. When continuous operation is a time required to secure replacements,

or damaged parts.

primary consideration, more renewal parts

A stock of such parts

Note; The listed terms "right" and "left" apply when facing the solenoid mechanism endof the breaker.
ORDERING INSTRUCTIONS

ALWAYS SPECIFY THE COMPLETE NAMEPLATE DATA OF BOTH THE BREAKER AND
THE mechanism.

SPECIFY the QUANTITY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF
LISTED), AND DESCRIPTION OF EaCH PART ORDERED, AND THIS BULLETIN NUMBER.

STANDARD HARDWARE, SUCH AS SCREWS, BOLTS, NUTS, WASHERS, ETC., IS NOT
LISTED IN THIS BULLETIN.

SUCH ITEMS SHOULD BE PURCHASED LOCALLY.

FOR PRICES, REFER TO THE NEAREST OFFICE OF THE GENERAL ELECTRIC
COMPANY.

ILLUSTRATION REFERENCE

Page
Arc Chute

FIG.

Control Device for All Mechanisms

FIG.

Cross-sections - Type AM-4.16-3

FIG.

Impact Trip Device for All Mechanisms
Interlock Plunger

FIG.

Maintenance

FIG.

Closing Device

Movable Contact Arm Assembly

FIG.

MS-13 Mechanism-Cross-section, Details, Spring Asm.

FIG.

MS-13 Mechanism, Front View, Right and Left Side View
MS-13 Mechanism, wim Current Trip, Partial View
Rear Bushing Assembly
Secondary Disconnect Device and Mechanism Parts
Undervoltage Device

HG.

FIG.

Magne-Blast Circuit Breaker Type AM-4.16

GER-2000

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

parts are listed on the foUWSg pagel
FIG.
NO.

REF.
NO.

RATING IN

MVA

AMPS.

ALL
ALL
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

250, 250A
ALL

250,
250,
ISO,
250,

132
132
155

ALL
ALL
ALL

ISSA
156
158
159
160
160
160
160
165
165-

ALL

ALL
ISOA

150, 150A
250, 2S0A
ALL
ISOA

1200
1200
2000

738
753
753
753

ALL
ALL

753

ALL

165
168
168 .
168
168

ALL

150A

150, ISOA
250, 250A
ALL
ALL

211

212"'

150A

212 V212 .

150, 150A

250, 2S0A

212J

ALL

213>
213 f
2131

ISOA

150, ISOA
250, 250A

213/'

261
261!^
261
261
370
370
370
370
..370
663
663663

ALL

250,
ISO,
250,
150,

^38

Not shown

600

600
1200
1200
2000
600
1200
1200
2000
ALL
600
1200
1200
2000
600
1200
1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

150, ISOA
250, 250A

165

250A
250A
150A
250A

250A
ISOA
2S0A
ISOA

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

maintenance. Other

CAT. NO. FOR TYPE
AM 4.16 (MVA)-3

NO. PER
BREAKER

263B293 P-2
281B708 G-4
414A116 P-2
414A117 P-1
383A932 P-l
2S8C616 P-g
421711 P-l
407193 P-l
258C616 p. 13

Booster Cylinder
Operating Rod
Insulation Plate

Upper Runner Instilation Bottom

Lower Shield

Upper Runner Insulation
Insulating Cup
Washer

Lower Barrier
Lower Barrier

258C616 P-6
236C791 G-1

Flexible Conn. (Right)
Flexible Conn. (Left)
Sta. Arcing Contact Assembly

236C791 G-4
236C790 G-9

414A116 P-4
6445087 P-2

Insulating Plate
Buffer

414A180

Primary Contact Finger Spring
Primary Contact Finger Spring
Primary Contact Finger Spring
Primary Contact Finger ^ring

414A180

6509787 P-l
6509787 P-l
236C791
236C791
236C791
236C791

6557243
6557243
6557243
6557243
802B742

P-8
P-8
P-8
P-8

Primary Contact Finger

Primary Contact Finger
Primary Contact Finger

P-l
P-l
P-2
P-2
G-3

Clamp for BuUer
Clamp for Buffer
Clamp for Buffer
Clamp for Buffer

6S91C44 P-7),,,-<»/

650t6S-P=7-V"^'
0591C44 P»7 I

8591-e44-P=8
6501044-P--8

CS01044 P.:a

6501044 P-eJ
6375521 G-2
6375521 G-6
6375521 G-1
6375521 G-S

6174582 G-1
6174582 C-2
6174582 G-14
6275070 G-1
6275070 G-2
6275017 G-19
6275017 G-20
6275017 G-33
6174599 G-2
6174599 G-6
6275017 G-19

6275017 G-20
6275017 G-33
6275017 G-34

DESCRIPTION

IHA'i'i

i'-i

Movable Arcing Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact

Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Closing coil (T26v d-c)
Closing coil (125v d-c)

Closing coil (250v d-c)

Closing coil (250v d-c)
Potential trip coil (125v d-c)
Potential trip coil (2S0v d-c)
Potential trip coll (230va-c)
Potential trip coil ( 24vd-c)
Potential trip coil ( 48v d-c)
UVD Coil (125v d-c)

UVD Coil (250v d-c)

UVD Coil (230va-c)
Current trip coU (3 Amp. a-c)

Capacitor trip coU (230v a-c)
Control device coil (125v d-c)
Control device coil (250v d-c)
Control device coil (230v a-c)

(continuous)

Control device coll (230v a-c)
(intermittent)

Magne-Blast Circuit Breaker Type AM-4.I6

•»

GEH-2000

«.i

Jli

^IJIA
: :-sio6

-=•=

123

108

'28

i07
,_Q

7f7^.

tV.JkT^K •—122
-122
— iZ9fl
— 127
— 129

Figi 264

Cooplete Asseebly
(250 mva)

F>g> 266

Fig. 26

Side Cover Aenoved

Fig. 26C

Front View

Arc Chute (Ref. do. 100)

PARTS REFERENCED IN FIGS. 26A, 26B & 26C

CAT. NO. FOR

DESCRIPTION

AM-4.16-(MVA)-3
100
100
101
102
103
104
104
105

106
107
108
109
110
111

150, 150A
250, 2S0A
All

All
All

150, 150A
250, 250A
All
Ail
AU
All
All

250, 250A
All

112

250, 250A

113
114
115
116
117

All

118

119
120
121
122
123
124
125
126
127
128

129
129A
130
131

I31A
132

132

All

AU
AU
AU
AU
AU
All
All
AU

250, 250A
All
AU
All

All

All
All
AU
AU

AU
AU

250, 2S0A
150, 150A

All
AU
All
All
All
All
AU
AU
AU
All
All
AU
All
AU
All
All
AU
AU
AU
All

215D469 G-1

21SD469
456A381
264B100
258C616
2150469
215D469
6176J09

G-2
P-i
G-3
P-4
G-8
G-9
P-7a

258C615
258C615
258C616
258C616
258C615

G-2
P-29
P-18
P-2
G-6

421A208 P-93
258C615 G-3
258C615 G-1

258C615 P-11
421A209 P-82
432249

P-I

414A116 P-2

Arc chute asm., complete
Arc chute asm., complete
Brace
Arc chute sides

Lower support
Upper support
Upper support
Spacer

Upper pole piece (right)
Core

Core Insulating tube
Shield

Lower pole piece (right)
Spacer

Lower pole piece (left)
Upper pole piece (left)
Connection

Spacer
Spacer
Insulation plates

All

414A117 P-1

Upper runner insulation bottom i

All
AU
AU

366A743 G-1
688C512 G-1
258C616 P-5

Coil (upper)

All

258C616 P-11
366A744 G-1
421A208 P-434

AU
All
AU

2S8C615 P-I5

Runner (upper)
Spacer
Spacer

CoU (lower)
Spacer
Support

All
All

383A932 P-1
258C615 G-5

All
AU

258C615 G-4
2S8C616 P-22

AU
AU

258C616 P-21

^acer

258C616 P-9
421711
P-1

Insulating cups

407193
P-1
25SC616 P-6
25aC6I6 P-13

Lower barrier
Lower barrier

All
AU
All
AU

Lower shield

Connection assembly
Runner (lower)
Spacer

Upper Insulation

Washer (for Insulating cup)

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16

i
,9

22 33

33 22

UrJ

a
SECTIONS AA

(2000 AMP)

T
(1200 AMP)

Fia. 27
22

Cross-section Type 4H-it,16-3

Magne-Blast Circuit Breaker Type AM-4.16 GEB-2000
PARTS REFERENCED m FIG. 27

CAT. NO. FOR

'I •

DESCRIPTION

AMPS

All

263B293 P-2

Booster cylinder

ISO,150A

All

619C440 G-5

Box barrier assembly

250,250A

All

619C440 G-6

Box barrier assembly

All

258C614 P-13

Box barrier guide (right)

All

258CS14 P-36

Box barrier guide (left)

All

258C619 G-3

Arc chute clamp

All

258C614 P-4 & P-16

All

802B723 G-4

Vertical barrier front

All

281B708 G-2

Operating Rod

All

600/1200

258C614 P-6

Horizontal barrier, upper

All

2000

258C614 P-7

Horizontal barrier, upper

150A

600

265C188 G-1

Bushing (long)

ISO,150A

1200

269C842 G-1

Bushing (long)

250,250A

1200

269C842 G-1

Bushing (long)

3 of ea.

Arc chute support

All

2000

265C188 G-3

Bushing (long)

All

258C619 P-8

Connection bar

All

2S8C614 P-S

Block

All

600/1200

258C614 G-3

Horizontal barriers (lower)

All

2000

258C614 G-3

All

600/1200

All

•c

REQ.

MVA

NO.

AM 4.16-(MVA)-3

REF.

Horizontal barriers (lower)

258C614 P-20

Top Plate

2000

6592511 P-1

Top Plate

All

258C683 G-1

Wheel assembly complete

236C767 G-7

All

6597296 P-6

All

2000

6442246 P-1

Spacer

All

2000

6441630 P-1

Washer

All

2000

6442257 P-1

Bearing

All

2000

369A407 P-1

Spring

All

2000

6442258 P-1

Stud

All

6441617 P-l

Washer

All

600/1200

414A106 p.4

Screw

All

600/1200

421A239 P-1

' 31

All

600/1200

6442371 P-1

1 50A,250A

258C672 G-1

150, 250

281B726 G-1

Wheel Si spreader bushing

Spring
3

Bearing

Mechanism cover (interchangeable)
Mechanism cover (standard)

All

6597296 P-S

Front wheel and caster

All

236C792 P-2

Loose rings

Those breaker model list numbers with "W suffbc

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16

i53

rso 155

Tfrm.,,

iS-1

Fifli 281

Front View

Fij. 288

Fig. 28

r66

166 165 163 rSi iSl

18?

Ccaponent Farts

Fig. 28C

Rear Bushing Isseaibl)' (Ref. Ko. fSO)

PARTS REFEREKCED IN nOS. 28A. 28B L 28C

CAT. NO. FOR

AM-A,16-(MVA)-3
150A

ISO, 150A
2SO,2SOA
All
ISOA
All
AU

ISOA

ISO, ISOA
2S0, 2S0A
All
ISOA
All
AU
AU
AU
AU
AU
AU
AU
ISOA

ISO, ISOA
250, 250A
AU
ISOA

ISO, ISOA

2S0, 250A
AU

ISOA

ISO, ISOA
2S0,2S0A

236C790 G-l

236C790 G-2
2360790 G-3_.t
236C790 C-4
265C187 G-l
269C84I G-l .
265C187 G-3 .
6592330 P-2
6592330 P-2
6592331 P-2
6592331 P-2
236C79I P-9
236C791 P-9
236C791 P-19
236C79I G-3

239C791 G-l
236C791
236C790
414A116
6445087
414A180

G-4
G-9
P-4
P-2

414AI80

6509787
6S097B7

250, 2S0A
AU

ISOA

ISO, ISOA

250, 2S0A
AU
AU

250, 2S0A
ISOA

150, ISOA
2S0, 2S0A
AU
AU

Spring Retainer
Spring Retainer
Spring Retainer
Spring Retainer
Support
Support
Support

Arcing Contact Support
Flexible Connection
Flexible Connection

Arcing Contact Assembly
Insulating Plate
Buffer

Spring
Spring

^rlng Guide

236C790 P-22
Nar. Wash. 1/4-20
Nar. Wash. 1/4-20

Washer for ^ring Guide

Nar. Wash. 1/4-20
2SSC666 P-l
2S8CB66 P-l

ISO, ISOA

Rear Bushing (Short)
Rear Bushing (Short)
Rear Bushing (Short)

Spring Guide
Spring Guide

ISOA

All
ISOA

Rear Bushing, Assembly

Rear Bushing, Assembly
Rear Bushing, Assembly

236C790 P-22
236C790 P-22

Nar. Wash. 1/4-20

2S0, 2S0A

DESCRIPTION

236C790 P.22

AU
AU

ISO, ISOA

NO. PER
BREAKER

17SVS57 P-l

258C666 P-3
2S8C666 P-2
236C791 P-8 236C791 P-8- .
236C791 P-8
236C791 P-8~
2S8C666 P-5
2580666 P-S
236C791 P-20
236C791 P-3
238C791 P-4
2580666 P-4
6557243 P-l
6557243 P-l

6557243 P-2
6557243 P-l
26S0151 P-25

Spring Guide

Washer for Spring Guide
Washer for Spring Guide

Washer for ^ring Guide
Lock Plate

Contact Support
Contact Support
Contact Support

Contact Support
Contact Finger
ConBct Finger
Contact Finger
Contact Finger

Primary Contact
Primary Conuct
Primary Conttet
Primary Contact
Primary Contact
Spacer

Buffer
Buffer
Buffer
Buffer

Clamp
Clamp
Clamp
Clamp

Spring Baffle

Finger Reuiner
Finger Retainer
Finger Retainer
Finger Retainer
Finger Retainer

Sack Yiex

Magne-Blast Circuit Breaker T>-pe AM-4.16 GEH-2000

211

220213 212 213 212

220 211 213 212 213 212219 215 220 211

212 213 219

V'i

m
217

218

215

214

2I8A

217 I

215 219 221

218

219

218A

Fig. 29A

For 2000 Ans. Breakers,

Fig. 29B

All Ratings

for 1200 Ano..

29C

250 nva Rating

Fig. 29

For 600 and

150 nva Rating

Movable Contact Aris Asseobly

PARTS REFERENCED IN FIGS. 29A, 29B & 29C
CAT. NO. FOR

AM-4.16 (MVA)-3

NO. PER
BREAKER

DESCRIPTION

ISOA

236C792 G-5

ISO, 150A

Movable Contact Arm Assembly

236C792 G-5
236C792 G-7

Movable Contact Arm .Assembly
Movable Contact Arm Assembly
Movable Contact Arm Assembly

250, 250A
ALL
ALL

236C792 G-6 ^
802B742 G-3r^

ISOA

6591644 P-7

Movable Primary Contact

ISO, ISOA
250, 250A

6591644 P-7

Movable Primary Contact

6591644 P-7

ALL

6591644 P-7

150A

6591644
6591644
6591644
6591644
258C566

Movable
Movable
Movable
Movable

ISO, ISOA

250, 250A
ALL
ALL
ALL
ALL
ALL
ALL

ISOA

150,150A
250,2S0A
ALL
ALL
ALL

250, 250A

P-8
P-S
P-8
P-8. .
P-7

Movable Arcing Contact

Primary
Primary
Primary
Primary

Contact
Contact
Contact
Contact

Movable Primary Contact
Movable Primary Contact
Contact Arm

236C792 G-8

Tube & Piston Assembly

258C666 P-6
421A248 P-1

Contact Arm

456A874
4S6Aa74
456A874
456A874
456A874

Piston Ring Expander

P-3
P-2
P-2
P-2
P-2

414A146 P-4
414Ai46 P-3
258C619 P-2

Piston Ring
Piston
Piston
Piston
Piston

Ring
Ring
Ring
Ring

Flex Nut
Flex Nut

Spacer

Equalizer
Equalizer
Equalizer
Equalizer

1200 Abo.,

GEH-2000 Magne-Blast Circuit Breaker Type AM-4,16

326

328

%
329

VIEW AA
Fig. 30A

Early Design

Fig. SOB

Present Design

326

VIEW A
Fig. 30C

Fig. X

present Design

Interlock Plunger

PARTS REFERENCED IN FIGS. 30A, SOB & 30C FOR ALL RATINGS
CATALOG NO. FOR TYPE

REF.
NO.

AM-4.16-(MVA)-3

324
325
326
327
328
329
330
331
332

236C769 C-1
6442255 P-1
236C7S9 G-2
6509728

6477427 AA P-9
6443714

6477427 CA-PT-2
6597228 P-1
236C769 P-9

AM-4.16-(MVA)-3 0
236C787
236C787
236C787
6509728
383A926
236C787
236C787
236C787
236C787

G-1
P-12
G-2
AD P-1
P-14
P-5
P-16
P-6

NO. PER
MECHANISM
1
1
1
1
2
1
1
2
1

DESCRIPTION

Plunger interlock complete
Plunger for interlock
Bracket for interlock

Spring for interlock
Pin
Roller
Pin
Crank

Front guard

This plunger interiock frame is wider than the mechanism frame.

0 This plunger interiock frame is narrower than the mechanism frame.
26

^ Mm--

ff-irl

»»«??

J Vj

rig. 3U

R\qht Side View

519* SIB

fig. 31

front Vlei'

fig. SIC

Left Side View

HS-13 Hschanisra for Type JM-«-l6 Breaker

PARTS REFERENCED IN FIGS. 3IA, 31B & 3iC FOR ALL RATINGS

REF. NO.

CAT. NO. TYPE

AM-4.16-(MVAl-3

2S8C604
258C604
236C795
174V394
644S0S9
41SA489
2S8CS09
4S6A876

G-3
P-2
P-40
P-1
G-I
P-4
P-4

236C788
414A190
236C788
258C601
258C601

P-6
P-3
G-3
P-14

236C788
236C788
258C60I
236C788
456A866
4S6A866
6174582
6174582

P-8
P-7
P-16
P-30
P-1
P-1
G-1
C-2

6174582 C-U

6275070 G-1
6275070 G-2
21SD470G-5

Not shown

NO. PER
MECHANISM

DESCRIPTION

Manual trip rod

Manual trip rod support
Rod for control device
Tube

bisulating tube
Auxiliary switch
Crank

Spacer
Interlock prop shaft
Spring
Interlock prop

Bearing bracket
Shaft
Link
Crank
Crank
Bracket

Latch checking switch
Interlock switch

Potential trip coil (12Sv d-e)

Potential trip coil (250v d-c)

Potential trip coll (230v a-c>
Potential trip coil ( 24v d-c)

Potential trip coll ! 48v d-cj
Potential trip linkage

GEH-2000 Magne-Blast Circuit Breaker Type AM-4.16
PARTS REFERENCED IN FIGS. 32A, 32B L 32C FOR ALL RATINGS

REF.
NO.

CAT. NO. FOR

NO. PER
MECHANISM

DESCRIPTION

AM-4.16-(MVA)-3
250
251
252
253
254
255
256
257
258
259
260
261
261
261
261
262
263
263A
263A
264
264
264A
264A
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
.283
'284'
286
287
288
.289

P-2
P-6
P-7
G-54
G-55

Spring

2S8C604
6192382
215D470
281B711
258C609
6375521
6375521
6375521

P-8
AB P-1
G-51
G-1
P-1
G-2
G-6
G-1

6375521
236C796
6591632
6591632
6591632
236C795
236C795
236C796
236C796
414A109
236C796
236C796
383A926
258C630
258C630
258C630
414A109
258C630
369A411

G-5
P-6
P-1
P-1
P-2
P-4
P-45
P-14
P-12
P-4
G-2
P-8
AE P-1
P-7
G-3
P-8
P-8
G-1

369A468
258C630 P-3
258C630 P-5
258C630 P-4
258C630 P-9
258C611 P-1
258C611 P-11

Closing coil (125v d-c) 250 mva
Closing coil il25v d-c) 150 mva
Closing coil (250v d-c) 250 mva

Closing coil (250v d-c) 150 mva
Plunger (AM-4.16-150/250)
Piston Ring (AM-4.16-150 & 250)

Piston Ring {AM-4.16-250)

Piston Ring (AM-4,16-150)
Pole piece (AM-4.16-250)

Pole piece (AM-4.16-150)
Guide for pole piece (AM-4.16-150)
Guide for pole piece (AM-4.16-250)
Washer

Arm plate
Stud
Pin
Clevis
Plate
Rod
Buffer

Complete spring assembly
Inner spring
Outer spring
Spring retainer
Retaining plate
Pin
Bracket

CTrip shaft bearing
Latch shaft

421A256 P-1
215D470 G-53''215D470 G-52

258C611 P-3
^
, 414Ati4-P-l "W*"6''
IA256.E-1

Link

Indicator assembly
Prop

Stop bar

-1 UtATHC

215D470 P-18
6509799
414A110 P-3
6477097
2S8C609 P-8

luring clip
Veedcr counter

Spring base

383A926 AF P-20

291
292

299
301
302
303
304
305
306
307
308
308

Shaft
Crank
Latch
Crank
Link

6551742

"290293
294
295
296

6443518
2S8C608
258C608
2150470
21SD470

104A2474 P-1

421A201 P-1
2S8C608 P-3
258C611 P-5

^ring

Roller Link

Prop pin
Trip roller pin

Trip roller bearing
Spacer

^ring
Pin

Prop spring
Pin
Pin

Spacer
latch guide
Pin

258C609 P-9

421A209
2S8C609
383A926
421A208
619C478
619C478

Spacer

P-101P-6
AE P-39
P-143
P-20
P-19

Roller
Pin

Spacer

Pin for center pole
Pin for end pole

Magne-Blast Circuit Breaker Type AM-4.16

GEH-2000

306.

I SEE VIEW C)

• I

256

(SEE VlEWAl

268

25r

(SEE VIEW B)
(SEE VIEW C)

(SEE VIEW 0)
254

(SEE VIEWE)
264-

.261

263

.262

€>

-263

y/////A

?r77Z>>7^/P-7777'tnr

i?
Fig. 32A

Cross-sectic

Fig. 32B

Complete Spring Assembly
{fief. No. 273)

301.,

302

293

283 Ii284

252

283

-299

281

292

VIEW D

VIEW A

253

258

306-

303 - ,

ii 304 ^— 305 ij

T
i c

VIEW E

VIEW G

VIEW e

Ccrf>/A/

n
294-

253J

296

BlliBM

307.

295
307

u
VIEW C

VIEW F

Fig. 32C

Fig. 32

Detailed Views

HS-13 Mechanism for AM-e.ls-3

GEH-2000 Magne-Blast Circuit BreaJter Type AM-4.16

Fig. 33 Seconder]' Dieconnecting Device
(Ref. 600)

Fig. 3V

Maintenance-Closing Device

(Ref. 610)

PAflTS REFERENCED IN FIGS. 33 & 34 FOR ALL RATINGS
CAT. NO. FOR TYPE

AM-4.16.(MVA)-3

NO. PER
MECHANISM

802B795 G-3
264B173

G-2

DESCRIPTION

Secondary disconnect device, complete; 16 point
Secondary disconnect device, complete: 7 point

6319964

P-2

34S768

p.j

Lock washer for plug

6505244

P-1

Socket

258C569 G-1

3663094

P-38

366A234 P-1
366A234 P-2

Additional drilling In field - 121AS912.

Plug

Maintenance closing device
Spacer
Contact nut
Contact nut

Magne-Blast Circuit Breaker Type AM-4.16

Fig. 35

Pertlel Vie* of hS-13 Heainisa .ith C»irrmt Trip

Fig. 36

Undervoltage Ceviee (Ref. 647}

PARTS REFERENCED IN FIGS. 35 & 36 FOR ALL RATTOGS

CAT. NO. FOR TYPE

AM-4.16-(MVA)-3

NO. PER
MECHANISM

DESCRIPTION

6551725

366A611 C-1
6558748
6558756

6477418
366A600
6076401
6477427
OOifeW"

P-1
P-i

AA P-10
P-1
p.307
AA P-8
AA ".1 SXtJT ^ I

n5V574
369A443

6551726
175V578

8076401 P-309
6076401 P-305

295B227 G-2
175V576
374A246 P-1
175VS62 P-1
384A330 G-1

Bracket

Trip latch
Ball bearing
Trip arm
Pin
Pin

Undervoltage device complete

^op for d-c only
^rlng for d-c only
Spring for a-c only
Pin for d-c only
Pin for a-c only
Pin

Switch
Pin
Bracket

Shim for d-c only
Link arm assembly for d-c only

8477414 AC P-20
6558711 P-1
6558723 G-1

Stud

6509798

Spring

6275017 G-19
6275017 G-33

6275017 G-20
684C642 G-1
•?
Not Shown

Trip pan

Coupling
Trip arm

Coil (l25v d-c)
Coll (230v a-c)
Coil (250v d-c)
Terminal board (6 point)

C3. !_ {4&VIX

GEH-2000

GEH-2000 Magne-BUBt Circuit Breaker TVpe AM-4.i6

Fig. 37 Imoacl Trio Device (Ref. No. 702)

PARTS REFERENCED IN FIG. 37 FOR ALL RATINGS
CAT. NO. FOR TYPE
AM-4.16-(MVA)-3
6594553 AA

6591817 P-1

6591388 P-19

6076403 P-315
6477425 BA P-3

Impact trip device complete
Lever

Locking plate
Pin
Roller
Pin

6076403 P-311
6592554 G-l

Crank

6557106 P-1
6558791 G-l
8509706
6443516

Spring

8557105 P-1
65S8746 P-1
8558747 P-1

Adjusting screw

Eyebolt asm.
Bracket
Spacer
Bracket
Trip arm
Pin

6076401 P-315
6477401 AA P-3

Spacer
Spring

6509794
n4V378
174V373

Rod

Coupling

6443666

2953227 G-3
6592505 AA
6558752 G-l

8558751 P-1
6049320

6557068

P-9

6076401

P-385

2236575

4905058

G-4

6443667

6174599

G-2

6174599

G-6

456A334 P-1
« Not shown

description

NO. PER

MECHANISM

Bracket
Switch

Frame assembly
Core assembly
Angle
Felt washer
Pin
Pin

Guide
CoU frame

Bracket

Coll for current trip 3 A^. a-c
Cotl for capacitor trip 230v a-c

Rubber guard

Magne-Blast Circuit Breaker Type AM-4.16 G£H«2000

1^4
im.
•
'
• rs'''

Fig. 38

Control Device (Re'. Ho. 750)

PAHTS REFERENCED IN FIG. 38 FOR ALL RATINGS
CAT. NO. FOR TYPE

AM-4.16-(MVA)-3
403A225 G-1
403A224 G-4

DESCRIPTION

Control device, 125 volt, d-c

Control device, 230 volt, a-c (continuous)

6375988 G-$

Control device, 250 volt, d-c

403A224 G-3

Control device, 230 volt, a-c

•l-ir-W»B227 G-2
295B227 G-I

6275017 G-I9

6275017 0-33
6273017 G-20
6275017 G-34
6591455 P-l
6442392 P-l
6591411 G-l

6591450
64I22SS
6412251
6591440

P-l
P-l
P-l
0-1

6592161 P-l
6592162 P-l
6477041 P-I

6591412 G-l
6591404 G-l

6272844
36SA4S8

6370699
6477063

456A812 G-l

Not shown

NO. PER
MECHANISM

Auxiliary switch, lop or back
Auxiliary switch, top, 230 volt, a-c only

Coil, 125 volt, d-c

Coil, 230 volt, a-c (continuous)
Coil, 250 volt, d-c

Coil, 230 volt, a-c (intermittent)

Support for contact tip
Insulation

Support for stationary contact
Core

Blowout coll

Support for coil
Connector

Support for movable contact
Shield

Spring
Movabie contact

Arc chute assembly
Spring

Spring (a-c intermittent and d-c)
Spring (a-c continuous)
Spring

Hardware for mounting control device

· INSTRUCTIONS
AND
RENEWAL PARTS

GEH-2054C

SUPERSEDES

GEH-20548

l)/J I I

MAGNE -BLAST CIRCUIT BREAKERS
AM
AM
AM
AM
AM

Types

4.16-1SOA-4and-4S
4.16 -250A • 4and-4S
4.16-150H-4and-4Ml
4.16-lSOH-45 and -45 ML
4 .16. 25 -4 and -4ML
- 45 and -45 ML
4.16-2
with
Operating Mechanisms
ML-11 and M5-13
CONTINTS
INTRODUCTION •••••. • . .•. • 3
HANDLING
,RECEIVlNG,
'
AND STORAGE • •. ••. .••.. 3
INSTALLATION •••.•.•.• , •. 3
4
DESCRIPTION OF OPERATION
ADJUSTMENTS ••••••• , •• , • 6
INSPECTION AND TEST •..••• 10
MAINTENANCE •••.•••.•••. 12
RENEWAL PARTS •..•••..•• 23
PARTS RECOMMENDED FOR
NORMAL MAINTENANCE .••. 23

MEDIUM VOLTAGE SWITCHGEAR DEPARTMENT

GENERAL. ELECTRIC
PHILAltELPHIA, P A.

£n-20S4 Magne-falast CircuitBreaker Type AM-4.16-4

1. Secondary Coupler
2. Auxiliary Svitch
3. Poaition Indicator

4. Opening Spring Unit
5. Operation Counter
6. Manual Trip
7. O^ntrol Device

S. Gontrol Device Plunger Guide
9. Cloting Solenoid

10. Plunger Interiodc (Optional)

Flo. I

HS-13 Operatino Kechanisa

1. Closing Araature

2. Maintenance Operating Device

3. Handle

4. Release Valve

Fig. 2 Method of Mounting Maintenance Operating Device

MAGNE-BLAST
TYPE

CIRCUIT
TYPE

4.16-1S0A-4

BREAKERS

AM 4.16-150H-4 AND

-4ML

) TYPE

TYPE

4.16-250A-4

4.16-2S0H-4 AND

INSTRUCTION BOOK GEI-50143 SUPPLEMENTS THIS BOOK FOR BREAKERS WITH ML-11 STORED

ENERGY OPERATING MECHANISM (INDICATED BY ML SUBSCRIPT IN TYPE DESIGNATION).

INTRODUCTION
The magne-blast circuit breaker Is the
removable Interrupting element for use In
vertlcal-lUt metal-clad swltchgear, topro
vide reliable controlandprotecHonofpower

erates on the principle that
arc can be
interriq>ted In air by sufficiently elongating
and cooling It. This Is accomplished by
means of a strong magnetic field that
lengthens the arc and forces itinto Intimate

metal-clad switchgear are added protection
to equipment and personnel, compactness,
simplified Installation and reduced main
tenance. In keeping with these features the

contact with cool dielectric materiaL

systems. Among the many advantage of

magne-blast breakers are designed for Interchangeablllty and manueverablllty, to
gether Witt reliability and low maintenance
requirements.
The magne-blast circuit breaker op

The AM-4.16 magne-blast breaker is
available in a number of currentand voltage
ratinra. Refer to the breaker nameplate
for the complete rating information of any
particular breaker. The short circuit con
ditions to be Imposed on the breaker must
not exceed Its rating, nor should It be called
upon to operate at voltages or currents

greater than those given on the nameplate.
Since this book Is written to cover several

ratings of breakers that are of the same
general design, all Instructions will be of a
general character and all Illustrations will
be typical, unless otherwise specified.
PROPER INSTALLATION AND BdAlNTENANCE ARE NECESSARY TO INSURE
CONTINUED SATISFACTORY OPERATION

OF THE BREAKER. The following In
structions will provide complete informa
tion for placing the magne-blast breaker In
service and for maintaining satisfactory
operation.

RECEIVING, HANDLING AND STORAGE
RECEIVING AND HANDLING

all parts against the packing list to be sure
that no parts have been overlooked.

Each breaker is carefully inspected
and packed by workmen experienced In the
equipment

Immediately upon receipt of

the circuit breaker, an examination should

Injury or rough handling Is evident a
image claim should be filed immediately

with the transportation company and the

nearest General Electric Sales OHice should
be notified.

It Is expected that due care will be

exercised during the unpackingand installa

tion of the breaker so that no damage will
occur from careless or rough handling, or
from exposure to moisture or dirt Check

location, free from corrosive ^es or

fumes; particular care should be taken
STORAGE

proper handling and packing of electrical

—^e made for anydamage sustained Intransit

2. The breaker should be stored In a clean

It is recommended that the breaker be

put Into service Immediately In Its per
manent location. If this Is not possible,
the following precautions must be taken to
insure the proper storage of the breaker:
The breaker should be carefully pro
tected against condensation, preferably
by storing It in a warm dry room.
Circuit breakers for outdoor metal-clad

switchgear should be stored In the equip
ment only when power Is available and
the heaters are In operation to prevent
condensation.

to protect the equipment from moisture
and cement dust, as this combination
has a very corrosive effect on many
parts.

3. Machined parts of the operating mecha
nism, etc., should be coated with a heavy
oil or grease to prevent rusting.

If the breaker is stored for any length

of time, it should be inspected periodically
to see that rusting has not started and to
insure good mechanical condlUoo. Should
the breaker be stored under unfavorable

atmospheric conditions, steps should be
taken to dry out the breaker before It Is
placed in service.

INSTALLATION
Remove box barrier and mechanism

covers and make a visual inspection to
ascertain that the breaker Is in satisfactory
condition. Check all bearingsurfaces of the
mechanism for lubrication.

Refer to the

section on LUBRICATION (page 12).

Operate breaker manually using the
maintenance closing device provided with

the breaker. Duringthe closing operation,

trically until It has l>een iterated manually

cover and replace box barrier.

The following adjustments should be
checked at this point.

If breaker has been stored for a long
period of time, it is recommended that the

a. Primary contact wipe (page 6).

cycle hl^ potentialtest—see INSOLATION
TEST (page 12).

Insulation be checked with the standard 60

b. Primary contact gap Cpsge 6).
c. Prop clearance (page 9).

check to Insure tlmt the mechanism and

breaker does not stick or bind during the

entire stroke, that It latches secure^ In
the closed position, and that it trips freely

when the manual trip plunger Is (qierated.
The breaker should not tie operated elec

Remove test coupler, attach mechanism

to Insure this freedom of action.

Attach test cove except thatarelay mountedelsewhere

rangement of the control device.

from the booster tube (28) and

forces the arc onto the lower arc rtinner

An arc forms as the

arc into a gradually deepening serpentine
path, so that the electrical resistance in

the path of the arc is rapidly Increased
and the heat from the arc is absorbed. The

increased resistance reduces l>oth the mag

nitude and the phase angle of the current,
and at an early current-zero the arc path
is so long and the gases produced by the
arc

cooled

that the arc

cannot re

establish itself, and interruption occurs.

GEH-20S4

Magne-blast Circuit Breaker Type AM-4.16-4

Prleary Contact Wipe

Arcing Contact Wipe

!• Stationary Primary Contacts
2. Uovabie Primary Contacts

5. Movable Arcing Contacts
6. Upper Arc Runner

3. Buffer Biock

7. Contact Arm

4. Stationary Arcing Contacts

Fig. 7

The 150 MVA interrupter is essentially
the same as the 250 MVAinterrupter except

Contact Adjustments

trip circuit, the manual trip (6), Fig. 1, is
used.

that it utilizes the magnetic elements in the
upper runner only.
TRIP FREE OPERATION

lanual tripping follows the same pro.re except that instead of energizing the

If the trip coil circuit is energized
while the breaker is closing, the trip plunger

will force the trip latch (2), Fig. 5, away
from the trip roller (3) causing the mecha
nism linkage to collapse and the breaker to
re-open. The closing armature (6) com
pletes its closing stroke, but the closing
coil is de-energized at the endof the stroke,
and the armature is returned to its original
position by gravity.

ADJUSTMENTS
DO NOT WORK ON EITHER THE
BREAKER OR THE MECHANISM WHILE
IN THE CLOSED POSITION UNLESS THE
PROP AND TRIP LATCH HAVE BEEN
SECURELY WIRED OR BLOCKED TO PRE
VENT ACCIDENTAL TRIPPING.

A maintenance operating device is
provided for (deration of the breaker during
adjustment checks. Mount the device as
shown in Fig. 2, and turn the release valve

(4) firmly to the right. To close the breaker,
operate the handle (3) with a pumping mo
tion. By turning the release valve (4) to
the left, the closing armature will return
to its normal position. Electrical operation
must not be attempted until the breaker

has been operated manually through its
complete stroke several times and final

Installation inspection has been completei
Interlock Sal

7. fiounilng Scr<

S. Mounting Sere

Fig. 10

Interlock Switch an

Front Dijconnect Stud

Plunger Interlock Boll
Waxheri

Connecting Rod
Reset Plate

Reset Roller

Main Operating 9iafc
Reset Aro

Trip Plate
. Spring
. Trip Bole
. Clevis

, Elevating Bar

. IiQpacC Trip Plate
. Trip Latch

. Trip Roller
. Trip Amature
. Trip Lever

. Undervoltage Trip KaoDer
. Adjusting Rod
. Manual Trip Button

. Trip Setting Plate
. Undervoltage Device

Magne-blast Circuit Breaker Type AM-4.16-4
PROP CLEARANCE

toward the

Refer to Fig. 9. With the breaker closed

as far as possible with the n»intenance

device, the clearance between the closing
pin -(10) and the prop (15) should be 1/32"
to 3/32", Measure the prop clearance with
a feeler gauge to determine whether or not

an adjustment should be made, and if so,

Using a small drill, spot the closingplunger
through the set screw hole. Replace the

set screws.

To remount the armature on

the breaker, compress the piston ring (18).

MANUALLY

After reassembly, remount the maintenance

closing device and check the adjustment.

CLOSING PLUNGER CLEARANCE

(AM-4.16-150A-4, 2S0A-4)

Refer to Fig. 6. The lever arm (5)
is set at the factory and will require no
adjustment. With the breaker in the open
position, depress the arm of the cut-off

switch (1). There should be 1/32" to 1/16"
clearance between the depressed roller
of the switch and the striker (3). Washers

3. Locking Bolts
4. Pin
5. Link
6. Rod

AUXILIARY DEVICES

Latch Checking Switch Adjustment

the closing plunger (17) and the
roller (14) should be 1/16" to
To obtain this clearance, the nuts
the two armature guide bolts (23)

Shalt (4) manually clockwise to release

Both nuts should be

moved the same amount.

After making

an adjustment, close and open the breaker
y^^^and recheck the plunger clearance. Re-

Seat the adjustment if necesssary.

INTERLOCK SWITCH ADJUSTMENT

Referring to Fig. 10, rotate the inter
lock shaft (1) manually clockwise to release

the interlock switch arm (S). The point
at which the contacts make can be de

termined with a circuit continuity tester
such as a light indicator or beil set.
To obtain adjustment on the interlockswitch

(6), bend the interlock switch arm (5).
The roller and crank on the interlock

switch (6) should have 1/32" to 1/16"

Referring to Fig. 10, rotate the trip

the latch checking switch arm (2).

determined with a circuit continuity tester

pin at either end of the adjusting rod
assembly (20), and turning the clevis at

such as a light indicator or bell set. To

that end.

obtain adjustment on the latch checking
switch (3), bend the latch checking switch
arm (2). The roller and crank on the latch

checking switch (3) should have l/32" to
1/16" overtravel after final adjustment.
Impact Trip. Current Trip and Undervoltaee

Fig. 12 shows the necesssary settings

depress the plunger (4) on the top aux

iliary switch (3). The gap between the
plunger and operating arm should be 1/32"

or greater.

To Increase the overtravel,

loosen the screws (2) and move the switch

(AM-4.16-1S0-4 and 250-4)

should be 3/32" to 5/32".

Refer to Fig. 12. With the breaker
in the open position, the vertical distance
"A" from the top of the interlock bolt

This can be

altered by changing the number of shims

under the block against which the trip

can be altered by releasing the check nut
and screwing the trip bolt (11) in or out of
the reset arm (8).

For ease in reviewing the adjustments

a. Primary contact wipe (Fig. 7):

5/16" + 0 - 1/16".

® '

b. Arcing contact wipe (Fig. 7: 5/16"
or greater (gap at primary contacts).

(2) to the bottom of the elevating bar (13)
should be 15-19/32" ^ 1/16". To change
this adjustment add or remove washers (3).

Auxiliary Switch Linkage

(Furnished Special on AM 4.16-1S0A-4
and 250A-4)
Refer to Fig. 13.

When an undervoltage device is fur

nished check the clearance between the

With the breaker

in the open position, the distance from
the center line of the front bushings (1)

to the center of the slot in the fork lever

trip hammer (19) and the trip plate (14), (2) should be 12-9/32" as shown. To
with the undervoltage coil energized. This change this setting, loosen the locking
clearance should be 1/32" to 1/16" and bolts (3) and move the fork lever in the
can be altered by removing the connecting proper directian. Tighten the lock bolts.

INSPECTION
the following are recapitulated:

Plunger Interlock

that are to be checked when these devices

are furnished. The amount of wipe between
the trip roller (16) and the trip latch (15)

In order to trip properly, the clearance
between the trip bolt (11) and the trip
plate (9) should be 1/32" to 1/16". This

device by pressing the operating arm (5)

After checking all the mechanical ad

justments as outlined above, operate the
devices manually to make certain that they
trip and reset properly.

Trip Devices

CONTROL DEVICE ADJUSTMENT

With the device in this position further

Auxiliary Switch Linkage

The

plate (14) stops.

)with full extent of travel to the rear.

Fig. 13

point at which the contacts make can be

overtravel after final adjustment

Referring to Fig. 11, measure the
overtravel of the two auxiliary switch
plungers. Manually operate the control

2. Fork Lever

to correct adjustment.

raised or lowered.

1. Front Buihing

(4) should be added or removed if necessary

Refer to Fig. 9. With the breaker in
the open position, the clearance between

CUT-OFF SWITCH ADJUSTMENTS

closing
3/16".
(22) on
may be

OPERATING

ATION.

quired adjustment, then replace the closing

BEFORE

COIL AND PRODUCE A CLOSING OPER

plunger, screwing it down against the shims.

THE CONTROL DEVICE, MAKE CERTAIN

Lower the armature from the mechanism

thickness of shims (20) to give the re

travel on the back auxiliary switch (1).

careful not to drop the armature (21).

and remove the two set screws (19). Re
move the closing plunger (17) from the
armature and add or subtract the necessary

In a similar manner, check the over-

first be necessary to open the breaker

To make the adjustment, it will

and remove the maintenance operating de
vice. Remove the stop nuts (22and 24) being

—

rear of the mounting plate.

Tighten the screws and recheck the ad
justment.

THAT ALL CONTROL POWER TO THE
BREAKER HAS BEEN DISCONNECTED.
MANUAL OPERATION OF THE CONTROL
DEVICE WITH CONTROL POWER CON
NECTED WILL ENERGIZE THE CLOSING

exactly how much adjustment will be re

quired.

GEH-2054

AND

TEST

c. Primary contact gap (Fig. 8):
3-13/16" + 1/8" - 3/16".
d. Trip latch wipe (Fig. 9):

3/16" to 1/4" with trip latchresting

against stop pin.

e. Prop clearance (Fig. 9):
1/16" + 1/32".

Closing plunger clearance (Fig. 9):

1/16" to 3/16".
Interlock switch overtravel (Fig. 10):
1/32" to 1/16".
Control device switch overtravel

(Fig. 11); 1/32" min.
Cut-off switch overtravel (Fig. 6):
1/32" to 1/16".

GEH-2054

Magne-blast Circuit Breaker T^e AM-4.16-4

RECTIFIER REFERENCE CHART
Rectifier Resistor Setting

Closing Coll

Dwg. No.

Amps.

637552IG-6

58.0

Gezmanlum

Silicon

1.50^
to

637552IG-2

1.2552

62.0

I ''

' I

95.0

1.0^ ea. bridge}

0.75S1

115.0

iJL_l

f''

' 1

Resistor Taps

isi]§n\§si]ia

Fig. m
f

Laich checkinR switch overtravel

(Fig. 10): 1/16" to 1/32",

The capacitor trip should be capable
tripping the breaker as late as 25

k. Impact trii roller wipe (Fig. 12):

seconds after the control voltage is re
moved.
If the auxiUary devices do not

I. Impact trip bolt clearance (Fig. 12):
3/64" + 1/64".

be made for defective parts.

l/iF+ 1/3S

perform in accordance with these spec
ifications

n. Plunger Interlock (lSO-4 and2S0-4)

(Fig. 12): 15-19/32" + 1/16".
0. Auxiliary switch linkage (150A-4
and 2S0A-4) (Fig. 13): 12-9/32".
AUXILIARY DBVICBS

On breakers that are equipped with
auxiliary devices such as a current trip,
undervoltage trip,

the device should be

checked for proper electrical operation.
The current trip device should trip the
breaker at 3 amperes. The undervoltage
trip device should trip the breaker'idien the

control voltage drops below 30 to 60% of
rated voltage, and it should pick iq> at

80% of the control voltage or less. An

adjustment plate is provided on the front
of the undervoltage trip device as an aid

careful

examination

should

OPENING AND CLOSING SPEED

m. Undervoltage trip hammer clear

ance (Fig. 12): 2/64" + 1/64".

The closing speed of the arcing con
tact should be 7 to 10 feet per second
for

the ISO MVA breakers and 9

to 12

feet per second for the 250 MVA breakers
with rated closed circuit voltage at the
closing coil terminals.
These speeds

represent the average speed of the mov
able arcing contact from a point 1" be
fore the tv is tangent to the lower surface

equal to 80% of normal control voltage

/^^il as it will overheat the coil, produc-

\
a false reading, and may damage
.e coil if excessive overheating occurs.

NOMINAL
VOLTAGE

CLOSING
RANGE

TRIPPING
RANGE

12Sv d-c
250v d-c
230v a-c

90-130V d-c
180-260V d-c
190-250V a-c

70-140V d-c
140-280V d-c
190-250V a-c

NOTE:

When repetitive operating is re

quired from a direct current source, the
closed circuit voltage at the closing coil
should not exceed llSv d-c and 230v d-c

at the nominal voltages of 125 v d-c and
2S0v d-c, respectively.
To check the d-c voltage at the closing
coil terminals, proceed as follows:

The ppenlng speed of the arcing con
tact should be 12 to 18 feet per second
at rated control voltage.
This speed
represents the average speed over 3"
from the point when the tip on the movable
arcing contact is tangent to the lower
surface of the upper runner.

1. Mechanism with a control device. Fig.
4.
Close the breaker \S3 manually
Iterating the control device.
Hold
the contacts in the closed position and
read the d-c voltage at the closing
coll terminals.
To de-energize the
circuit, release the control device.

CONTROL POWER CHECK
After

to the undervoltage device coU. The de
vice should pick up at this value.
Do
_not increase the voltage gradually on this

the breaker nameplate. Ordinarily, stand

ard ranges apply which are as follows:

of the upper arc runner to the tangent
position.

in obtaining the desired setting.
NOTE: When checking the pick-iq> value
of the undervoltage device, apply a voltage

closing and tripping voltages are given on

the

breaker

has been closed

and opened slowly several times with the
maintenance closing device, and the mech
anism adjustments checked as described
above, the operating voltages should be
checked at the closing coil and trip coil
terminals.
For electrical operation of
the breaker, the control power may be
either an alternating or direct current
source.
The operating ranges for the

2. Mechanism with cut-oH switch. Fig. 6.
Close the breaker by manually oper
ating the control relay located in the
metal-clad unit. Hold the relay closed
and read the d-c voltage at the closing
coil terminals.
Release the closing
relay to de-energize the circuit.
If the closed circuit voltage at the
terminals of the closing coil does not
fall in the specified range proceed as
follows:

Magne-blast Circuit Breaker Type AM-4.16-4

For D-c Operation

Resistor Setting For
•A-c Volts

Check voitage at the source of power
and line drop between the power source
and breaker.

Each Resistor

(Closed Circuit)

Summer

For A-c Operation (Fig. 14)

they are mounted in the metal-clad
unit. A tapped 1-1/2 ohms resistor
is provided in each rectifier circuit
to control the d-c voltage.

The re

sistor setting should be adjusted so that

224-236
234-246
244-260

0
0

1/2

1/2
3/4

214-226

1. When copper-oxide rectifiers are used

Winter

1/4

190-196
194-206
204-216
1

1-1/4

1/4
1/4
1/2
3/4
1

closing coil terminals is 110 to 120
Where repetitive operation

is required, the voltage should be set
at 105 4o 11a volts d-c.

2. When a germanium (coior-black, flanged base) - or a silicon (colorblue, hex base) - rectifier bridge as
sembly is used, it is mounted in the
metal-ciad unit.

The tabulation is included as a guide

for a^ttsting the resistors for the par
ticular combination of ambienttemperature

and a-e supply voltage.

Summer settings

are used where ambient temperatures are

normally above freezing (32''F).

It is

necessary to use winter settings where the
amhient temperature may drop to 20OF or
less at any time.
For a more detailed
explanation of copper-oxide rectifiers for
circuit breaker application, refer to in
struction book GBI-11306.

THE TIME REQUIRED TO CLtSSE THE

BREAKER.

(20 cycles max. at normal

voltage.) Both the coils and the germanium
and silicon rectifiers are designed for
Intermittent operation and may be damaged

by prolonged current How.

When two or more breakers, oper
ating from the same control power source,
are required to close simultaneously, the
closed circuit voltage at the closing coil
of each breaker must fall within the spec
ified limits.

A-c volts as measured across the rec
tifier and a-c series resistor.

the closed circuit voltage at the breaker
volts d-c.

GEH-20S4

These rectifiers are

of the button-type and are hermetically

Electrical closing or opening is ac
complished by merely energizing the clos

ing or trip coil circuit. Control switches
are provided for this purpose on the metal-

clad unit. It is also possible to trip the
breaker manually by pressing the manu^
trip button (6), Fig. 1. Before the brewer
is raised into position in the metal-clad
unit, rub a small amount of G.E. Contact

Lubricant D50H47 on the silvered portion
of the breaker studs to form a thin coating

sealed units.
They have been tested
and the associated resistor properly
set at the factory. Unlike copper-oxide
rectifiers the output of the germanium
or silicon unit is affected very little by

for contacting purposes.

ambient temperature changes and it
should not be necessary to disturb

bination is designed only for electrical

the factory setting.

NOTE:

This breaker mechanism com

closing when in use.

NEVER ATTEMPT

MANUAL CLOSING WITH THE BREAKER

IN SERVICE, for under such conditions,
DO NOT MAINTAIN VOLTAGE ON
THE CLOSING COIL ANY LONGER THAN

sufficient closing force and speed cannot
be applied.

MAINTENANCE
V

Dependable service and safer power
equipment are contingent upon the unfailing
Mrformaaee of the power circuit breaker.
To maintain such service, it is recom
mended that a definite inspection andmaintenance schedule be set up and followed,
as serious shutdowns can often be avoided

by locating potential sources of trouble in

an early stage.

A periodic lubricaUon of

parts subject to wear is also vitally im
portant for the successful operation of
the breaker.

BEFORE ANY MAINTENANCE WORK

IS PERFORMED, MAKE CERTAIN THAT
ALL CONTROL CIRCUITS ARE OPENED

^D THAT THE BREAKER IS REMOVED
"®tal-clad unit.

not WOM ON THE BREAKER ORMECHANIMIWHILE in the CLOSED POSITION

OOT^SS TK PROP AND TRIP LATCH
g^XSmS^NN
WIRED OR
BLOHBD TO SECURELY
PREVENT ACCIDENTAL
TRIPPING.

PERIODIC INSPECTION

^e frequency of periodic inspection

wwUM M dotomtzied by 6ftch operating
compMy on the basis of the nund)er of

OMi^ons (including switching), the mag-

cw'fentswhich
Interrupted,
and time
any
rausual operations
occur from

points to be included in an inspection,
and a number of general recommendations.

REPAIR AND REPLACEMENT.
Arc Chutes

hwtallations where a combina-

rocomitered, an inspection is recsevere fault operation.

Tue foUowtng instructions list the main

It the

contacts are burned or pitted, they should
be made smooth with Itoe file.

It is not necessary to inspect the arc

chutes unless there is evidence of diamage

or If the arc chutes are removed for any
reason. When Inspecting an arc chute, it
should be disassembled and the following

After completing inspection of the con
tacts, check the contact adjustments as
specified under INSTALLATION, ADJUST
MENTS.

points noted:
1. Scale formed over the surface of the
arc chute must not be removed, but

loose particles collected in the chute
should be blown out.

2. Cracks which have formed in the fins

of the arc chute are to be expected in

ceramic materials of this t^e when
subjected to the severe heat of an arc.

Mechanism

A careful inspection should be made
to check for loose nuts or bolts and broken

retaining rings. All cam, roller and latch
surfaces should be inspected for any evid
ence of damage or excessive wear. Lubri

cate the meclmism as outlined below, then,
using the maintenance operating device,

These fine cracks do not interfere with

open and close the breaker several times

the operation of the device in any way
and should be disregarded. Small broken

ates freely throughout its entire stroke.

to make certain that the mechanism oper

corners on the exhaust end of the chute

Check the mechanism aiQustments asspecUied under INSTALLATION, ADJUST

and should be disregarded.

MENTS. Check all terminal connections.

will not interfere with its performance

3. If the arc chute has suffered mechanical

injury due to dropping or accidental
striking, resulting in the actual break
ing off of fins, replacement of the chute

will be necessary.

OP®'attag experience will soon
* maintenance schedule which
W^ve auuruce
of proper breaker con-

can be inspected only after removing the
arc chute assembly, as explained muter

Breaker Contacts

By removing the box barrier the mov

able and stationary primary contacts and
the movable arcing contacts can be in

spected.

The stationary arcing contacts

Bushings and Insulation

The surface of the bushings should be
kept clean and unmarred. If the insulation

surface should become damaged, it should
be sanded, cleaned and refinished.
All other insulation parts on the break
er should be kept clean and dry. Smoke or

dust collected between inspection period

should be wiped off, and if dampness is
apparent, heaters should be installed to
insure dryness.

GEH-20S4

Magne-blast Circuit Breaker Type AM-4.16-4

ton Test

.•hen insulation has been repaired or

replaced or when the breaker has been

stored under adverse conditions, it is
recommended that the Insulation be checked
before the breaker is placed in service.

A standard 60 cycle high potential test

at 14,000 volts RMS will normally Indicate
whether the breaker is satisfactory for
service. With the breaker contacts in the

fully opened position apply the high po
tential

to each terminal of the breaker

individually for one minute with all other
terminals and the breaker frame grounded.

After high potential tests are made on

Lubrication at

Part

Ground surlacea such as

cams, rollers, latches, etc.

(Requires Dtaassembly)
Wipe clean and apply DSOHIS.

Very light aimllcatfoa of light
machine oil SAE-20 or .30,

Remove pins and links and clean

as per cleaning Instructions.
Apply DSOHIS liberally.

Romovable Seal and 0|ien
Type Ball, Roller and
Needle Bearings

machine oil SAE-20 or -30.

and repack with I^HIS.

Silver Plated Coniaets and

Wipe clean and apply

Wipe clean and apply I350H4T. **

Light application of light

Primary Disconnect Studs

rials should be inspected for visible leakage

Arcing Coniaets

LUBRICATION

Wlge clean and apply

(Mechanism and Breaker

Linkage)

Alternative Lubrication

[

Sleeve Beartngs

organic insulating materials, these mate
current paths, and necessary action must
be taken to replace insulation that may
have been affected by moisture absorption.

Maintenance Period

Clean as per cleaning Instructions

OSOH4T. ••
Do not lubricate.

Do not lubricate.

CONTACT ARM HINCE
ASSEMBLY

1. Cup Bearing

No lubrication required.

Wipe clean and apply D$0H4T** except

on highly repetitive duty.

In order to maintain reliable opera

tion it is important that all circuit breakers

be properly lubricated at all times. Dur

ing assembly at the factory, all bearing
surfaces, machined surfaces, and all other
parts of the breaker and mechanism sub
ject to wear have t>een properly lubricated
using the finest grade of lubricants avail
able.
However, even the finest oils and
greases have a tendency to oxidize with
age, as evidenced by hardening and dark
ening in color. Elimination of the hardened
lubricant is essential for the proper oper

Booster Cylinders
Trip Shaft Dry Bearings

No lubrlcaUon requlretL
No lubrication required.

Replace rings showing evidence of
excessive wear.

No lubrication required.
No lubrication required.

•• O50H47 supersedes 050HI8.

Fig. IS

Lubrication Chart

desirable to leave the bearings in the
alcohol for a longer time, an inhibited

A simple lubrication

The pins should be removed and ail
old oxidizea grease removed by immer
sion in clean petroleum solvent or similar

alcohol such as is used for anti-freeze
should be used. Even then the bearings
should be removed from the alcohol within

.a might be mistaken for more serious

CHLORIDE. Wipe the bearing clean, ^ply

rkjMt to be forced out from between the

/ • "'ijig surfaces.

'often clear up minor disturbances

A definite lubrication schedule should

be set up taking into consideration the

frequency of operation of the breaker and
local conditions.

Until such a schedule

is worked out, the breaker should be
lubricated at each periodic inspection and
also whenever it is overhauled, in ac

cordance with the lubrication chart. Fig.
It Is also recommended that all cir

cuit breakers be operated at regrular inter
vals to insure the user that the equipment
is operating freely.

The lubrication chart (Fig. 15)

divided into two methods of lubrication.
The first method outlines the maintenance

lubrication which shotild be performed at
the time of periodic maintenance and re

quires no disassembly. The second method
outlines a lubrication procudure similar to
that performed on the breaker at the

factory, but should be used only In case
of a general overhaul or disassembly for
other reasons, or If the operation of the
breaker becomes slower.

General

cleaner.

DO NOT USE CARBON-TETRA-

a small amount of G.E. Lubricant DSCiHlS

trouble.

15.

No lubrication required.

Sleeve Bearings

ation of circuit breakers. Also frequent
operation of the breaker causes the lub-

2. Loose rings between
bushing and contact arm.

Electric

Lubricant

D50H1S

and DS0H47 are available in 1/4# collap

sible tubes. It is so packaged to Insure
cleanliness and to prevent oxidation.

to the entire surface of the bearing and
pin just before reassembling.
Removable Seal and Ooen Type Ball. Roller

and Needle Bearings

The bearings should be first removed

twenty-four hours. Esso Anti-Freeze and
Du Font Zerone are satisfactory for this
purpose.
Precautions against the toxic

by wearing rubber gloves and by using the
alcohol in a well ventilated room; ex
cessive exposure to the fumes is some

times unpleasant to personneL

Washing

the liearings in light oU and drainingshould
follow immediately then sqiply the lubricant.

from the mechanism and disassembled l>y
the removal of the seals or inner race in

RECOMMENDED MAINTENANCE FOR

the case of needle bearings. They should
then be placed in a container of ciean
petroleum solvent or similar cleaner. DO

MAGNE-BLAST BREAKERS APPLIED TO

NOT USE CARBON-TETRACHLORmE. U

Magne-blast breakers applied to re
petitive operation such as switching arc

the grease In the tiearings has become
liadly oxidized it may be necessary to use

alcohol (type used for thinning shellac)
to remove it.
Ordinarily, by agitating
the bearings in the cleaning solution, and
using a stiff brush to remove the solid
particles, the bearings can be satisfactor

ily cleaned.

REPETITIVE SWITCHING DUTY

furnaces, capacitors and motors should be
serviced and maintained according to the
foUowing schedule:

A. Every 2000 Operations, or Every Six
Months - Whichever Comes First

Do not handle the bearings

with bare hands as deposits from the skin

onto the bearings are Inducive to cor
rosion.
If the bearings are touched, the
contamination cah be removed by washing

ating mechanism covers.

In alcohol. After the bearings nave been
thoroughly cleaned, spin them In clean

insulating parts including the bushings
to clean oU smoke deposit and dust.

new light machine oil until the cleaner or
solvent is entirely removed. Allow this
oil to drain off and then repack them im
mediately with G.E. Lubricant DSOHIS being
sure all metal parts are greased. The
removable seals should then be replaced.

Hie inside of the box txirrier should
also be cleaned.

Remove the box barriers and oper

2. With a clean, dry cloth wipe all

3. Primary Contacts - Inspect the con
dition of the stationary contact fingers
and movable contact blocks.
Badly
pitted or burned contacts should be

replaced. (Note: Burned primary con

METHOD OF CLEANING BEARINGS

NOTE: If it becomes necessary to clean
the bearings in alcohol (shellac thinner)

tacts

/^per Arc Runner Atxenbly
5. Upper Arc Runner
6. Side 9tield

7. Lower Arc Runner Atseiebly
S. Lower Coil Connection

Replace con

9. Connection Nut

tacts if necessary.

10. Lower Mounting Support

4. Overloading.
REMEDY: Replace breaker with one of
adequate rating lor present or future
load, or re-arrange circuits so as to

"il'

remove excess load.

5. Primary connections of Inadequate capa
city.
REMEDY: Increase size or number of
conductors or remove excess current

^6. Loose connections or terminal connectlons.

REMEDY: Tighten.

7. Ambient teimerature too high,

Fig. 18

REMEDY: Relocate In a cooler place,

Front View Arc Chute Atseably

or arrange some means of cooling.
REPAIR AND REPLACEMENT

The following information covers in

detail

the

proper

method of removing

various parts of the breaker in order to

2. Remove

the side brace (5) and pole

3. To remove the upper mounting support

(10), Fig.

17, remove the assembly

make any necessary repairs. This section
Includes only those repairs that can be
made at the installation on parts of the

bolt (1), Fig. 16 and connection bolt (2),

breaker that are most subject to damage or

4. Remove the assembly bolts (16), Fig. 17

wear. IMPORTANT: UPONCOMPLETtON

OF ANY REPAIR WORK, ALL BREAKER

pieces (3 and 17), Fig. 17.

3. When reassembling the arc runner as

semblies, check that the spacers (1 and

14), Fig. 22, are correctly installed.
4. Before bolting the upper mounting sup

to remove the lower brace (6).

5. Remove the lowermountlngsupport(14).
Fig. 17, by removing the assembly bolts

INSTALLATION, payingpartlcularattention

(15) and the connection nut (9), Fig. 18.

port in place, make certain that the
upper arc runner assembly is tight
against the arc chute side so that the

gap tKtween the upper insulation (6),
Fig. 22, and the arc chute side (7) is a

to ADJUSTMENTSandFINALINSPECTION.

minimum.

6. At this point the fiber side shields (6),
Are Chute (To inspect or replace blown-niit
colls)

To remove an arc chute, first open the
breaker and remove the box barrier (7),
Fig. 19. Loosen the two upper siq>porting
bolts (2), Fig. 16, and the one lower support
bolt (9) using a 3/4" wrench. By raising

the complete arc chute assembly about

3/8" and sliding it toward the rear of the
breaker it can be removed as shown in
Fig. 16.

To disassemble the arc chute after it

has been removed from the breaker, pro-

^ceed as follows:

i. Remove the caps and assembly bolts

(7, 9, 11 and 13), Fig. 17.

Fig. 18, the upper arc runner assembly
(4) and lower arc runner assembly (7)

5. Make certain ttiat the electrical con

nections (2 and 9), Fig. 18 are tight.

can be removed.

7. Further disassembly .of both the upper
and lower arc runner assemblies can be

done by removing the various screws
and

1/4"

assembly

bolts (not Illus

trated) as shown in Fig. 22.

To reassemble the arc chute to the

breaker proceed as follows:

1. Rest the lower mounting support (10) on
the arc chute mounting bracket (8) as
shown In Fig. 16.

8. The arc chute sides. Fig. 22, can be
separated by removal of assembly bolts

(2 and 4), Fig. 17.

Reassemble the arc chute in the re

verse order.

The following items should

be noted during reasembly:

1. Equally space the fins of the arc chute
sides before bolting together.

to insure that electrical con

nections to the blowout coils are tight.

Fig. 18.

AND MECHANISM ADJUSTMENTS MUST
BE CHECKED.
Refer to the section on

Check

Slide the arc chute forward and lift It

slightly to engage the supporting tolls

(2), Fig. 16, in the slots of the upper
mounting support (3).
3. Tighten the supporting bolts (2 and 9),
Fig. 16.

These tolls serve as both the

electrical and mechanical connections

between the tnjshlng and the arc runners.

GEH-20S4

Magne-blast Circuit Breaker Type AM-4.16-4

1.
2.
3.
4.
5.

Box Barrier Handle
Blow-out Core
Blow-out Coil
Are Runner
Pole Piece

6. Stationary Arcing Contact
7.
8.
9.
10.

Box Barrier
Are Oiute
Pole Piece
Are Runner

11. Blow-out Coil
13. Blow-out Core

21. Operating Rod
22. Stationary Primary Contacts

14. Ftont Bushings
15. Rear Bushings

24. Cup Bearing

16. Frame

25. Yoke

17. Operating Crank
18. Upper Horizontal Barrier
19. Spring Retainer

26. Movable Contact Ana Assembly
27. Movable Arcing Contact
28. Booster Tube

20. Lower Horizontal Barrier

29. Connection Bar

30. Booster Cylinder and Piston

Fig. 19
16

23. Movable Primary Contacts

Cross Section Of Breaker Pole Unit

Magne-blast Circuit Breaker Type AM-4.16-4

GEH-2054

4. Check that the movable arcing contact
(5), Fig. 7, passes through the slot in
the upper arc runner (6) without touching.
Shaft and Self Lubricating Bearings
1.

Remove mechanism cover.

2. Remove mounting bolts for control de

vice (7), Fig. 1, letting control device

hang free.

Do not remove wiring.

3. Remove the trip coil frame mounting

bolts (2), Fig. 21, letting frame hang
free. Also, remove trip coil leatls (4)
from terminal board (4), Fig. 21.

Pivot Pin

2. Opening Spring Unit

4. Remove the trip coilandplungerbracket

(7), Fig. 20, from trip shaft using snap

3. Pivot Pin

4. Trip Coil Uounting Place

ring pliers on ring holding trip coil
plunger assembly.

5. Temlnal Board
6. Svltch Bar

7. Trip Coil Plunger Bracket

5. Remove switch bar (6), Fig. 20, from

latch shaft and snap ring and washers
near bearing.

6. Remove stop bar {13), Fig. 27, for
manual trip rod. Also remove snap
rings and washers next to bearing on
leh side.

7. Using a brass rod approximately 15"
long and 3/8" diameter, drive each
bearing and bearing housing out, taking
the right one out first using the opening
In the left side of the mechanism frame

and the left one out from the opening
made from the removal of the right
hand bearing.
Fig. 20

Opening Soring Assembly
NOTE:

*1
When removing the left handbearing, brass rod as mentioned above may
have to be bent In order to clear latch.

The bearings are self-lubricating

and do not need lubrication.

8. To reassemble, reverse the above pro
cedure except to drive bearings tack In
the mechanism frame, a pipe should be
used so as not to damage bearing sur
face.

NOTE: If latch is to be replaced, the
first seven steps as listed above should
be followed. Also remove the set screw

holding the latch on shaft then place
block between latch and frame to slop
movement, and drive shaft out of latch.

When replacing, make sure spring is In
proper place and one half turn has been

made to wind spring. Also, make sure
latch is in place on stop tar roller
before bearings and shaft are re
assembled.

Trip Latch Roller Bearing
1.

Remove mechanism cover.

2. Remove mounting bolts on control de
vice (7), Fig. 1, leaving control device

hang free.
1. Trip Coil Support
2. tlounting Bolts

3. Trip Coil

4, Trip Coil Leads

Potential Trip Col I

Do not remove wiring.

3. Place block between manual trlprod(6),
Fig. 1, and stop bar on trip shaft. This
holds trip shaft In trip position and
aiiows trip linkage to be free.

GEH-20S4

Ma^e-blast Ctrcuit Breaker Type AM-4.16-4

'orklng through hole on left hand side
•I mechanism, remove snap ring and

vasher from trip roller pin, using snap
ring pliers.
5. Slide trip roller pin |ust enou^ to the
right to allow room to hook snap ring
pliers on ring on other endofpin. Com
press pliers to free snap ring and pry
the pin to the left with screwdriver to
complete the removal of snap ring.
6. Trip roller bearing can now be removed
for lubrication (see section on LUBRI
CATION). Particular attention should be

paid to the location of washers and
spacers.

7. To reassemble, reverse the above pro
cedures.
Contacts

Open the breaker and remove the t>ox
barrier and arc chutes as previously des
cribed. To remove the contacts, proceed
as follows:

Stationary Arcing Contact (10) Fig. 23
1.

Disconnect the contact braids from

contact fingers by
bolts (6), Fig. 23.
2.

removing two

Grasp the lower end of the contact
fingers with pliers and pull contact
assembly downward to remove from
stud assembly.

,'•^">3. To disassemble braids from stud
assembly, remove one bolt (5).

4. To disassemble stud assembly from
contact support, remove two bolts
(6).
5. Reassemble In

the reverse order.

B. Stationary Primary Contacts (9). Fig. 24

1. Upper Arc Runner Spacers

9. Lower Arc Runner

2. Upper Arc Runner Assembly

10. Blowout Coil

3. Blowout Core
4. Blowout 0>il
5. Insulation

11. Blowout Cote

12. Lower Arc Runner Assembly

6. th^per Arc Rxmner

14. Lower Arc Runner Spacers

7. Arc Qiute Side

15. Lower Shield

13. Lower Coil Connection

8. Upper Insulation

Fig. 22

Arc Chute Assembly with Side Renoved

1. Compress the contact spring (6).
2. Remove spring and spring guide (1).
3. Raise the contact finger to clear the
primary contacts stop plate (S) and

lift the finger out of contact support
(7).

To replace the Stationary Primary Con
tacts:

1. Apply a thin coating of D50H47 grease
on the hinged end of the finger (9)

1. Rear Bushing
2. Guide and Support for Arc Chute

then place it on contact support (7)
2.

so that it is retained by stop plate (8).

3. Bolts for Contact Support
4. Con Csc t Suppo r t

Open spring

5. Bolt for Flexible Braid

compressor

(3)

and

6. Mounting Bolt

assemble spring guide, spring and
spring compressor (Fig. 24A).

7. Flexible Braid
8. Connection Bolt

9. Stud for Mounting Arcing Fingers
10. Stationary Arcing Contact Assembly

3. Turn handle (2) in clockwise direc

tion to compress contact spring
(Fig. 248). Hold spring firmly in

11. Spring Baffle

yoke on spring compressor to pre
vent the spring from slipping out of
the compressor.

4. Place washer (not shown) on guide

on top of spring, place top of guide
into hole In spring retainer (4; and

the round end of spring guide in cut
out in primary finger (Fig. 24C).

Fig. 23

Rear Bushing Assembly

Magne-blast Circuit Breaker Type AM-4.16-4

)

GEH-2054

1. Contact Springs

2. Stationory Primary Contacts
3. CUp Bearing
4. Contact Arm

5. Movable Primary Contacts
2. Spring Guide

6. Assembly Bolts
Movable Arcing Contact

2. Handle for Spring Conprosior

6. Spring
7. Contact Support

3. Spring Cempressor
4. Spring Retainer

Stop Plate

8. Assembly Bolts

Stationary Primary

9. Connection Bar

5. Assembly Bolt for Spring Retainer

Fij. 21

10. Piston Asseably

Contact Fingers

Method of Installing Primary Contact Springs Using a Spring Coopressor

5. Hold spring aseinbly firmly in place

3. When reassembling, first insert the

and remove spring compressor.

piston assembly (10), Fig. 25, into
the booster cylinder and reassemble

C. Movable Arcing Contact (7). Fig. 25

the cup bearing (3).

1. Remove the assembly bolts (8).
2.

the nuts from

To replace the bushing, proceed as
follows:

1. Open the breaker and remove the box

barrier and arc chutes as already de
scribed.

E. After disassembly andreassembly ofany
contacts.

(1200 Amp Breaker)
1. Remove

described under INSTALLATION.

ADJUSTMENTS.

assembly

3. Remove the four bolts (3) at the mount

ing flange of the rear bushing being
removed and lower thebushing assembly.

2. Remove the primary contacts (5)
and spacers (not illustrated).

IMPORTANT: DO NOT REMOVE ALL

SDC BUSHINGS AT ONCE.
3. Reassemble In reverse order.

(2000 Amp Breaker)
1. Remove the nuts from assembly
bolts (6).

2. Remove the connection bar (9).

3. Remove the cup bearing (3).
contact arms (4) and

remove the primary contacts (5).
5. Reassemble in the reverse order.
E. Contact Blade Assembly (4. 5. 7). Fig. 25

Remove the upper and lower horizontal

barriers (4 and 5), Fig. 26.

cneCK a u contact aatiiarmprirq

bolts (6).

4. Spread the

Reooval of Contacts

Rear Bushing

4. Replace pin (2), Fig. 8, and con
nection bar (9), Fig. 25.

Reassemble in reverse order.

D. Movable Primary Contacts (5), Fig. 25

Fig. 25

1. Remove the connection bar (9).
2. Remove the cup bearing (3), Fig. 25,
and the pin (2) Fig. 8.

The bushings

4. Referring to Fig. 24, disassemble the
primary contact springs (6) as previsously described.

have been carefully aligned with the breaker

frame, during assembly at the factory, and
it is important that this alignment be main

5. Disassemble the spring retainer (4) by
removing mounting bolts (5).

tained to facilitate installation of the breaker

the metal-clad unit.

It is therefore

recommended that the bushings be removed

and reassembled one at a time.

Also,

before removing any one bushing, measure
the distance from that particular bushing
to adjacent bushings in both directions,

arc

chute

(2)

removing two

bolts (3).
7.

Reassemble in the reverse order. The

guide and support for arc chute (2) is
not symmetrical and must be assembled

location.

correctly to orient the arc chute proper

ly on the breaker.

It is also possible to remove and re
assemble three bushings at one time. If

The longest pro

jection of the bracket should be toward

the lower end of the bushing.

this is preferred, alignment of the bush

mounting bolts. This must be done before
the arc chutes are re-lnstalled.

contact support (4) andguideandsupport
for

so chat it may be re-installed in the same

ings may be accomplished by placing the
breaker in a de-energized spare metalclad unit before tightening the bushing

Referring to Fig. 23, disassemble the

Front Bushing

Open the breaker and remove the box

barrier and arc chutes as already de
scribed.

GEH-2054

Magne-blast Circuit Breaker Type AM-4.16-4

Solenied Pot

2. T«rminjl Board

3. Hire Strap
4. Bottom Plate

5. Control Device Trip
Plunger Rod
6. Guide Studi
7. Armature

8. Step Nuta
9. Front Sti^d Nuta

10.
11.
13.
13.

Plunger Guide
Cloaing Coil Leads
Stop Nuts
Stop Bar

1. Front Bushing
2. Rear Bushing
3. Mounting Bolts
4. Upper Korirontai Barrier
5. Lover Horizontal Barrier

Fig. 26

Fig. 27

Rear View of Breaker with One

Closing Solenoid issesbiy

Arc Chute Reooved

Remove the upper and tower horizontal

moving the four bolts on the underside

tsarriers (4 and S), Fig. 26.

of the armature plate.

1. Open the breaker and remove the open

ing spring unit (2), Fig. 20, by removing

4. Remove iterating rod pin (2), Fig. 8.

the bottom plate with a rope sling or

the pivot pins (1 and 3).
2. Disconnect the two trip coU lead wires
(4), Fig. 21.

hoist and remove the two rear nuts.

3. Remove the two mounting bolts (2) and

5. Remove the four bolts at the mounting
flange of the front bushing being re-

5. Remove the nuts (9) at the top of the

3. Remove the connection bar (9), Fig. 25,
and cup bearing (3).

plate (4) approximately 1/2". Support

moved, and tower the bushing.

6. When reassembling, first

4. Loosen the four nuts under the bottom

mount the

bushing and assemble operating rod pin
(2), Fig. 3. the cup bearing (3) and con
tact arm (4), Fig. 25.
TTie contact
surface at the hinge point of the contact

blade and cup bearing should have a
thin coating of D50H47 grease.
7. Check ail contact adjustments as out
lined under INSTALLATION, AOJUSTMENTS.

front scuds. This permits the bottom
plate, closing coil, solenoid pot (1)
and control device plunger guide (10)

6. To reassemble, first place the closing
coil and spacers on the bottom plate

Raise into position, inserting the

control device plunger guide (10) and
compressing the piston
upper pole piece.

ring on the

7. Tilt the bottom plate downward and re
place the solenoid pot (1) and two front
studs and nuts (9).

Closing Coil
The closing coil is contained within

the solenoid [Mt (1), Fig. 27.

To remove

4. Remove the trip coil (3).
5. After reassembling (in the reverse or

der) check the primary contact gap

to be removed.

(4).

the trip coll support (1).

8. Tighten the four nuts under the bottom

adjustment as explained under INSTAL
LATION, AmUSTMENTS.
Interlock Switch

To remove the Interlock switch (6),

Fig. 10, remove the two mounting screws
and disconnect the lead wires. Reassemble

in the reverse order and check the switch

adjustments as explained under INSTAL
LATION, ADJUSTMENTS.
Latch Checking Switch

the closing coil, proceed as follows:

plate taking special precaution to center

If the closing coil is not firmly held

(3), Fig, 10, (when furnished), remove the

coiL

two mounting screws and disconnect the
lead wires.
Reassemble In the reverse

Open the breaker.

2. Remove the two closing coll leads (11).
Remove the terminal brard (2) from the

solenoid pot and let it hang by the
wires.
Also, remove the wire from
strap (3).

3. Remove the stop nuts (8 and 12) onguide
studs (6), lower the armature (7) and
control device trip plunger (5).

NOTE:

For ease in removing the clos-

ing coil and bottom plate (step S) the

armature and plunger assembly can be

removed from the mechanism by re

the closing coll around the pole piece.

in place, add spacers above the closing

9. Replace the control device trip plunger
rod (5) and armature (7).
10. Recheck the mechanism adjustments as
explained under INSTALLATION, AD
JUSTMENTS.
Trip Coil

To replace the potential trip coil (3),
Fig. 4, proceed as follows:

To remove the latch checking switch

order and check the switch adjustments
as explained under INSTALLATION, AD
JUSTMENTS.
Cut-off Switch

To remove the cut-off switch (1), Fig. 6,
remove the two mounting bolts and dis

connect the lead wires. When reassembling
check tlie cut-off switch adjustment as

explained under INSTALLATION, ADJUST
MENTS.

Magne-blast Circuit Breaker Type AM-4.16-4

CEH-2054

RENEWAL PARTS
It is recommended that sulficient re-

able the prompt replacement ofany'oworn,

such mrto

"ons
Sed
hi h
^ f g iggig
,pa
rts
bccarrled,theamount
time and
expense
Whm
depending
uponshould
the severity
of the ser-

broken, or damaged parts. Astock of ation Uf^.Kry'^S^SSSilf

?lp1ac^ente!

Note: The listed terms "right" and "left" apply when facing the solenoid mechanism end of the breaker.
ORDERING INSTRUCTIONS

ALWAYS SPECIFY THE COMPLETE NAMEPLATE DATA OF BOTH THE BREAKER AND THE
MECHANISM.

SPECIFY THE QUANTITY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF LISTED)
AND DESCRIPTION OF EACH PART ORDERED, AND THIS BULLETIN NUMBER.

STANDARD HARDWARE, SUCH AS SCREWS, BOLTS, NUTO, WASHERS, ETC., IS NOT LISTED
IN THIS BULLETIN. SUCH ITEMS SHOULD BE PURCHASED LOCALLY.

FOR PRICES, REFER TO THE NEAREST OFFICE OP THE GENERAL ELECTRIC COMPANY.

GEH-20S4

Magne-blast Circuit Breaker Type AM-4.16-4

•*N

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

RATING IN
MVA

RATING IN
AMPS

CATALOG # FOR TYPE

AM 4.16 (MVA)-4

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

600
1200
2000
600
1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

619C444 G-5
281B708 G-2
414A116 P-2
414A117 P-1
383A932 P-1
258C616 P-9
421711
407193
258C616 P-13
258C616 P-6
236C791 G-1
236C791 G-4
236C790 G-5
414A116 P-4
6445087 P-1
414A180
414A180
121A5964
6509787 P-1
236C791 P-8
236C791 P-8
236C791 P-8
6557243 P-1
6557243 P-1
6557243 P-2
802B742 G-1
K-6591644 P-7
K-6S91644 P-7
K-6591644 P-7
K-6591644 P-8
K-6591644 P-8
K-6591644 P-8
456A864
P-26
6375521
G-2
6375521
G-6
G-1
6375521
G-5
6375521
6174582
G-1
G-2
6174582
6174582
G-14
6275070
G-1
6275070
G-2
6275017
G-19
6275017
G-20
6275017
G-33
6174599
G-2
6174599
G-6
G-19
6275017
G-20
6275017
6275017
G-33

ALL

6275017

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

ISO, 150A
250, 2S0A
ALL
ALL
ALL
ALL
ALL
150A

150, 150A
250, 2S0A
ALL
150A
ALL
ALL
150A
ALL
ALL
ALL
150A
ALL
ALL

ISOA
ALL
ALL
ALL
ALL

150, 150A
ALL

150, 15QA

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

ALL
600
1200
1200
2000
600
1200
2000
600
1200
2000
ALL

NO. PER
BREAKER

3
3
3
6
6
6
6
6
6
6
3
3
3
3
3
12
12
12
24
12
12
24
6
6
6
3
3
3
6
3
3
6

DESCRIPTION

Booster Cylinder
Operating Rod
Insulating Plate
Upper Runner Insulation Bottom
Lower Shield

Upper Runner Insulation
Insulating Cap
Washer
Lower Barrier
Lower Barrier

Flexible Conn. (Ri^t)
Flexible Conn. (Left)
Stationary Arcing Contact Assembly
Insulating Plate
Buffer

Primary Contact Finger Spring

Primary Contact Finger ^rlng

Primary Contact Finger ^rlng
Primary Contact Finger $ring

Primary Contact Finger
Primary Contact Finger
Primary Contact Finger
Clamp For Buffer
Clamp For Buffer
Clamp For Buffer
Movable Arcing Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Capacitor

Closing coU (125v d-c)
Closing coll (125v d-c)
Closing coll (250v d-c)
Closing coll (250v d-c)

Potential
Potential
Potential
Potential

trip
trip
trip
trip

coil (12Sv d-c
coil i2S0v d-c,
coll (230v a-c
coll 24v d-c)

Potential trip coil ( 48v d-c)
UVD Coll (125v d-c)

UVDColl (250v d-c)

UVD Coll (230va-c)

Current trip coll (3 Amp. a-c)
Capacitor trip coil (230v a-c)
Control device coll (125v d-c)
Control device coil (2S0v d-c)

Control device coil (230v a-c)
(continuous)

G-34

Control device coll (230v a-c)

(intermittent)

GEZ*2BOOO

GENERAL ELECTRIC APPARATUS SALES OFFICES
READY TO ASSIST YOU . . • Wh«fi You Hovo Electrical Problomc . -. Noed Further Information . .. Require Ordering Inttrucllonc
Abilene, Tenoi
Akron 13, Ohio

442 Coder St.
P.O. Box 5276
665 Wo»l Market St.

Albony 3, N. Y

8 Celvin Ave.

Albuquerque, N. Mox

323 Third St., S.W.

Alexondrio, Lo

720 Murray St.

Allentown, Pa..
732 North I6lh St.
Araortllo, Texos
Amorlllo BIdg., 303 Polk St.
Appleton, WifC
510 W. Allege Ave.
Atlonto 2, Go
1860 Poachtree Rd., N.W,
Augusta, Moino
152 Stole St.
Ill Pork Ave.
Boltiinore 1, Md
Bongor, Moino.... P.O. Box 778, 77 Central St.
Boton Rouge 6, lo
3170 Florido Blvd.
Batde Oeek, Mich..607SecurityNolT Bonk BIdg.
P.O. Box 2870
Beoufflont, Toxot
1385 Colder Ave.

Billings, Mont.

Fergus Fotis, Minn
Flint 2, Mich.
Fort Wayne 6, Ind
Fort Worth 2, Tex.
Fresno I, Calif.

Tulore and Fulton St.

Grand Rapids 2, Mich
Greensboro, N. C

P.O. Box 391
19 Chenongo St.
P.O. Box 2602
1804 Seventh Ave., N.

BIrminghom 2, Alo
Bismorck, N. Ook.

P.O. Box 1408
108 W, Washington St.
207 Jo>Fran 8ldg.
P.O. Box 477

Gulfport, Miss.
Kogersfown, Md

Indionopolis 8, Ind.
Jeckson, Mich.

3750 N. Meridian St.
120 W. Midiigon Ave.

Jockson 1, Miss.
Jocksonvtlle 6, Flo.

203 W. Capitol St.
Stotion G^Box 48

4219 Richmond Ave.

1901 Kill St.

Kolomozoo, Mich

2621 Victory Pkwy.
4966 Woodlond Ave.

841 Oak St,
P.O. Box 948
22016 W. Fourth St.
P.O. Box 2004
927 South Burdick St.

Konsos City 5, Mo
106 W. Fourteenth St.
Kingsport, Tenn.. P.O. Box 536,322 Commerce St.
Knoxvilie 16, Tenn..... 1301 Hannah Ave., N*W.
Lake Chorles, la
P.O. Box 5212
422 Seventh St.

lonslng 8, Mich.. .814 Michigon Notional Tower
Las Vegas, Nev
Lexington, Ky
little Rock, Ark.
Los Angeles 54, Coiif.
Los Angeles 5, Calif.

Columbio, S. C.. P.O. Box 1434, 1310 Lody St.
Columbus 15, Ohio

Corpus Christ!, Texos
Dallas 22, Texas

395 East Brood St.

Louisville 2, Ky

205 N. Choparrol

lubbock, Texos

8101 Slemmons Freeway
P.O. Box 26
1039 State St.

Doyton 2, Ohio.

11 W. Monument BIdg.

Denver 1, Colo.

P.O. Box 2331

201 University Blvd.
DesMolnes 12, lowo
Detroit 2, Mich.

2116 W.Grend Ave.
700 Antoinette St.

Duluth 2, Minn.. .

14 W. Superior St.

Bmiro, N. Y
El Poso, Texas
Erie 2, Pa..

Moin & Woodlown Aves.
215 No. Stonton
1001 State St.

Eugene, Ore

P.O. Box 352, 1170 Peort St.

Evonsville 5, Ind

P.O. Box 157
312 N.W. Seventh St.

Fairmont, W. Vo.

P.O. Box 1626

310 Jocobs BIdg.

Postal Annex Box 4156
628 E. Main St,
103 W. Capitol Ave.
212 N. Wgnes St.
Mor.&Def
3325 Wtlshire Blvd.

1216 Storks BIdg.
P.O. Box 1464

P.O. Box 5821

DoveAport«*Bettendorl, lowo

P.O. Box 909
2929 N.W. 29th Ave.

Providence 3, R. L.. .Industrlol Not*! Bonk BIdg.

140 Federol St.

Clevelond 4, Ohio

Portland 7, Ore

Roleigh, N. C.. P.O. Box 2507, 16 W. Mortin Si.

625 Delowore Ave.

CindnnotI 6, Ohio

Peorio, III
2008 N.E. Perry Ave.
Phllodelphio 2, Pe
3 Penn Center PIcrzo
Phoenix. Ariz...P.O. Box 4037, 220 Luhrs Tower
Pittsburgh 22, Po*. .The ORver BIdg., Mellon Sq.

P.O. Box 22045

Buffolo 2, N. Y

Chottonoogo 2, Tenn
Chicago 80, 111

409 S. Seventeenth St.
Orlando, Flo
104 E. Gore Ave.
Posco, Wash.. .P.O. Box 971, 824 W. Lewis St.

764 Asylum Ave.

Boston 1, Moss

Chorlotte 1, N. C

253 Main St., £.
119 N. Robinson St.

1095 Jefferson Blvd.

Johnstown, Fo
Joplin, Mo.

1226 Market Ave., N.
210 Second St., S.E.
P.O. Box 2313
306 MoeCorkle Ave., S.E.
P.O. Box 1285
112 S. Tryon St.
632 Georgio Ave.
840 S. Conol St.

409 Thirteenth St.

Oak Ridge, Tenn
Oklahoma City 2, Oklo
Omoho 2, Nebr.

Houston 27, Texas

Btuefield, W. Vo
P.O. Box 980
704 Blond St., Appolodilon BIdg.
Boise, Idoho
1524 Idoho St.

Canton 4, Ohio.
Cedor Ropids, lowo
Chorleston 28, W. Vo

New York 22, N* Y
570 Lexington Ave.
Niogoro Foils, N. Y.... P.O. Box 715, 44 Falls St.
Oakland 12, Colif.

Hartford 5, Conn.

418 Rotser Ave.

Butte, Mont..P.O. Box 836, 103 N. Wyoming St,

425 Cherry St., S.E.
P.O. Box 1162
301 S. Elm St.

Greenvitle, S. C

Rm. 816,303 No. Breodwoy

Btnghomfon, N. Y.

P.O. Box 197
Rm. 4, Norby BIdg.
653 S. Soginaw St.
3606 So. Colhoun St.
.408 W. Seventh St.
407 Patterson BIdg.

3302 Avenue **A*'

Mocon, Go

P.O. Box 1506, 682 Cherry St.

Manchester, N. H

1662 Elm St.

Medford, Ore.. .P.O. Box 1349, 107 E. Main St.
Memphis 4, Tenn.
P.O. Box 8367
19 South Qevelond

Miomi 32, Flo.
Midwest Oty, Oklo

25 S.E Second Ave.
P.O. Box 5867

Mar. & Def^ 207 Post Office BIdg.
Milwaukee 3, Wise
Minneapolis 3, Minn
Mobile, Alo

940 W. St. Poul Ave.
12 S. Sixth St.
704 Government St.

Nashville 3, Tenn.

1717 W. End Building

Newark 2, N. J
520 Broad St.
New Hoven 6, Conn..
129 Church St.
New Orleans 12, Lo
637 Grovier St.
Newport News, Vo
P.O. Box 1038
311 Moin St., Warwick, Vo.

Howoll: American Foctort, Ltd.# P.O. Bex 3230, Honolulu I

Reading, Po
Richmond 17, Vo.

31 N. Sixth St.
P.O. Sox 2188
700 E. PronUin St.

Roanoke 5, Vo

P.O. Box 871
920 S. Jefferson St.

Rochester 4, N. Y.
89 E. Ave.
Rockford, IIL
4223 Eost Stole St.
Rutland, Vt..
3816 Center St.
Sacromento 14, ColIf.
626 Forum BIdg.
Soginaw, Mich
Second Nctlonol Bonk BIdg.
St. Louis 1, Mo
816 Olive St.

Salt Lake Oty 10, Utah

P.O. Box 779
200 S. Main St.

San Antonio 5, Texos
434 So. Main Ave.
San Bernardino-RIalto, Collf.
P.O.Box 127
337 N. Riverside Ave.

San Diego 1, Calif.

P.O. Box 1222
1240 Seventh Ave.

San Froncisco 6, Calif..... 235 Montgomery St.
Savannah, Go,
40 East Boy St.
Seattle 11, Woth
P.O. Box 1207
710 Second Ave.

Seattle 4, Wash., Mar. & Def., 550 W. Idaho St.
Shreveport, La
206 Beck BIdg.
South Bend 1, Ind
610 N. Michigan St.
Spokone 4, Wash
S. 162 Post St.
Springfield, Ul............. .607 E. Adams St*
Springfield 5, Mess
120 Mopio St.
Stockton, CoHf.
2525 Podfic Ave.
Syrocuse 1,N.Y.. .P.O.Box 1021,3532 JomesSt.
Tampa 1, Flo... P.O. Box 2409,1206 North A St.

Toledo 4, Ohio
420 Mddlton Ave.
Trenton 6, N. J,
*.214 E. Hanover St.
Tucson, Ariz.... P.O. Box 710, 650 N. Sixth Ave.
Tuiso 3, Oklo
320 S. Boston Ave.
Utico 2, N. Y.
258 Geneseo St.

Washington 5, D. C
Wheeling, W. Vo,
Wichita 2, Kan.

Worcester 5, Moss.
York. Pa..

Youngstown 7, Ohio

777—14th St.. N.W.
40 Fourteenth St.
200 E. First St.

288 Grove St.
56 N. Harrison St.

272 E. Indlonolo Ave

Canada: Canadion General Electric Company, Ltd., Toronto

GENERAL ELECTRIC SERVICE SHOPS
WK9I YOU NEED SERVI.CE • . . Thete G^E service theps will repair,
recondition, ond rebuild your electric opparolut. The fecllllles ore

*«voilabie day and night, seven days o week, for work In the shops
or en yeur premises. Lotest foctery methods ond penuine 0*E renewal

Albony, N. Y
AEIenfown, Po
Applcton, Wise

1097 Control Ave.
668 E. Ifighland St.
MIdwoy Industrlol Areo,

County Trunk (P), P.O. Box 83
Atlonto-Chombloe, Go

5035 Poochtree
Indus. Blvd.

'Arkansas City, Kon

P.O. Box 526

Boltimoro 30, Md
Birmingham, Alo
Boston^Medford 55, Most
Buffalo II, N. Y

920 E. Fort Ave.
7—18th St., S.W.
3960 Mystic
Valley Pkwy.
318 Urbon St.

Dolios, Texas
Davenport, lowo

ports ere used lo mointoln peak performance of yeur equipment. For
full Information about these services, contact your nearest service
shop or soles office.

3202 Monor Way
P.O. Box 630

'Ontario, Calif
Philadelphia 24, Po
Pittsburgh 6, Po.
PlantsvKle, Conn
Portlond 10, Ore

3353 Larimer St.
.5950 Third Ave.

Ft. Wayne, Ind

606 W. Superior St.
1062 E. 28th St.

Houston 20, Texas. . . .5534 Horvey Wilson Dr.
Indianapolis 22, Ind.
Johnstown, Po

Konsos City 20, Mo

1740 W. Vermont St.
841 Oak St.

3525 Gardner Ave.

4360 W. 47th St.

Los Angeles 1, Collf..
Louisville 9, Ky
Midland, Texos

6900 Stanford Ave.
3900 Crittenden Or.
3404 Bonkheod Hwy.

Cincinnati 2, Ohio
'Gndnnoli 3, Ohio

444 W, Third St.
260 W. Mitchell Ave.-

Milwaukee 3, Wise.
Minneapolis 12, Minn

940 W. St. Paul Ave.
2025 49th Ave., N.

Cleveland 4, Ohio

4966 Woodland Ave.

Chorleston 28, W. Vo... 306 MoeCorkle Ave., $.E.
ChorloHe 8, N. C
2328 Thrift Rd.

Chicago 32, III.

Columbus 23, Ohio.; .

Corpus Christi, Texos
*•60

Ooklond, Colif.

1039 State St.

Denver, Colo
Detroit 2, Mich.
HIaleah, Fla

* Denotes Aircroft Service Shops

2128 Eokin Rd.

New Orleons, Lo
2815 N. Robertson St.
New York-N. Bergen, N. J.. .6001 Tonnelle Ave.

115 Busse St.

*M^wYork-Linden,N.J.. 1611 W. Elizabeth Ave.

Richmond 24, Vo
Roonoke 7, Vo
Sacramento, Calif..'.

3400 Wood St.

Ont. Int'l Airport*
1040 E. Erie Ave.
6519 Penn Ave.
370 Atwater St.
2727 N.W. 29th Ave.

1403 Ingrom Ave.
115 Albermarle Ave., S.E.
99 N. 17th St.

St. Louis 10, Mo.
1115 East Rd.
Salt Lake Oty 4, Utah. . .301 S. Seventh W. St.
Son Francisco 3, Calif.
1098 Harrison St.

Seattle 4, Wash
'Seattle 8, Woih
Spokane 3, Wash
Tompo 1, Flo
Toledo 4, Ohio

York, Pa..
Youngstown 7, Ohio

GENERAL ELECTRIC COMPANY, PHILADELPHIA, PA.

3422 First Avo., S.
220 Dowson St.
S. 155 Shermon St.
P.O. Box 1245
405 Oeorbem Ave.
54 N. Harrison St.
272 E. Indlonolo Avo.

GEI-88761,.�

INSTRUCTIONS
ANO
RENEWAL PARTS

SUPERSEDES

TYPES
AM-4.16-250-6C

�·
r,(Z)T,

AM-4.16-250-7C
AM-4.16-250-7H

CONTENTS

�

r·Y

Introduction ............�.l

Receiving, Handling
and Storage ........
.•..1
�
Installation .... �········2
\l..
Description of
Operation ...·
·..........4
�
Adjustment��·············6
Generalj&��ance ..........12

r�

. ...
I
.,
i

Renewal�................28

•

SWITCHGEAR DEPARTMENT

GENERAL

u
•

MAG NE-BLAST
AM-4.16-250-6H

GEi·��

fl ELECTRIC

PHILADELPHIA, PA.

OEI-88761
MAGNE-BLAST CIRCUIT BREAKER

AM-4.16-250-6
AM-4.16-250-7
Letter Designation -B^C, and H, used inuaediately followi
the model number indicates basic design features.
INTRODUCTION

The magne-blast circuit breaker is the removable interrfto'Hfo^lement

for use in vertical-lift metal-clad switchgear, to provj^^^iable
control and protection of power systems. Among the ms^^k^antages of
metal-clad switchgear are added protection to equipm|rrcroM personnel,
compactness, sinQ>lified installation and reduced midnl^Snce. In keep
ing with these features the magne-blast breakers aA^yigned for interchangeability and maneuverability, together wj^M^iuability and
low maintenance requirements.

The magne-blast circuit breaker operates o
can be interrupted in air by sufficiently
This is accomplished by means of a stro
the arc and forces i t into intimate con
Ci

b•st
tn

terial. A sturdy, reliable operating
ance and long life.

nciple that an arc
ng and cooling it.
ic field that lengthens
cool dielectric maSm assures low mainten-

The AM-4.16 magne-blast breaker is aM^Sble in a number of current
ratings.

Refer to the breaker nameml/By'for the complete rating in

formation of any particular brew». %0ne short circuit conditions to

be in^osed on the breaker must•^yexceed its rating, nor should it be
called upon to operate at voUHaglCor currents greater than those

>
o
o

given on the nameplate. Sincej^^book is written to cover several
ratings of breakers that arei0)w^ same general design, all instruc
tions will be of a general cftgr^ter and all illustrations will be

typical, unless othex a damage claim should be filed immediately with the trans-^
portation company and the nearest General Electric Sales Office shouli
be notified.

It is e;q>ected that due care will be exercised during the unpacking
and installation of the breaker so that no damage will occiir from
careless or rough handling^ or from e:q>osure to moisture or dirt. ^
ed ^th
Loose parts associated with the breaker are always included
ia^the
same crate. Check all parts against the packing list to
that
no peu>ts have been overlooked.
Storetge

It is recommended that the breaker be put into service

its permanent location.

Lsdiately in

If this is not possible^ th^kJ^ owing pre-

cautions must be taken to insure the proper storag^^^^tyhe

breaker:

1. The breaker should be carefully protected agai^k^ondensationj

preferably by storing it in a warm.dry roo^iL sjfcje water absorption

has an adverse effect on the insulation paru^^ircuit breakers
for outdoor metal-clad switchgear shoulM|^\Mred in the equipment
only when power is available and the h|^l^^%re in operation to

prevent condensation.
2. The breaker should be stored in a

l^^location, free from corro-

sive gases or fumes; particular a
equipment from moisture and cems
very corrosive effect on many
3. Machined parts of the operati
with a heavy oil or grease t
I f the breaker i s stored for

periodically to see that rusj
mechanical condition.

Sho"^'

atmospheric oonditions, s
before i t is placed in

ild be taken to protect the
as this combination has a

anism, etc., should be coated
ent rusting.

ngth of time, it should be inspected
has not started and to insure good
breaker be stored under unfavorable

hould be taken to dry out the breaker

INSTALLATION
1. Remove the box
to ascertain

dition.

Chi^k

Refer to s,

and front cover and make a visusil inspection
breaker and mechanism is in satisfactory con)earing surfaces of the mechanism for lubrication,

m Lubrication (page 14)

2. Charge the bicker closing springs manually using a 3/8" ratchet
wrench to turn the driving eccentric (6) Fig. (4).
eccentric

counter clockwise

Turning the

will advance the x'atcher wheel and

compress tne springs,
springs have reached the fully charged position the indi-

•) Pig. (4) will read "CHARGED", and the driving pawl will
from the ratchet wheel teeth.

Additional turning of the

ric will not advance the ratchet wheel.

GEI-88'

Insert the spring blocking device (4) Fig. (4) and manually^li

cheirge the springs against the pins by pushing the manual^i^fi^se
button (1) Fig. (4). The springs are now blocked and slc^c^slng

of the breaker contacts can be accomplished by again turnlnafthe
driving eccentric with a 3/8 ratchet wrench.

During the slow closing operation check to Insure that tlfe mechanism
does not stick or bind during the entire stroke,

latches se

curely In the closed position, and that It trlpi^MeAr when the man
ual trip lever Is operated. The breaker shoul^^H^re operated
electrically until It has been operated severajOk^s manually to

Insiire freedom of action.

At this time, als<^gt;p3c the following

adjustments:
a.
b.
c.

Primary contact wipe
Arcing contact wloe
Primary contact gc^p

'Refer to page
Refer to page
Refer to pa

"DO NOT WORK ON EITHER THE BREAKER
SPRINGS ARE BLOCKED AND THE OPEN^G
OR MECHANICALLY BLOCKED.
THIS
ACCIDENTAL CLOSING OR TRIPPING

ANISM UNLESS THE CLOSING
GS HAVE BEEN TRIPPED OPEN

ON IS REQUIRED TO PREVENT

After the adjustments have beetV^i€Cked, the springs can be un

blocked. Rotate the drlvlngysm^litrlc until the Indicator reads

"CHARGED" and the ratchet_$|m|^to longer Is advanced. The blocking^

device can now be remov

ult breaker and operate electrically

3. Attach test coupler
several times.

Check

trol voltage as described under "CON-

TROL POWER CHECK".
NOTE:

I f the bre

test at 1300 vo]|ts
connection.

cause damage J;o

4. Remove the

ondary wiring Is to be given a hl-potentlal
ve both the motor leads from the terminal
disconnect the motor from the circuit may
Indlng Insulation.
upler and replace box barrier.

3. If breakei^^l^Been stored for a long period of time,

I t i s recom-

mended. tlm7ttie Insulation be checked with a standard 60 cycle high
Refer to Insulation Test (page 23).

6. Lu

he silver portion of the primary disconnect studs by

small amount of contact lubricant D30H47 to form a thin
the ball contact.

Refe^ to metal-clad Instruction book GEH-I802 for final Instructions
toe
efore Inserting the breaker Into the metal-clad unit.

GEI-88761

'Description op operation
The magne-blast breaker is composed of two major parts^ the breaker
element and the operating mechanism. The breaker el^nent comprises
three similar pole unlts^ each pole unit consisting of main and arcl
contacts, an Interrupter, and an enclosing box barrier that segregates
the Interrupting units from each other to provide Insulation between^
phases as well as from each phase to ground. The primary connactlons

ising the operating mechanism linkage to collapse. The
in the opening springs is thus released, opening the
breaker.
During this operation, the trip coil circuit is deenergized,
and upoifr completion of the opening operation, the operating mechanism
eturned to its normal position, ready for closing.

Pig. (5'
energy

GEI-88761
As the breaker opens, the main contacts part first, shunting the
through the arcing contacts.
An arc forms as the arcing contacts p

See Pig. (7).

As the movable arcing contact (27) Is withdrawn thro

the slot or between the arcing probes on the arc runner, the upper e

of the arc Is transferred to the upper arc runner (4).

To assist the

Interruption at this point, a stream of air Is emitted from the booster

tube (28) and forces the arc onto the lower arc runner (10). tetabllsh-

ment of the arc on the runners automatically Inserts the b^v£)|f0y:olls
Into the circuit. Introducing a magnetic field between the^^Oi^gpleces
which tends to draw the arc away from the arcing c o n t a c t I n t e r
rupter contains one upper magnetic blowout coll and one l^vp^blowout
coll each Individually connected In series with Its resjl^^
arc

run-

ner. The arc Is forced outward along the diverging ar(( v r u m ie r s by the
magnetic field.

iDP

At the same time, the arc Is being forced Into the £ll|c chiute (8) which

Is composed of a series of gradually Interleavlng^^^at
atlng

These fins, which project alternately from th
faces of the chute, elongate the arc Into a g:
pentlne path, so that the electrical resls
Is rapidly Increased and the heat from th
creased resistance reduces both the magnl

the current, and at an early current-zerq,
the gases produced by the arc so cooled
Itself, and Interruption occurs.
lanual tripping follows the same pjoc
energizing the trip circuit.

fins.

wo/olfc
tilD^jKoslte
Inner surdeepening serthe path of the arc
absorbed.

The In-

d the phase angle of
rc path Is so long and

the arc cannot reestablish

except that Instead of

Pig. (2) Is used.

Trip Free Operation

If the trip coll circuit Is
the trip plunger will force

trip roller (9) causing th%
breaker to re-open.
The
stroke and the springs

d while the breaker Is closing,

latch (8) Pig. (5) away from the
'nlsm linkage to collapse and the

cam (16) will complete Its closing
re^charge as In a normal closing operation,

ADJUSTMENTS

All adjustments

lie checked during periodic Inspections and

whenever It becama^iiTOSsary to repair or replace parts that have be
come worn or
while In service. The following adjustments
are listed In^G^o^er In which they are to be checked. First, how
ever, remove tnlu^aker from the metal-clad unit and remove the box
barriers and froxi^ cover.

"DO NOT

,RK 0# EITHER THE BREAKER OR MECHANISM UNLESS THE CLOSING

SPRINGS

BLOCKED AND THE OPENING SPRINGS HAVE BEEN TRIPPED OPEN

OH MECHA^

DENTAI^

.Y BLOCKED.
THIS MEASURE IS REQUIRED TO PREVENT ACCIING OR TRIPPING."

GEI-88761
Primary Contact Wipe

When the breaker is closed^ as shown in Fig. (8),
mary contacts (1) should rise 5/16"-f- 0 —l/l6".

the statlonar:
Before chec

dimension be sure the mechanism is re-set so that the prop pin'

Pis* (5) is resting on the prop. To obtain the proper contact ^Bffustment, open the breaker and, referring to Pig. (9), loosen the check
nut (4). and turn the adjusting nut (3). Screwing up on the adjusting
nut will decrease the primary contact wipe, down will
Tighten the check nut, close the breaker and recheck
the primary contact wipe correctly adjusted, the cle^

contact arm (6) and the buffer block should be l/l6"^
shown in Fig. 8) when the breaker is fully closed.

ease i t .
e.
With
etween the

eater (as

Arcing Contact Wipe

Refer to Fig. (8).
touch.

Close the breaker until

This can be determined with the use

tester such as a light indicator or bell se
gap between the stationary primary conta.

contact (2) should be 5/16" or greater,

ng contacts Just
rcviit continuity
this position, the

^and the movable primary
etting has been made in

the factory and no adjustment is pro
wipe of less than 5/l6"
is usually an indication that the ar
tacts need to be replaced,
When making this check, also see tha
la'SKch^ ovable arcing contact (5)
passes between the slots or the arc
bes on the upper arc runner with-

out touching, whichever is applicablSL
Primary Contact Gap

Refer to Fig. (9). With th
button allowing the breaiker^
contacts open wider by han

ker closed, press the manual trip
p open normally. Do not force the
gap betvfeen the stationary primary

mary contact (6) should be 3-13/16" +
ap, loosen the check nut (17)* Pig* (5)
on stud (19). Screvring the adjusting
^rimary contact gap. Tighten the check nut
^p (close and trip the breaker before check-

contacts (5) and the movab
1/8" —3/l6". To change
and turn the adjusting
nut down will decrea
and remeasure the

ing the measureme:
Trip Latch Wipe

Refer to Fig.

(9) should
film of

tripping
rests aj
ual insped
correct.

le wipe of the trip latch (8) on the trip roller
3/16" to 1/4". This can be measured by putting a
she latch (8), closing the breaker part way, and
ichanism has the proper trip latch wipe vrhen the latch

le stop pin (23).

No adjustment is provided and a vis-

is usually all that is required.

If this setting is not

for insufficient travel of the trip shaft (7).

;mEN.WORKING ON THE MECHANISM IN THE CLOSED POSITION, KEEP FINGERS

CLRAlVoF THE LINKAGE, AS ACCIDENTAL TRIPPING CAN CAUSE SEVERE INJURY.

GEI-88761
Trip Latch Clearance

liefer to Fig. (5).

With the breaker in the tripped position and the

closing springs charged, check the clearance between the trip latch

and the trip roller (9).

It should nieasiu?e 1/32" to I/I6".

e open when the breaker is closed. The "a" contacts should
close^hen the breaker primary contact gap is a minimum of 1". The "b"
/^^oirta^w need only to be checked to see that they are open when the
_or^llfe^ is closed. No adjustment is provided and a visual inspection
J^3k§ually all that is required.

GEI-8i

Driving Pawl Adjustment

Hie driving pawl (5) Pig. (4) must advance the ratchet wheel (3)
(3) sufficiently on each stroke to allow the latching pawls (1) to
fall Into the ratchet teeth.

Ihls should be checked with the maximum

closing spring load against the driving members.

With the mechanism

unblocked^ hand charge the closing springs with the manua]^M?^eii^

wrench until they are slightly more than half charged,

:rotate

the charging wrench until the driving pawl (3) Fig. 4 ha^fc^ffve:
eled
through Its return stroke and check the maximum cleara^ffcM^twei
tween

pawl and the ratchet tooth. Rotate the charging wre
Ing pawl has advanced the ratched tooth to Its maxim
check the clearance between the ratchet tooth and

(1) Fig. (3).

The clearance should be approxlma

In either case.

If adjustment Is required for either pawl
fully charged and blocked. Loosen seven m

(13) and move entire motor assembly to t^
ance Is under the minimum a t the drlvl

approximately twice the dimensional Int
certain the motor assembly Is moved sf
tighten the one bolt on the right
assure proper alignment. After tl
springs should be released and

chlng pawl
rual for both

the driving and latching pawls and not less tha

under the minimum at the latching pawls;

the

11 the drlvvel.
Now

gs must first be

port bolts (1) Fig.
the clearance Is
the front I f the clear-

Move the motor assembly
required at the pawl. Be
forward or reazward and

the mounting frome first to
the remaining bolts the
nee again checked as described

above.

AUXILIARY DEVICES

Latch Checking Switch

Refer to Fig. (12).

Ro^at'

the left side of the me

open the latch check:
to reset slowly and
using a circuit con
set.

The contacts

the gap between tl

crank (7) Is 1/U

trip latch (4) clockwise (looking at
^) by pressing the manual trip lever to
:h operating arm (3) < Allow the trip latch

Lne the point at which the contacts make by
tester^ such as a light Indicator or bell
e latch checking switch should Just make when

latch (4) and the stop pin (3) located on the

T^ere should be a minimum of 1/64" between the
(12) and the switch support (1). To obtain
atch checking switch (2) bend the latch checking
(3).

operating a]

adjustment ^
switch ope|#t^
Plunger Inter

Refer to Flg^ (13).
ical djltetance

With the breaker In the closed position, the vert

A" from the top of the Interlock bolt (1) to the bottom

of th^,^
th^^^vatlng bar (3) should be 16-21/32" plus or minus I/16". To

chaai^^m.s adjustment, add or remove washers (2).

QEI-88761
Spring Release Interlock

A spring release Interlock shown In Fig. (14) v/ill assure that th

Control switches are provided for thJ^

It is also possible to trip or clo^T

the breaker manually by pressing the manual trip lever (11) Pig. (2W J

or the manual close button (7).
Before the breaker is finally raised into position in the metal-clafi

unit, rub a small amount of G-E contact lubricant D50H47 on

sil-

vered portion of the breaker studs to form a thin coating^o
tacting purposes.
GENERAL MAIin?ENANCE
•••

Dependable service and safer power equipment are cont
unfailing performance of the power circuit breaker,
service, i t is recommended that a definite inspect
schedule be set up and followed, as serious shutdq

avoided by locating potential sources of trouble^

THE CLOSED POSITION UNLESS THE PROP AND^
WIRED OR BLOCKED TO PREVENT ACCIDENTA:

^BREAKER OR MECHANISM WHILE THE SPR
SECURED IN THAT POSITION B7 THE

maintenance
often be

early stage,
so vitally im-

A periodic lubrication of parts subject to w
portant for the successful operation of the
BEFORE AN7 MAINTENANCE WORK IS PERFORMED
TROL CIRCUITS ARE OPENED AND THAT THE
METAL-CLAD UNIT.
DO NOT WORK ON THE

upon the
intain such

TAIN THAT ALL- CO)IREMOVED FROM THE
MECHANISM WHILE IN
LATCH HAVE BEEN SECURELST
ING.
DO NOT WORK ON THE
CHARGED UNLESS THE7 ARE
E SPRING BLOCKING DEVICE.

Periodic Inspection

should be determined by each

The frequency of periodic insp
operating company on the bas

Ehe number of operations (including

switchir^g), the magnitudej3f(

^nts interrupted, and any unusual
to time. Operating e:q)erience will
xedule which will give assurance of

operations wliich occur f
soon establish a maintena;

proper breaker conditic

fault duty and repetitij
recommended after any. "

tions list the main p(!

ber of general recoj

installations where a

combination of

ration is encountered, an inspection is
fault operation. The following instructo be included in an inspection and, a numions.

Arc Chutes
I t i s not ne

of damage or
specting an arc
points noted:

^to inspect the arc chutes unless there is evidence
arc chutes are removed for any reason. When inlute, i t should be disassembled and the following

rmed over the surface of the arc chute must not be removed,

particles collected in the chute should be blown out.
hich have formed in the fins of the arc chute are to be ex-

in ceramic materials of this type when subjected to the severe
f an arc. These cracks do not interfere with the operation of
device in any way and should be disregarded.

GEI-88

3. If the arc chute has suffered any mechanical injury due to
or accidental striking, resulting in the actual breaking
replacement of the chute will be necessary. Small broker

fins.

on the exhaust end of the chute will not interfere with

formance and can also be disregarded.

4. The plastisol flexible covering for the pole pieces (17 & 18) Pig.
(16) and the upper mounting support (10) Pig. (l6) shoul# be inspected for breaks in the insulation.
If there arj
in the insulation they should be repaired or t

pies or breaks
eplaced.

Breaker Contacts

By removing the box barrier the movable and sta
and the movable arcing contacts can be inspecl

ing contacts can be inspected only after rern^

he arc chute assemI f the contacts are
a fine file.

bly, as explained under REPAIR AND REPLACl
burned or pitted, they should be made smoQj
After completing inspection of the co
ments as specified imder ADJUSTMENTS.

y primary contacts
e stationary arc-

check the contact adjust-

Mechanism

A careful inspection should be m;
and broken retaining rings.
A1
should be inspected for any ev:
Lubricate the mechanism as

check for loose nuts or bolts

roller, and latch surfaces
of damage or excessive wear,
below, then, using the manual

breaker several times to make
charging wrench, open and
certain that the mechani sm^^K rates freely throughout its entire stroke,
as specified under ADJUSTMENTS. Check
Check the mechanism adjui^"

sSl^

all terminal connections.
Bushings and Insulati
The surface of the

vent moisture abso,

damaged, i t sho
with either cle
hard.
All other
Smoke or
and i f

8 should be kept clean and unmarred to preI f the insulation surface should become

sanded and cleaned, and should be refinished
ish or clear resin. Allow to dry smooth and

on parts on the breaker should be kept clean and dry.
lected between inspection periods should be wiped off,
is apparent, heaters should be installed to insure dry-

ness.

Insulat

When iiuulation has been repaired or replaced, or v;hen breaker has
b^n stored under adverse conditions, i t is recommended that the in.tion be checked before the breaker is placed in service.
A stand-

"0 cycle high potential test at 14,000 volts RMS will normally inte whether the breaker is satisfactory for service.
V/ith the
reaker contacts in the fully open position, apply the high potential

o each terminal of the breaker individually for one minute with all -f)
other terminals and the breaker frame grounded.

After high potential

GEI-88761

tests are made on organic insulating materials, these materials should h"
^\nspected for visible leakage current paths, and necessary action mus
taken to replace insulation that may have been affected by moisture a
tion.

If the breaker secondary wiring is to be given a hi-potential test
volts, remove both of the motor leads from the terminal board. Failure to
disconnect the motor from the circuit may cause damage to the windJ^ig in
sulation.

LUBRICATION

In order to maintain reliable operation, i t is important
breakers be properly lubricated at all times. Most of

rolling surfaces utilize a new type of dry lubrication t!
ho maintenance and will last the life of the equipme

and surfaces listed in the chart Pig. (20) require
been properly lubricated, during assembly at the fa^^r;

grades of lubricants available.

However, even

have a tendency to oxidize with age, as evide,
ing in color. Elimination of the hardened
proper operation of circuit breakers.
Als
breaker causes the lubricant to be forced

surfaces.
A simple lubrication will ofte
which might be mistaken for more serious
A definite lubrication schedule shoiQ

frequency of operation of the
such a schedule is worked out, th
periodic inspection and also whe

the lubrication chart. Pig. (20
breakers be operated at regular
equipment i s operating freely.

The lubrication chart. Pig.

a l l circuit

arings and
will require
hly few bearings
ation.

These have

using the finest
oils
and greases
t]|0|iC^est
ardening and darkeni s essential for the

t operation of the
m between the bearing
up minor distiu*bances

up taking into consideration
hd local conditions.

Until

amp should be lubricated at each

i t is overhauled, in accordance with

i s also recommended that all circuit
als to insure the user that the

divided into two methods of lubrication.

The first method outlines^*t4J^|^ntenance lubrication which should be per

formed at the time of perjftal^ maintenance, and requires no disassembly.
The second method outl^brication procedure similar to that performed

on the breaker at the fmfcoy, but should be used only in case of a general

overhaul or disassembij^f^^other reasons, or if the operation of the break
e r becomes slower.

General Electri

lapsible tubes

nts D50H15 and D50H47 are available in 1/4# colso packaged to insure cleanliness and to prevent

oxidation.

Method of Cle

Whenever cleaning is required, as indicated in the lubrication chart, the
following., procedures are recommended:
nss

eve bearings used throughout the linkage utilize Teflon surfaces and
equire lubrication. After a number of operations, the surface will
a

thin black film.

Do not remove this film \mless there i s evi-

bf outside contaminates, such as dry or heirdened grease.

If contami-

aEI-887
nants are present they should be removed by Immersing the link and
ing in clean petroleum solvent or similar cleaner and using a stif
Do not remove the bearings from the links.
DO NOT USE CARBON T.

RIDE.

The hinge of the primary contact arm (24) Fig. (7) should be dis9tefmbled,

cleanedj and lubricated with G-E D$0H47 lubricant at general overhaul per
iods.

The main shaft bearings (24) Fig. (5) and the driving pat

^er bearing

should be removed, cleaned, and lutfricated with 6-E D5c

ricant a t

general overhaul periods.
Roller & Needle Bearings

The cam follower bearings (6) Fig. (3), latch roll
shaft bearings (23) Fig. (3) should be f i r s t rei
the inner race disassembled.
They should then
clean petroleum solvent or similar cleaner.
IDE.
If the grease in the bearings has b

necessary to use alcohol (type used for t
Ordinarily, by agitating the bearings i:

a stiff brush to remove the solid partf

^aring (9), and cam
bm the mechanism and
ced in a container of
USE CARBON TETRACHLOR-

ly oxidized, i t may be

shellac) to remove it.
eaning solution, and using
he bearings can be satiss with bare hands as deposits

factorily cleeuied. Do not handle the
to corrosion.
I f the bearfrom the skin onto the bearings eu>e i
removed by washing in alcohol.
ings are touched, the contamination c
After the bearings have been thoroi;ufM^%leaned, spin them in clean new

light machine oil until the clea^f:zTapitoolvent
this o i l to drain off and then

e greased.

D3OHI3 being sure all metal p
then be replaced.
NOTE:

I f i t becomes necess

thinner), be sure the alcoh
bearings to remain in

Esso Anti-Freeze an

The removable seals should

lean the bearings in alcohol (shellac
perfectly clean, and do not allow the

1 n^ore than a few hours.

If it is desir-

the alcohol for a longer time, an inhibited

able to leave the bear
alcohol such as is

be2u*ings should be

is entirely removed. Allow^

l^ol^hem immediately with G-E lubricant

ti-freeze should be used.

Even then the

rom the alcohol within twenty-four hours,
mt Zerone eu>e satisfactory for this purpose.

Precautions againa^ldiSybbxic effects of the alcohol must be exercised by
we£n>ing
rubber glofesj^d
by using the alcohol in a well ventilated room;
he fumes is sometimes unpleasant to personnel,
excessive es^os
Washing the ^a:
ly, then appJlW:'!

Bearings

in the light oil and draining should follow immediate'ubricant.

pressed into the frame or other members such as the ec

centric drxuTh^rings (7) Fig. (I5j) should not be removed. After remov

ing the shaf^Bnd inner race the bearing can usually be cleaned satisfactorily with petroleum solvent or a similar cleaner and a stiff brush,
Follow the 4^rocedure outlined above using a light machine oil and G-E
lubric

D3OHI3 before reassembling the inner race and shaft.
urfaces

,ber of rolling and rubbing surfaces in the mechanism have been lubri-r*s
^ with a baked-on, dry, molybdenum disulfide coating.

This requires

aintenance and should last the life of the breaker.

GEI-88761

RECOMMENDED MAINTENANCE FOR MAQNE-BLAST BREAKERS APPLIED TO REPETIT
SWITCHING DUTY

Magne-blast breakers applied to repetitive operation such as swil
arc furnaces and motors should be serviced and maintained according to

the following schedule:

A. Every 2000 Operations, or Every Six Months - Whichei^r

First

1. Remove the box barriers.
2.

Wipe all insulating peirts clean of smoke depo
a clean dry cloth, including the bushings, and

dust, with
inside of the

box barriers.

3. All areas in the throat area of the arc c

cleaned by using sandpaper.

ISiis clean

time the arc chute i s removed.
The arcl
cleaned.
Whenever the arc chute i s

should be blown out before replac

4. Primary Contacts - Inspect the c

tact fingers and movable contact|

contacts should be replaced.

When
minimum specified und<
placed.
The contacts
damage using a mirr
mally i t will no% b
2000 operation si

hutes.

of the stationary cons. Badly pitted or burned
e:~ Burned primary contacts in-

If the

d or galled, they should be
filed.
After contact dressing

smoothed with crocus d o

5. Arcing Contacts -

fins should not be
loose dust and dirt

contact replacement).

dicate the probable need for
contact surfaces are only
the primary contacts sho

ihould be thoroughly
uld be performed any

greased lightly with D50H47.
cing contact wipe is less than the
STMENTS, the contacts should be re-

d be inspected for uneven wear and/or

nspect the stationary contacts.
Noressary to remove the arc chutes for this
unless inadequate wipe or contact condition indicate
or replacement. When the arc chutes are
removed, the e
braids, coil protectors, and other parts
subject to ax^
ould
be checked for possible cleaning or rersAng
placement,
t grease the arcing contacts xmder any circumstances.

6. Check
INSP

er and mechanism adjustments as summarized imder
TEST. The necessary readjustments shoiild be made
under ADJUSTMENTS.

The br^lfcer and operating mechanism should be carefully inspected
for loose nuts, bolts, retaining rings, etc., all cam, latch and

^ollei^ surfaces should be inspected for damage or excessive wear,
e

buffer blocks and their retainers on the bottom of tne sta-

nary contact support should be inspected for possible need of
lacement.

8. The contacts of the control relay should be Inspected fo:
and cleaned If necessary.

<^wjt

9. Lubricate the breaker operating mechanlsin In accordan
table under LUBRICATION.

; h the

10. Inspect all wiring for tightness of connections and p<^slble dam
age to Insulation.

11. After the breaker has been serviced^ It shoun^6^!Lowly closed

and opened, as described In INSTALLATION, to^^^s^e there Is
no binding or friction and that the breaker^JMj^cts can move
to the fully opened and fully closed postl^icy Its electrical

operation should then be checked using ej^tnlH^he test cabinet
or the test couplers.
B. After Every 10,000 Operations
1. In addition to the servicing doi
chutes should be removed from

permit a detailed Inspection

,000 operations, the arc
:er and disassembled to

atlon, blow-out colls, arc
ome contaminated by arc pro-

runners and assemblies which
ducts.

2. The blow-out colls should b
sulatlon has been cracke
heat so that the turns

each other, the colls/

>u:

^arefully examined and If the Inink or eroded from arc action and

^colls are not fully Insulated from.^
^be replaced. All connections should

be checked for tlgh
Inspected and replaced when any part

3. The arc runners shq
of their area has
thickness as a re

4. Check the st
tacts are In

educed to 23^ of the original metal
f

arc erosion.

arc contacts to assure that the arcing conondltlon and that their connections are tight.

5. Insulatlngmi^^lal that Is carbonized and cannot be satisfactor
ily cleai^ psbuld be replaced.

6. Any panii^lmaged or severely burned and/or eroded from arc action
shoulclUe^replaced.

^Ine cracks may develop In the fins of the eirc chute sides,
to be ejected with ceramic materials when subjected to
fgh heat of an arc and may be disregarded unless they are
^and present a possibility of fin sections brestklng completely
off.

Small broken corners on the exhaust end of the arc chute

w^ll not Interfere with Its performance and can also be disre
garded.
The cup bearing and the contact ring at the hinge point of the
contact blade should be disassembled. Inspected, cleaned, and relubrlcated with G-E contact lubricant D50H47. The contact ring
should be Inspected for wear and replaced when reduced In thick

ness to less than 1/32".
17

OEI-88761

C. Every 20,000 Operations or Approximately Every Five Years - Whlct^
ever Conies First

1. At this time the breaker should be given a general overhaul)
all excessively worn parts in both the mechanism and breaks
placed. Such wear will usually be indicated when the bresdcer
cannot be adjusted to instruction book tolerances.

This overhaul

and inspection is more detailed and will require disa^embl^ of
mechanism and breaker operating parts.
2.

All roller and needle bearings in the operating mecl

be disassembled, cleaned, and repacked with G-E J/fH

«m

mnt

should

D50H15

as described under LIJBRICATION.
sassembled
3. The stationary primary contact fingers should
ntefit^aAd contact supand the silver-plated pivot area of the con'

port cleaned and lubricated with 0-E lubri qto^50H47.

4. The breaker and operating mechanism shoi

cribed for every 2,000 operations anc"

serviced as des-

adJusted before

being put back into service.

2. Magne-blast breakers applied to repetit
switching should be serviced and mainta:
recommendations, and in addition, shou
repeated at ^00 operation intervals.

ation such as capacitor
cording to the preceeding
items lAl, 1A2, and 1A3

/Double shooting

Failure of a breaker to operate
general classes; failure to trip,
ing springs will not recharge,
outline showing particular type
together with suggestions for

ly will generally fall within four
e to close or latch closed, closrheating. The following is a brief
istress that inlght be encountered,
ing the trouble:

Pailvtre to Trip

ng caused by lack of lubrication,

1. Mechanism binding or
REMEDY:

2. Mechanism binding
REMEDY:

mechanism.

lubricate

Check a

devices, etc.
latch and ro

3. Damaged tri;
remedy:
Repl

Peking caused by being out of adjustment,
ianism adjustments, latches, stops, auxiliary
>rdance with section on ADJUSTMENTS.
races for corrosion.

Examine

damaged coil.

4. Blown fuse in trip circuit.
REMEDY:4. Replace blown fuse after determining cause of failure.
5. Pau

nections in trip circuit.
Repair broken or loose wires and see that all binding screws
ed or dirty contacts in trip circuit.
Y:
Recondition or replace contacts.

GEI-8871
Failtire to Close or Latch Closed

1. Mechanism binding or sticking caused by lack of lubrication.
REMEDY: Lubricate complete mechanism.

2. Mechanism binding or sticking caused by being out of adjustment.

REMEDY:

Check all mechanism adjustments^ latches, stops, at^llary de

vices, etc.. In accordance with section on ADJUSTMENTS^^ Exslmlne latch

and roller surfaces for corrosion.

3. Damaged or dirty contacts In control circuit Inclw
R01EDY:

itrol relay.

Recondition or replace contacts.

4. Damaged spring release coll.
REMEDY:

Replace damaged coll.

5. Defective latch-checklng switch, or Interlo

REMEDY:

Replace defective switch.

6. Blown fuse In closing circuit.
REMEDY: Replace blown fuse after detez

Rg cause of failure.

7* Faulty connections In closing clrc\

REMEDY:

Repair broken or loose wl]

Id see that all binding screws

are tight.

8. Insufficient control voltage ca|^|^y excessive drop In leads.

REMEDY: Install larger wlrj>^nc^||mprove electrical contact at connectlons.

9. Insufficient control volta^|^^sed by poor regulation (a-c control).
REMEDY:

Install larger ail|£^l transformer.

Failure to Recharge gprly* 1^
1. Defective motor cut^'l^^^lMfirltch, Interlock switch, or closing latch
monitoring switch..

REMEDY:

Replace"

2. Damaged or dlrt^cd^acts In control circuit.
RMEDY: Recon^^^n or replace contacts.

3. Blown fusifcjA^^slng circuit.

REMEDY:VRepl^ce blown fuse after determining cause of failure.
4. Faulty^)m:i|(ctlon In charging circuit.

REMEDY: il^alr broken or loose wires and see that all binding screws
are tight.

1.^ras^condltlon of contacts due to lack of attention after severe duty
VOT^oo frequent operation.

DY:

Recondition or replace burned and pitted contacts.

(Contacts^,^

lould be reconditioned very carefully and only when absolutely neces/

sary.)

GEI-88761

r^2. Contacts not properly aligned or adjusted.
REMEDST:

©Etfs. _

Check all adjustments in accordance with section on ADJUSl

3. Breaker kept closed or open for too long a period.
REMEDY: Operate breaker more often to wipe contacts clean,
contacts i f necessary.

4. Overloading.
REMEDY: Replace breaker with one of adequate rating for
future loadj or re-arrange circuits so as to remove ei

5. Primeu'y connections of inadequate capacity.

REM)DY: Increase size Or number of conductors or raTO«^:xcess

current.

6. Loose connections or terminal connectors.
REMEDY: Tighten.

7. Ambient temperature too high.
REMEDY:
Relocate in a cooler place or

.£^^^e means of cooling.

REPAIR AND REPLACEMENT

The following information covers in deta
various parts of the breaker in order to
section includes only those repairs tha
on parts of the breaker that are most

^ TANT: UPON COMPLETION OP ANY REPAIR
^JUSTMENTS MUST BE CHECKED. Refer

froper method of removing
Iny necessary repairs.
it to damage or wear.

bction on INSTALLATION, paying
d

Arc Chute (To inspect or

out coils)

(7)> Fig. (7).

Loosen the

the one lower support bol4^

plete arc chute assembly
breaker, i t can be removi

To disassemble the ar^ieiil

proceed as follows: ^ 4

IMPOR-

-ALL BREAKER AND MECHANISM AD-

particular attention to ADJUSTME

To remove an arc chute^ first

This

:>e made at the installation

FINAL INSPECTION.

he breaker and remove the box barrier

supporting bolts (2) Fig. (19) and
ing a 3/4" wrench.

By raising the com-

and sliding it toward the rear of the
shown in Fig. 19*
after i t has been removed from the breaker.

1. Remove the capsassembly bolts (7> 9> 11« and 13)> Fig. 16.
2. Remove the.

*ace (5) and pole pieces (3 and 17)j Fig. 16.

3. To remove mSiroer mounting support (10), Fig. l6 remove the assembly
bolt (1), F^^6 and connection bolt (2), Fig. 18.

4. Remove the assembly bolts (16), Fig. 16 to remove the lower brace (8).
5. Rem

he lower mounting support (l4). Fig. 16 by removing the assemB (15) and the connection nut (9)> Fig. 18.

is point the side shields (12), Fig. 16, the upper arc inmner
bly (4), Pig. i8 and lower arc runner assembly (7) can be removed.

GEI-88761^
7. Further disassembly of both the upper and lower arc runner assemb^^ti

can be done by removing the various screws and 1/^" assembly hon^Cnoi ^
Illustrated) as shown In Pig. 17.

8. The arc chute sides (7) Fig. 17 can be separated by removal A^aJsemblv
bolts (2 and 4), Fig. l6.
Reassemble the arc chute In the reverse order.
be noted during reassembly:

The following Itlems should

1. Equally space the fins of the arc chute sides before^>lichg together.
Fig. 21.

2. Check to Insure that electrical connections to tMI^Uvwout colls are
tight.

3. When reassembling the arc runner assemblles«^nll|i^ that the spacers (l
and 13), Fig. 17 are correctly Installed.

4. Before bolting the upper mounting suppqgt tw^ace, make certain that
the upper arc runner assembly Is tight

the arc chute side so

that the gap between the upper Insuljji^or^^), Fig. 17* and the arc
chute side (7) Is a minimum.

5. Hake certain that the electrical ccnn%01ons (2 and 9)« Fig. 18 eo'e
tight.

To reassemble the arc chute to tha^^^er proceed as follows:
1. Rest the lower mounting si^^Pup (10) on the arc chute mounting bracket
(8) as shown In Fig. 19.

2. Slide the arc chute forwafi^Vi^ lift It slightly to engage the support

ing bolts (2), Fig. 19^aLn%j/Le slots of the upper mounting support (3).
closes the
3. Check the spring bat^ll^n.)
bati|j^^^) Fig. 22, to assure that It closes
the gap
between the upper
r

support (4), FlgJ

Jjpi^^tlon (lo). Fig. l6, and the back of the contact
and oH designs only)

4. Tighten the supi|S!'Mjl^ bolts (2 and 9)» Fig. 19. These bolts serve as

both the electra^Jand mechanical connections between the bushing and
the arc runnei^^^

5. Check thatNujCilvable arcing contact (5), Fig. 19, passes through the
slot orMew^n the probes on the upper arc runner (5), Fig. I8, v.'lth-

out toi^j^g.
Contacts

Open the breaker and remoVe the box barrier and arc chutes as previously

descr^^ed. ^To remove the contacts, proceed as follows:
nary Arcing Contacts (10), Fig. 22.

sconnect the contact braids from contact fingers by removing two

bolts (8), Fig. 22.

GEI-88761
2. Grasp the lower end of the contact fingers with pliers and pull
tact assembly downward to remove from stud assembly.

3. To disassemble braids from stud assembly, remove one bolt (5)v J
4. To disassemble stud assembly from contact support, remove two bolts
(6).
♦

5. Reassemble in the reverse order.

^ WO

B. Stationary Primary Contacts {9)» Fig* 23
1. Compress the contact spring (6).

2. Remove spring and spring guide (l).

3. Raise the contact finger to clear the primar^^o^act stop plate (8)
and lift the finger out of contact support^i^% Remove one contact
finger at a time.

a. f / r

To replace the Stationary Primary Conta^jSj^^V
1. Apply a thin coating of D50H47 greaW^ol^the hinged edge of the fin
ger (9) then place it on the contacpw^j^ort (7) so that it is re
tained by stop plate (8).

2. Open spring con^ressor (3) an^elspffile spring guide, spring and
spring compressor (Pig. 23AV^j

3. Turn nut (2) In clockwise 4^^^ion to compress contact spring (Fig.
23B) .

Hold spring firmly fwwOTe on spring compressor to prevent

spring from slipping out^ny^ compressor.

4. Place washer (not showj^ op^uide on top of spring, place top of
guide into hole in
(^)
round end of spring
guide in cutout in nra^Py finger (Fig. 23C).
3. Hold spring asseinlkr%irmly in place and remove spring compressor.
C. ^{ovable Arcing Confec«(7)# Fig. 24

1. Remove th^^i^i^y bolts (8).
2. ReassenA^^n^everse order.
D. Movable PjpM^yContacts (5)^ Fig. 24

(All 1200 Am^Breakers Ss 2000 Amp -7 Breakers)

1. Remove tiae nuts from assembly bolts (6).

2. R^|0^ the primary contacts.

3.^eJBsemble in reverse order.
^ Amp -6 Breakers).
Remove the nuts from assembly bolts (6).

GEI-88'i

2. Remove the connection bar (9) •
3. Remove the cup bearing (3).

4. Spread the contact arms (4) and zemove the primary contac€%*f5).
5. Reassemble In the reverse order.

E. Contact Blade Assembly (4, 5, 7) Fig. 24

1. Remove the connection bar (9).
2. Remove the cup bearing (3) and the pin (11).

3. When reassembling^ first Insert the plston^mhgg^ly
l^ly (10) ^ Into the
booster cylinder and reassemble the cup b|

(3).

4. Replace pin (11), and connection bar (

F. After disassembly and reassembly of anj^^ilufcts, check all contact ad
justments as described under ADJUST^
Bushings

IMPORTANT:

DO NOT REM3VE ALL SIX BUSKNGS AT ONCE.

The bushings have been

carefully aligned with the b r e a k e r d u r i n g assembly at the factory,

and It Is Important that this al^vniw be maintained to facilitate lnsta;w

latlon of the breaker In the n^n-dMa unit. It lai, therefore, recomnenc ^
Also, before
removing any one bushing, melk^l^the distance from that particular bushing
to adjacent bushings In both^j^ieeOTlons,
_
so that It may be reinstalled In

that the bushings be removed ifcflireassembled one at a time.
the same location.

It Is also possible to re^v^^nd reassemble three bushings at one time.

If this Is preferred, %ljKnii]Jnt of the bushings may be accomplished by
placing the breaker l^lS^^nerglzed spare metal-clad unit before tight
ening the bushing

bolts.

This must be done before the arc chutes

are reinstalled.

To replace the bua^nj, proceed as follows:

Rear Bushing^

1. Open tl^^eSl^er and remove the box barrier and arc chutes as already
descrlfe^ >

2. Remove th^^pper and lower horizontal barriers (l8 and 20), Pig. 7.
3. Reinove iMie four bolts at the mounting flange of the rear bushing being

renbved and lower the bushing assembly.

rrlng to Fig. 23 disassemble the primary contact springs (6) as
rSVlously described.

Msassemble the spring retainer (4) by removing mounting bolts (3).

GEI-88761

6. Referring to Pig. 22, disassemble the contact support (4) and arc
chute mounting bracket (2) by removing two bolts (3).
7. Reassemble In the reverse order. The arc chute mounting bracke
Is not symmetrical and must be assembled correctly to orient th

chute properly on the breaker.

raBIcThe longest projection of the brS

et should be toward the lower end of the bushing.
♦

Front Bushing

1. Open the breaker and remove the box barrier and arc chuli^en al
ready described.

2. Remove the upper and lower horizontal barriers (18 teASlO) Pig. 7.

3. Remove the connection bar (9)* Pig. 24, cup bea^^n^o)'
4. Remove the foiu* bolts at the mounting flangei^K^e front bushing
being removed, and lower the bushing.

3. When reassembling, first mount the busUag^^v assemble the cup

bearing (3) contact arm (4), and repla^^gl#(11). The contact sur
faces at the hinge point of the contagH^K^e and bushing should

have a thin coating of D50H47 grease
6. Check all contact adjustments as

under ADJUSTMENTS.

INTERLOCK SWITCH

To remove the Interlock switch

10 remove the two mounting

screws and disconnect the leadJi^^. Reassemble In the reverse order

and check the switch adjustmep^y^ explained under ADJUSTMENTS.

"iff

LATCH CHECKING SWITCH

To remove the latch chec^nQ^wltch (7)4 Pig. 10 (when furnished), re
move the two mounting

and disconnect the lead wires.

Reassemble

In the reverse order aml^mck the switch adjustments as e:^lained un

der ADJUSTMENTS.

MOTOR. RELAY and XJffijCTWITCHES

The three swJ^^l^are mounted In tandem as shown In Pig. (6).
1. Remove tm^nen^g spring per Instructions below.
2. Remove (2) movintlng bolts (14) from switch bracket (13) •

3. Remove the^(2) mounting screws of the lower switch.
4. Rem^B^he (2) mounting screws of the center switch.
/

3. jtegove the (2) mounting screws of the upper switch.

6^Mbconnect the lead wires of switch to be replaced.
^jL^eassemble In the reverse order and check switch adjustment as
^

explained under ADJUSTMENTS.

gei-8876:

TRIP SHAFT AND LATCH

1. Remove latch checking switch arm (10) Fig. 11 (when suppli^
2. Remove cotter pins on both ends of the shaft (12).
3. Remove set screw in latch (11).

4. Remove trip coil linkage bolt (6).

sfo

5' Place a block between the latch and frame (eitheBM^Il^) and drive
shaft until the latch is free of the key.

6. Remove key and all burrs that may be raised ^rouM the keyway on
the shaft. Burrs will scar or shave the Tefloi^jfearing surfaces if
they are not removed.

7. Reassemble the parts in the reverse ordeA^^ sure the latch spring

3h iigLm^akd
sli
is properly installed and the latch
in the center of the
latch roller. Check latch adJustmentOl^Qliescribed
nent^^l
under ADJUSTMENTS.

TRIP LATCH ROLLER BEARING

1. Remove (2) cotter pins at ends o^CTQ^t (8) Fig. 12.

l^ie •of frame until latch roller
2. Partially remove shaft out riglA^^e
(6) is free.

3. Reassemble in reverse or<^r^ith proper spacing of washers. Be

ii^e

sure latch roller rotatdl^iaely.

CLOSING LATCH

1. Remove cotter pins £«D«jCn ends of latch shaft (19) Fig. 6.
2. Remove spring andipal^lfe (l6) Fig. 6.
3. Remove set scr^K^^om latch (3) Fig. (6).
4. Move shaft (1^ y left (away from frame) by tapping lightly on the
inside endyfl>s!!aft. Rotate shaft and continue tapping until shaft

is free^A|^ will push outside needle bearing from housing.
3. Reas^mb^e^m reverse order putting bearing into frame last. Use a
smaliL^|re<^ of tubing or pipe tdien inserting bearing to assure pro
per an^^nt.

6. Check^atch adjustments as described under ADJUSTMENTS.
SUPPORT

remove motor support (8) Fig. (15) first remove the latch spring
6) Fig. (6).

GEI-88761

2. Remove the retaining ring (9) Pig. (15) and link (10).

.174582
)6174582
^006174562

0-015
0-002
0-010
0-014

006275070 0-002
0456AO866 P-005

0161A4231 P-001
0137A9252 P-001

0-010
0-014
0-001
0-002
0-001
0-015
0-002
0-010
0-014
0-002
P-005
P-006

0161A4231 P-001

0137A9252 P-001

0161A4241 P-001

0161a4241 p-001

0161A5909 P-001

016IA5909 P-OOl

relays required on special control circuits.

•2

Finger Spring
Finger
Finger
Finger

Finger

Contact
Contact
Contact
Contact
Contact
Contact
Contact
Movable Arcing Contact
Movable Arcing Contact
Tube and Piston Assembly
Tube and Piston Assembly
Motor
48 V-dc
Motor
110 & 125 V-dc & 115 V-ac
Motor
220 6 250 V-dc & 230 V-ac
48 V-dc
Relay
110 it 125 V-dc
Relay
220 it 250 V-dc
Relay
Relay
115 V-ac
Relay
230 V-ac
Potential Trip Coil - 110 & 125 V-dc
Potential Trip Coil - 220 V-de
Potential Trip Coil - 250 V-de
Potential Trip Coil - 115 V-ac
Potential Trip Coil - 230 V-ac
24 V-do
Potential Trip Coil 48 V-dc
Potential Trip Coil Spring Release Coil - 110 it 125 V-dc
Spring Release Coil - 220 V-dc
Spring Release Coil - 250 V-dc
Spring Release Coil - 115 V-ac
Spring Release Coil - 130 V.
Spring Release Coil - 48 V. dc
Switch, Hormally Open
Switch, Hormally Closed
Auxiliary Switch
Closing Latch Spring
Prop Spring
Driving Pawl Spring
Latching Pawl Spring
Movable
Movable
Movable
Movable
Movable
Movable

0137A9164 P-004
0137A9164 P-004

0-010

insulation

Lowe

••

006Mm58B|#-002

(Right)

(Left)

Throat B

0137A9164 P-003

0137A757#F^
0137A75(LP-04t
O06lW8^^01
00617^112 0^15

Cap)

Hasher (Poiv

Throat Insmaj

0137A9164 P-003

All

All
All
All
All
All
All
Ai:
a:

Ho.

0121A5964 p-001
0121A5964
023600791 P-008
023600791 P-008

Req'd

0121A5964 P-001
006509787 P-001

••

breakers whlch^ry

Primary
Primary
Primary
Primary
Primary
Primary

Check breaker and connection diagram,

iah 0161A4241 P-001 for breakers not having closing spring discharge mechanism,

except breakers with "B" in suffix.

GEI-88r

%
I

p?nW5?

Pnhftj

Pig. 1
Left Si
Operating U

ir
1. Secondary i^lqiCer

2. Inter^cl

Fig. 2 Front View ML-13
Operating Mechanism

ML-13

#i|tches

1. Trip Coil
2. Open - Close Indicator
3. Auxiliary Switch

3. Auxilflte^ ^tch
4. LatjR cnlli ^ing Switch

5. Ch®g*Dl,5 charge Indicator

5. Trip Latch

Counter

6. PoweiQsjptches

6. Charge-Discharge Indicator

7. ClosiHr Springs

8. Motor

8. Motor
9. Fuse

9. Fus^

lOf^losing Latch Roller

Ih^Closing Latch

iJ.2W5witch Cam

Close Button

10. Prop Spring
11. Trip Lever

QEI-88761

oQ-^;y7"'^•'N-'Tv: •

.o^
mdi

Fig.

ide ViewHA»5

3
Right Side Vie
Operating Mechani
>Iechani^^^

1. Latching Pawls ^

srlfck Coller
2. Positive Interl^k

3.
5.
6.
7.
8.

Ratchet Wheel^^^
f F\
Fuse
\y^y
Closing^pr^it
Main Sl^j/fie^ing
Cam ShaW^^r

4. Eccentric

9 • Opening S^lEng

10.

Guide Block

11. Lower Spji-ing Pin
12. Upjter Spring Pin

Pig.

Spring Blocking Device

Motor

Button

3.
4.
5.
6.
7.

Fuse
Spring Blocking Device
Driving Pawl
Eccentric
Closing Spring

8. Manual Charging Wrench
9- Support Bolts
10. Charge-Discharge Indicator

cr
114C5320

Sectional Side

1. Handle

2. Trip Coil Support
3. Trip Coil

Opening Spring

Mechanism

. Trip Latch Roller Support
. Crank Shaft
12. Cranks

18. Stop Plate
19. Spring Rod
20. Spring
21. Spring

4. Trip Armature

13. Prop Pin

5. Prop Reset Spri:

14. Prop

22.

15. Drive Shaft

23. Stop Pin

16. Cam
17. Check Nut

25. Cam Sheift Bearing

Cam Follower

7. Trip Shaft

8. Trip Latch

Guide

24. Main Sheift Bearing

9. Trip Latch Roll

H
I

OD
ON
U)
U)

GEI-88761

Switch Cam

2. Closing Latch Roller

3. Closing Latch

4. Latch Adjusting Screw y
5. Spring Release Solenoid

6. Control Relay
7. Latch Checking Switch ♦

8. Switch Striker ^

9. Charge-Discha^^^^
Indicator

10. Power Switchj«|^V

11. Latch Monitc^jjnVSwitch

12.

Motor

13. Fuse

14. Switch SipWt
iLig|iQ#t Bolts
Bolts

mSiDort
15. SwitchreiSlBort

^atch Spring
16. Closto^^atch
17. Reldsn^joil
l^oil Bolts
^Coil Support
: Latch Shaft

Mounting Bracket

Fig. 6

Control Mechanism

rimal^ Contact Wipe

Prii

Fig. 8

Arcing Contact Wipe
Contact Adjustments

Stationary Primary Contacts

Z. Movable Primary Contacts
3. Buffer Block

4. Stationary Arcing
Contacts

5. Movable Arcing "ontacts
6. Contact Arm

GEI-8

o\
00
KD
0
CO
m
01

action of Breaker Pole Unit

16. Frame
17. Operating Crank

Box Barrier

Blow-out Co
Blow-out C

18. Upper Horizonted Barrier
19• Spring Retainer

Arc Runnt:
Pole Pi
Stati
Bo:
An

20. Lower Horizontal Barrier

cing Contact

21. Operating Rod
22. Stationary Primary Contacts

23. Movable Primary Contacts

Po3fe#Piflfee

24. Cup Bearing

Arc
Blow-out Coil

25. Yoke

Blow-out Core

Lower Barrier

^Front Bushings
tear Bushings

26.
27.
28.
29.
30.

Movable Contact Arm Assembly
Movable Arcing Contact
Booster Tube
Connection Bar
Booster Cylinder and Piston

OEI-88761

EL
pn ^

Pig. 9
Adjustable Coupling for
Primary Contact Wipe Adjustme

1.
2.
3.
4.

Operating Rod
Operating Rod Pin
Adjusting Nut
Check Nut

Fig. 10

5. Stations^
6. Movablg^ Pi

Ipiiry Contacts
7y Contacts

7. Contadfeta
8. YokeW^

Positive Interlock Switch

X. Positive Interlock Shaft
*2. Switch Arm
3. Interlock Switch

4. Switch Support
5. Auxiliary Switch

6. Switch Support
7. Latch Checking Switch
8. Switch Arm

9. Trip Shaft

GEI-887

Trip Coll Support
Trip Coil
Mounting Bolts

iMi

Counter

Trip Latch
Trip Arm Screw
Manual Trip Lever
Open-Close Indicator
Auxiliary Switch
Switch Arm
Latch Set Screw
Cotter Pin

Prop Spring

I
. 11

Auxiliary Switch and

Trip Coil

1. Switch Support^^^
2. Latch Checking^w^
3. Switch Arm

4. Trip Latch
5. Reset Pin

6. Latch Roll^g J

7. Latch RoESe^^nk

8. Latclk^RC/ef Pin

Pig. 12

Latch Checking
Switch

QEI-88761

m nJc-J
1. Plunger
2.

Washer

3. Breaker Llfl^t^iai:

•y

Ms,
A m

Fig. 13

Plunger Interlock

•/
1. Actuating Crank
2.

Link

3. Tripping Crank
4. Turnbuckle
5. Spring Release Crank

; 11

g. 14 Spring Release Interlock

GEI-8W^

c?
Pig. 15

Driving Elemej

1. Mounting Bolts
2.

jm^lng Ring

Eccentric

kor Support
jrainlng Ring

3. Hex Charging Stud
4. Fuse
5. Manual Close Button

?iving Link

1. Assembly Bolts and
Bushing
2. Assembly Bolts
3. Upper Pole Piece

4. Assembly Bolt
II
1-4

cvi

5«
7.
8.
9.
10.
11.
12.
13.

Side Brace
Assembly Bolt
Lower Brace
Assembly Bolt
Upper Mounting Support
Insulating Cap
Side Shield
Assembly Bolt

•'7 14. Lower Mounting Support

Fig. 16

Arc Chute Assembly

15. Assembly Bolts
16. Assembly Bolts
17. Lower Pole Piece

18. Upper Insulation

GEI-88761

1. ypper Arc Runner Spacers

2. Upper Arc Runner Assembly

3. Blowout Core

4. Blowout Coll
5. Insulation

♦

6. Upper Arc Runner

7. Arc Chute Side

8. Upper Insulatl(^

9. Lower Arc Runne^^«X
10. Blowout Coll

11. Blowout Core \ My

12. Lower Arc Rulue^flssembly

13. Lower Coll^onWctlon
14. Lower Ar^^o^lSr Spacers
13• Lower St^^xly
16. Upper Iri^
iM^latlon
17*
17 • Lower^nu^atlon
Lower

Fig. 17

Arc Chute Assembly

with Side Removed

vll^pper Mounting Support

^ Connection
Bolt
f 2|
Coi

Upper
Up]
Blowout Coll

Fig. 18

Front View

Arc Chute Assembly

•4.

Upper Arc Runner Assembly

5.
6.
7.
8.
9.
10.

Upper Arc Runner
Side Shield
Lower Arc Runner Assembly
Lower Coll Connection
Connection Nut
Lower Mounting Support

GEI-887|^^

-• • I'l •'

^rrri

Fig. 19 Arc Chil
Accesslb^

^
2. Supportk^',^oJb

fertlally Removed Showing
of Arcing Contacts

6. Assembly Bolts

1. Rear Bushl

3. Upper Mailii^Hg

5, Station*^
5.

Support

*rclng

7. Brace for Arc Chute

o. Arc Chute Mounting Bracket
9- Lower Supporting Bolt

Contal^l^^embly

10. Lower Mounting Support

4ova>te>

11. Upper Horizontal Barriers

clnR Contact

<&•
m

Fig. 21

Arc Chute Fin Spacing

GEL-88761

PART

Sleeve Bearings -

links, trip

shaft, etc. (Teflon coated
besirings)
Sleeve Bearings - main crank
shaft, driving pawl lever,

(Bron^q or cast iron).

LUBRICATION AT
MAINTENANCE
PERIOD

ALTERNATE LUBRI

No lubrication

No lubri

n required.

required.

Light applica
tion of machine
o i l SAE 20 or

SAE 30.

Contact Arm Hinge Assembly
C\;q) bearing
Loose rings between bushing

(REQUIRES DISA;

No lubrical

required.

earings or link^
er instructions

ply D50H15 lubriliberally.
ipe clean and apply

D50H47.

and contact arm.

Roller and Needle Bearings

LightM|^9iica-

tipimgil^feLachine
'20 or

Clean per instructions
and repack with D50H13
lubriceuit.

30.

Ground surfaces such as cams,
ratchet teeth, etc.

(Surfaces coated with f^S2)i

lubrication

Wipe clean and
apply D50H15

Ground surfaces such as
latches, rollers, pro;

No lubrication required.

required.

Wipe clean and apply
D50H15 lubricant.

lubricant.

Silver plated cont
primary disconnec

Wipe clean and

apply D50H47.

Booster Cyl

Arcing Contac^ps

D50H47.

Do not
Lubricate.

Do not lubricate.

Do not

Do not lubricate.

Lubricate.

Fig. 20

Wipe clean and apply

LUBRICATION CHART

GEI-8876

GEI-88761

Fig. 22 Rear Bushing AssembJ^^^
1. Rear Bushing
^ %
2. Guide and Support^fdt A^
As
Chute

3. Bolts for Contact^uJSort

Fig. 24

Removal of Contacts

1. Contact Springs
2. Stationary Primary
Contacts

4 . Contact Supporlj^J^^

3. Cup Bearing
4. Contact Arm
5. Movable Primary Contacts

6. Mounting Boltf

6. Assembly Bolts

5. Bolt for Flexm^pald
4

7. Flexible Brajd^y
6. Connectlonffid9±

9. Stud foi^lo^Q^ng Arcing
Plngedl
10. Stat^^^^y^lrclng
7clng Contact
Contact
Assenra^ ^

11. Spring sfcjffle
12. Insulating Plate

7. Movable Arcing Contact

8. Assembly Bolts
9. Connection Bar
10. Piston Assembly

11. Hinge Pin
12. Buffer

GENERAL BfCTRIC SALES OFFICES

* tftRMlflol iMlPfRRRt (MclllEJfif Apant
and Ohtfibirtm) Soln

t ilnctfk Iftm^ Eqidpnwit Solna

• 11

•I

.2131 KIghlond Ava.

Mwanln tSOIZ

3330 N^Cantrol Ava.

Bohimero 21201.

Radweed Clly 74043 ...

• t

tecfootanta 73S16

MISSISSIPPI

Karadan 0431B
.. 2703.2721 DixwaU Ava.
Harlferd 04103...—
7M Aaylum Ava.

Carol GeUaa 33144
JackaenvHa 32202

1323 IL Allmttc Ava.
2S0 Bird Road
.1701 Hdl Sl.

Miamt 33134.

4100 Waal Flaglar Sl.

t
1T

fanaocala 32503
Firal BocutUdg.
Tampa 33407... Nandaraan Blvd. ql loH Ava.
Tampa 33407..
2104 S. Lola Ava.
1040 Paadnraa Rd, N.W.

402 Charry Sl

• t
IDAHO
•1
Belaa S3704
ILLINOIS

3002 Pauban Sl.

1S24 htohe Sl.

• t i l Chicago 40400...
• t

Paeria 41403

•

Racklard 41103

040 S. Canal SL

. ..2000 N.E. Parry Ava.

• t }

Evanivilla 47714

Fart Wayna 44807.
Fart Wayna 44004...
Indlonepelia 44207.

•TT

*t
t

* 11

• t

I PiltrburM 132BS.
York 17403

.733

54 /THarrt
Harrtton

Columbia T

Graanvllig.

'79601

If ChrHti 71^1........ 205 N. Cheporrel

Oelfes 7S307

• t S

VUMONT

Eaal Oranga 07017 .......

i ASMtny 12203

i Ave.

. t
Binghmtan 13702
• 11
Bullalo 14302
*t I Haw Ycrk 10022

419 S. Mabi Avo.

Rochaalar 14404.
Syrocuaa 13204.

nlnMon Ave.
eoti Ave.

Jontet Sl
:.1001 Srood SL
.Pea Box 308

Ulico 1351^

..139 W. Trede Sl
.801 Svmmit Ave.
14 W. Merlin SL

1433 Broadwoy

3404 S. Calhaun Sl.
3730 N. Meridian St.

418 Rosier Ave.

430 N. Michigaa Sl.

2858 W. Merkel Si.

515 Third St.g N.W.

2421 Victory Pkwy.

, -1204

'44104

. ..4966 Woedlend Ave.
43215. ...
395 f. Brood Sl.

43213
...937 Oorrel Ave.
.11 W. Monumenl Ave.
ion 45402
..110 Wa Firsl St.
iilield 44904....... ...544 Rork Ave- West

.3125 Oeugiot Rd.
273 B. Indlen^o Ave.

Youngstewn 44507.

200 S. Moin St.

Rutlond

SB'A Center Sl.

VIRGINIA

- ^ Bngo Sl.

Delovrore Ave.

Wavarly

"—'—
...2300 Ateodow

215 N. Stonten St.
40B W. Seventh St.
Richmond Ave.
500 8. 50th SL
123 North N St.

I 5dt leke aty 64110

Albuguarqua 07100 120

NEW YORK

0101 Sltmrnons Freevrgy

B Rose 79901
Fort Worth 76(02
Koutton
lubbeck 79400
Midland..
Son Antonio 78304

NEW iSRSEY

•It
• TT

.........13B5 Colder Ave.

UTAH

NEW MEXICO

• t

443 Cedcr Sl.
403 AmeflRo Blvd.

oumont 77701

407 S.

Mmichaalar 03104

• t

.....832 Ceorglo Ave.
322 Commerce St.
301 Hennoh Ave.4 NaW.
.....1420 Union Ave.
R.Oa Son 1040
1717 W. End Sldg.
253 Main St.g Eoct

XRWiB 79101

Laa Vagaa 07104..

St.

.1310 lody St.
W. WosMngton Sl.

i t I ChatloRoosa
Kingtp

...103 N. Wyandng^

• t
0«na 37701
NEBRASKA
• t
Omoha 40102
NEVADA

Ed.

SOUTH CAROLINA

* t

303 K Braadwg

BOItnga 37101

. 020 I. tftdianopoliE

LeuhvIUa 40210. ..

.104 W. Faurlaanth Sl.
1013 Locual Sl

[ton 45402.......

K^HTU«Y i^n

3 Pann Cmlar Plaao

Pillaburgh 13923 .The OBvar Rtdt.MaHan So.

212Vb W. Firih St.

T
Sl. louia 43101
MONTANA

210 Sacand St., SB.
Davanporl S2S03
...........1037 Slola Sl. Baltandarf. lavra
Oaa Mebiaa 30310
3037 Maria Kay Rd.
Slaux aty 31101...
320 Piarca Sl.
Wkhlla 47211

041 Odk Sl

Jehiutavm 13702

11 i Philcidatphia 17103

P.O. Box 33

lepbi 44002 .
Kaniai City 44103

KANSAS

* t

........210 S. Lamar St.

..2707 Waahingtan Ava.

South Band 44401.
IOWA
Cadar Ropida 32401
• t

2727 N.

PENNSYLVAIDA
* 1
ARmavm 1BI02....
Eria 14301.

12 S. Sixth SL

INDIANA

•t*
.**1

Portland ^210

14 W. Supartor SL

Callperl 37302

4223 Eoat Slala St.
.407 E. Adama Sl.

Sprkigllald 42701.

Madlerd 77301

104 E. Waahingtan SI.

NEW HAMPSHIRE

GEORGIA

AHanla 30307.

314U| W. Court Sl.

Fargua FaUi 3M37.
Minnaopalia 33402

• 11

777-14ih Sl, N.W.

Mocan 31202
Savannah 31403

Eugana 97401

• t

210 W. Franklin SI.
727 S. Burdkk Sl.

t
Jacktan 37201
MISSOURI

201 Unlvarally Blvd.

I Cacao Baach (Copa Conavaral Oflica)

• 11

• t

* 11

Lenalng 40701... 301 Bank el Leniing BIdg.

I Waahkiglon 20003..

2000 Claaaan Blv
74114
Calufflhta BIdg.

OREGON

Saginavr 40407 Sacand Nalland Bank BIdg.

t
II

FLORIDA

• 1

2133 Sa. fifai Sl.

700 Anialnalla Sl.

Jackaen 47201
Kolamaiea

MINNESOTA
I
Dululh 33002

DISTRICT OF COLUMBIA

• t

Tdaa

120 Mapla St.

2BS Orava Sl.

Grand Re^a 47304 2021 Madiaon Ava.« S.E.

407 Thirtaanib SI.
33 Vatarona Blvd.
2407 "J" SI.
2340 riral Ava.

CONNECTICUT

*t
• 11

31 Sl. Jomaa Ava.

RinI 4B303...

COLORADO

• 111 Dtnvar 80201

47 Earl Franklin St

Dalroit 40202

• t i Sen Oltga 72103
• T 11 Sm Frenclaca 74104... ...233 Mantgomary SI.
San Jaaa 73I2B

Oklohama Cty 73104

MICHIOAN

3323 Wilahlta Blvd.

Oakland 74412

77 Cantral Sl

Warcaatar 01403

North UlRa Rack TZIta.
..1700 E. Waahinatim
t
Tkia BluH 71402
... p. O. Sox 1033
CALIFORNIA
..1332 N. Waal Ava.
Fraano 73720
• t I loa Angalaa 70034. .. - 213 N. VisRaa SI.

t i Ua Angaha 70003.. .

132 Slata St.

1 North Charlaa

Kogrralavm

Sprbigllald 01103..

..............

t T f Rnalon 02117

...131 S. Tucaon RWd.

•

400 Trnvia St.

MASSACMUSETTS

ARKANSAS

•

Avgwaia

ben^ 04402

. t

Tucaen RSTII

4747 Earharl BlvA

MARYLAND

...704 Ooaammanl Sl

037 CraWar Sl.

Naw Orlaona 70123

• 1

.1424 Ryan Sl.

Shrcvaparl 71101
MAINE

MobSa 3M02.
ARIZONA

433 Oak V3la Blvd.

I Naw Odaena 70112

i iSoaina and Onfanaa tayipoiant !

StmlnslicRi 3S20S.

.720 Murray Sl.

Baton Rauga 70B1S

Late Omrlaa

S Coaipanant Solaa OpaVgtian

InttrwtllMi

OKLAHOMA

LOUISIANA
Alaxondrio 71309

SAIIS OFTICf CODS KEY

• 11

Rt^wir*

, WhtR Tw Kok* HMItlcal frabltim . . . N*t4 SntlMt biletaiottaa

REAOV 10 ASSIST VOU .

8 Newport News 23601
R.O. Box I038g 311 Mobi Sl.
Richmond 23230
5001 W. Brood Sl.

Reoneko 24005

.....„..9i20 S. iefftrtoo St.

WASHINGTON
t
Rotco 99301

" t
t

.824 Wa lewis St.
... 710 Second Ave.
S. 142 Roil St.
...E. 1005 Trent St.

8 Seattle 98104.
Spokeae 99220 Spekone 99220....

WEST VIRGINIA
Chorleston 25328.. .304 MecCorkle Ave.* S.E«
* t
Fobmont 24555.....
.......310 Jacobs BIdg.
*
Wheeling ..........w... W.............40 Fourteenth St.
WISCONSIN

8 Appleteo 54910

t
* 1 t

510 W. College Ave.

Medhen 53703

340 W. Woshlnglen Ave.

Mtlweukee 53233.

CANADA:

Conodion

.940 W. Sl. Roul Ave.

Oenerol

Electric

Cempony,

Itdvg Toronto
HAWAII:

Amarkon Foctora. Lid. P.O. Rax 0100,
Henoluly ttBOl

GENERAL ELECTRIC SERVICE SHOPS
parfarmaoca of your aguipmaat. Far full kiFaraialiaa ahaat thaaa aarvkaa,
caoloaf year naoraat aarvka akap or aalaa eltka.

JP^. racaodl.
goto ovailabla day end
I year pramiaaa. lalaal
xa aaad to mahtlain peak

WHEN YOU NEED SEtva . . . ThM« M

ftwig and rtboRd fut nlMtrit epporofin.
idfhf, seven deyt o weelu fer vwk in "
foctonr wetfiedf end ^enMne 0-f reoe*

Calumbua 43223PA. Rax 6178. 212S Eakia Rd.
4360S
403 Daarbern Ava.

"^''^^Strelher) Arkonaoa City..,

Shmbishcm 3S211

Oi. Co.. P.O. Box 777

Yauagrtawrt 44307... ..273 E. Indionolo Ava.

KENTUCKY

AtiZONA

lauiivitaa 40907

(TneenUI Gltndole
•r St.

3700 Crlllandan Driva

LOUISIANA

Naw Oriaana 70117.

CAllfORNtA

Lot Angolsi
*{iot AnpHt

tanford Ave.

.itieflel Airport
OeUond 9460
Sacromento 9SI1
Son Erondtco
COLORADO
Denver S020S

3d00 Wood SI.
North 17th Sl.
1071 Korrison St.
.S3S9 Lertmer St.

Baltiroera 91230

720 f. Fart Ava.

laeh 33010
I 33MI

4ra0 ButtarmiDt HoOow Rd, RD #1.

TEXAS

Carpua Cliriiti 7B401..
-.I1S Waco Sl.
Dailoi M13S
—3101 Maner Way
Hauaian 77020
S334 Hofvay Wilaoa Orlva

MINNESOTA

lOSS—dflh Ava.. N.

MISSOURI

Konaoa City 64110

Midlond 77704

...3513 Gardnar Ava.

St. lauii 63110

grim 3J10X.
t.O. Box 2731. 2010 W. Baavar Sl.

1115 Eaat Road

Albany 111051

1077 Canlral Ava.

Buffolo 14111

*{Naw York) Un^n. K J—..

Soil Lake City a4I04...-..30l S. 7lh Waat Sl.
VIROINIA

Richmond 23114

SIB Urban St.

Roonoka

(Naw York) Narlh Bargan, N. I 07047.

,.3030 Paochlraa Indualrial Blvd.

6001

4360 W. 41lh St.

Tannalta Ava.

1731 EdiaU Ava.
1740 W. Varment St.

(Dovanpocl) BallandacI S1721.1095 Statt St.

—

Saottla 70134

—

3411 Fkal Ava, S.

'Saottia 701*'*

910 Dawtan Sl.

Spokane 9

1 Bivar Road

i. 4313 Mlaaian St.

WEST VIROINIA

NORTH CAROLINA

ft. Wayna 46B03
Indianopalia 46222

1403 Ingram Ava.

WASNtNOTON

Schnnaatady (Inairamantatien Sarvka) tlSOi

fhkega 60632

141)07

P.O. Rax 1337,1IS Ai'baTmorIa Ava, S.E.

1611 W. Ellaabalh Ava.

. (Alimto) Chemblaa 3000S

704 i. Johnatan Sl.

UTAH

NEW YORK

lOSl 0. 30th Sl.
P.O. Box IMS

.t41 Oak St.

Waal MHIIin. Pa. 13)12
YaA I7403.._
54 N. Harrlaan St.

MICHIGAN

57J0 Third Sl

660 E. Highland St.

Philadalphia 17114
.1040 E. Erie Ava.
(Pillaburgh) Hemaataad 1S110
—.

(Soalon) Madferd 03tSS...
3760 Myalk Voaay Parkway

Mtnnaapolia SS430
Ifvilis 04479
370 Alwoler Sl.

iahnalawn 1S701-

MASSACHUSETTS

Datrail 46101

..9737 KW. ITlh Ava.

Allintown 16103

MARYLAND

CONNECTICUT

(Seulhlnglen)

11IS Da Armoa St.

OUOON
Portland TniO
PENNSYLVAFHA

Chotletia 1610R

Chariaaton M310.

231S Thrill Read

306 Mo^arkla Ava.

WISCONSIN

OHIO

Oncinnoti 4S102
*Cinckmati 4S131
Oavaland 4411S

—

444 W. Thkd St.
260 W. MltchaH Ava.
4477 Eoat 47lh Sl.

GENERAL ELECTRIC COMPANY, PHILADELPHIA, PA.

Appialan S4710

—

JBidwoy Induatilol Acaa

P.O. Rax 63 County Tnink P

Milwaidcaa 33133

940 W. St. Paul Ava.

INSTRUCTIONS

AND

RECOMMENDED PARTS

FOR

MAINTENANCE

SEK-41902 C

Supersedes GEK-41902 B

MAC3NE-BL.AST CIRCUIT BREAKER

Type:
AM-4.16-250-9

1200 & 2000 Amperes
With ML-13 Mechanism

CONTENTS
INTRODUCTION

RECEIVING HANDLING And STORAGE

INSTALLATION

DESCRIPTION Of OPERATION

ADJUSTMENTS

GENERAL MAINTENANCE

RENEWAL PARTS

GENERAL^ ELECTRIC

Clreatt BrMker GEK.41902

manual close and trip levers on the breaker. All
secondary connections from the breaker to the metal

clad unit are made through the coupler (1) Fig; 2.

A spring release interlock, Fig 3, is provided
to discharge both the closli^ nnrf opening springs
when the breaker is withdrawn from or inserted

into the Metal Clad unit.

Figure 1. (8034475) Spring Blocking Device
1.
2.

Charge->Discharge Indicator
Support Bolts

Driving Pawl

Manual Close Lever

Motor

Eccentric

7.
8.

Closing Spring
Manual Charging Wrench

10.

Fuse

Spring Blocking Device

Figure 2. (8034473) Left Side View ML-13
Operating Mechanism
1.

Figure 3. (8038805) Spring Discharge Linkage
1.

Link

2.
3.
4.
5.
6.

Adjusting Bolt
Trip Latch Crank
Discharge Crank
Adjusting Clevis
Spring Release Crank

Secondary Coupler

Interlock Switches

3.
4.

Auxiliary Switch
Latch Checking Switch

Switch Cam

Charge»Discharge Indicator

Closing Latch Roller

Power Switches

9.
10.

Closing Latch
CIrving Springs

11;

Motor

12.

GEK-41902 Magne-blast Circuit Breaker

».

When the breaker is used interchangeably with

A positive interlock (3) Figure 4 and interlock
•vitch (2) Figure 2, are provided between the

type MS-13 solenoid operated breakers in M-26

or lowering of the 'breaker in the unit while in a
closed position and to prevent a closing operation

closing circuit. These breakers are identified by

or lowered position. To insure that this interlock
will function during manual, as well as during
electrical operation of the equipment, both mechan
ical and electrical blocking is provided. If for

. In cases where breakers with type ML-13
mechanisms must match and line up with breakers

'eaker and metal-clad unit to prevent raising

when the breaker is not in either the fully raised

any reason the closing springs should be dis
charged against the positive interlock the mechan

ism will be jammed and be inoperable. The
mechanism can be released and returned to the

reset position by pushing in on the trip lever (8)
Figure 5. It may require more than normal

metal-clad units, fuses (12) Figure 2, are mounted
on the breaker for protection of the motor and
a "C" or "K" suffix in the breaker nomenclature.

having type ML-11 mechanisms the spring charging
circuit for both mechanisms should be fused with
Buss Company Fusetrons as follows:
Cont. Volt.
48v
llOv
125v
I15v
220v

force to release the interlock.

A plunger interlock, Figure 14 can be provided
when required to operate a stationary auxiliary
switch and/or a rod interlock mounted in the metalclad unit.

Fuse Size

d-c
d-c
d-c
a-c
d-c

Cat. No.
FRN
FRN
FRN

10
4
4

FRN

250v d-c

FRN 2.5
FRN 2.5

230v a-c

FRN 2-5

Spring Charging

The mechanism has a high speed gear motor

(10) Figure 5, that compresses a set of closing
springs through the action of an eccentric, ratchet,

and pawl assembly. The rotary action of the motor
is converted to a straight stroke through the eccen
tric (11) Figure 4, and aleverthatcarries a spring
loaded driving pawl (3) Figure 1.

Fieure 4. (8034463) Operating
Right Side Mechamsm
View.ML-13
1.

Upper Spring Pin

Latching Pawls

Opening Spring

Cam Shaft

Ratchet Wheel

7.
8.
9.
10.

Positive Interlock Roller

Bearing Block
Driving Pawl
Lower Spring Pin
Driving Pawl Lever

11.

Eccentric

12.

Closing Spring

Figures. (8034471) Front View ML-13
Operating Mechanism
1.

Auxiliary Switch

Open - Close Indicator

3.
4.
5.
6.
7.
8.

Trip Coil
Prop Spring
Operation Co'onter
Trip Latch
Charge-Discharge Indicator
Manual Trip Lever

9.
10.

Manual Close Lever
Motor

Maene-Diast circuit tsreaicer

ed" and the driving pawl is raised from the

The pawl advances the ratchet wheel (6) Figure 4

ratchet wheel.

a few degrees each stroke where it is held in pos

ition by the latching pawls (2).

The use of the ratchet wrench

provides for maximum safety in the event
control power is suddenly restored without warning.
In this event, the motor drive will override the

When the ratchet

wheel has been rotated approximately 180 degrees

'he closing springs (12) will be fully compressed.
As the ratchet wheel continues to rotate, the spring

ratchet wrench and continues to charge the springs.

load will shift over center and attempt to discharge.
After a few degrees of rotation, the closing roller

Closing Operation

(7) Figure 2, will engage the closing latch (9) and
the compressed springs will be held by the latch
until a closing operation is required. During the
last few degrees of the ratchet wheel rotation the
power switches (8) are opened and the drivingpawl

energizing the spring release solenoid (15) Figure
6, or manually by pushing the close button (9)
Figure 5. In either method the closing latch is

raised from the ratchet wheel surface.

The breaker can be

closed electrically by

rotated from under the closing roller to release

This

the closing springs (10) Figure 2. The energy
in the springs is used to rotate a cam (16) Figure

allows the motor and driving mechanism to coast
to a natural stop expending all residual energy.

7 and close the breaker through the operatmg

mechanism linkage. During the closlr^ operation
the mechanism is trip-free at all times. The break
er is held closed by the closing prop (14) moving

During the time the springs are being com

pressed a relay (17) Figure 6, is energized to hold
the

closing

circuit open.

The relay remains

into position under the prop pin (13). During the
closing operation the opening springs (4) Figure 4,

energized until the springs are fully charged and
the control switch contacts are re-set.

are compressed and held ready for an opening
operation with the trip latch (8) Figure 7 bearing
against the trip latch roller (9).

The closing springs may be charged manually

if control voltage is lost. A 5/8" ratchet wrench
can be used to rotate the eccentric in a counter
clockwise direction until the indicator reads"Chare-

When the closing operation of the breaker is
completed and the closing latch is fully reset.

>
-r

I
• -VI

Figure 6. (8034467) Control Mechanism
Latch Checking Switch
Switch Cam
Switch Striker

Switch Support Bolts
Switch Support

Closing Latch Roller

Power Switches

Closing Latch

Closing Latch Shaft
Latch Adjusting Screw
Release Coil Bolts

Closing Latch Spring

Latch Monitoring Switch
Switch Mounting Bracket

Spring Release Solenoid
Release Coll Support
Control Relay

'=:K-.41902Magne-biast Circuit Breaker
the contacts of the latch monitoring switch closes

to permit the spring charging motor to be energiz
ed and recharge the closing springs.

As the breaker opens to internipt a current,
the arc first starts at the arcing contacts (6 It 27)

Figure 8, transfers to the arc runner (4 & 10)
and energizes the blow-out coils (3 It 11). This
action introduces a magnetic field between the
pole pieces (5 It 9) of the internmter that forces

The breaker can be opened either electrically

the arc deeper into the arc chute (8). At the time

by energizing the trip coil (3) Figure 5, or man
ually by pushing the trip lever (8). In each method

the arcing contacts part a discharge of air is

the trip latch is rotated off the trip latch roller,

the arc.

permitting the operating mechanism linkage to

collapse. The energy stored in the opening springs
is released to provide the required opening speed
for successful interruption of the circuit.

expelled through the booster tube (28) across
This air flow assists the arc transfer

and interruption by blowing the arc away from the
contacts and into the arc dstte.

The magnetic

field forces the arc deeper into the interrupter
along the diverging arc runners.

I UlULLLU •

/ ;•

\\\ W
v\\\
V

\Oj (
i^J

Fig. 7 (0114C5320) Sectional Side View of Mechanism
1.

Handle

Trip Latch Roller Support

Trip Coil Support

Crank Shaft

3.
4.

Trip Coil
Trip Armature

Cranks

"5.

Prop Reset Spring

6.
7.
8.

Cam Follower Roller
Trip Shaft
Trip Latch

Trip Latch Roller

Prop Pin
Prop
Drive Shaft

Stop Plate
Spring Rod
Spring
Spring
Spring Guide
Stop Pin

Cam

Main Shalt Bearing

Check Nut

Cam Shaft Bearing

Marne-bUst

Figure 8. (01S2CS973) Cross Section of Breaker Pole Unit
Box Barrier Support
Upper Blow-out Core
Upper Blow-out Coil

t%)er Arc Runner

Upper Pole Piece
StationaxT Arcing Contact
Box Barrier

Arc Cbute Side
Lower Pole Piece
Lower Arc Runner

11. Lower Blow-out Coll
12. Lower Blow-out Core

13.

Box Barrier Guide

21. Operating Rod
22. Stationary Primary Contacts
23. Movable Primary Contacts

14. Front Bushing
15. Rear Bushing

24. Cup Bearing

16.

26. Movable Contact Arm Assembly
27. Movable Arcing Contact

Frame

17. Main Operating Crank
16. Primary Contact Springs

25. Yoke

26. Booster Tube and Piston

29. Connection Bar
19. Spring Retainer
Lower Horizontal Barrier 30. Booster Cylinder

GEK-41902 Magne-blast Circuit Breaker

The arc chute has a series of interieaving cer

amic fins, Figure 19. As the arc is forced into the
interrupter it is lengthened in the gradually deep
ening serpentine path between the fins so that the
electrical resistance of the arc is rapidly increased
and its heat is absorbed by the ceramic material.
The increased resistance reduces the magnitude
and phase angle of the current and at an early
current zero the arc cannot re-establish itself
and interruption occurs.

Trip Free Operatioo

If the trip coil circuit is energized while the
breaker is closing, the trip armature will force

the trip latch (8) Figur e 7 away from the
the trip
trip
roller (9) causing the mechanismlinkage
m linkage to coUuse
collapse

and the breaker to re-open. The closing cam (l6)
will complete its closing stroke and the springs

will re-charge as in a normal closing operatioo.

ADJUSTMENTS
All adjustments should be checked during per
iodic inspections and whenever it becomes nec
essary to repair or replace parts that have become

worn or defective while in service. The following
adjustments are listed in the order in which they
are to be checked after removing the box barriers

MECHANISM UNLESS THE CLOSING SPRINGS ARE
BLOCKED AND THE OPENING SPRINGS HAVE
BEEN

TRIPPED

BLOCKED.

OPEN OR

MECHANICALLY

THIS MEASURE IS REQUIRED TO

PREVENT ACCIDBNTAL CLOSING OR TRIPPING.

and front cover from the breaker.
DO NOT WORK ON EITHER THE BREAKER OR

Refer to Figure 9.

ClOM the breaker until

I |l

Primary Contact Wipe

Arcing Contact Wipe

Figure 9. "-9" Contact Structure (0I32C2709)
Figure 9 Contact Adjustments
1. Stationary Primary Contacts 5. Movable Arcing Contacts
2, Movable Primary Contacts 6. Contact Arm
•3. Buffer Block
T. Throat Baffle
4.

Stationary Arcing Contacts

Maga*.

the arcing contacts

just toucm

This can be

determined with the use of a circuit continuity
tester such as a light indicator or bell set. In.

this position, thegap between the stationarypriraary
contacts (1) and the movable primary contact (2)

should be 5/16" or greater. This setting has been
made in the factory and no adjustment is provided.
A wipe of less than 5/16" is an indication that toe

arcing contacts need to be replaced. When maifing
this check, see that the movable arcing contact
passes between the probes on the upper arc runner
without touching.
On toe "-9" design, check

for clearance between the arcing contact (5) and
the slot in toe throat baffle (7) during entire

stroke of toe moving contact assembly.
Primary Contact Wipe

Refer to Figure 9, when toe breaker is closed

toe stationary primary contacts (1) should rise

GEK-41902

Primary Contact G;

Refer to Figure 10. Wtth toe breaker closed,

press toe manual trip butten allowing toe breaker

to trip open normally. Do not force toe contacts
open wider by hand. The gap between toe stationary
prxma^ contacts (5) and the movaUeprimary con
tact (6) measured betweentoe cloeestpoints, should

be 3 5/8" to 3 15/18". To change tMn gap, loosen

check nut (17) Figure 7, and turn the adjusting
nut (18) on stud (19). Screwing toe adjusting nut
down willdecreasetoeprimarycontactgap. Tighten
toe check nut and re-meaaure toe contact gap
(close and trip the breaker before checking the
measurement). Whenever the primary contact gap
is changed, the primary contact wipe should be
rechecked and, if necessary, readjusted.
WHEN WORKING ON THE MECHANISM IN THE

from 1/4" to 5/16". Before checking this dimen

CLOSED POSITION, KEEP FINGERS CLEAR OF
THE LINKAGE, AS ACCIDENTAL TRIPPING CAN

sion be

CAUSE SEVERE INJURY.

sure the

mechanism

re-set

so that

the prop pin (13) Figure 7 is resti^ on toe prop.
To obtain the proper contact adjustment, open
the breaker and, referring to Figure 10, loosen toe

check nut (4) and turn the adjusting nut (3). Screw
ing up onthe adjusting nut will decrease the primary
contact wipe, down will increase it. Tighten toe
check nut, close the breaker and recheck toe wipe.

With toe primary contact wipe correctly adjusted,
toe clearance between toe contact arm (6) Fig
ure 9 and toe buffer block (3) should be 1/16" or
greater when toe breaker is fully closed.

Trip Latch Wipe

Refer to Figure 7. The w^e of'toe trip latch
(8) on toe trip roller (9) should be from 3/16"

to 1/4". This czxx b6 mstsuwd by putting a tilni

of grease on toe latch (8), closing toe breaker
part way, and tripping. Tlie mechanism has toe
proper trip latch wipe when toe latch rests against
the stop pin (23). No adjustment is provided and
a visual inspection is usually all that Is required.
If this setting is not correct, look for insufficient
travel of toe trip shaft (7).
Trip Armature Travel

' Hel^To'TIgurTTi The trip armature (4) should
have 1/16 to 3/16" travel before the trip latch (8)

starts to move plus 1/32" minimum cvertravel after
tripping.

This can be adjusted by moving the trip coil support
(2) and/or by adjusting toe trip armature screw (12)
Figure 11. A locking screw located behind the trip
armature screw must first be loosened. Retighten

locking screw after making adjustment.
Release Latch Wipe

Refer to Figure 6. The wipe between toe release

latch (8) and roller (6) should be 3/16" to 1/4",
If re-setting is required, loosen, set, and retighten adjustment nut and screw (10).
Release Latch Monitoring Switch

Figure 10. (803961?) Adjustable Coupling For
Making Primary Contact
Wipe Adjustments

Operating Rod

2.
3.

Operating Rod Pin
Adjusting Nut

Check Nut

Stationary Primary Contacts

6.
7.

Yoke
Contact Arm

Movable Primary Contacts

* Indicates revision

Refer to Figure 6. The release latch must be
fully re-set and toe latch monitoring switch (13)
operated before toe motor will start. When toe
latch is fully reset toe clearance between toe switch

striker arm and toe switch mcuntiiig bracket (14)
is 1/32" or less, this can be adjusted by bending
the striker arm.

Motor and Relay Switches

Ref-^r to Figure 6. With toe closing springs
blocked rotate toe switch cam (2) until toe switch

GEK-41902 Magne-blast Circuit Breaker

Figure U. (8039585) Auxiliary owitch and
Trip Coil

Open - Close Indicator

2.
3.

Auxiliary Switch
Prop Spring

Trip Latch Spring

Spring Discharge Crank

Positive Interlock Sbait

Cotter Pin

Switch Arm

7.
8.
9.

Trip Coil Support
Trip Coil
Mounting Bolts

Switch Support

Interlock Switch

Auxiliary Switch

10.

Latch Set Screw

Trip Latch

Switch Support

11.

Latch Checking Switch

12.
13.

Trip Arm Screw
Manual Trip Lever

Switch Arm

Trip Shait

striker

(3)

has traveled the maximum amount

(about 180 degrees rotation of cam). At this point

Figure 12. (8034474) Positive Interlock Switch

to its maximum travel.

Now check the clearance

between the ratchet toothandthelatchingpawl. The

the clearance between the striker and the switch

clearance should be approximately equal for both

support (5) should be 1/32" or less. This can be

the driving and latching pawls and not less than

adjusted by loosening the switch support mounting

.015" in either case.

bolts (4) and rotating the support.

If adjustment is required for either pawl the
springs must first be fully charged and blocked.

Interlock Switch Wipe

Loosen seven motor sxip^rt bolts (2) Figure 1

Refer to Figure 12. With the positive interlock
in the reset, or normal position the clearance
between the interlock switch arm (2) and the switch

mounting plate (3) should be 1/32" or less. This
can be

adjusted by bending the switch arm.

Driving Pawl Adjustment

Refer to Figure 4.

The drivii^ pawl (8) must

advance the ratchet wheel (6) sufficiently on each

stroke to

allow the latching pawls (2) to fall

into the ratchet teeth. This should be checked with

the closing spring load against the driving members.
With the mechanism unblocked, hand charge the
closing springs with the manual charging wrench
until they are slightly more than half charged.
Slowly rotate the charging wrench until the driving
pawl has traveled through its return stroke and
check the maximum clearance between the pawl
and the ratchet tooth. Rotate the charging wrench
until the driving pawl has advancedthe ratchet tooth

• Indicates revision

and move entire motor assembly to the rear if
the clearance is under the minimum at the latching
pawls, and to the front if the clearance is under
the minimum at the driving pawl. Move the motor
assembly approximately twice ^l^e dimensional in
crease required at the pawl.
Be certain the
mbtor assembly is moved straight forward or
rearward and tighten the one l»lt on the "right side
of the mounting frame first to assure proper
alignment. After tightening the remaining bolts
the springs should be released and the clearance

again checked as described atx>ve.
Crank Shaft End Play

The outlxsard cranks (12) Figure 7 on the crank
shaftshouldbe adjusted so the end play side to side
is less than 0.015 inch. After this adjustment is
made, the clearance of the prop pin (13) Figure 7 to
the frame is a minimum of 0.025 inch.

Magne-hlajt Clpcutt Br«»ker GEK-41902
AUXILIARY DEVICES
Latch Checlcine Switch

Refer to Figure 13. Charge the closing springs
sufficiently to reset the mechanism link^e. Rotate
the trip latch (4) by pressing the manual trip lever

::: -V v

1
Figure 14. (8034464) Plunger Interlock
1.

Plunger Bolt

Washer

Breaker Lifting Rail

Figure 13. (0114C5320) Latch Checking Switch
1. Switch Support
5. Reset Pin Stop

Latch Checking Switch 6.

Latch Roller

Switch Arm

Latch Roller Link

Trip Latch

Latch Roller Pin

to open the latch checking switch (2).

Allow the

Figure 15. (8034471) Driving Elements

trip latch to reset slowly and deterrnine the point
at which the contacts are made by using a circuit
continuity tester {light indicator, bell set, etc).
The contacts of the latch checking switch should
just make when the g^ between the trip latch

(4) and the stop pin (5) located on the latch roller

link (7) is l/lo".

There should be a minimum ot

1/64" between the switch arm {3} and the switch
support (1). To obtain adjustment of the latch check

ing switch, bend the latch checking switch arm

1.
2.

Moimting Bolts
Manual Close Button

Eccentric

4.
5.

Retaining Ring
Hex Charging Stud

6.
7.
8.

Driving Link
Motor Support
Retaining Ring

9.
10.

(3).

Motor
Fuse

Plunger Interlock

Refer to Figure 14.

With the breaker in the

closed position, the vertical distance "A" from the
top of the plunger bolt (1) to the bottom of the

breaker lifting rail (3) should be 16-19/32" to

16-23/32".

spection and Test

To change this adjustment, add or

remove washers (2).

Amdliary Fuses

Primary contact wipe:

Arcing contact wipe;

"K" syffi*, asetc^tprotectingfuses (10) are mounted
These fuses are the

primary protective devices for the closing control
circuit on those oreakers that are used in metal-

clad units designed for solenoid operated breakers.

•

Primary contactgap:3-5/8"to3-15/16".

Trip latch wipe; 3/16" to 1/4" with trip

Trip armature travel lA6"to3/16"piu8

f.
g.

latch resting against stop pin.

1/32" m'limum overtravel.
Release latch wipe; 3/16" to 1/4".
Release Utch monitoring switch: Max
imum clearance 1/32".

• Indicates revision

1/4" to 5/16".

5/16" or greater

gap at primary contacts.

Refer to Figure 15. On breakers with a "C" or

on the front of the breaker.

For ease in reviewing the adjustments, the
following are recapitulated;

GEK-41902 Magne-blast Circuit Breaker
maximum

tangent to the lower surface of the probes on the
upper runner. Proper servicing and lubrication

Interlock switch: maximum clearance
1/32".

of the breaker and its operating mechanism should
maintain these speeds and no adjustment is provided.

Driving and Latching Pawl: minimum

Latch checking switch contacts make

Motor and relay switch:

clearance 1/32".

clearance to ratchet teeth .015".

when the gap between the trip latch
and the stop pin is 1/16".

Plunger interlock: 16-19/32" to 16-

23/32".
2.

Check all nuts, washers, bolts, cotter pins,
and terminal connections for tightness.

Inspect all wiring to make sure that no
damage has resulted during installation,

Control Power Check

After the breaker has been operated several
times with the manual charging wrench and the
mechanism adjustments are checked as described,
the operating voltages should be checked at the
release coil, trip coil, and motor terminals.
Control Power for electrical operation of the
breaker may be from either an alternating or
direct current source. The operating ranges for
the closing and tripping voltages as given on the
breaker nameplate, are as follows:

and test for possible grounds or short
circuits.

See that all bearing surfaces of the mech
anism have been lubricated.

section on LUBRICATION.

Refer to the

Operate the breaker slowly with the manual
charging wrench and note that there is no
excessive binding or friction and that the
breaker can be moved to the fully opened and
fully closed positions.

Range

24v
48v
llOv
125v
220v

Tripping
Range
30v d-c

d-c
d-c
d-c
d-c
d-c

SOvd-c
115v d-c

130V d-c
230v d-c

115v a-c

260v d-c
12Sv a-c

230v a-c

250v a-c

250v d-c

60v d-c

125v d-c
140v d-c
250v
280v
125v
250v

d-c
d-c
a-c
a-c

See that any place where the surface of the
paint has beendamaged is repainted immed
iately.

Closing

(Page 16 and

Figure 17).

Nominal

Voltage

If the closed circuit voltage at the terminals

Check the trip coil plunger and the release
coil plunger to see that they move freely.

Opening and Closing Speeds

of the coil or motor does not fall in the specified

range, check the voltage at the source of power and
line drop between the power source and breaker.

When two or more breakers operat^ from the

The closing speed of the arcing contact of the
breaker should be a minimum of 11 feet per second.
This represents the average speed of the movable
arcing contact from a point 3" before the tip is

tangent to the lower surface of the probes on the

upper arc runner to the tangent position.

The opening speed of the arcing contact should
be a minimum of 12 feet per second. This repre
sents the average speed over 3" from the point
when the tip on the movable arcing contact is

same control power source are required to close
simultaneously, the closed circuit voltage at the
closing coil or motor of each breaker must fall
within the specified limits.

Electrical closii^ or openingis accomplished by
energizing the closing or trip coil circuit. Control
switches are provided for this purpose on the
metal-clad unit. It is also possible to trip or close
the breaker manually by pressing the manual trip
lever (8) Figure 5 or the manual close tutton (9).

GENERAL MAINTENANCE
General

Safe and dependable service from electrical ap
paratus and power systems is contingent upon re
liable performance of power circuit breakers. To

every 2000 operations, or onceperyear,whichever
comes first.

If the breaker is also required to

interrupt fault currents during this period of time
additional maintenance and replacement of parts

obtain maximum reliability the breaker should be

may be necessary.

The breakers are designed in accordance with ap

FORMED, MAKE CERTAIN THAT ALL CONTROL

inspected and maintained on a regular schedule.
plicable standards which require that they be
capable of performing up to 5000 operations for
1200 ampere breakers and 3000operations for 2000
ampere breakers switching rated continuous cur
rent before any replacement of parts should be

necessary. This requirement is based on the
breakers being serviced, or maintained, at least

BEFORE ANY MAINTENANCE WORK IS PER

CIRCUITS ARE DE-ENERGIZED AND THAT THE
BREAKER IS REMOVED FROM THE METAL-CLAD
UNIT.
DO NOT WORK ON THE BREAKER OR
MECHANISM WHILE D* THE CLOSED POSITION
UNLESS THE PROP AND TRIP LATCH HAVE
BEEN SECURELY WIRED OR BLOCKED TO PRE-

ne-bla«t Circuit Breaker GEK-41902

VENT ACCIDENTAL TRIPPING. DO NOT WORK
ON THE BREAKER OR MECHANISM WHILE THE
SPRINGS ARE CHARGED UNLESS THEY ARE"
SECURED IN THAT POSITION BY THE MAIN-

TENANCE SPRING BLOCKING DEVICE.

Periodic Inapection

Uttle or no inspection unless there is evidence
of damage to the arc chutes sides or contamination
m the throat area. If either of these conditions
are present the interrupters should be removed

from the breaker and the following points noted:

1. The throat area of the interrupter should
be cleaned with san(h)aper {Do Not use

The frequency of the Inspection and maintenance

emery cloth or other metallic abrasives).

operations required should be determined by each
operating company and will depend on the applica
tion of the breakers and the operating conditions.
Factors which should be considered are: Import
ance to overall plant or system operation; number
of operations and magnitude of currents switched by

All flat areas on either side of the movable
arcing contact travel should be sanded.

Do not sand or otherwise attempt to clean
me ceramic fins of the arc chute sides.

Heavily contaminated parts should be re

• breaker; frequency of fault interruptions; and the
atmospheric conditions in which the breaker nor

mally operates.

Extreme conditions of dust,

placed.

moisture, corrosive gases etc., can indicate that

inspection and maintenance will be required more
frequently than every 2000 operations. Very clean
dry operating conditions with low current switching
duty can justify a longer period of time between
inspections.
Any time a breaker is known to

have interrupted a fault at or near its rating it
is recommended that the breaker be inspected and

the severe heat of an arc.

The following

arc chute sides will not interfere with its

in an inspection and general recommendations on

performance and can be disregarded.

the maintenance of breakers.

^
"V

Since there are no movingparts, the interrupters
of a magne-blast breaker will normally require

H the arc chute has suffered any mechanical
injury due to dropping or accidental striking,
resulting in the actual breaking off of fins,
replacement will be necessary. Small
broken corners on the eAaust end of the

instructions give the items that should be included

Interrupters

These cracks

do not interfere with the operation of the
device in any way andshould be disregarded.

necessary maintenance be performed as soon after

the interruption as is practical.

Cracks which have formed in the fins of the
arc chute are to be expected in ceramic
materials of this type when subjected to

The plastisol flexible covering for the pole
pieces (3 & 6) Figure 18 shouldbe inspected
for breaks in the insulation. If there are

holes or breaks in the insulation they
should be repaired or the part replaced.
• Electrical Connections

To assure

that

the

electrical connections

, have remained tight, they should be checked during
installation as well as during each maintenance in
spection. This check of electrical connections is
particularly necessary on breakers used in nuclear

generating stations and other critical ^plications.
The bolted braid connections onthestationary arcing
contacts shouldbe checked for tightness by removing
the arc chutes as described on page 15.

f
Rear Bushing
Supporting Bolt

Upper Interrupter Support

Stationary Arcing Contacts
Movable Arcing Contact
Mounting Bolts
Arc Chute Brace

Support Bracket

Lower Supporting Bolt
Lower Interrupter Support

'Cas.

Interrupter

Figure 16. (6917442A) Interrupter Removed Showing Accessibility of Arcing Contacts
• Indicates revision

Hagse-UMt OsKft Breaker GEK-41902

The lubrication chart, Figure 17, is dividedinto
two methods of lubricaUon. The first method out
lines the maintenance lubrication which should be

performed at the time of periodic maintenance, and
requires no disassembly. The second method out

lines a lubrication procedure similar to that per-

formed on the breaker at the factory, and should be
used when a general overhaul of the breaker is
necessary.

General Electric LubricantsD50H15 andD50H47

are available in l/41b collapsible tubes. It is so

packaged to insure cleanliness and to prevent
oxidation.

LUBRICATION AT
PARTS

MAINTENANCE PERIOD

Prop & Trip Shaft Bearings
(Teflon coated bearings)
Sleeve Bearings - main crank shaft,
mechanism pawls, spring charging
and operating linkages, etc. (Bronze)

ALTERNATE LUBRICATION

(REQUIRES DISASSEMBLY)

No lubrication required

Light application of machine

Remove bearings or links,

oil SAE 20 or SAE 30.

clean per instructions and
apply DS0H15 lubricant

liberally.
Contact Arm Hinge Assembly
Cup Bearing

No lubrication required

Wipe clean and apply D50H47

Roller and Needle Bearings

Light application of machine
oil SAE 20 or SAE 30.

Clean per instructions and repack with D50H15 lubricant.

Ground surfaces such as cams, ratchet

No lubrication required.

Loose rings between bushing and
contact arm

teeth, etc. (Surfaces coated with M0S2)
Ground surfaces such as latches,
rollers, prop, etc.

Wipe clean and apply

D50H15 lubricant

D50H15 lubricant.

Silver plated contacts and primary

Wipe clean and apply

disconnect studs

D50H47 lubricant

D50H47 lubricant.

Booster Cylinder

Do not lubricate

Arcing Contacts

Do not lubricate

Figure 17. Lubrication Chart

METHOD OF CLEANING
BEARINGS

Sleeve Bearings

The sleeve bearings used in the prop(14)Figure 7 and the bearings for the trip shaft (7) utilize

Whenever cleaning of bearings is required, as
indicated in the lubrication chart, the following pro

Teflon surfaces and do not require lubrication.

cedures are recommended.

After a number of operations, the surface will ac-

* Indicates revision

GEK-41902 Magne-blast Circuit Breaker
* quire a thin black film. Do not remove this film
unless there is evidence of outside contaminants, .

the alcohol in a well ventilatM room; excessive
exposure to the fumes is sometimes unpleasant

such as dry or hardened grease. If contaminants

to personnel.

are present they should be removed by immersing
the prop and bearing in clean petroleum solvent, or

should follow immediately.

similar cleaner, and using a stiff brush.

Do not
remove the bearings from the prop or frame. DO
NOT USE CARBON TETRACHLORIDE.

The remaining sleeve bearings located in the

driving element and the mechanism linkage and

Washing the l)earings in the light

oil, draining and repaying with lubricant D50H15

factorily with petroleum solvent or a similar
cleaner and a stiff brush.

Follow the procedure

outlined above using a li^t machine oil and G-E

D50H15 lubricant at general overhaul periods. This

lubricant D50H15 before reassembling the inner

includes the bearings in the driving link (6) Figure
15, driving pawl lever (10) Figure 4, driving pawl
(8), latching pawls (2), trip latch roller support
{10) Figure 7, cranks (3), and the bearings in the

race and shaft.

Rolling Surfaces

mechanism frame and interconnecting links. Bear -

mechanism have been lubricated with a baked-on

ings that are pressed into the frame or other mech
The cup bearing (24) Figure 8 of the primary
contact arm should be disassembled, cleaned,
and lubricated with G-E D50H47 lubricant at gen
eral overhaul periods.

The main shaft bearings (24) Figure 7 should

be removed, cleaned, and lubricated with G-E
D50H15 lubricant at general overhaul periods.

6), latch roller bearing (9), and cam shaftbearings
(25) should be removed from the mechanism and

the inner race disassembled. They should then be
nlaced in a container of clean petroleum solvent
or similar cleaner.
DO NOT USE CARBON
TETRACHLORIDE.. If the grease in the bearings
has become badly oxidized, it may be necessaiT to
use alcohol (type used for thinning shellac) to
remove it. Ordinarily, by agitating the bearings in
the cleaning solution, and using a stiff brush to
remove the solid particles, the bearings can be

satisfactorily cleaned. Do not handle the beari^s
with bare bands as deposits from the skin onto the

bearings are inductive to corrosion. If the bear

ings are touched the contamination canberemoved
by washing in alcohol. Afterthebearingshave been
thoroughly cleaned, spin them in clean new light

dry, molybdenum disulfide coating. This lubri
cation, wiilch'can be recognized by its dark, almost
black color (e.g. Face of switch cam (S) Figure 2)
requires no maintenance and should last the life
of the breaker.

Other rolling or rubbing surfaces that are not
lubricated with molybdenum disulfide should have
the dried, dirty grease removed and a thin film
of fresh lubricant DS0H15 iqiplied.
MAINTENANCE

Magne-blast breakers used for switching arc

furnaces or capacitors will require more frequent
and more detailed inspection and maintenance

The following schedule is recommended for such

breakers:

A. Every 500 Operations, or Every SixMonthsWhichever Comes First:

of the box barriers.

ed by using sanc^aper. This cleaning •
chute sides should not be cleaned.
Whenever the intemq>ter is removed,
loose dust and dirt should be blown
out before replacing arc chutes. Throat
insulation which is heavily contaminated

If it becomes necessary to clean the

• Indicates revision

All flat parts in the throat area of the
interrupters shouldbe thoroughly cleanshould be performed any time the interrupter is removed. The fins on the arc

bearings in alcohol (shellac thinner), be sure
the alcohol is perfectly clean, and do not allow the
bearings to remain in the alcohol more than a few

Remove the box barriers.

2. Wipe all insulatingparts cleanofsmoke
deposit and dust with a clean dry cloth,
including the bushings, and the inside

sure all metal parts are greased. The inner races
should then be assembled.

hours. If it is desirable to leave the bearings in
the alcohol for a longer time, an inhibited alcohol
such as is used for anti-freeze should be used.
Even then the bearings should be removedfrom the
alcohol within tweiity-four hours. PrecauHons
asainst the toxic effects of the alcohol must be
«ercised by wearing rubber gloves and by usmg

•

because of the repetitive nature ofthe applications.

machine oil until the cleaner or solvent is entirely
removed. Allow this oil to drain off and then repack
them immediately with G-E lubricantD50H15being
NOTE:

A number of rolling and robbing surfaces in the

Roller and Needle Bearings

Refer to Figure 7. The cam follower bearings

Bearings that are pressed into tiie frame or other
members such as the motor support (7) Figure 15,
should not be removed. After removing the shaft
and inner race the bearing can be cleaned satis

frameshouldbe cleaned and relubricated with G-E

anism members should not be removed.

should be replaced.

B. Every 2000 Operations,or EverySixMonths
Whichever Comes First:

to the servicing done each

500 operations, the followinginspectirTi
should be made and work done when
required.

Magne-blast Circuit Breaker GEK-41902

r""^

Primary Contacts (3 and 10 Figure 23)..

positions.

Inspect the condition of the stationary

should then be checked using either the

contact fingers and movable contact
blocks. Badly pitted or burned contacts

should be replaced. (Note: Burned
primary contacts indicate the probable
need for arcing contact replacement!)
If the contact surfaces are only rough
ened or galled, they should be smoothed

test

runners

connections

NOTE: Fine cracks may develop in the
fins of the arc chute sides. This is to

wear.
The buffer blocks and their
retainers on the bottom of the stationary

be eiq>ected witti ceramic materials
when subjected to the high heat of an
arc and may be disregarded unless
they are long and present a possibility
ctf fin sections breaking completely off.
Small broken comers on the exhaust

contact support should be Inspectedfor
possible need of replacement.

The contacts of the control relay (17)
Figure 6, should be inspected for wear

end of the arc chute will not interfere

and cleaned if necessary.

anism in accordance with instructions

lubrication chart Figure 17.

Inspect all wiring for tightness of con
nections and possible damage of in
sulation.

with its performance and can also
be disregarded.

Lubricate the breaker (q)erating mech

under LUBRICATION, page 16 and the

After the breaker has been serviced,
it should be operated manually to be
sure thare is no hindinp or friction
and that the breaker contacts can move

to the fully opened and fully closea

Any parts damaged or severely burned
and/or eroded from arc action should
be replaced.

cam, latch and roller surfaces should
be inspected for damage or excessive

Tnmiiating material that is carbonized
and cannot be satisfactorily cleaned
should be replaced.

nuts, bolts, retaining rings, etc., all

Check the stationary arc contacts to

assure that the arci^ contacts are in
good condition and Uiat their connections
are tight.

scribed under ADJUSTMENTS.

The breaker and operating mechanism
should be carefully inspected for loose

The arc runners should be inspected
and replaced when any part of their
area has been reduced to 25% of the
original metal tttickness as a result
of arc erosion.

readjustments should be made as de
5.

should be checked for

tightness.

Check the breaker and mechanism ad

justments as summarized under IN

The blow-out coils should be carefully

coils are not fully insulated from each
other, ttie coils should be replaced. All

anv circumstances.

SPECTION AND TEST. The necessary

can

cracked, shrunk or eroded from arc

tact condition indicate a need for re

which

action and heat so that &e turns of the

The contacts should be

Do not grease the arcing contacts under

assemblies

examined and if the insulation has been

injected lor uneven wear and/or dam
age using a mirror to inject the

placement. If the interrupters are re
moved, the contact braids, and other
parts subject to arcing should be check
ed for possible cleaning or replacement.

and

become contaminated by arc products.

than the minimum specified under AD
JUSTMENTS, the contacts should be

stationary contacts. Normally it will
not be necessary to remove the internq;>ter8 for this 2000 operation ser
vicing unless inadequate wipe or con

In addition to the servicing done each
2000 operations, the interrupters should

assembled to permit a detailed inspec
tion of insulation, blow-out coils, arc

should be greased lightly with D50H47.

replaced.

cabinet or the test couplers.

be removed from the breaker and dis

contact dressing the primary contacts

Arcing Contacts (6 and 27 Figure 8).
T^en the arcing contact wipe is less

electrical operation

C. After Every 10,000 Operations:

with croctis cloth or draw filed. Alter

Its

The cup bearing and the contact ring
at the hinge point of the contact blade
should be disassembled, inspected,
cleaned, and relubricated with G-E
contact lubricant D50H47. The contact

ring should be inspected for wear and
r^aced when reduced in thickness to

less than 1/32". When reassembling
the cup bearing, be sure the cotter

pin is properly assembled in the castte

nut on the hinge pin (T) Figure 23.
This assures proper contact pressure
at the hinge.

GEK-41902 Magne-blast Circuit Breaker

Every 20,000 operations or Approximately
Every Five Years - Whichever comes iirst:
1.

The bre;Jcer should be given a general
inspection and overhaul as required.
All excessively worn parts in both the

Remove the side brace (5), and pole pieces
(3 & 6).

To remove the upper arc runner assem

bly (4) Figure 20, remove assembly bolt

(1) Fi^re 18.

mechanism and breaker should be re

placed.

Such wear will usually be

indicated when the breaker cannot be

adjusted to indicated tolerances. This
overhaul and inspection is more detail
ed and will require disassembly of mech

Remove ttie assembly bolts (15) Figure
18 to remove the lower brace (8).

anism and breaker operating parts.

Remove the lower internroter siq>port (13)
by removi^ the assembly bolts (14) and
the connection nut (8) Figure 20.

All roller and needle bearings in the

operating mechanism should be dis
assembled, cleaned, and repacked with
G. E. lubricant DS0H15 as described

6. At this point, the throat shields (5) Figure

20, ud the Lower arc runner assembly (6)

under LUBRICATION.

The stationary primary contact fingers

(3) Figure 23, should be disassembled
and the silver-plated pivot area of the
contact and contact support cleaned
and

lubricated

c^ be removed.

by removing the various screws and assem

bly bolts (not Illustrated) as shown in

with G-E lubricant

Fic^re 19.

D5CH47.

The breaker and operating mechanism

should be serviced as described for

every 2,000 operations and properly
adjusted before being put back into
service.

REPAIR AND REPLACEMENT

This section covers the proper method of

Reassemble the interrupter in the reverse order.
The following items should be noted during re
assembly:

and in line.

.21) should be 1/64" to 3/32".

Check to insure that electrical connections
to the blowout coils are tight.

When reassembling the arc rmmer as
semblies, check that the spacers are cor
rectly InstaUed.

Before bolting the upper s^ports in place,

and arc runners):

(7) Figure 8.

The interrupter can now be re

moved as described under INTERRUPTER RE
MOVAL AND REPLACEMENT page 16.

make certain that the ujqier arc runner

assembly is tight against the arc chute
side so that die g^ between the throat

To disassemble the interrupter after it has been
removed from the breaker, proceed as: follows:
NOTE:

reassembled correctly.

insulation (7)

Remove the assembly bolts (7, 9, 11, &13)
Figure 18.

Fi^re 19, and the arc

chute sides (6) is a minimum.

When disassembling the arc chute and

its components some small washers, spacers,
etc.,
be found that cannot be identified in
these instructions.
Care should be taken to
collect and identify these items so they can be

The gap between the fins at the rear of the
arc chute sides measuredatleastl"infrom
the back end of the arc chute (See Figure

JUSTMENTS and FINAL INSPECTION.

With the breaker open and the closing springs
in the blocked position, remove the box barriers

The fins of the arc chute sides should be

equally spaced and aligned before bolting
together. The front edge (along therunner)
of the two arc chute sides should be parallel

or replacement at the installation. Ilfl'ORTANT;

ARC CHUTE (To inspect or replace blow-out coils

The arc chute sides (6) Figure 19, can
also be separated for Inspection after
removing assembly bolts (2 & 4) Figure
18.

removing and replacing those parts of the breaker
subject to damage and wear that may require repair
UPON COMPLETION OF ANY REPAIR WORK, ALL
BREAKER AND MECHANISM ADJUSTMENTS MUST
BE CHECKED.
Refer to the section on IN
STALLATION, paying particular attention to AD

Further disassembly of botti the uiq)er and
lower arc runner assemblies can be done

Make certain that the electrical connectioiis

(2 St 8) Figure 20 are tight.
ReassemMe the arc chute on the breaker as

described under INTERRUPTER REMOVAL AND

REPLACEMENT, page 16.

•r GEK-41902

•10

Assembly Bolts and Bushing
Assembly Bolts
Upper Pole Piece
Assembly Bolt
Side Brace

Lower Pole Piece

Assembly Bolt
Lower Brace

Assembly Bolt
Upper Interrupter Support'
Throat Shield

Assembly Bolt

Lower Interrupter Support

Assembly Bolts
Assembly Bolts
t

iJi •"•

'ari

Figure 18. (8917442E) Interrupter Assembly

Upper Arc Runner Spacer

Upper Arc Runner Assembly
Blowout Core
Blowout Coil

Upper Arc Runner
Arc Chute Side
Throat Insulation
Lower Shield
Lower Arc Runner
Blowout Coil
Blowout Core
Lower Insulation

Lower Arc Runner Assembly
Lower Coil Connection

Lower Arc Runner Spacers

Figure 19. (8917442D] Interrupter Assembly with Side Removed

GEK-41902 Magne-blaflt Circuit Breaker
CONTACTS

Open the breaker and remove the box barrier
and interrupters as previously described.
To
remove the contacts, proceed as follows:
A.

Stationary Arcing Contacts (10) Figure 22.
1.

Disconnect the contact braids (7) from
the contact fingers by removing two

bolts and locidng plates (8).
2.

Grasp the lower end of the contact
fingers with pliers and pull contact
assembly downward to remove from
stud assembly.

3.
4.

To disassemble braids from stud plate
remove one bolt (5).
To disassemble stud plate from contact

support, remove two bolts (6).
5.

Reassemble in the reverse order, make

sure locking plates are properly re
assembled with bolts (8).

Movable Arcing Contact (14) Figure 23.
1.

Remove the assembly bolts (12) making
note of quantity and location of shims
and spacers used between contacts and
contact arms.

Upper Mounting Support

Connection Bolt

Insulation Plate

Upper Arc Runner Assembly

Throat Shield

Lower Arc Runner Assembly

Lower Coil Connection

Reassemble in reverseorder, re-using

the shims and spacers.

Figure 20. (8917442C) Interrupter Assembly
3.

Close the breaker slowly to check
that the movable arcing contact is

^proximately centered on the station
ary arcing contact and that it does
not rub on either side of the throat
barrier (9).
NOTE: Whenever it is found necessary

Connection Nut

Lower Mounting Support

to replace arcing contacts on any pole
of a breaker it is recommended that

both the stationary and movable con
tacts on that pole be replaced at the
same time.

C.
'

Stationary Primary Contacts (9) Figure24.
1.

Compress the contact spring (6) by
use of the spring conqiressor.

2.
3.

Remove spring and spring guide (1).
Raise the contact finger to clear the

primary contact stop plate (8) and lift
the finger out of contact support (7).
Remove one contact finger at a time.

To replace the Stationary Primary Contacts:

1.
Figure 21. (80293731 Arc Chute Fin Spacing

Apply a thin coating of D50H47 zrea-'e
on the hinged edge ot the finger (9) then
place it on the contact support (7) so

lOTM-bUct OreMBrmkar GEK>41d02

L
Rear Bushing

Guide and Support for Interrupter
Bolts for Contact Support
Contact Siq)port
Bolt for Flexible Braid

Mounting Bolt
Flexible Braid

Connection Bolt

Stud for Mounting Arcing Fingers

Stationary Arcii^; Contact Assembly
Throat Baffle

I-m
Figure 22. (8917442B) Rear Bushing Assembly

that it is retained by stop plate (8).
2.

semble spr^ guide, spring and spring

To replace die movable primary con
tacts on a 12(X) an^re breaker proceed as

compressor (Figure 24A).

follows:

Turn nut (2) in clockwise direction to
compress contact spring (Figure 24B).
Hold spring firmly in yoke on spring
compressor to prevent spring from
sloping out of the compressor.

Place washer (not shown) on guide on

top of spring, place top of ^de into

bole in spring retainer (4) and the
rcund end of spring guide in cutout in

primary finger (Fl^re 24C).
5.

D. Movable Primary Contacts (10) Figure 23.

Open spring compressor (3) and as

Hold spring assembly firmly in place
and remove spring compressor.

Disassemble nuts from assembly bolts

(11) and remove the movable primary
contacts (10).
2.

Reassemble in reverse order.

To replace the movable primary con
tacts on a 2000 ampere breaker it is first
necessary to disassemble the movable arc

ing contacts, then proceed as follows:
1.

Disassemble operating rod pin (4),fir8t
noting quantity and location at washers
in the assemble.

GEK-.41902 Magne-blast Circuit Breaker

Contact Arm Assembly (6, 10, 12, 14,
Figure 23).
1.

Remove connection bar (15).

2. Disassemble hinge pin (7), cup bearing
(6), and operating rod pin (4) noting
quantity and location of any washers
and spacers used in assemblies.
3.

The contact arm assembly Including the
piston assembly (13) can now be re
moved.

When reassembling, first insert piston

tube assembly (13) into the booster
cylinder and reassemble the cup bear
ing, TTiairing sure the silvered contact
washers between the bushing and cootact arms (both sides) are in place.

Reassemble operating rod pin (4) and
connection bar (15).

After disassembly and reassembly of any
contacts, check ail contact adjustments as
described under ADJUSTMENT.

BUSHINGS

IMPORTANT:

DO NOT RE&K)VE ALL SIX

BUSHINGS AT ONCE.

Figure 23. (3039588) Contact Assembly
1.

Front Bushing

Contact Springs

Stationary Primary Contacts

Operating Rod Pin

Buffer

6.
7.

Cup Bearing
Hinge Pin

8.
9.

Contact Arm
Throat Barrier

10.

Movable Primary Contacts

11.

Assembly Bolts

12.

Assembly Bolts

13.

Piston Assembly

14.

Movable Arcing Contact

15.

Connection Bar

The bushings have been
carefully aligned with the breaker frame, during
assembly at the factory, and it is Important that
this alignment be maintained to insure interchangeability of the breakers in the metal-clad units. It

is, ther^ore, recommended that the bushings be
removed and reassembled one at a time.

Also,

before removing any one bushing, measure the dis
tance from that particular bushing to adjacent
bushings In both directions, so that it may be
reinstalled in the same location.

However, It is possible to remove and re
assemble three bushings at one time. If this is
preferred, alignment of toe bushings may be
accomplished by placing toe breaker in a de-

energized spare metal-<^d unit before tightening
the bushing mounting bolts.

This must be done

before the interrupters are reinstallad.

To replace toe bushing, proceed as follows:
Rear Bushing

Pry contact arms (8) apart enough to
disengage pivot pins of piston assembly
(13) allowing piston to drop down into

Open toe breaker and remove toe box
barrier and interrupters as already de
scribed.

its booster cylinder.

2.
Rotate the two parts of the contact arm
assembly away from each other so as
sembly bolts (11) are accessible and

movaUe primary contacts (10) can be
removed.
Reassemble in reverse order.

Remove the upper and lower horizontal
barriers (18 and 20) Figure 6.
Remove toe four bolts at toe mounting

flange of the rear
wg being removed
and lower the bushing assembly.

NOTE:

Shims may be found between the

breaker mounting plate and the bushing

e-bUrt Circuit Breaker GEK-4I902

Figure 24A (8034466)

Figure 24B (8034465)

Figure 24C (8034469)

24^ (8034468)

Figure 24. Metbod ot Installing Primary Contact
Springs Using a Spring Compressor
1.
2.
3.
4,.
5.

Spring Guide
Compressor Npt

^ring Compressor

Spring Retainer
Assembly Bolts

6. Spring

7. Cfontact Support
8. Stop Plate

9. Stationary Primary
Finaer

GEK-41902 Magne-blast Circuit Breake
mounting flange on some, or all bolts.
These shims are for squaringup the bushing >
and may be required when new bushings are
assembled.

Referring to Figure 24, disassemble the

prima^ contact springs (6) as previously

MOTOR. RELAY AND LgMT SWITCHES

Two or three switdMS (T) Figure^ are mounted
in tandem as required ^ ai^licadra.
1.

Remove the iqiening spring per instructions
below.

describe.

removing mounting bolts (5).

Remove (2) mounting bolts (4) from switch

Disassemble the spring retainer (4) by

bracket (5).
3.

Remove the (2)

Referring to Figure 22, disassemble the

contact support (4) and interrupter mounting

bracket (2) removing two bolts (3).

screws of die lower

switch.

Remove the (2) mounting screws of die center
switch.

Reassemble in the reverse order.

The

interrtq)ter moimting bracket (2) is not
symmetrical and must be assembled cor
rectly to orient the internq>ter properly
on the breaker. The longest projection of
the bracket should be toward the lower end
of the bushing.

Remove the (2) mounthig screws of the upper
switch.

Disconnect the lead wires of switch to be
replaced.

Reassemble in die reverse order and check

switch adjustmcHBt as explained under AD

Front Bushing

JUSTMENTS.

Open the breaker and remove the box
barrier and interrupters as already de
scribed.

2.
3.
4.

Remove the upper and lower horizontal

barriers (18 and 20) Figure 8.

Remove the connection bar (IS) Figure

TRIP SHAFT AND LATCH (See Figure 11)

1. Remove ^ring discharge crank (5), m^u^
trip lever (13^ and if furnished, the latch
checking switch operating arm (8) Figure
12 from the.trip shaft.

23, ciq> bearing (6) and hinge pin (7).

Disengage trip latch spring (4) Figure II.

Remove the four bolts at the mounting

Remove three (3) cotterpinsfrom trip shaft.

and lower the bushing.

(See note under

When reassembling, first mount the bushing
and assemble the cup bearing(6), contact arm
(8), and replace pin (7) being sure the
silvered contact washers between the bush

flange of the front bushing being removed,

ing and contact arms are in place. The

Check all contact adjustments as outlined

under ADJUSTMENTS.

die key, thm remove the key.

Check for and remove any burrs raised

around the keyway on die shaft to avoid
riarwagifig the trip shoft bearings.

Shaft, latch, eto«. may now be removed by
driving it to- the left. Note quantity and
location of washers lued as spacers in the
assembly.

INTERLOCK SWITCH

Reassemble parts in reverse order. Be sure

trip latch is alijmed in center of trip latch

roller and that the latch spring is properly
installed. Check latch adjustment as de

and check the switch adjustments as explained

scribed under ADJUSTBfE^TS.

under ADJUSTMENTS.

TRIP LATCH ROLLER BEARING

To remove the latch checking switch (7) Figure

screws and disconnect the lead wires. Reassemble
in the reverse order and check the switch adjust
ments as e:q>lained under ADJUSTMENTS.

12, (when furnished), remove the two momting

and the left side of the mechanism frame.

latch is free
6.

LATCH CHECKING SWITCH

Place a block between die tr^ latch (11)

Drive the trip shaft to the left until the

contact surfaces at the hinge point of the
contact blade and bushing should have a thin
coating of D50H47 grease.

To remove the interlock switch (4) Figure 12,
remove the two mounting screws and disconnect
the lead wires. Reassemble in the reverse order

Remove trip arm screw (12) and trip latch
set screw (10).

rear bushings concerning use of shims.)

Remove (2) cotter pins at ends of trip latch
roller abaft (8) Figure 13.

Partially remove ehaft out right side of
frame until latch roller (6) is free.

Magiw-bUst

Reassemble in reverse order with proper
spacing of wsuthers.
rotates freely.

as far as it will go. Slide the shaft to the

Be sure latch roUer

CLOSING LATCH

Remove cotter pins at both ends of closing
latch shaft (9) Figure 6.

Remove spring and paddle (12).

Remove set screws from latch (8).

Move shaft (9) to left (away from frame) by

left until key is fully exposed. Remove key
and check sbaM for burrs*
5.

Remove

Reassemble in reverse order using the
correct number of washers and spacers to

Check closing latch adjustments as de
scribed under ADJUSTMENTS.

MOTOR SUPPORT

To remove motor support (7) Figure 15,
first remove the closing latch spring (12)

Remove tiie retaining ring (4) Figure 15,
Remove

motor leads from the terminal

board.

Remove six 3/8" bolts (1) Figure 15, on
bottom and one 3/8" bolt on the right side
(not shown).

Complete the closing operation and check the
location of the prop pin (13)on the prop (14).
It should be approximately centered.
TRIP COIL

To replace the potential tr^ coil (8) Figure 11,
proceed as follows :

With the breaker in the openposition, remove

Remove tr^ coil sapport (7) and spacers.

Cut wires at the butt connectors and remove

the two mounting bolts (9).

coil.

When replacing the coil be sure to assemble
the correct liber spacers at the ends before
bolting support (7).

Adjust coil location to allow sqn>roximately

1/4" of armature travel before latch starts

to move.

Butt connect wires and check qperation of
solenoid electrically and mechanically.

Remove four mounting bolts from motor
(not shown).

SPRING RELEASE COIL

Remove the retaining ring (8) from the
eccentric (3).

6, proceed as follows:

Reassemble all parts of the motor support

CAM

(6) Figure 4 and remove wheel from main
Remove 2 set screws from switch cam (5)
Figure 2 and remove cam from the main

Remove prop reset spring (4) Fig. 5.
Remove 2 set screws from cam (16) Figure
7, and move cam to the right on the shaft

Remove the left hand closing spring as
described

CLOSING

SPRINGS below.

Remove two mounting bolts (11), coilsupport
(16), and spacers.

Cut wires at tiie butt connectors and remove
coil.

Replace the coll and the correct number of
fiber spacers before bolting support.

shaft.

Block the closing springs as described in
INSTALLATION.

Remove 2 set screws from ratchet wheel

shaft (5).

To remove the spring release coil (15) Figure

in the reverse order and re-align itpn^erly
as described under DRIVING PAWL AD
JUSTMENTS.

If necessary,

move the cam to correct the alignment.

and driving link (6).
3.

Rotate the mechanism through a closing

Figure 7, on the cam (16).

Figure 6.

left side of frame.

Check the location of the cam follower (6)

is free. Shaft will push outside needle bear
ing from bousing.

or pipe when inserting bearing to assure
proper aligiment.

out

operation usingthe manual cha^slng wrench.

Rotate sbidt and continue tapping until shaft

Reassemble in reverse order putting bearing
into frame last. Use a small piece of tubing

shaft

properly locate tite parts.

tapping lightly on the inside end of shaft.

•cwlwrGEK.41902

Butt connect wires and check that the arm

ature is not binding.

Check coil for

electrical operation.

GEK-41902 Magne-blast Circuit Breaker

pushing the
trip lever or block
the opening springs with a suitable blocking

CLOSING SPRINGS

The closing, springs (12) Figure 4, can be

device.

removed as follows:
OPENING SPRINGS
1.

Charge the springs with the manual charg
ing wrench and apply the spring blocking
device

as described in INSTALLATION.

Discharge springs by pushing manual close

To remove the opening springs (4) Figure 4,
proceed as follows:

button (9) Figure 5.
3.

Charge and block the closing springs as
described under INSTALLATION.

Rotate cam shaft (5) Figure 4, by using the

manual charging wrench until the gap be

tween the spring (12) and the bearing block

Push manual trip lever (8) Figure 5, to be
sure the opening springs are fully dis
charged.

(7) is 2 Inches or more.
4.

Lilt both springs until they clear the lower
supports, then pull forward and down imtil

Remove upper pin (I) Figure 4, and lower
pin (9).

the top supports are free.

Either discharge the opening springs by

After reassembling springs check the open
gap at the primary contacts as described
under PRIMARY CONTACT GAP.

RENEWAL PARTS
It is recommended that sufficient renewal parts
be carried In stock to enable the prompt replace
ment of any worn, broken, or damaged parts. A
stock of such parts minimize service internQ)tions
caused by breakdowns, and saves time and expense.
When continuous operation is a primary consider

ORDERING INSTRUCTIONS

of both the breaker and the mechanism.

ation, more renewal parts should be carried, the

amount depending upon the severity of the sendee
and the time required to secure replacements.

Renewal parts which are furnished may not be
identical to the original parts since improvements
are made from time to time. The parts which are
furnished, however, will be intercbsmgeable.
NOTE:
The listed terms "Right" and "Left"
apply when facing the mechanism end of the breaker.

Always specily the conqpletenameplate data

Specify the quantity, catalog number (if W
listed), reference number (If listed), and ^
description of each part ordered, and this
bulletin number.

Standard hardware, such as screws, bolts,
nuts, washers, etc., are not listed and
should be purchased locally.
For prices, refer to tiie nearest office of
the General Electric Company.

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In the following tabulations are listed those parts of the breaker
and operating mechanismwhichareusuallyrecommendedforstock

for normal maintenance. Other parts can be obtained 1^ contacting
the nearest office of the General Electric Company.

Magne-blast Circuit Breaker GEK-4igo2
recommended renewal parts for

type ML-13 stored energy mechanism

USED FOR AM-4.16-250-9 (•) 1200 & 2000 AMPE,
{•) SUFFIX LETTERS - H, C, K, N, R

Fig.
No.

Ref.
No.

Req'd

No.

Description

Catalog No.

Spring Charging Motor - **
48 V-DC

110 Si 125 V-DC & 115 V-AC.

220 & 250 V-DC & 230 V-AC,
6

Relay -

60 Hz
60 Hz

48 V-DC

0137A7575P004
0137A7575P001
0108B5565G004
0137A7575P005
0137A7575P002

110 & 125 V-DC

220 & 250 V-DC

115V-AC, 60 Hz

230V-AC, 60 Hz
5

Potential Trip Coil 110 & 125 V-DC

006174582G001
006174582G015
006174562G002
006174582G013
006174582G032
006275070G001

220 V-DC
250 V-DC

115 V-AC, 60 Hz

230 V-AC, 60 Hz
24 V-DC
48 V-DC
6

006174982G034

Closing Coil 110 & 125 V-DC

006174582G001
006174582G015
006174582G002
006174582G010
006174582G014

220 V-DC
250 V-DC

115 V-AC, 60 Hz
230 V-AC, 60 Hz
48 V-AC

0105C9393P001
0105C9393P002
0105C9393P003

006174582G084

Switch, Normally Open
Switch, Normally Closed
Auxiliary Switch
Closing Latch Spring
Prop Spring
Driving Pawl Spring
Latching Pawl Spring - 0

0456A0866P005
0456A0866P006

0137A9192G011
0161A4231P001

0137A92S2P001
0161A4241P001

0161A5909P001

Refer to breaker nameplate or summary for proper voltage rating.
#

Quantity two (2) rela3rs required on special control circuits. Check
breaker and connection disigram.

Furnish 0161A4241P001 for breakers without closing spring
discharge mechanism.

—»

—o
29

GEK-41902 Magne-blast Circuit Breaker

RECOMMENDED RENEWAL PaRTS FOR
MAGNE-BLAST BREAKERS

TYPE AM-4.16-250-9^

1200 & 2000 AMPERES

(^C^SUFFDC LETTERS H, C, N, K, B, & R)

Fig. No.

Ref. No.

Ampere
Rating
All

Type

•

Catalog No.

No.

Req'd.

0281B0708G002

Operating Bod Assembly

All

0281B0708G008

All

0236C0791G001

Flexible C(»n. Right

All

0236C0791G004

Flexible Conn. Ltf^t

0195A7388G002

Throat Barrier Assembly

0236C0790G009

Arcing Contact Assembly

0121A5964P001

0114C5382P002

0114C5382P004

All

AU
All

0137Agi64P003

0137A9164P004

0108B5543G001

2000

0213X0343G091

1200

•

0213X0343G090

Primary Contact Finger Spring

Primary Contact Finger

Movable Primary Contact

Movable Arcing Contact

Tube & Piston Assembly

1200

0213X0343G091

0152C5960G001

0152C5960G002

Throat Insulation (Right)
Throat Insulation (Left)

0227A5367P00

Lower Runner Shield

0152CS961P003

Lower Insulation Barrier

* * AU Except Breakers with "B" in Suffix

Descr^ition

INITIUCTIONS

GEi - 8876 2A

MAGNE·BLAST CIRCUIT BREAKER
TYPES
AM-4.16-350-lC
AM-4.16-350-lH

CONTENTS
Introduction ................. 1
Receiving, Handling
and Storage ................ 2
Installation ................• 2
Description of
Operation ..............•...4

Adjustments ..................6

General Maintenance ..........12

Renewal Parts •............•.. 30

SWITCHGEAR PRODUCTS CEPARTMENT

GENERAL

fl ELECTRIC

PHILADELPHIA, PA.

GEI-88762

MAGNE-BLAST CIRCUIT BBEAKER

AM-4.16-350-1 (A)

A Letter Designation C, and H, used immediately following the
model number indicates basic deisgn feature
INTRODUCTION

The magne-blast circuit breedcer is the removable interrupting element
. for use in vertical-lift metal-clad switchgear, providing reliable
I
control and protection of power systems. Among the many advantages of
metal-clad -switchgear are added protection to equipment and personnel^
compactness^ simplified installation and reduced maintenance. In keep
ing with these features the magne-blast breakers are designed for interchangeability and maneuverability, together with reliability and low
maintenance requirements.

The magne-blast circuit breaker operates on the principle that an arc
can be interrupted in air by sufficiently elongating and cooling it.
This is accomplished by means of a strong magnetic field that lengthens

^-the arc and forces it into intimate contact with cool dielectric macvi terial.

A sturdy, reliable operating mechanism assures low maintenance

^and long life.
CO

/-^The AM-4.16 magne-blast breaker is available in a number of current

ratings.

Refer to the breaker nameplate for the complete rating infor-

^ mation of euiy particular breaker.

The short circuit conditions to be

0) imposed on the breaker must not exceed its rating, nor should it be
5 csLLled upon to operate at voltages or currents greater than those given

^ on the nameplate. Since this book is written to cover several ratings
of breakers that are of the same general
ign, all instructions will
be of a general character and all illusti*
5ns will be typical, unless
otherwise specified.

PROPER INSTALLATION AND MAINTENANCE ARE NECESSARY TO INSURE CONTINUED

SATISFACTORY OPERATION OF THE BREAKER,

The following instructions will

provide complete information for placing magne-blast breakers in ser
vice and for maintaining satisfactory operation.

These insCmcCions do not purport to cover dJi detdiis or vdridtions in equipment nor to ptovide fot
every possible contingency to be aet in connection with instellation^ operation or maintenance. Should
further inibmation be desited or should particular probleias arise which are not covered suf/icientiy for
the purchaser's purposes, the matter should be referred to the General Slectric Con^any*
To the extent required the products described herein meet applicable ANSI, IEEE and NEHA standards;

hut no such assurance is yiven with respect to local codes and ordinances because they vary yreatly.

GEI-88762
RECEIVIMG, HANDLING, AMD STORAGE
, Receiving and Handling

Each breaker is carefully Inspected and packed by workmen experienced
in the proper handlir^ and packing of electrical equipment. Immediate
ly upon receipt of the circuit breaker, an examination should be made
for any dam^e sustained in transit. If injury or rough handling is
evident, a damage claim should be filed immediately with the transpor-

nSified°"^^"^

nearest General Electric Sales Office should be
care will be exercised during the unpacking

and installation of the breaker so that no damage will occur from care
less or rough handling, or from exposiire to moisture or dirt. Loose
associated v;ith the breaker are always included in the same crate.
Checx all parts against the packing list to be sure that no parts have
been overlooked.

Storage

It is recommended that the breaker be put into service immediatelv in
location. If this is not possible, the following pre
cautions must be taken to insure the proper storage of the breaker;

shoj^d be carefully protected against condenstation, pre

ferably by storing it in a warm dry room, since water absorption has
an adverse effect on the insulation parts. Circuit breakers for outdoor metal-clad switchgear should be stored in the equipment only

cSnSeSLi!

in operatioS tfpSeiLt

2. The breaker should be stored in a clean location, free from corrosive
fumes; particular care should be taken to protect the equip-

cement dust, as this combination has a ve?y
^

corrosive effect on many parts.

parts of the operating mechanism, etc., should be coated
with a heavy oil or grease to prevent rusting.
stored for any length of time, it should be inspected

periodically to see that rusting has not started and to insiire good

®^°nld the breaker be stored under unfavorable

be?oS

INSTALLATION

1. Remove the box border, and front cover and make a visual inspection
to ascertain that the brealcer and mechanism is in satisfactory conditxon. Check all bearing surfaces of the mechanism for lubrication
Refer to section on LUBRICATION (Page 15 ).
xumxcaTjion.

GEI-88762

Charge the breaker closing springs manually using a 5/8" ratchet
wrench to turn the driving eccentric (6) Pig. 4, Turning the eccen
tric coxjnter clockwise will advance the ratchet wheel and compress
the springs.

When the springs have reached the fully charged position the indi

cator (10) Pig. 4 will read "CHARGED", and the driving pawl will be

raised from the ratchet wheel teeth.

Additional turning of the ec

centric will not advance the ratchet wheel.

^sert the spring blocking device (4) Pig. 4 and manualiy discharge"
f

the
springs
the pins
by pushing
releaseof
button
(1) Fig.
4. against
The springs
are now
blocked the
andmanual
slow closing
the

breaker contacts

be accomplished by again turning the driving

eccentric with a 5/8" ratchet wrench.

During the slow closing operation check to insure that the mechanism
does not stick or bind during the entire stroke, that it latches securely in the closed position, and that it trips freely when the man
ual trip lever is operated. The breaker should not be operated
electrically until it has been operated several times manually to
freedom of action. At this time, also check the following
adj ustment s;

a.
s b.

1 c.

Primary contact wipe
Arcing contact wipe

Primary contact gap

(Refer to page 7'
(Refer to page 7
(Refer to page j

WORK ON EITHER THE BREAKER TO MECHANISM UNIESS THE CLOSING

SPRINGS ARE BLOCKED AND THE OPENING SPRINGS HAVE BEEN TRIPPED OPEN
BLOCKED. THIS PRECAUTION IS REQUIRED TO PREVENT
ACCIDENTAL CLOSING OR TRIPPING."

^ter the adjustments have been checked. .e brings can be un^h®^^iving eccentric lUwll the indicator reads
CHARGED and the ratchet wheel no longer is advanced. The blocking

device can now be removed.

3. Attach test coupler to circuit breaker and operate electrically

TROL POWER CHECK" (Page 11 control
and 12).voltage

as described under "CON-

^f®alc®r secondary wiring is to be given a hi-potential
both thethemotor
leads
terminal
connection. P^iure' f®®oye
to disconnect
motor
fromfrom
the the
circuit
may
cause damage to the v/inding insulation,

4, Remove the test coupler and replace box barrier.

GEI-88762

^ ^°"£ period of time. It la recom-

be checkedTEST
with (Page
a atapdard
potential Joa?
teat. Ins^atlon
Refer to INSULATION
14). 60 cjrcle high
primary dlaconnect atuda by

^atiSi on

to form a thin

7. Refer to metal-clad Inatructlon book GEH-I802 for final Inatrupi-ionB
before Inaertlng the breaker Into the metal-clad unit.
DESCRIPTION OF OPERATIQW

The magne-blast breaker la compoaed of two major parta, the breaker

element and the operating mechanlam. The breaker element comprlaea

eon?ap?i an^iS?

^Jta, and
eachanpole
unit conalatlng
of main
and arcing
encloalng
box barrier
that SgrtgS^

phlaea
irSeli^a^rom
to thi aLoSated
dlscSm"frtSds

provide Inaulatlon betwfen
equipment are made through the primary
ground. The primary connectlona

The M^13 operating mechanlam ahown on Plgurea 1, 2 and 3 la of the
stored energy tj^e dealgned to give high apeed cloalnc and onanino-

The mechanism will operate on a-c or d-c voltage aa Indicated on^he
SlctricS bv^th4
opening operatlona are controlled

r-Nty thejMlo'S
~Sp1e? fTpil?

-tal-lad unli a^'mllfSSS^
is^'nof f??ier°?hf

operatfaraddJtlSnirauS??3:a5:?'';wltch^SefuS?t.
b-eLers

MS-13 solenoid operated

Spring Charging

The mechanism consists of a hlch aniap»d o-oar.

s; svsMg- -s-sL-li-Sl
r?n6)'and\\e?er\harc£Jie1Tlp??^'5:falefS?l5S;^'|^„ft5f?""^
€

OEI-88762

1-ho 1,^4. I? r i

tiniiS

^
® '®" degrees each
position by the latching
pawls
fl) When

}

approximately lio degrees the clos-

compressed. As the ratchet wheel con-

to discharge ^
shift over center and attempt
(10) llg 1 will onLSS Lf
degrees of rotation, the closing roller
snrinfs Mill d\, ?f f
dosing latch (ll) and the compressed
^151f
t
repose until a closing operation is required

Srf^litertcck®Lf?^P®®fl?®
fSnm
Sui P

wheel rotation thrSSor

released and the driving" pawl is raised

mechanism to coast to a natural stop expending all residual ener^.
ii^o5

fe!sft "

^^® ®Pdngs are being compressed a relay (6) Pig 6

power circuits open and the relay will remain ener-

thrLS"l oSSacls^e

S£fsSSr£r£»^^
•S|^lS£r«S
over again and continues to charge the springs.

/^Closing Operation

tf^scLJir^^ShflSergv oftE^ blocking locatloh allowing the spSSfs

Ji-J, .A'K.i.s

remains trio fr»<3p ai-' att 4*-tmA«

j j.

ougn a simple linlcage that

Opening Operation

°P®dng operation is initiated by energizinc the trin

eSitih Sllhe'metinilftSrfJeKon^Jj?
bM^r
SSliS of°thropeSin^''lpe?ltiSn^^Se'"o^*'
aprlngs Is thus released, ofening
tte
and

LUBRICATION

w??i ^
?fSj/

the t2«t

JhfJeS-"

foiling surfaces utilize a new type of dry lubrication that
?° "maintenance
and will last the lif^of the eqi^nme^^^
surfaces listed in the chart. Pig 22 recSre
^av® teen poperly lubricated, during assembly at

even the°?fn ^sing the finest grades of lubricants available. However

al
tendency
oxiSze iithn-pagl
as evldenniS^r
evidenced by hardening and darkeninga in
color toEiiminatirtn
hardened lubricant is essential for thi propS SoerSlSi^f
rn®h^®r®'
tion

"'for

^'•awent operation of the breaker causes the lubricant
between the bearing surfaces.

A simple lubrica

seSoSslroSbSS."^"'^ disturbances which might be mistaken

l^trication schedule should be set up taking into conaidera

ni2?i

frequency of operation of the breaker and local condltiSa

SL€r3

SSrSS*:.
' ®®"

sons, or If the operation of the bretker^ewSrslSiLf"
>

OTllaokMrtShe,'"''?!®?"^® °50H15 and D50Ht7 are available In lA #

™nt fSSttoS!"- "

l^au^ cleanliness »d C fre-

Method of Cleaning Bearings
lubrication chart,

I^
15

GEI-88762
Sleeve Bearings

there is evlSlf of outside
fL h^rTnlTn .1 5''®?®",'=

i i ?°
""less
'>« removed by ItnmerilS the^l^

Contaminates, such as dry or hardened erease

3??ff bru^
BON TETRACHLORmE?

01®™®^ fed usl^ a
bearlhgs frorn the links; DO NOT ^ OAR-

S!laneS!®aSd -^""^-Lcatea
iSbrlSStS^w^f0®|
MSnifLbif" ®disassembled,
with G-E D50H47 lubricant at general overhaul

periods!

Roller & Needle Bearings

shaft^beari^s^(25)^pi^®5^ahoSd'be'firat''
roller bearing (9),
and cam
and
the Inne? rioi dlslssLbled^ Thev^hojnjan
raeohanlam

in^^ctl!
bare
handsbrs2tltflctfrun?eaner°'°S
as deposits from the aWn

SS?

bearbearings with

So'J^rriasSn^VS! ®'L'^%®d!>hrcS;gItS^
Ser)f be

^e^'^°
(shellao

bearings to remain in the ai nni-irti

find do not allow the

IS iShfSilr-

iLS^oT

L^rbTil?Sg«^^^^
? filcohol in a well ventilated

room; excessive ejroosure to i-h*b

nel. Washing the bearings in ?ha ??Sh+imraediately, then apply the lubricant. °
16

unpleasant to persondrfiining shoiild follow

GEI-88762

members such as the

mniHno* 4-vick u

Fls*the1^bearing
should not
b© pemoved
After
inner(7)race
can usuSS^
be'cleSiS

petroleumoutlined
solvent above
or a similar
procedure
uslnTacleaner
llSJt

pe-

and a stiff
oil

and Q-E lubricant D50H14 before reassembling thrimer rLfliS Ih^ft.
Rolling Surfaces

xuoricauea vatn a baked-on,
dry, molybdenum t^he
disulflde
mai-infr
lub™oIted^wrth^a"h»5»a
™'"T
mechanism
have been
requires
no maintenance and
shoild iLt t™ Slrof
the toe^ir.

HECOMMEMDED MATNTENANCE FOR MAONE-BLASm BRF««eRS APPT.TRn mn RV»WTmT,n,
St;iTCHING PimT.

breakers applied to repetitive operation such- as switrh

c^dlS^ tnhr?ono„5:S^°schldS^"

maintained ac-

.Every 2000 Operations, or Every Six Months - Whichever Comes
1. Remove the box barriers.

2. Wipe all insulating parts clean of smoke deposit and dust with

bushins8,'ISfL'"?ns?S Sf^
3.

All areas in the throat area of the arc chute should he th«Tv

.^eilLlSr4.

" Inspectcontact
the condition
the uitted
stationary
conct fingers and movable
blocks of
Badlv
n-n hmen

D50H47?^

P-imary contacts should be greased lightly with

Sl^T ®?hf

this aoSo^S^LTs^rv^^J-^SL^"

^s!

t
17

GEI-88762

condition indicate a need for replacement. When the arc chutes
are removed, the contact braids, coil protectors, and other
parts subject to arcing should be checked for possible cleaning

arcing contLta

INSPECTIOn''and^??s?"'^ mechanism adjustments as summarized under

mnHo as
So described
41, 5 under
•
necessary readjustments should be
made
adjustments.

breaker and operating mechanism should be carefully inspec
ted for loose^ nuts, bolts, retaining rings, etc all cam laJrh

wear''°^The bSfer^blo^v'^'^
Inspected
for damage
excessive
J^ocks andbetheir
retainers
on the orbottom
of
neld ol rlpSceSeSt^ support •should be Inspected for possible

cJlanlfJfnecesS^y?""''"'^
SJftlwl 2lLr''L®McS""®
tfLsilaSfoJ?'"

i^^P^^ted for wear and
accordance with
Of connections and possible

the b'realcer has been serviced, it should be slowly closed

«« 1,?^!?® ' as described in INSTALLATION, to be sure thLe ±l

?o
friction
thatclosed
the breaker
contlSI
can move
to the fully opened
and and
fully
positions.
Its electrical

o? tee ?esl cSiplSl?

P®»lnet

B. After Every 5.000 Operationa

' |ptsasiase%

•IliapPssS<

OEI-88762

we r^era ahould be Inspected and replaced when any part

thl!toeL^r=^f
T/nicKness as a result

'='> 25^ of the drlglnal metal

of arc erosion.

stationary arc contacts to assure that the arcing con
tacts are In
good condition and that their" connections ar^tlght.

. SH?e^d°'lhcSfbl'^yicel!''°'^'®-^ and cannot, be aatisfactor0 •
??Sn''Soifrrep?Lir'^''
^"Vor eroded from arc ac"^y develop In the fins of the arc chute
Jected
jecrea to
to tL
the mS
high heat of an arc andceramic
may bematerials
disregarded
whenunieq^
subSmall broken
corners onof
the
'euH breaking
or t-i-io
MmSlttlli°Sff®"'^^airh*
t possibility
finexhaust
sections

conipxeteiy off.

§^°dSreIa?J^i"°'

"""

lerS?mK^"lSd'?fn1llS'

7. The cup bearing and the contact ring at the hinge nolnt of the
contact blade should be disassembled, InSlcted^ cleSL anS
relubrlcated with G-E contact lubricant I50H47 ' The contact

S?fk^s^?o !esfth^®?/3lS

'oPlsced When reduced In

Plye Years - Which
•

1. At this time the breaker should be riven a general overhaul and
n^aJf Such wear will usually be Icated
SechiSIS
placed.
whenind
theSe^er
breaker
ca^ot be adjusted to Instruction c .c tolerances. This overhaul
u
moreoperating
detailed parts.
and will
mechanism
and breaker

regulre disassembly
^sassemblv of
of

*=5® operating mechanism
cant D5OHI5
D^iOHic: as
fo described
I
fu'a® under
j"® LUBRICATION.
'
repacked with G.E. lubri

^d thfll?^^

contact fingers should,be disassembled

SlSnoPt
pivot areawith
of G-E
the lubricant
contact andD50HJ^7.
contact
support cleaned and5 ?lubricated

operating mechanism should be serviced as dea

GEI-88762
TROUBLE SHOOTING

general
classes;^auSe°to^trip^^Illi?e"to^close^^^^?
within four
closing springs will not T»c»^*vio-«£i « i
? close or latch closed,

brief outline showing particular tynea of^diatSS®'i-i,'?® following Is a

ered, together with suggestions foJ^reme^JJl ^hftrouble^®^*'

Failure to Trip

SK?^'°LS?fj2te°ooSpiete"SeStn.y

lubrication.

' ^^^^"cheok^all'
'meohanSm®ad1uet'^- S?®'
*"?
devices, etc., in accordanrS

latches, stops, auxiliary

adjustment,

latch and roller Burfa«Hor

ADJUSTMENTS. Examine

3. Damaged trip coil.

REMEDY:

Replace damaged coil.

4. Blown fuse in trip circuit.

HEMEDy: Replace blown fus^ after determining cause of failure.

5. Faulty connections in trio circuit

or^oose"^^;es and see that all binding

6. Damaged or dirty contacts on trln

REMEDT: Recondition or repLcfUtecS!"

Failure to Close nr Latch
lubrication.

mSt°°Chec^^l°Lch^°^y.°j^gf,^,by_belng out of adjustment,

devices, etc., in accordaneS 2?
latch
and roller surfaces for^orr^Ilon?"

latches, stops, auxiliary

ADJUSTMENTS. Examine

REMEM: °ReMSStloS''o?''repL«°oTOtalts?'^' Including control relay. '
4. Damaged spring release coil
REMEDY:

Replace damaged coil

^Mmr®Re|lMl''|lSSflvfsSitchf

»"lbch.
{

GEI-88762
'/#

5. Blown fuse In closing circuit.

REMEDZ: Replace blown fuse after determining cuase of failure
connections in closing circuit,

broken or loose wires and see that all binding screws
vGlt^e caused by excessive drop in leads.
improve electrical contact at

voltage caused by poor regulation (a-c control)
Failure to Recharge Springs
or closing latch

REI4ED3r:

Replace switch

REMFSDy;

dirty contacts in control circiiit.
Recondition or replace contacts.

^iown fuse in closing circuit.

REMEDY; Replace blown fuse after determining cause of failure.

DCMDw ®°^®obion in charging circuit.

^e^ghtf®^^^ broken or loose wires and see that all binding screws
Overheating

^"ootlon after severe duty

22^ properly
aligned orinadjusted.
.adjustments
accordance with section on ADJUST-

^^£s S 2222^®"

a period.

oontacts clean. Replace

4. Overloading

^ S'loSfor®r^lSSgfSrcSltfsftn2
eu.1 dnge circuits so as to remove excess load.
21

GEI-88762

5* Prljmary connections of inadequate capacity*
REMEDY: Increase size or number of conductors or remove excess cur* wil V •

6, Loose connections or terminal connectors
REMEDY:

Tighten.

7* Ambient temperature too high,

REMEDY: Relocate In a cooler place, or arrange some means of cooling

REPAIR AND REPLACEMENT

The followli^ Information covers In detail the proper.method of removing
Tj^lous p^ts of the breaker In order to make any necessary repairs
those repairs that can be made at the InstalINPORTANT:

£/n
breaker
that REPAIR
are most
subject
to damage
wear*
UPON COMPLETION
OP ANY
WORK
ALL "RRPAKFR
flxmor
Mcnufl

NISM ADJUSTMENTS MUST BE CHEcLT Sffe^tf

^tiS^'^imiSKSN

paying particular attention to ADJUSTMNTS and FINAL INSPECTION,
'
ARC CH17PE AND LOWER ARC RUNNEPtS (To Inspect or replace blow-out colls1

rierrlT^lS

1J 4o

breaker and remove the box bar-

chute remover to the breaker

f 1^?®^
removal
Instructions
20,
Insert the lifting hooks
Into the arc chute
lifting
holes and Pig.
take ud
^®®ove. the mounting hard-

"S breaker.

^0 out of

^reed^arfollowl:^'

'• SruSer'Slg)'^r^!"l:|.(^'

' ®®" removed from the breaker,

off the arc

bfreLred Jfreoesal?^^
3. Remove the assembly hardware (6, 11, 7 and 12) Pig, 16, In the order
Each arc runner segment or blow-out coll may now be removed.
Reassembl® the arc chute in the reverse order. The follovflng Items
should be noted during reassembly.
terns

(

GEI-88762

Equally space the fins of the arc chute sides before tightening the
*'

assembly hardware.

-o

sap between the fins at the rear of the arc chute should be 3/64"

(See Fib

least 1" In from the back end of the arc chute

3. Check to Insure that electrical connections to the blow-out colls are
tight.

4. When reassembling the lower arc runner assembly, check that the

spacers at positions 1 and 6 , pig. 17, are correctly Installed,
5. Make certain that the electrical connections are tight.
To reassemble the arc chute to the breaker, proceed as follows:

sho^^ln Blb'^^18^

chute support bracket (7) as

2. Slide the arc chute forward and lift It slightly to engage the support
supporting bolts (2) Pig. 18 In the support catches
Pig. 20.
n^er unit Is properly assembled; If

not follow Instructions In page ( 25 and 26).

0^. Tighten the supporting bolts (2 and 3) Pig. I8. The bolts (2) are
lower supporting bolt (3) serves as
both the electrical and mechanical connection.
CONTACTS

Open the breaker and remove the box barrle

pJiiefd ts fSloSsf

previously desor

2) side barriers f30^

To remove contacts,

A. Stationary Arcing Contacts (19) Fig. 15B.

1. Remove the glass bonded mica side piece (11) Pig. 15C

2. Remove the asrew holding the contacts braid (16) pig, 153.
3. Turn the contact braid 90 degress and pull out of the arcing
contact finger assembly.

4, Reassemble In the reverse order.
B. Stationary Primary Contacts (9) plg. 23

1. Compress the contact spring (6)

)

2, Remove spring and spring guide (l)
23

GEI-88762

1 c l e a r the primary contact stop plate

To replace the stationary Primary Contacts;
D50H47 grease on the hinged edge of the

is^etalnid brstoriliL^S)?®

8.^port^7) so that It

aasenble spring guide, spring and

'• II'ssriras;r€f^

5. Hold spring assembly firmly In place and remove spring compressor.
C. Movable Arcing Contact (9), pig, 2I.
1. Remove the assembly bolts (8).
2. Reassemble in reverse order.

D. Movable Primary Contacts (6), pig. 21 (igoo AmO. Breaker) "
1. Remove the two lower nuts from assenbly bolts (7),
2. Remove the primary contacts.
3e Reassemble in reverse order.

(3000 Amp. Breaker)

1. Remove the nuts from assembly bolts (7)
2. Remove the connection bar (13).
3. Remove the cup bearing (12).

t: ReHlS: lTthfre'^;:rsi^lSr."°'°'''
E. Contact Blade Assembly (4, 5 &9) pig. 2I.
1. Remove the connection bar (13).

2. Remove the cup bearing (12) and the pin (11).

4. Replace pin (11), and connection bar (13).
24

C*''

GEI-88762

Tertiary Contact Finger (14) Plg. 21.

1. Compress and remove the contact springs (15).
2. Raise the tertiary contact fingers (l4) and slide them out.
^"4" coating
hinged portion of the contacts.

of D50H47 greaae to the

d. Tertiary contact Pad (1) Fig. 21.

Remove two upper nuts from assembly bolts (7),
2. Remove the tertiary contact pad.
reassembly of any contacts, check all contact

adjustments as described under ADJUSTMENTS.
Bushings

lOTORTANT; DO NOT REMOVE ALL SIX BUSHINGS AT ONCE. The bushings have
breaker frame, during assembly at the

and It Is Important that this alignment be maintained to fa-

breaker In thi metal-clad uSt? It Is?

one at a

/•^andrfrom
m
^anae from ?h:^that

flo®

bushings be removed and reassembled

Kremovl^
bushing,
measure
the dlsbushing to any
the one
adjacent
bushings
In both

particular
^ dlreoMons, so that
It may b? reinstalled In the same iSSIttoS.

possible to remove and reassemble three bushings at one time

SaSiS
SfohS^

the spare
bushings
may bra^^il^ld
a de-energlzed
-ital-olad
Vinlt bS^

ust be done before the

To replace the bushings, proceed as follows:

delcrlbld?^®^®^

remove the box barrier and arc chutes as already

^ 2. Remove the upper and lower horizontal barriers (14 and 18) Fig. 8.
bolts at the mounting flangeof the rear bushing being

removed, and lower the bushing and arc runner assembly.

4, For further disassembly refer to Pig. 15.

a) Remove the bolts (8) and spring retainer (7).
b) Remove the nuts from assembly bolts (5 and 6) .
c) Remove the bushing (1).

d) The stationary primary contacts (20) may also be removed If
necessary.

GEI-88762

5. R|^ve the upper aud lower side pieces (2 and 11) and the Insulation
a) Remove the arc runner segments and blow-out coils, Kg. 154.
Front Bushing

?flSir''5lscr?Sd!'
^ arc chutes as al2. Remove the upper and lower horizontal barriers (18 and 20) Kg. 8.
3e Rsnjovs the connsctlon bar

(11).

pii* oi

mm ,

21, cup bearing (12).., and pin

b^^iS^flircoSfact^r™
???"''
' S® bushing and
faces
at the hinge point of
th^eonSi?®wi''i"

assemble the
cup
contact

have a thin coattng^or^WZ |rlSe?
Check all contact adjustments as outlined under ADJUSTMENTS.

sur-

INTERLOCK SWITCH

screws
wires^^^Reaa
mounting
and
checkand^dlscomect^the^eS
the switch adjustmentfar4xpfS®eTS^y"AS?S?S!
LATCH CHECKING SWITCH

To remove the latch checking: switch (7)

pilc

GEI-88762

PARTS recommended vqr NORMAL MAINTEWANCE

Su^Uy*re^^egged1or
Pig.

Ref.

No.

Amps

Type

"hl<=h are
Catalog No.

No.

Description

Per

Brkr.

8
8
8
15
17

29
19
19
24
2

7
7
7
7

1
5
3
3
4
4
6
6
6
6
14

21
21
21
21
21
21
21
21
21
21

4
150
150

17
2
11

6
6
6
6
6
6
6
6
6
6

6
6
6
6
6

11
11

2
2

6
6

5
5

11
11

12
12
12
12
12

All
1200
3000
All
All
All
All
All
All

1200

3000
1200

3000
1200
1200

3000
3000
3000
3000
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All

All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All

6190479 P17

80^730 G1

3
3
3

802B724 PI

281B708 G2

366a4i3 g1

6190464 P9
6557243 P2
383A903 G1

3
6
3
3
24

80^742 G2

414a180
4i4a180
2360791
2360791

pi
pi
p8
p8

36
24

6591644 P7

6
6
6
6

6591644 p8
114C5382 P12
114C5382 PU

2360791 p8

802B724 P2
6591742 PI
6592336 P2

6
6
6
6

6190469 P3

10509393 PI
10509393 P2

Operating Rod Assembly
Operating Rod Assembly
Flexible Lead
Arc Chute Insulating Plate
«
(Mycalex)
Buffer
Buffer Clamp

Station^y Arcing Contact Asr

Arcing Tip Movable

Primary Contact Finger Sprim
Primary Contact Finger Spring
Primary Contact Finger

Primary Contact Finger

Movable
Movable
Movable
Movable

Primary Contact
Primary Contact
Primary Contact
Primary Contact
Contact Stationary i
Tertiary Contact Movable
Cover

Iftjper Runner Insiaation

JJjper Runner Insulation
Motor

48 VDC

Motor
Motor

115 VAC
§30 VAC
48 VDC

Motor 110 VDC - 125 VDC
•totor 220 VDC - 250 VDC

10509393 P3
10509393 P2
10509393 P3

137A7575
137A7575
137A7575
137A7575

Booster Cylinder

P43
P42
P4l
P47

lA
lA

137A7575 P45

lA
lA

6275070 G1 *
1
6275070 G2
2t

Relay

Relay no VDC - 125 VDC
Relay 220 VDC - 250 VDC
Relay 115 VAC
Relay 230 VAC
Trip Coil - 24 VDC

Spring Release & Trip Coil

48 VDC
All
All

All
All

6174582 G1
6174582 G1

110 VDC

Spring Release & Trip Coil
Spring Release & Trip Coil
125 VDC

GEI-88762

-'lg«

Ref,

No.

Amps

HSme

Catalog No.

No.

Description

Per

Brkr.
11

6
6
6

5
10
10

6
11

16
13

All

6174582 GI5

2I:

Spring Release & Trip Coll

All

6174582 Q2

Spring Release & Trip Coll

All

6174582 GIO

Spring Release & Trip Coll

All

6174582 G14

2t:

All
All
All
All
All
All

456A866 P5 .

456A866 Po

IOAXOO6 G4

161A4231

137A9252

161A5909

220 VDC

250 "VDC

115 VAC

Spring Release & Trip Coll
230 VAC

Switch Normally Open
Switch Normally Closed
Auxiliary Switch

Closing Latch Spring
Prop Spring

Pawl ;^rlng

Check connection diagram for (1) or (2) relay requirements.
mulreafor
forrequirements.
tripping.
May be different voltages - check nameplate

0 Not shown.

GEI-88762

21,

P«' 'i!^JS'ir'-.V'";'',-,' 'i.i i'j
••^aijQogAM^.l

Tim"

Fig. 1 Left Side Viev/ rC;-13
Operating Mechanism

1. Secondary Coupler
2. Interlock Sv;itches
3. Auxiliary Sv/itch

Latch Checking Switch

5. Charge-Discharge Indicator
6. Power Switches

7. Closing Springs
8. Motor
9. Fuses

10. Closing Latch Roller
11. Closing Latch
12. Switch Cam

r'ig. 2 Front View ML-13
Operating Mechanism
1. Trip Coil
2. Open - Close Indicator
3. Auxiliary Switch
4. Counter
5. Trip Latch

6. Charge-Discharge Indicator

7. Close Button
3, Motor
9. Fuse

10. Prop Spring
11. Trip Lever

QEI-88762

Pig. 3 Right Side" View ML-13
1. Latching Pawls
2. Positive Interlock Roller
3. Ratchet Wheel
4. Eccentric
5. Fuse

6. Closing Spring

7♦

Main Shaft Bearing

8. Cam Shaft

•9. Opening Spring
10. Guide Block

11. Lower Spring Pin
12. Upper Spring Pin

Fig. 4 Spring Blocking Device
1. Close Button
2.

Motor

3. Fuse

4. Spring Blocking Device
5. Driving Pawl
6. Eccentric

7. Closing Spring

8. Maniial Charging Wrench
9. Support Bolts

10, Charge-Discharge-Indicator

Iinc5320

Fig. 5 Sectional Side View of Mechanism
1. Handle

2. Trip Coll Support
3. Trip Coll

4. Trip Armature
5. Prop Reset Spring

_ Prop Pin
13.

6. Cam Follower Roller

15. Drive Shaft

7. Trip Shaft

OJ
V£>

8. Trip Latch

t00

•

9. Trip Latch Holler

10. Trip Latch Roller
11. Crank Shaft
12. Cranks

14. Prop

16. Cam

17. Check Nut

Opening Spring

Support

18. Stop Plate
19.
20.
21.
22.
23.

Spring Rod
Spring
Spring
Spring Guide
Stop Pin

24. Main Shaft Bearing
25. Cam Shaft Bearing

I
H

GEI-88762

, Switch Cam

Closing Latch Roller
Closing Latch

Latch adjusting Screw
Spring Release Solenoid
Control RelayLatch Checking Switch
Switch Striker

Charge-Discharge Indicator
Power Switches

Latch Monitoring Switch
Motor
Fuse

Switch Support Bolts
Switch Support

Closing Latch Spring
Release Coil Bolts

Release Coil Support
Closing Latch Shaft

Switch Mounting Bracket

Pig. 6

Control Mechanism

Primary Contact wipe (a)
Pig. 7

Arcing Contact wipe (b)

Contact Adjustments

2. Mo?S!n?lm"2njnSSlr'' I- cSSa'?
JopJact Arm

3. Buffer Block

i. stationary Arcing Contacte s! So R^Ser^"''

GEI-88762

H-

00
lO

00
o
00

1. Box Barrier Catch

i/j.

2. Box Barrier
3. Arc Chute

T-'
V

4. Arc Runner, Upper
5. Blow Out Coil, Upper
6. Blow Out Core, ijper

7. Movable Arcing Contact
8. Arc Runner, Lower
9» Blow Out Coil, Lower

10. Blow Out Core, Lower
11. Pole Pieces

'c Chute Support
ring Retainer
wer Horizontal Barrier
operating Rod

19
20* Stationary Arcing Contact
21! Stationary
Primary Contact
22! Movable Primary
Contact
23! Movable Contact Arm
Asm,

24, Cup Bearing
2S* Booster
Tube
26* Front Vertical
Barrier
27!

12. Front Bushing
13. Rear Bushing

20!

Check Nut
Connection Bar

15. I4ain Operating Crank

30!

Booster Cylinder & Piston

14. lft)per Horizontal Barrier 29!

Side Barrier

Pig, 8 Cross Section of Breaker
Pole unit

GEI-88762

^g. 9 Adjustable Coupling
for Making Primary Contact

wipe Adjustments

1. Operating Rod
2. Operating Rod Pin
3. Adjusting Nut
Check Nut

5. Stationary Primary Contact
o. Movable Primary Contacts

7. Contact Arm
8. Yoke

Pig. 10

Positive Inter

lock Switch

1. Positive Interlock Switch
2. Sv/itch Arm

3. Interlock Switch
Switch Support
5. Auxiliary Switch
D. Switch Support

7. Latch Checking Switch
o. Switch Arm

9. Trip Shaft

(4^

GEI-88762

Fig, 11 Auxiliary
Svrltch and Trip Coil
1. Trip Coll Support
2.
3.
4.
5.

Trip Coll
Mounting Bolts
Counter
Trip Latch '

6. Trip Arm Screw
7. I-Ianual Trip Lever
8. Open-Close Indicator
9. Auxiliary Switch
10. Switch Arm
11. Latch Set Screw
12. Cotter Pin

13. Prop Spring

Latch Checldng
Switch

1. Sv^itch- Support

2. Latch Checking Switch

3. Sv/itch Arm

4. Trip Latch
5. Reset Pin Stop
6. Latch Roller
7. Latch Roller Llnlc

8. Latch Roller Pin

GEI-88762

; 1. Plunger Bolt

,! 2. Washer
i 3. Breaker Lifting Rail

Pig. 13

Plunger Interlock

1. Mounting Bolts
2. Eccentric

3. Hex Charging Stud
4. Fuse
5. Manual Close Button
D,

Motor

7. Retaining Ring

8. Motor Support

9. Retaining Ring
10. Driving link

Fig. 14 Driving Elements

Ui£I-Oa7b2

Rear Bushing
lft)per Insulation
Coil Support
Assembly Bolts
Assembly Bolts
Assembly Bolt
Spring Retainer
Assembly Bolts

Contact Springs
Coil Protector

Glass Bonded Mica Side Piece
Blow Out-Coil
Arc Runner

Blow Out Coil
Arc Runner
Contact Braid

Blow Out Coil
Arc Runner

Stationary Arcing Contact
Stationary Primary Contacts
Core

•H. Coil Svqjport
)acer

-exible Lead

Fig. 15 Disassembly of l^jper Arc Runner lAiit

GEI-88762

Pjpper Assembly Bolts
Lower Assembly Bolts
yfc>per Pole Pieces
Lower Pole Pieces
Assembly Bolts

^0 Chute,, jjpper Half
Pole Piece Bolts

Pole Piece Core Bolts
Bolts

Chute, Lower Half
Nuts
Nut

Pig. 16 Arc Chute Assembly

Lower Runner Support

Insulation (Cover)

Blow-out Coil Cores
Spacers

Coll Connection

Lower Runner Assembly
^per Runner Support Spacer
^siilating- Tube for Core

Blow-out Colls

Assembly
with Side Removed

GEI-88762

-M

Pig. 18 Arc Chute Partially Removed Showing Accessibility of
Arcing Contacts
1.
2.

3.
4.

Spacing

ftour.-j

Stud, Lower Supporting Bolt

c Runner ifiilt

Mounting Bolts

i;
I:

Support Bracket
Arcing Contact

10.

Pig. 19 Arc Chute Fin

Hear ~-'shing
Suppo
ig Bolt

Arc Runner

Horizontal Barriers
Primary Contacts

11.
12.

Contact Arm.

13.

Arc Chute Lifter Bolt

14. Handle
Trolly
16. Arc Chute Lifter
17. Grappling Hooks
18. Pole Pieces
19. Arc Chute Assembly
20.
21.
22.

Plastisol Flexible Cover
Lifting Supports
Angle Support

GEI-88762

1. Crank

2. Arc Chute Lifter
3. Support Catches
4. Arc Chute

5. Mounting stud

Pig. 20

Method of Removing

the Arc Chute

Lower Horizontal Barrier
Spring Retainer.

Contact Springs
Primary Contacts
Contact Am

Primary Contacts
Assembly Bolts
Assembly Bolts
Arcing Contact
Front Bushing
Pin

CiQj Bearing
Connection Bar

Tertiary Contact Fingers
Contact Spring
Piston Assembly
Booster Cylinder

Pig. 21 Removal of Contacts

GEI-88762

PART

iLUBRICATION AT
MAINTENANCE
PERIOD

Sleeve Bearings - Links,

trip shaft, etc. (Teflon
coated bearings)

INo lubrication
required.

Sleeve Bearings - main crank Light applica
shaft, driving pawl lever.
tion of machine
(Bronze or cast iron)
Ioil SAE 20 or
SAE 30.

^TERNATE LUBRICATION

(REQUIRES DISASS04BLY)

No lubrication required.

Remove bearings or
links, clean per in

structions and apply
DSOHIS lubricant liber

ally.

Contact Arm Hinge Assembly

CxQ) Bearing

Loose rings between bushing

No lubrication

Wipe clean and apply

required.

D50H47

and contact arm.

Roller and Needle Bearings

Ground surfaces such as
cams, ratchet teeth, etc.

(Surfaces coated with I^Sg)

Ground surfaces such as

latches, rollers, prop, etc
Silver plated contacts and

primary disconnect studs
Booster Cylinder

Light Applica

and repack with DSOHIS

No lubrication

No lubrication required

required.

Lubricant.

Wipe clean
apply D50H1,
lubricant.

D50H15 lubricsuit

Wipe clean and

Wipe clean and apply

apply D50H47
Do not

lubricate.

Arcing Contacts

Clean per instructions

tion of machine
oil SAE 20 or
SAE 30.

Do not

Wipe clean and apply

P50H47
Do not lubricate

Do not lubricate

lubricate.

Fig. 22
46

LUBRICATION CHART

GEI-88762

ns. S3 Method Of Installing Primary Contact Springs
Using a Spring Compressor

1. Spring Guide
2. Compressor Nut

3« Spring Compressor
Spring Retainer
5. Assembly Bolts

6, ^rlng
7» Contact Support

8. Stop Plate

9. Stationary Primary
Finger

INSTRUCTIONS

GEK-7320F
rsedes
GEK-73ZOE
Supe

MAG NE BLAST CIRCUIT BREAKER··
TYPES
'

,;/

!�

AM-4.16-350-2C
AM-4.16-350-2H

r-·

.,:-

CONTENTS

. . .

"'...

Introduction

Receiving, Handling
and Storage

Installation

:�

·'

•>

. . . . .

Description of Operation

(

Adjustments

. . . . . .

General Maintenance
Renewal Parts

(

. . .

.4
10
.14

GENERALfj ELECTRIC

MAGNE-BLAST

CIRCUIT

BREAKER

AiVi-4.16-350-2 (^)
^

Letter Designation C, and H, used immediately following the model number indicates basic
•design features.

INTRODUCTION
The magne-blast breaker is the removable and

interchangeable interrupting element used in metal-

clad swltchgear to provide reliable control andpro
tection of electrical apparatus and power system:;.
The AM-4.16-350 Magne-blast Breaker is avail -

abl? withcontinuous current ratings of 1200 amperes
and 3000 amperes in accordance with applicable
industry standards.

Refer to the breaker nams-

plate for complete rating information of any par

age, current, and internipting ratings are never
exceeded.

Since this book is written to include

all rat^s of the breaker as well as several design
variations, the instructions will be of a general
character and all illustrations will be typical unless
otherwise specified.
PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SAT
ISFACTORY OPERATION OF THE BREAKER. The

ticular breaker. The nameplate also describes the
control power requiremants for that breaker. The

following instructions will provide complete infor

application of a breaker must be such that its volt

and for maintaining satisfacotry operation.

mation for placii^ magne-blast breakers in service

RECEIVING, HANDLING AND STORAGE
Receiving and Handling

gainst condensation, preferably by stor
ing it in a warm dry room, since water
absorption has an adverse effect on the
insulation parts.
Circuit breakers for
out-door metal-clad swltchgear should be
stored in the equipment only when power
is available and the heaters are in oper
ation to prevent condensation.

Each breaker is carefully inspected and packed
for shipment. Immediately upon receipt of the
circuit breaker, and examination should be made

for any damage sustained in transit. If injury or

rough handling is evident, a damage claim should
be filed immediately with the transportation com

pany and the nearest General Electric Sales Office
should be notified.

during the unpacking and installation of the breaker
so that no damage will occur from careless or

rough handling, or from exposure to moisture or
dirt. Check all parts against the packing list to be

sure that no parts have been overlooked.

Unfinished surfaces of rollers, latches,
etc., of the operating mechanism should be

Storage

coated with grease to prevent rusting.

It. is recommended that the breaker be put into

service immediately in its permanent location. If
tois is not possible, the following precautions must
be taken to insure the proper storage of the breaker;

The breaker should be stored in a clean

location, free from corrosive gases or
fumes; particular care should be taken to
protect the equipment from moisture and
cement dust, as this combination has a
very corrosive effect on many parts.

It is expected that due care will be exercised

The breaker should be carefully protected

If the breaker is stored for any length of time,
it should be inspected periodically to see that
rasting has not started and to insure good mechan
ical condition. Should the breaker be stored under

unfavorable

atmospheric

conditions,

it /hould

be cleaned and dried out before being placed
in service.

(Cover Photo 8035726)
purport to cover all details or variations in equipment nor to provide for
conti/ifffiTJCv CO be met in connection with installation, operation or maintenance. Should

turtner information be desired or should particular problems arise which are not covered sufficiently for
cne purchaser s purposes, the matter should be referred to the General Electric Company.
products described .herein meet applicable ANSI,

IEEE and NEMA standards:

out no such assurance is given with respect to local codes and ordinances because they vary greatly.

GEK-7320 Magne-blast Circuit Breaker
INSTALLATION
BEEN TRIPPED OPEN OR MECHAXIPAt t

Each breaker has been tested and inspected
before shipment from the factory: however, before
placing the breaker in service the following items
should be checked to assure that no change has oc -

BLOCKED. THIS PRECAUTION IS REQL'^^^^^^

PREVENT ACCIDENTAL CLOSING OR TRIPPIN

curred during shipment and storage.

The closing springs should now be unblocked Ro

1. Remove the box barriers and mechanism cover

icSAR^pn-*"5
indicatorVe'
ac
charged and fK
the ratchet wheel does
not advance

and make a visual inspection to ascertain that the

Check®satisfactory condition,
lubrication
mechanism for

16 aid

lubrication page

The spring blocking device can now be removec
3. To assure that the electrical connection

have remained tight, they should be checked durir..
installation as well as during each maintenance in

spection. This check of electrical connectiinsl

manually

using a 5/8 ratchet wrench to turn the drivine ec-

centric (6) Fignrel. Terning the eccentric coeCerss

press the springs.

When the springs have reached the fully chareed
position the indicator (1) will read "CHARGED-' Sd
^eel teeth. Additional turningoi the eccentric will

particularly necessary on breakers used in nuc'eaand other critical applications^
The bolted braid connections on the stationary arcine
contacts should bechecked for tightness bv remonnthe arc chutes as described on page 15.'

4. Connect the test coupler to the circuit breakeand operate it electrically several times. Check

the control voltage as described under "CONTROi

not advance the ratchet wheel.

POWER CHECK" (Page 14).

dSr«
blocking
device
andbvmanually
discharge the springs
against
the (9)pins
oushinc

5. Disconnect the test coupler and before -eoiac- •
the box barrier, the primary bushings and othv"

the manual release button (4). The spnngi are now
blocked and slow closingof the breaker contacts can
be accomplished by again turning the driving eccen

tric With a 5/8" ratchet wrench

insure
that the mechanism does operation
not stick check
or bindto durui"
the entire stroke, that it latches securely in the
closed position, and that it trips treelv when thi
manual trip lever is operated. Aithis time, also

check the following adjustments:

a. Arcing contact wipe (Refer to oage 10)

o. Primary contact wipe (Refer to page 10)
c. Primary contact gap (Refer to page 10)
DO NOT WORK ON EITHER THE BREAKER OR

mechanism unless the closing sprigs ^ r

BLOCKED AND THE OPENING SPRING HA^E

insulation should be wiped clean.

6. If the breaker has been stored for a Ion-' pe-od

oi time. It is recommended that the insulation liv

checked i^th astandard 60 hertz high potential test

Reier to Insulation Test (Page 16).

II the breaker secondary wirirp to
a hi-potential test at 1500 volts re-wvo

bu-:;
.notor leads from the terminal connecfon
Faun;-.- to disconnect the motor from the circ-n
may cause damage to the winding insulation.

7. Lubricate the silver portion of the ball coivac

at the top of the breaker bushing and the rear aor tion of the ground shoe, by applying a thin .iln: o;
contact lubricant D50H47.

3. Refer to metal-clad instruction book GEH-ISC^

lor instructions on inserting the breaker in'o -x'
metal-clad unit.

description of operation
The magne-blast breaker has twniirMn imi

Sis.?.'
mam and arcing contacts, mter-jnrer

enclosing barrier system ^hat :irovSrK,.Xiu;:
4

• Indicates revrsion

between poles, or phases and to ground. The ar--

to the associated metaf-i-i I'ci

^.witchgear are made through the bail contact- u
the top of the breaker bushings.
mechanism tvpe .ML-13 is of -he

rin
"to irive wiiropeJate
high -ue- i
closing
and opening. designed
The mechanism

Magne-blast Circuit Breaker GEK-7320

Figure 1. (8040407) Spring Blocking Device
1.
2.
3.

Charge-Discharge Indicator
Support Bolts
Driving Pawl

Manual Close Lever

5.
6.

Motor
Eccentric

7.
8.

Closing Spring
Manual Charging Wrench

Spring Blocking Device

Mi-

Figure 2. (8034473) Left Side View ML-I3
Operating Mechanism

Figure 3. (8038805) Spring Discharge Linkage
1-

Link

2.
3.
4.
5.

Adjusting Bolt
Trip Latch Crank
Discharge Crank
Adjusting Clevis

Spring Release Crank

Secondary Coupler

Interlock Switches

Auxiliary Switch

Latch Checking Switch

Switch Cam

6.
7.

Charge-Discharge Indicator
Closing Latch Roller

Power Switches

9.
10.

Closing Latch
Closing Springs

11.
12.

Motor
Fuses

Ui::K-7320 Magne-biast Circuit Breaicer

V- m
Figure 5. (8034471) Front View ML-:3
Operating Mechanism
1. Auxiliary Switch

2. Open - Close Indicator

1.%

3. Trip Coil

4. Prop Spring

;4io/j

5. Operation Counter
6. Trip Latch

7. Charge-Discharge Indicator

Figure 4. (8040405) Right Side View ML-13

8. Manual Trip Lever
9. Manual Close Lever

Operating Mechanism

2'; Positive
SfcWnTpaJls'
" Roller l9. Lowe^^Snrin^
§"'•">= BlockP
3.
Interlock
5;
6.

;?•^ rf.""'"?
?-mgTa;"fi!e;\i

Ratchet Wheel

i'i- Closing Spring

nJmep'a^e.

°"

Motor

•M-,en Che breaker is not in either the fullor lowered position. To insure th-.f 7hfo •"

•vill function during manual as 'well

electrical operation%f the equipment both

anical and electrical blocking is prodded"

fm-

charged against the positive interlock- tho

any reason the closing springs should ho

i!J"~

clad unit are made thr.mgh ihe ••oupler''n

force to release the interlock.

to ^isSarfe

" "''

^"^^'•^°^kmounred.n,hemeS:;

A positive interlock 3i F-mre j . .
switch (2) Fi1^

Vi/

Y
I

-J

Y
(0165B7906)

FIG. NO.

REF. NO.

DESCRIPTION

AUXILIARY SWITCH

AUX SW

52X

CLOSING COIL

52Y

CONTROL RELAY

52
TRIP COIL

INTERLOCK SWITCHES

IS
52

CL/MS

CLOSING LATCH MONITORING
SWITCH

52
LC

LATCH CHECKING SWITCH

7^,
MOTOR

SPRING CHARGING MOTOR

GEK-7320 Magne-blast Circuit Breaker
RECOMMENDED RENEWAL PARTS FOR MAGNEBLAST BREAKERS

TYPE AM-4.16-350-2

(♦)

1200 & 3000 AMPERE

(• SUFFK LETTERS H, C, R)

Fig.
No.

Ref.
No.

8
a
22
22
22
22
22

16
16

22
24
24
24
24

10
6
6
9
9

23
23
23
23
23
23
23
23
23
23
20
20

17
10
10
10
10
18
15
15
13
13
4
4
10
2

7
7
7
7

Ampere
Rating
1200

3000
ALL
ALL
ALL
ALL
ALL
ALL
1200

3000
1200
3000
3000
1200
1200
3000
3000
3000
1200
3000
1200
3000
ALL
ALL
ALL
ALL
ALL
ALL

Catalog No.
0281B0708G008
0802B0730G001
0208A8017G001
0208A8017G002
0208A8017G003
0208A8017G004
0208A8016G001
0213X0344G032
0121A5964P001
0414A0180P001
0114C5382P002
0114C5382P002
0114C5382P002
0137A9164P005
0137A9164P006
0114C5382P011
0114C5382P012
0619C0469P003
0227A5306G001
0227A5306G002
0213X0343G094
0132C2748G003

0134C3595G001
0134C3595G002
0132C2735P007

0108B5520P001
0265C0163P009
0421A0201P001

No.

Req'd
3
3
3
3
3
3
3
3
24
36
24
36
12
6

6
6
6
6
3
3
3
3
3
3
6
3
6
6

Description

Operating Rod Assembly
Operating Rod Assembly

Flexible Connector (Left, Long)

Flexible Connector (Right, Long)
Flexible Connector (Left, Short)

Flexible Connector (Right, Short)
Throat Barrier Assembly
Arcing Contact Assembly
Primary Contact Finger Spring

•Primary Contact Finger ^ring

Primary Contact Finger
Primary Contact Finger
Tertiary Contact Finger
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Tertiary Contact
Movable Arcing Contact
Movable Arcing Contact
Tube & Piston Assembly
Tube & Piston Assembly
Throat Cooler Assembly (Right)
Throat CoolerAssembly (Left)

Lower Runner Barrier
Insulation Plate

Upper Runner Insiilation,
Lower Runner Shield

<|) Not Illustrated

INSTRUCTIONS
GEI-88771 D

Supersedes GEI-88771 C

MAGNE-BLAST CIRCUIT BREAKER

,.*,TYPE
AIVIH-4.76-250-0D

AMH-4.76-250-1D

V-.'

GENERAL^ ELECTRIC

MAGNE-BLAST

CIRCUIT

AMH-4.76-250-0D

BREAKER

AMH-4.76-250-lD

INTRODUCTION
The magneblast breaker Is the removable and

interchangeable interrupting elementused in metalclad swltchgear to provide reliable control and pro
tection of electrical apparatus and power systems.
The AMH-4.76-250 Magneblast Breaker Is avail
able with continuous current ratings of 1200 amperes
and 2000 amperes In accordance with applicable
industry standards. Refer to the breaker nameplate for complete rating information of any par
ticular breaker. The nameplate also describes the
control power reauirements for that breaker. The
application of a breaker must be such that its volt

age, current, and interrupting ratings are never
exceeded. Since this book is written to include

all ratings of the breaker as wellas several design

variations, the instructions will be of a generM
character and all illustrations will be typical unless
otherwise specified. •
PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SAT
ISFACTORY OPERATION OF THE BREAKER. The

following instructions will provide complete infor

mation for placing magne-blast breakers in service
and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
Receiving and Handling

against condensation, preferably by storing
it in a warm dry room, since water at>sorp-

Each breaker is carefully inspected and packed,
for shipment. Immediately upon receipt of the
circuit breaker, an examination should be made
for any damage sustained in transit. If injury or
rmigh handling is evident, a damage claim should
be filed immediately with the transportation com

tion

pany and the nearest General Electric Sales Office
should be notified.

It is e^qpected Biat due care will be exercised
during the uiqiacklng and installation of the breaker
so that no damage will occur from careless or
rough handling, or from exposure to moisture or
dirt. Check aU parts against the packing list to be
sure that no parts have been overlooked.
Storage

It is recommended that the breaker be put into
service immediately in its permanent location. If

this is not possible, the following precautions must

be t^en toinsure theproper storage ofthe breaker:
1.

The breaker should be carefully protected

has

adverse

effect

on the

sulation parts. Circuit breakers (or ou
door metal-clad switchgear should be store,
in the equipment only when power is avai
able and the heaters are in operauon'
prevent condensation.
2.

The breaker should be stored in a clean

location, free from corrosive gaaee or
fumes; particular care should be taken to
protect the equipment from moisture and
cement dust, as this combination has a very
corrosive effect on many parts.
3.

Unfinished surfaces of rollers, latches etc
of the operating mechanism should be roeted
with grease to prevent rusting.

If the breaker is stored for any length at tm*.
it should be inspected periodically to see 'hat
rusting has not started and to insure good me^hanical condition. Should the breaker be stored under

unfavorable atmospheric conditions, it Bhaaa >>•
cleaned and dried out before being placed la

(Cover photo

T/Mn instructioM do not purport to cover «Ji deuiJr or varJatiena in a^ulptiont nor to provide
every possiblofeantingency -to be aot in connoetion tritb Installation, oporation or maintanancm.
imm.v
tuxtbor infematien be desired or should perticuier proPJens arise which are not covered sufficient,$

the purcAeeer'e piirpoaee, the Batter should be referred to the General Electric Conpany.
To the extent required the products described herein meet applicable AHSZ,

ZEES and NEMA sta

Pue no such assurance is given with respect to ioceJ codes and ordinances because the*/ vary gpeatls

GEI*d8771 Magne Blast Circuit Breaker

INSTALLATION
1.

Remove the top cover and box barrier.
Do not remove side or front covers. (See
note under Repair and Replacement, page
22.) Make a visual inspection to ascertain

SPRINGS ARE BLOCKED AND THE OPEN
ING SPRINGS HAVE BEEN TRIPPED OPEN
OR MECHANICALLY BLOCKED.
THIS

that the breaker and mechanism is in satis

ACCIDENTAL

factory condition.

PRECAUTION IS REQUIRED TO PREVENT

Check all bearing sur

faces of the mechanism for lubrication.

ratchet wheel does not advance. The spring
blocking devices can now be removed.

ually using a 5/8" ratchet wrench to turn
the manual charging shaft (3) Figure 1.

position. Operate it electrically several
times. Check the control voltage as de

When the springs have reached the fully
charged position the indicator (5) Figure

scribed under"CONTROL POWER CHECK"

(Page 16).

2 will read "CHARGED", and the driving
4.

Disconnect the test coiq>ler, or remove
breaker from housing, and replace box
barrier and top cover.

If the breaker has been stored for a long
period of time, it is recommended that

shaft will not advance the ratchet wheel.

Insert the spring blocking devices into
a hole (2) Figure 1 on each side of breaker,
and manually discharge the springs against

the insulation be checked with a standard

the pins by pushing the manual close

button (6) Figure 2.

60 Hertz high potential test.
Insulation Test (Page 18).

The springs are now

blocked and slow closing of the breaker
contacts can be accomplished by again
turning the manual charging shaft with
a 5/8" ratchet wrench.

NOTE:

Arcing contact wipe (Refer to page 12).
Primary contactwipe (Refer to page 13).
Primary contact g^ (Refer to page 13).

DO NOT WORK ON EITHERTHE BREAKER
OR MECHANISM UNLESS THE CLOSING

If the breaker secondary wiring

volts, remove both the motor leads from
the terminal connection.

Failure to dis

connect the motor from the circuit may

insure that the mechanism does not stick

a.
b.
c.

Refer to

is to be give^ a hi-potential test at 1500

During the slow closing operation check to

or bind during the entire stroke, that it
latches securely in the closed position, and
that it trips freely when the manual trip
lever is operated. At this time, also check
the following adjustments:

Connect the test coiqpler to the right hand
secondary coupler or insert the breaker
into the metalclad housing to the test

advance the ratchet wheel and congiress
the springs.

pawl will be raised from the ratchet wheel
teeth. Additional turning of the charging

TRIPPING.

the indicator reads "CHARGED" and the

Charge the breaker closing springs man
Turning the shaft counter clockwise will

The closing springs should now be un
blocked.
Rotate the charging shaft until

Refer to section on lubrication page 18
and Figure 16.
2.

CLOSING

cause damage to the winding insulation.

Lubricate the inside silver portion of the
primary disconnect fingers by applying
a

thin film of contact lubricant D50H47.

The lubricant should extend aig>roximately
one inch (1") from the end of the finger.
7.

Refer to metal-clad instruction book GEI-

88775 for

instructions on inserting the

breaker into the metal-clad unit.

DESCRIPTION OF OPERATION
The Magneblast Breaker has two principal com
ponents; the breaker element and the operating

tee stored energy type designed to give high

mechanism:

on a-c or d-c voltage as indicated on tee brveker
nameplate. Closing and opening operatloos 4re
controlled either electrically from the metal-<• us
unit and remote location, or mechanically bv um
manual close and trip buttons on tee breaker, au

The breaker element is three similar pole units,
each of which includes tee current carrying parts,

main and arcing contects, interrupter, and an
enclosing barrier system that provides insulation

between poles, or phases and to ground. The pri-

_ mary connections to tee associated metal-clad

/"^switchgear are made through tee primary disconnect fingers at tee rear of tee breaker.

The operating mechanism type ML-13A is of

closing and opening. The mechanism will operete

second^ connections from tee breaker to the

clad unit are made through the coupler (1) ftg* iA spring release interlock. Fig. 4 is pi
to discharge both tee closing and opening •pnegs
when the breaker is vdthdrawn from or u
into tee Metal Clad unit.

Fig. 1 (8037382) Manual Charging
1.

987634

Fig. 2 (8037380) Control Panel

Manual Charging Wrench

Hole for Spring Blocking Pin

Trip Button

Position Indicator

Bevel Gears

Closing Spring

3.
4.
5.

Racking Screw Shutter
Position Stop Release
Charge-Discbarge Indicator

Manual Charging Shaft

Close Button

7.
8.
9.

Open-Close Indicitor
Operation Counter
Racking Screw Hole

10.

Padlock Hole Cover

11.

Hand-Charge Hole Cover

1. Secondary Coupler
2. Interlock Switches

3. Auxiliary Switch

4. Latch Checking Switc h
5. Spring Discharge Roiisr

6. Switch Cam

7. Closing Latch RoUer
6. Closing Latch
9. Power Switches

10. Closing Spring
11. Motor

12. Control Relay

13. Spring Blocking Pis

8 7

Fig. 3 (8037375) Right Side View ML-13A Operating Mechanism

GETiii8?7l Magne Blast Circuit Breaker

Spr^ Discharge Stop
Spr^ Discharge Roller
Spring Discharge Crank

IXim^ckle
Closing Latch Stop
Spring Discharge Stop
Trip Link
Closing Latch Roller
Switch Cam
Switch Striker

Switch Support Bolt
Switch Support
Power Switches

Closing Latch
Switch Support Bolt
Motor Terminal Board

Clos^ Latch Shaft
Closing Latch Spring
Motor

Latch Monitoring Switch
Latch Switch Support

Sprii^ Release Solenoid
Closii^ Coil Support

23 22 21 201918 17 16 15 1413 12 11

Fig. 4 (8037379) Control Mechanism and Spring Discharge Link

3 4 5

6 7

8 9

Fig. 5 (8037377) Left Side View ML-13A Operating Mechanism
1. Main Shaft Bearing
2. Rear Spring Pin
3. Latching Pawls
4. Positive Interlock Roller

5. Opening Spring
6. Cam Shaft

7. Ratchet Wheel
8. Guide Block

9. Front Spring Pin
10.

Eccentric

11. Closing Spring

Magn® Blast Circuit Breaker GEI-68771
Aposltive interlock (4) Figure 5 and interlock
switch (2) Figure 3, are provided between the
breaker and metal-clad unit and work with the
rack screw shutter to prevent insertion or re
moval oi the breaker in the unit while in a closed

position and to prevent a closing operation when the

breaker is not in either the fully connected or
test position. To insure that this interlock will
function during manual, as well as during electrical
operation of the equipment, both mechanical and

electrical blocking is provided. If for any reason
the closing springs should be discharged against
the positive interlock the mechanism will be
jammed and be inoperable. The mechanism can
be released and returned to the reset position
by pushing in on the trip lever (1) Figure 2. It
may require more than normal force to release
the interlock.

An auxiliary switch operator (3) Figure 6
can be provided when required to operate a
stationary auxiliary switch mounted In the metal
clad unit.

The pawl advances the ratchet wheel (7) Figu- .
5 a few degrees' each stroke where it is held
position by the latching pawls (3). When the ratchet

wheel has been rotated approximately 10Q degre
the closing springs (11) will be fully compresse.

As the ratchet wheel continues to rotate, the spring
load will shift over centerandatterapttodischarge.

After a few degrees of rotation, the closing roller
(7) Figure 3, will engage the closing latch(8) and
the compressed springs will be held by the latch
until a closing operation is required. During the
last few degrees of the ratchet wheel rotation the

power switches (9) are opened and the drivingpawi
is raised from the ratchet wheel surface. This
allows the motor and driving mechanism to coast
to a natural stop expending all residual energy.

During the time the springs are being compressed
a relay (12) is energized to hold the closing circuit
open. The relay remains energizeduntil the springs
are fully charged and the control s'witch contacts
are re-set.

The closing springs may be charged manually
if control voltage is lost. A 5/8" ratchet wrench
can be used to rotate the manual charging shaft

The mechanism has a high speed gear motor (1)
Figure 7, that compresses a set of closing springs
through the action of an eccentric, ratchet, and
pawl assembly. The rotary action of the motor
is converted to astraightstroke through the eccen
tric (5), and a lever (6) that carries a spring loaded
driving pawl.

in a

counter clockwise direction until the indi

cator reads "Charged" and the driving pawl 13
raised from the

ratchet wheel.

The use of the

ratchet wrench provides for maximum safety
in the event that the control power Is suddenly
restored without warning. In this event, the motor
drive will override the ratchet wrench and con

tinues to charge the springs.

i
-

ciS' •'
^43

Fig. 6 (8037376) Auxiliary Switch Operator

1. Spring Discharge Crank

Moimting Bolts

3.
4.

Auxiliary Switch Operator

Mounting Bolts

5, Secondary Dlsconner*
6.

Treadle Link

GEI- 88771 Magne Blast Circuit Breaker

m-J
1.

Motor

2. Mounti^ Bolt
3. Retaining Ring
4. Motor Mount
5. Eccentric

6. Driving Link

^^6

Fig. 7 (8037378) Driving Elements)

the opening springs is released to provide the
The breaker can be closed electrically by
energizing the spring release solenoid (22) Figure
4, or manually by pushing the close button (6)
Figure 2. In either method the closing latch is
rotated from under the closing roller to release
the closing spidngs (10) Figure 3. The energy
in the springs is used to rotate a cam (16) Figure
8 and close the breaker through the operating
mechanism linkage. During the closing operation
the mechanism istrip-freeatalltimes. The break
er is held closed by the closing prop (14) moving
into position under the prop pin (13). During the
closing operation the opening springs (17) Figure 9,
are compressed and held ready for an opening
operation with the trip latch (8) Figure 8 bearing
against the trip latch roller (9).

required opening speed for successfxil ^terrupucn

of Uie circuit.

As the breaker opens to interrupt a current, the
arc first starts at the arcing contacts (6 4 271
Figure 10, transfers to the arc runner (4 & 10) and

energizes the blow-out coils (3 4 11). This action
introduces a magnetic field between the pole piecee
5 & 9) of the interrupter that forces the arc deeper
into the arc chute (8^ At the time the arcing ctmtacts part a discharge of air is expelled ihrouch
the booster tube (28) across the arc. This air
flow assists the arc transfer and interruptian cr*
blowing the arc away from the contacts and mni
the arc chute. The magnetic field forces the ar-r
deeper into the interrupter along the divergmt ar'
runners.

The arc chute has a series of interleavu^ r *r -

When the closing operation of the breaker is

amic fins, Figure 18. As the arc is forced laao law

the contacts of the latch monitoring switch (20)
Figure 4, closes to permit the spring charging
motor to be energized and recharge the closing

interrupter it is lengthened in the graduailT leap
ening serpentine path between the fins so tnat
electrical resistance of the arc is rapidly inc raaaae
and its heat Is absorbed by the ceramic mstenu

completed and the closing latch is fully reset,

springs.
Opening Operation

The increased resistance reduces the

The breaker can be opened either electrically
»y energizing the trip coil (13) Figure 9, or man/•^ally by pushing the trip lever (1) Figure 2.
» each method the trip latch is rotated off the
- crip latch roller, permitting the operating mech
anism linkage to collapse. The energy stored in

and phase angle of the current and at a>
current zero the arc cannot re-establisfe

and interruption occurs.
Trip Free Operation

If the trip coil circuit is energized
tm
breaker is closing, the trip armature wui •
the trip latch (8) Figure 8 away from ttm "p

Magne Blast Circuit Breaker GEI-88771

roller (9) causingthe mechanism linkage to coUajpse

will coihplete its closing stroke and the springs

will re-charge as in a normal closing operation-^

and the breaker to re-open. The closing cam (16)

16 25 15

iO 9

2.
3.
4.

Fig. 8 (0121C8152) sectional Side View of Mechanism
17. Check Nut
Frame
9. Trip Latch Roller
18. Stop Plate
Trip CdU Support
10. Trip Latch Roller Support

Trip Coil
Trip Armature
Prop Reset Spring

11. Crank Shaft
12. Cranks
13. Prop Pin

Cam Follower Roller

14.

7.
8.

Trip Shaft
Trip Latch

15. Drive Shaft
16. Cam

Prop

19. Spring Rod
20. Spring

21. Spring
22. Spring Guide

23. Stop Pin
24. Main Shaft Beanna
25. Cam Shaft Beartna

GEI-88771 Magne Blast Circuit Breaker

Fig, 9 (8037378) Bottom View of ML-13A Operating Mechanism
Secondary Disconnect

Trip AdjQstlng Nut
Manual Trip Lever
Auxiliary Switch
Latch Check Switch

Latch Check Switch Arm

Prop Spring
Auxiliary Switch Link

Trip Coil

Trip Latch Spring

Trip Coll Support

Latch Set Screw

Trip Latch

Trip Coil Support

Trip Arm Screw

Coil Moimting Bolts
Opening Springs
secondary Disconnect

Magne Blast Circuit Breaker GEI-88771

•2

II 0

30 29

28 27 26 25

24 23 22

17 16

15 14

Fig. 10 (0121C8153) Cross Section of Breaker Pole Unit
1.
2.

Upper Bushing
Blow-out Core

3.
4.
5.

Blow-out Coil
Arc Runner
Pole Piece

Stationary Arcing Contact

7.
8.
9.

Box Barrier
Arc Chute
Pole Piece

10.

Arc Runner

11. Blow-out Coil
12. Blow-out Core

13. Disconnect Fingers
14. Lower Frame

21. Operating Rod
22. Stationary Primary Contacts
23. Movable Primary Contacts
24. Cup Bearing

15. Lower Bushings

25.

16. Frame

26. Movable Contact Arm Asssmblir
27. Movable Arcing Contact
28. Booster Tube
29. Connection Bar
30. Booster Cylinder and Piston

17. Operating Crank
18. Rear Vertical Barrier
19. Spring Retainer
20. Lower Vertical Barrier

Yoke

OEI»88771 M^gne Blast Circuit Breaker

ADJUSTMENTS
All adjustments should be checked during periodic inspections and whenever it becomes nec
essary to repair or rrolace parts that have become
worn or defective while in service. The following
adjustments are listed in the order in which they
are to be checked after removing the top cover
and b(« barrier from the breaker.
DO NOT WORK ON EITHER THE BREAKER OR
MECHANISM UNLESS THE CLOSING SPRINGS ARE
BLOCKED AND THE OPENING SPRINGS HAVE
BEEN TRIPPED OPEN
OR
MECHANICALLY

BLOCKED.

Arcing Contact Wipe

Refer to Figure 11. Close the breaker until
the arcing contacts just touch.
This can be
determined with the use of a circuit continuity
tester such as a light indicator or bell set. In
this position, the gap between the stationary primary

contacts (1) and the movable primary contact (2)

should be .5/16" or greater. T^ setting has been

Primary Contact Wipe
Figure llA.

THIS MEASURE IS REQUIRED TO

PREVENT ACCIDENTAL CLOSING OR TRIPPING.

Arcing Contact Wipe
OD" Contact Structure (0121C8152)

7564
Primary^ontact Wipe

Arcing Contact Wipe

Figure lie "-ID" Contact Structure (0132C2794)
Figure II Contact Adjustments

1. Stationary Primary Contacts

6. Contact Arm

3. Buffer Block

7. Throat Baffle

4. Stationary Arcing Contacts
12

5. Movable Arcing Contacts

2. Movable Primary Contacts

Magoe Blast Circuit Breaker GEI-6d771

made in the factory and no adjustment is provided.

A wipe of less than 5/16" is an indication that the

arcing contacts need to be replaced. When making
this check, see that the mov^le arcing contact
passes between the probes on the upper arc runner

without touching. On the "-ID" des^, also check

for clearance between the arcing contact (5) and
the slot in the throat baffle (7) during entire stroke
of the moving contact assembly.
Primary Contact Wipe

Refer to Figure 11, when the breaker is closed
the stationary primary contacts (1) should rise
from 1/4" to 5/16", Before checking this dimen-

sion be sure the mechanism is re-set so that

the prop pin (13) Figure 8 is resting on the prop. '
To obtain the proper contact adJiStment, open
the breaker and, referring to Figure 12, loosenthe
check nut (13)and turn the adjusting nut(12). Screw-

^ the adjusting nut toward the operating rod
(11) will decrease the primary contactwipe, toward
the end of the stud (14) will increase it. Tighten
the check nut, close the breaker and recheck

the wipe.

With the primary contact wipe cor

rectly adjusted, the clearance between the contact

arm (6) Figure 11 and the buffer block (3) should

be 1/18" or greater when the breaker is fully
olosed.

Primary Contact Gap

Refer to Figure 12. With the breaker closed,
press the manual trip button allowing the breaker to
trip open normally.

Do not force the contacts

open wider by hand. The gap between the stationary
primary contacts (4) and the movable primary con
tact (6) measured between the closest points, should

be 3-5/8" to 3-15/16". To change this gap, loosen

the check nut (17), Figure 8, and turn the adjusting
nut (18) on stud (19). Screwing the adjusting nut
down will decrease the primary contact gap.
Tighten the check nut and re-measure the contact

gap (close and trip the breaker before checking
the measurement). Whenever the primary r.-ntact
gap is changed, the primary contact wipe should
be rechecked and, if necessary, readjusted,
WHEN WORKING ON THE MECHANISM IN THE

CLOSED POSITION, KEEP FINGERS CLEAR OF --v
THE LINKAGE, AS ACCIDENTAL TRIPPING CA.N
CAUSE SEVERE INJURY.
Trip Latch Wipe

Refer to Figure 8. The wipe of the trip latch
(8) on the trip roller (9) should be from 3/lfl"

to 1/4". This can be measured by putting a fUm
of grease on the latch (8), closing the breaker
part way, and tripping. The mechanism has th#
proper trip latch wipe when the latch rests agaiaet

the stop pin (23). No adjustment Is provided and
a visual inspection is usually all that is requi red. if
this setting is not correct, look for insufftcieat
travel of the trip shaft (7).
Trip Armature Travel

Fig. 12 (8037374) Primary Contact Adjustment
1.

Contact Spring

2.
3.

Buffer Retainer
Buffer Block

4.
5.

Stationary Primary Contact
Movable Arcing Contact

7.
8.
9.
0.

Arcing Contact Bmts
Primary Contact Bolts
Cupped Hinge Washer
Hinge Nut
Operating Rod

2.
3.

Movable PrimaryContact

Adjusting Nut
Check Nut

4. Operating Rod Stud

Refer to Figure 8.
The trip armature
should have 7/32" to 9/32" travel before the »r^p
latch (8) starts to move. This can be adjusted
moving the trip coil support (2) and/or by id|uetu^
the trip armature screw (14), Figure 9. A U>-aii«
screw located behind the trip armature screw mwet
first be loosened. Retighten locking screw anet
making adjustment.
Release Latch Wipe

Refer to Figure 4. The wipe between the reteeee
latch (14) and roller (8) should be 3/16" to i e
If re-setting is required, loosen, set, aoe f*tighten adjustment nut and screw (5).

G£;i»S8774 Magn»'Blast Circuit Breaker
advance the ratchet wheel (7) sufficiently on each

Release Latch Monitoring Switch

stroke

Refer to Figure 4. The release latch must be
' 'uUy re-set and the latch monitoring switch (20)
operated before the motor will start. When the latch

is fully reset the clearance between the switch
striker arm and the switch mounting bracket (21)

is 1/32" or less, this can be ad^sted by bending
the striker arm.

to allow the latching pawls (3) to fall

into the ratchet teeth. This should be checked~with

check the maximum clearance between the pawl
Motor and Relay Switches

and the ratchet tooth. Rotate the charging wrench
until the driving pawl has advanced the ratchet tooth

Refer to Figure 4. With the closing springs
blocked rotate the switch cam (9) until the switch
striker (10) has traveled the maximum amount
(about 160 degrees rotation of cam). At this point

to its maximum travel.

the clearance between the striker and the switch

suiqwrt (12) should be 1/32" or less. This can be
adjusted by loosening the switch support mounting
bolts (15) and rotating the support.

Now check the clearance

between the ratchet tooth and the latching pawl. The

clearance should be approximately equ^ for both
the driving and latching pawls and not less than
.015" in ei&er case.
If adjustment is required for either pawl the
springs must first be fully charged and blocked.

Loosen seven motor support bolts (2) Figure 7
Interlock Switch Wipe

and move entire motor assemblyup if the clearance
is under the minimum at the latching pawls,

Refer to Figure 13. With the positive interlock
in the reset, or normal position the clearance
between the interlock switch arm (4) and the switch
mounting plate should be 1/32" or less. This
can be adjusted
bending the switch arm.
Driving Pawl Adjustment
Refer to Figure 5.

The driving pawl must

and down if the clearance is under the minimum

at the driving pawl. Move the motor assembly
approximately twice the dimensional increase re

quired at the pawl. Be certain the motor assembly
is moved straight up or down and tighten the one
bolt on the left of the mounting frame first to
assure proper alignment. After tightening the re
maining bolts the springs should be released and
the clearance again checked as described above.

Fig. 13 (8037375) Interlock Switches
Manual Trip Lever
Interlock Shaft

6.
7.

Auxiliary Switch
Switch Support

Secondary Coupler

Latch Check Switch

Interlock Switch Arm

Switch Arm -

Interlock Switch

10. .Trip Shaft

Uagne Blast Circuit Breaker GEI-88771

AUXILIARY DEVICES
b.

Primary contact wipe: 1/4" to 5/16",
Arcing contact wipe: 5/16" or greater

giq;> at primary contacts.
Primary contact gap: 3-5/8" to

atch Checking Switch

Refer to Figure 14. Charge the closing springs
sufficiently to reset the mechanism linkage. Rotate

the trip latch (4) by pressing the manual trip lever
to open the latch checking switch (2). Allow the
trip latch to reset slowly and determine the point
at which the contacts are made by using a circuit
continuity tester (light indicator, bell set, etc).
The contacts of the latch checking switch should
ust make when the gap between the trip latch

3-15/16".
Trip latch wipe: 3/16" to 1/4" with trip
latch resting against stop pin.

Trip armature travel 7/32" to 9/32".

f.
e*

Release latch wipe: 3/16" to 1/4".

(7) is 1/1o". There should be a minimum of
764" between the switch arm (3) and the switch
support (1). To obtain adjustment of the latch check
ing switch, bend the latch checking switch arm (3).

Interlock switch: maximum clearance

Driving and Latching Pawl: minimum

1/32".
clearance to ratchet teeth .015".
k.

and the stop pin is 1/16".
Auxiliary switch operator - 14-3/8"
to 14- 7/16".

Check all nuts, washers, bolts, cotter pins,

Inject all wiring to make sure that no

dai^e has resulted during installation, and

Inspection and Test

Latch checking switch contacts make
when the gap between the trip latch

and terminal connection for ti^tness.

is set and pinned at the factory and no adjust
ment is provided.

maximum

Auxiliary Switch Operator

line should be 14-3/8" to 14-7/16". This adjustment

Motor and relay switch:

clearance 1/32".

14) and the stop pin (5; located on the latch roller

Refer to Figure 6. With the breaker in the
closed position, the vertical distance "A" from the
top of the roller on the crank (3) to the floor

Release latch monitoring switch: Max
imum clearance 1/32".

test for possible grounds or short circuits.

For ease in reviewing the adjustments, the
following are recapitulated:

See that all bearing surfaces of the mech
anism have been lubricated.

section on LUBRICATION.

Figure 16).

Refer to the

(Page 18 and

Operate the breaker slowly with the manual
charging wrench and note that there is no
excessive binding or friction and that the
breaker can be moved to the fully opened and
fully closed positions.

See that any place where the surface of the
paint has been damaged is repainted immed
iately.

Check the trip coil plunger and the rele
coil plunger to see that they move freetv

Opening and Closing Speeds

Q
8

Figure 14 (0121caiS2) Latch Checking Switch
1. Switch Support
5. Reset Pin Stop

2. Latch Checking Switch 6. Latch Roller
3. Switch Arm

7. Latch Roller Link

4. Trip Latch

8. Latch Roller Pin

The closing speed of the arcing contact of tne
breaker should be a minimum of 11 feetper second.
This represents the average meed of the morabte
arcing contact from a point 3" before the tip le
tangent to tiie lower surface of the probes on me
rear arc runner to the tangent position.
The opening speed of the arcing contact ennus
be a minimum of 12 feet per second. This r«pre>
sents the average speed over 3" from the poue
when the tip on the movable arcing contact .•
tangent to the lower surface of the probes on me
rear runner. Proper servicing and lubncstioa
of the breaker and its operating mechanism
maintain these speeds and no adjustment is prcm^s

]

Magne Blast Circuit Breaker
♦

.oatrol Power Check

After the breaker has been operated several
times with the manual charging wrench and the

mechanism adjustments are checked as described,

the operating voltages should be checked at the
release coil, trip coil, and motor terminals.
Control Power for electrical operation of the
breaker may be from either an alternating or
direct current source. The operating ranges for
the closing and tripping voltages as given on the
breaker nameplate, are as follows:
Hoolnal

Voltage
a^lv
t|6v

d-c
d-c

Trippiixg
Range

Closing
Range

3OV

d-c

5OV
115v

d-c

60v

d-c

- 125v
- l40v

d-c

UOv

d-c

311 80 -

125v

dfC

130v

220v

d-c

160

230v

70
d-c
d-c 120

250v
U^v
230v

d-c
a-c
a-c

180

260v

d-c

95
190

125v
25OV

8-C

a-c

140
95
190

If the closed circuit voltage at the terminals

of the coil or motor does not fall in the specified
range, check the voltage at the source ofpower and
line drop between the power source and breaker.

When two or more breakers operating from the
same control power source are required to close
simtiltaneously, the closed circuit voltage at the
closing coil or motor of each breaker must fall
within the specified limits.
Electrical closing or opening is accomplished by
energizing the closing or trip coil circuit. Control
switches are provided for this puzpose on the
metal-clad unit. It is also possible to trip or close
the breaker manually by pressing die manual trip
lever (1) Figure 2 or the manual close button (6).

d-c

25OV

d-c

- 28OV
- 125V
- 25OV

d-c
ae>C
a^c

GENERAL MAINTENANCE
General

Safe and dependable service from electrical ap
paratus and power systems is contingent upon re

liable performance (rf power circuit breakers. To
obtain maximum reliability the breaker should be
inspected and maintained on a regular schedule.
The breakers are designed in accordance with ap
plicable standards which require that they be
capable of performing up to 5000 operations for
1200 ampere breakers and 3000 operations for 2000
anqiere breakers switching rated continuous cur
rent before any replacement of parts should be
necessary.
This requirement is based on the
breakers being serviced, or maintained, at least
every 2000 operations, or once per year, whichever
comes first. If the breaker is also required to
interrupt fault currents during this period of time

additional maintenance and r^lacement of parts
may be necessary.
BEFORE ANY MAINTENANCE WORK IS PER

FORMED, MAKE CERTAIN THAT ALL CONTROL
CIRCUITS ARE DE-ENERGIZED AND THAT THE

BREAKER IS REMOVED FROM THE METAL-CLAD
UNIT.
DO NOT WORK ON THE BREAKER OR
MECHANISM WHILE IN THE CLOSED POSITION

UNLESS THE PRQP AND TRIP LATCH HAVE
BEEN SECURELY WIRED OR BLOCKED TO PRE
VENT ACCIDENTAL TRIPPING. DO NOT WORK
ON THE BREAKER OR MECHANISM WHILE THE
SPRINGS ARE CHARGED UNLESS THEY ARE
SECURED IN THAT POSITION BY THE MAIN

TENANCE SPRING BLOCKING DEVICE.
Periodic Inspection

The frequency of the inspection and maintenance
operations required should be determined by each
16

operating company and will depend on the application
of the breakers and the operating conditions.
Factors which should be considered are: Inqmrtance
of the breakers to overall plantor system operation;
number of operations and magnitude of currents
switched by breaker; frequency of fault inter
ruptions; and the atmospheric conditions in wtuch
the breaker normally operates. Extreme cmidltlons
of dust, moisture, corrosive gases etc., can indicate
that inspection and maintenance will be required
more frequently than every 2000 operations. Very
clean dry operating conditions with low current
switching duty can justify a longer period of time
between inspections. Any time a breaker is known
to have interrupted a fault at or near its rating it is
recommended that the breaker be inspected and
necessary maintenance be performed as soon after

the interruption as is practical. The foUowtng
instructions give the items that should be uaciuded
in an inspection and general recommendatloos on ui«
maintenance of breakers.

Interrupters

Since there arenomovingparts, the interrupters
of a magneblast breaker will normally require
little or no inspection unless there is aeid—i e
of damage to the arc chutes sides orcontaausstioa
in the throat area. If eitherof these conditmas are

present the interrupters should be removed fmei
breaker and the following points noted:

The throat area of the internqrter atmuu
be cleaned with san(h>aper (Do
emery cloth or other metallic ab.
All flat areas on either side of the auwstu*

arcing

contact travel should be

Do not sand or otherwise attempt tn

t'l

Magne Blast Circuit Breaker
the ceramic fins of the arc chute sides.

Heavily contaminated parts should be re
placed.
Cracks which have formed in the fins of the

arc chute are to be expected in ceramic
materials of this type when subjected to
the severe heat of an arc.

These cracks

do not interfere with the operation of the
device in any way and should be disregarded.

GEI-88771

be repaired or the part replaced.
Interrupter Removal i^nd Replacement

To remove an interrupter, open the breaker
contacts and remove the top cover and box barrier.

Referring to Figure 15, loosen the two rear support
bolts (6) and the one front support bolt (3) using
a standard 3/4" wrench.
Slide the complete
interrupter assembly approximately 3/9" toward

the rear and remove by lifting straight up.

If the arc chute has suffered any mechanical
injury due to dropping or accidental striking,
resulting in the actual breaking off of fins,
replacement will be necessary. Small

To reassemble the interrupter to the breaker,
lower the interrupter into the front support (2) and
over the rear support (7). Slide the interrupter

broken corners on the exhaust end of the
arc chute sides will not interfere witt its

assembly toward the front making certain that the
cut-out in the interrupter support engages the bolt

performance and can be disregarded.
The plastisol flexible covering for the pole
interrupter support (10) ahould be inspected
for breaks in &e insulation. If there are
holes or breaks in the insulation they should

(6). On the "-ID" design check to assure that the
throat insulation (7), Figure 18 in the interrupter
is properly positioned within the throat barrier
extending from

the

stationary

contact support

(5), Figure 21.
Tighten the supporting bolts (3) and (6), Figure

Interrupter

Front Interrupter Support
Front Support Bolts
Booster Cylinder
Rear Vertical Barriers

Rear Support Bolt
Rear Interrupter Support
Movable Arcing Contact
Stationary Arcing Contact

Primary Finger
Movable Primary Contact
Contact Arm
Front Vertical Barriers

Fig. 15 (8037385) Interrupters partially removed showing accessibility of Arcing Contacts

GEI-3fi771 Magne Blast Circuit Breaker

15. These bolts serve as both the electrical and
^ mechanical connections between the bushings and
ihe arc runners within the interrupter. Check
^/^^hat the movable arcing contact (8) passes between
e probes on the rear arc runner (5) Figure
x8 without touching.

may have been affected by moisture absorption.
If the breaker secondary wiring is to be given
a high potential test at 1500 volts, remove both of
the motor leads from the terminal board. Failure

to disconnect the motor from the circuit may cause
damage to the winding insulation.

Breaker Contacts

Bv removing the top cover and the box barrier

the movable and stationary primary contacts and

Lubrication

the movable arcing contacts can be inspected. The
stationary arcing contacts can be inspected only

In order to maintain reliable operation, it is
important that all circuit breakers be properly
lubricated at all times. Most of the bearings and

or bitted, they can be made smooth with

that will require no maintenance and will last the

after removing the interrupter. If the contacts are
a fme file.

After completing inspection of the contacts,

check the contact adjustments as specified under
ADJUSTMENTS,
Mechanism

A careful inspection should be made to check

rolling surfaces utilize a newtype of dry lubrication

life of the equipment. Only few bearings and sur
faces listed in the chart, Figure 16, require
lubrication. These have been properly lubricated
during assembly at the factory, using the finest
grades of lubricants available. However, even the
finest oils and greases have a tendency to oxidize
with age, as evidence by hardening and darkening
in color.

Elimination of the hardened lubricant

for loose nuts or bolts and broken retaining rings.

is essential for the proper operation of circuit
breakers. Also frequent operation of the breaker

wear. Lubricate the mechanism as outlined below,
then, using the manual charging wrench, open and

the bearing surfaces. A simple lubrication will

All cam, roller, and latch surfaces should be
inspected for any evidence of damage or excessive

causes the lubricant to be forced out from between

often clear up minor disturbances which might

close the breaker several times to make certain

be mistaken for more serious trouble.

as specified under ADJUSTMENTS.

up taking into consideration the frequency of opera

that the mechanism operates freely throughout its
entire stroke. Check the mechanism adjustments
Check the

^ontrol wiring for tightness of connections and

^^amaged insulation.

jshings and Insulation

The surface of the bushings should be kept clean
and unmarred to prevent moisture absorption.

H the insulation surface should become damaged,

it should be sanded and cleaned, and should be
refinished with either clear varnish or clear
resin. Allow to dry smooth and hard.

All other insulation parts on the breaker should

be kept clean and dry. Smoke or dust collected

A definite lubrication schedule should be set

tion of the breaker and local conditions.
It is recommended that lubrication of the breaker

and its operating mechanism be a part of the per
iodic inspection and maintenance program, withnot
more than a two year period between lubrications.
It is also recommended that all circuit breakers

be operated at regular intervals, at least once
a year, to insure the lubrication is in good
condition and the breaker is operable.

The lubrication chart. Figure 16,is divided into

two methods of lubrication. The first method out
lines the maintenance lubrication which should rw

between inspection periods should be wiped off,

performed at the time of periodic maintenance, end

dryness.

lines a lubrication procedure similar to that per.
formed on the breaker at the factory, andshould tw

Md if dampness is apparent, heaters should be
installed in the metal clad switchgear to insure

requires no disassembly. The second method out

used when a general overhaul of the breaker .«
• Insulation Test

When insulation has been repaired or replaced,

or when breaker has been operating in adverse
moisture conditions, it is recommended that the

msulation be checked before the breaker is placed

back in service. A standard 60hertz high potential
14,000 volts RMS for one minute will nor

mally indicate whether th&breaker is satisfactory
for service. With the bre&er contacts in the fully

opened position, apply the test potential to each
«rminal of the breaker individually with all other

^^ndMls and the breaker frame grounded. After
'h potential tests are made on organic insulating
,tertals, these materials should be inspected for
visible leakage current paths, andnecessary action
must be taken to repair or replace insulation that

necessary.

General Electric Lubricants D50H1S and DMHe^

are available in 1/4 lb. collapsible tubes,

rt .•

so packaged to insure cleanliness and to prreeM
oxidation.

METHOD OF CLEANING
BEARINGS

Whenever cleaning of bearings is required. ^
indicated in the lubrication chart, the foU*7wv«
procedures are recommended:
Sleeve Bearings

The sleeve bearings used throughout,.the

Magne Blast Circuit Breaker GEI-&d771

1
PART

Sleeve Bearings - links,

trip shaft, etc. (Teflon
coated bearings)

ALTERNATE LUBRICATION

No lubrication

No lubrication required.

Light application of machine
o i l SSE 20 or

SAE 30.

Contact Arm Hinge AssemblyCup bearing
Loose rings between bushing

(REQUIRES DISASSEMBLY)

required.

Sleeve Bearings - main crank
shaft, driving pawl lever.

(Bronze or cast iron)

LUBRICATION AT
MAINTENANCE
PERIOD

No lubrication

required.

Remove bearings or links
clean per instructions
and apply D50H15 lubri
cant liberally.

Wipe clean and apply
D50H47.

and contact arm.

Roller and Needle Bearings

Light applica
tion of machine
o i l SAE 20 or

Clean per instructions
and repack with D3OHI3
lubricant.

SAE 30.

Oround surfaces such as

cams, ratchet teeth, etc.

No lubrication

No lubrication required.

required.

(Surfaces coated with K0S2)
Oround surfaces such as

latches, rollers, prop,
etc.

Silver plated contacts and

primary disconnect studs.

Wipe clean and
apply D5OHI5

Wipe clean and apply
D5OHI5 lubricant.

lubricant.

Wipe clean and

apply D50H47.

[

Wipe clean and apply

D50H47.

Booster Cylinder

Do not
Lubricate.

Do not lubricate.

Arcing Contacts ^

Do not
Lubricate.

Do not lubricate.

Figure 16 Lubrication Chart

GEI-8tf771 Magne Blast Circuit Breaker

utilize Teflon surfaces and do not require lub' Icatlon.

After a number of operations, the sur-

^ce will acc^re a thin black film. Do not remove
^d^his film umess there is evidence of outside con^Tilnates, such as dry or hardened grease. If

factorily with petroleum solvent or a similar
cleaner and a stiff bioish. Follow the procedure
outlined above using a light machine oil and G-E
lubricant D50H15 before reassembling the inner
race and shaft.

.ontaminants are nresent thev should be removed

by immersing the link and bearing in clean petro
leum solvent, or similar cleaner, and using a
stiff brush. Do not remove the bearings from the

Rolling Surfaces

links.

mechanism have been lubricated with a baked-on

DO NOT USE CARBON TETRACHLORIDE.

The hinge of the primary contact arm (22)
Figure 21, should be disassembled, cleaned, and
lubricated with G-E D50H47 lubricant at general
overhaul periods.

The main shaft bearings (24) Fimre 8 and the
bearings in driving pawl lever (6) Figure 7,
should be removed, cleaned, and lubricated with
G-E D50H15 lubricant at general overhaul periods.

A number of rolling and rubbing surfaces in the
dry, molybdenum disulfide coating. This lubrication,
which can be recognized by its dark, almost black

color (e.g. Face of switch cam (9) Figure 4) re
quires no maintenance and should last the life of
the breaker.

Other rolling or rubbing surfaces that are not
lubricated with molybdenum disulfide should have
the dried, dirty grease removed and a thin film

of fresh lubricant D50H15 applied.
MAINTENANCE

Roller and Needle Bearings

Refer to Figure 8. The cam follower bearings
(6), latch roller bearing (9), and cam shaft bearings

Magne-Blast breakers used for switching arc
furnaces or capacitors will require more frequent

(25) should be removed from the mechanism and
the inner race disassembled. They should then be
placed in a container of clean petroleum solvent

because of the repetitive nature of the applications.
The following schedule is recommended for such

breakers;

similar

cleaner.

NOT USE

CARBON

TETROCHLORIDE. If the grease in the bearings
has become badly oxidized, it may be necessary to
use alcohol (type used for thinning shellac) to
emove it. Ordinarily, by agitating the bearings in
ae cleaning solution, and using a stiff brush to

and more defiled inspection and maintenance

Every 500 Operations, or Every Six MonthsWhichever Comes First:

Remove the top cover and box barrier.

bearings are inductive to corrosion. If the bear

Wipe all insulating parts clean of s moke
deposit and dust with a clean dry cloth,
including the bushings, and the inside

ings are touched, the contamination can be removed

of the box barrier.

/«^move the solid particles, the bearings can be
' ^tisfactorily cleaned. Do not handle the bearings
with bare hands as deposits from the skin onto the

by washing in ^cohol. After the bearings have
been thoroughly cleaned, spin them in clean new
light

machine

oil until the cleaner or solvent

is entirely removed. Allow this oil to drain off and
then repack them immediately with G-E lubricant
D50H1S being sure all metal parts are greased.
The inner races should then be assembled.

All flat parts in the throat area of the
interrupters should be thoroughly clean
ed by using sandp^er. This cleaning
should be performed any time the inter
rupter is removed. The fins on the
arc chute sides should not be cleaned.

Whenever the interrupter is removed,

NOTE: If it becomes necessary to clean the
bearings in alcohol (shellac thinner), be sure

the alcohol is perfectly clean, and dp not allow the
bearings to remain in the alcohol niore than a few
hours. If it is desirable to leave the bearings in
the alcohol for a longer time, an inhibited alcohol

loose dust and dirt should be blown

out before replacing arc chutes. Throat
insulation which is heavily contaminated
should be replaced.

Every 2000 Operations, or Every Six Months

such as is used for anti-freeze should be used.

Whichever Comes First:

Even then the bearings should be removed from the
alcohol within twenty-four hours. Precautions

against the toxic effects of the alcohol must be

exercised by wearing rubber gloves and by using
the alcohol in a well ventilated room; excessive
exposure to the fumes is sometimes unpleasant

to personnel. Washing tAe bearings in the light
oil, draining and repacking with lubricant D50H15
"hould follow immediately.
Bearings that are pressed into the frame or other

:mbers such as the motor support (4) Figure 7,
.lould not be removed. After removing the shaft
and inner race the bearing can be cleaned satis
20

In addition to the servicing done each
500 operations, the following inspection
should be made and work done when
required.

Primary Contacts (19 and20 Figure 21
Inspect the condition of the stationarv

contact fingers and movable conuct
blocks. Badly pitted or burned contacts
should be replaced. (Note: Burned
primary contacts indicate the protiabie
need for arcing contact replacement.
If the contact surfaces are only rough-

t *

Magne Blast Circuit Breaker GEI-887'il

tion of insulation, blow-out coils, arc

ened or galled, they should be smoothed

-witii crocus cloth or draw filed. After

runners

contact dressing the primary contacts
should be greased lightly with DS0H47.

Ijecome contaminated by arc products.
2.

than the minimum specified under AD

action and heat so that the turns of the

JUSTMENTS, the contacts shmild be
replaced.
The contacts should be

other, the coils should be replaced. All

age using a mirror to inject the

tightness.

stationary contacts.

examined and if the insulation has been

coils are not fully insulated from each
connections

tact condition indicate a need for re

arc erosion.

Do not grease the arcing contacts xmder

Check the breaker and mechanism ad

Insxilating material that is carbonized
and cannot be satisfactorily cleaned
should be replaced.

Any parts damaged or severely turned
and/or eroded from arc action should

justments as sununarized under IN
SPECTION AND TEST. The necessary
readjusments should be made as de
scribed under ADJUSTMENTS.

The breaker and operating mechanism
should be carefully injected for loose
nuts, bolts, retaining rings, etc., all
cam, latch and roller surfaces should
be inspected for damage or excessive

be replaced.

NOTE: Fine cracks may develop on the
fins of the arc chute sides. This is to

be expected with ceramic materials

when subjected to the high heat of an
arc and may be disregarded unless
they are long and present a possibility
of fin sections breaking completely off.

. The buffer blocks and their

retainers on the bottom of the stationary
contact support should be inspectedfor
possible need of replacement.

Check the stationary arc contacts to
assure that the arcing contacts are in
good condition and that their connections
are tight.

any circumstances"

The arc runners should be inspected
and replaced when any part of their
area has been reduced to 25% of the
original metal thickness as a result of

placement. If the interrupters are re
moved, the contact braids, and other
parts subject to arcing should be check
ed for possible cleaning or replacement.

wear.

should be checked for

Normally it will

rupters for this 2000 (deration ser
vicing unless inadequate wipe or con

The blow-out coils should be carefully
cracked, shrunk or eroded from arc

not be necessary to remove the inter

assemblies which can

Arcing Contacts (2 and 7 Fiaure 21).
When the arcing contact wipe is less

inspected for uneven wear and/or dam

smd

Small broken comers on the exhaust
end of the arc chute will not interfere

The contacts of the control relay (12)
Figure 3, should be inspected for wear
and cleaned if necessary.

with its performance and can also
be disregarded.

Lubricate the breaker operating mech

anism in accordance with instructions

The cup bearing (23) Figure 21 and the
contact ring at the hinge point of the

contact blade should be Reassembled,

under LUBBICATION, page 18 and the
lubrication chart Figure 16.

inspected,

cleaned, and relubricated

with G-E contact lubricant DS0H47.

Inspect all wiring for tightness of con
nections and possible damage of in

The contact ring should be inspected
for wear and replaced when reduced

sulation.

in thickness to less than 1/32". When
reassembling the cup bearing, be sure
the cotter pin is properly assemtiled
in the castle nut on the hinge pin

After the breaker has been serviced,
it should be operated manually to be
sure there is no binding or friction

(24).

to the fully opened and fully closed
positions.
Its electrical operation
should then be checked using either

This assures proper conurt

pressure at the hinge.

and that the breaker contacts can move

Every 20,000 Operations or Approximatelv
Every Five Years - Whichever comes ft r»t

the test positi)8n or the test couplers.

1.
C.

After Every 10.000 Operations;

1. In addition to the ser^cing done each

The breaker should be given a general
inspection and overhaul as required.
All excessively worn parts in both the
mechanism and breaker should be re

2000 operations, the interrupters should

placed.

be removed from the breaker and dis

indicated when the breaker cannot t>e

assembled to permit a detailed inspec

adjusted to indicated tolerances. This

Such wear will usually t>e

Q]E!I-88771 Magne Blast Circuit Breaker
overhaul and inspection is more detail
ed and will require disassembly of mech
anism and breaker operating parts.
2.

All roller and needle bearings in the
operating mechanism should be dis
assembled, cleaned, and repacked with

In general, repair work can be accomplished
with the removal of the top cover and box barrier

only.
However, when it is necessary to remove
the side covers and front cover, they should be
removed as an integral unit. Whenre-assembling,
the dowel pins will reposition the covers to assure

satisfactory alignement within the metal-clad unit.

G. E. lubricant D50H15 as described
under LUBRICATION.

ARC CHUTE (to inspect or replace blow-out colls
and arc runners);

The stationary primary contactfingers
(19) Figure 21, should be disassembled
and the silver-plated pivot area of the

contact and contact support cleaned and

and the box barrier (7), Figure 10. The interrupter

lubricated with G-E. lubricant D50H47.

With the breaker open and the closing springs
the blocked position, remove the top cover

can now be removed as described under REMOVAL

AND REPLACEMENT page 17,

The breaker and operating mechanism
should be

serviced

as described for

every 2,000 operations and properly
adjusted before being put back into

To disassemble the interrupter after ithasbeen
removed from the breaker, proceed as follows;
NOTE;

service.

When disassembling the arc chute and

its components some small washers, spacers, etc.,
REPAIR AND REPLACEMENT

This section covers the proper method of
removing and replacing those parts of the breaker
subject to damage and wear that may require repair

will be found that cannot be identified in these
instructions.
Care should be taken to collect

and identify these items so they canbe reassembled
correctly.

or replacement at the installation. IMPORTANT:

UPON COMPLETION OF ANY REPAIR WORK. ALL
BREAKER AND MECHANISM ADJUSTMENTS MUST
BE CHECKED. Refer to thesectiononlNSTALLA-

Remove the caps and assembly bolts (7,
9, 11, & 13), Figure 17.

Remove the side brace (5), and poie pieces
(3 & 6).

TION, payingparticular attention to ADJUSTMENTS
and FINAL INSPECTION.

Assembly Bolts and Bushing
Assembly Bolts
Rear Pole Piece

Assembly Bolt
Side Brace
Front Pole Piece

Assembly Bolt
Front Brace

Assembly Bolt
Rsar Interrupter Support
Insulating Cap
Side Shield

Assembly Bolt
Front Interrupter Support

Assembly Bolts
Assembly Bolts

Fig. 17 (8039601) Interrupter Assembly

Magne Blast Circuit Breaker GEI-88771-

Rear Arc Runner Spacer
Rear Arc Runner Assembly
Blowout Core
Blowout Coil

Rear Arc Runner
Arc Chute Side

Throat Insulation

Front Runner Shield
Front Arc Runner

Blowout Coil

Blowout Core

Front Insulation

Front Arc Runner Assembly
Front Coil Connection

Front Arc Runner Spacers

Fig. 18 (8039603) Interrupter Assembly with Side Removed

Rear Mounting Support
Connection Bolt
Insulation Plate

Rear Arc Runner Assembiv

Side Shield

Front Arc Runner Assembly
Front Coil Connection

Connection Nut

Front Mounting Support

Fig. 19 (8039604) Interrupter Assembly

,r>EI»68771 Magne Blast Circuit Breaker
arc chute sides measured at least T'lnfrom
the back end of .the arc chute (See Figure
20) should be 1/64" to 3/32".

Check to insure that electrical connections
to the blowout coils are tight.

When reassembling the arc runner as
semblies, check that the spacers are cor
rectly installed.

Before bolting the rear supports in place,
make

certain

that the rear arc runner

assembly is tight against the arc chute
side so that the gap between the throat

insulation (7), F^re 18, and the arc

chute sides (6) is a minimum.

Make certain that the electrical connections
(2 & 8), Figure 19 are tight.

Reassemble the arc chute on the breaker as
described under INTERRUPTER REMOVAL AND

REPLACEMENT, page 17.
CONTACTS

Fig. 20 (8029373) Arc Chute Fin Spacing

Open the breaker and remove the top cover,

box barrier, and interrupters as previously de
3.

To remove the rear interrupter support
(10) remove the assembly bolt (1), and
the bolted connection (2) Figure 19 between
the rear interrupter support and the blow-

scribed.

out coil.

Stationary Arcing Contacts (2), Figure 21.
1.

Disconnect the contact braids (4) from
the contact fingers by removing two
bolts and locking plates (14).

Grasp the front end of the contact
fingers with pliers and pull contact
assembly forward to remove from stud
assembly.

Remove the assembly bolt (16), Figure 17
to remove the front brace (8).

Remove the front interrupter support (14)
by removing the assembly bolts (15) and
the connection nut (8), Figure 19.

At this point, the side shields (12), Figure
17, and the arc runner assemblies (4 & 6),

Further disassembly of both the rear and
front arc runner assemblies can be done by
removing the various screws and assembly
bolts (not illustrated) as shown in Figure

The arc chute sides (6) Figure 18, can
also be separated for inspection after

disassemble

braids

from stud

To disassemble stud platefromcontact
support, remove two bolts (3).

18*

plate remove one bolt (13).

Figure 19 can be removed.

To remove the contacts, proceed as

follows:

Reassemble in the reverse order, make
sure locking plates are properly re
assembled with bolts (14).

Movable Arcing Contact (7) Figure 21.

removing assembly bolts (2 & 4), Figure
17.

Reassemble the internipter In the reverse order.
The following items should be noted during re
assembly:
^

contact arms.

2.
1.

The fins of the arc chute sides should be

equally spaced and aligned before bolting
together. The front edge (along the runner)

of the two arc chute sides shouldbeparallel
2.

Remove the assembly bolts (8) raaklsg
note of quantity and location of shims
and spacers used between contacts aad

Reassemble in reverse order, re-uauig
the shims and spacers.

Close the breaker slowly to chee
reinstalled in the same location.

However, it is possible to remove and re
assemble three bushings at one time. If this is
preferred, alignment of the bushings may
accomplished by placing the breaker in a
energized spare metal-clad unit before tigtits• >.> m: .Mngne Blast Circuit Breaker
•v

"n.
^

Replace the coil and the correct number
oX fiber spacers before bolting support.
and

check that the

armature is not binding.
electrical iteration.

Butt

connect wires

Check coil for

4.
5.

the opening springs with a suitable blocking
device.

The closing springs (10) Figure 3, can be
removed as foUows:

blocking pins (13) supplied in the tool

proceed as foUows:

Rotate cam shaft (6) Figure 5, by using
the manual charging wrench until the gap
between the spring (11) and the bearing
block (8) is a maximum (approximately
3").

Push manual trip lever (1) Figure 2, to

♦)

be sure the opening springs are fully

Discharge springs by pushing manual close

discharged.

button (o) Figure 2.
3.

Charge and block the closing springs as
described under INSTALLATION.

msert pin so that it is centered

in the spring support.
2.

OPENING SPRINGS

To remove the opening springs (5) Figure 5,

Charge the springs with the manual charg
ing wrench and apply the special short
kit.

Either discharge the opening springs-by
pushing the manual trip lever or block

CLOSING SPRINGS

Remove cotter pin and washer from spring

guide pin and remove closing spring (U)
and upper spring guide (8) as a unit.

Remove rear pin (2) Figure 5, and front
pin (9).

After reassembling springs check the open
gap at the primary contacts as described
under PRIMARY CONTACT GAP.

RENEWAL PARTS
It is recommended that sufficient renewal parts
; carried in stock to enable the prompt replace-

^e^nt of any worn, broken, or damaged parts. A
I

>:k of such parts minimize service interruptions
...used by breakdowns, and saves time and expense.
When continuous operation is a primary consider
ation, more renewal parts should be carried, the
amount depending upon the severity of the service
and the time required to secure replacements.

Renewal parts which are furnished may not be
identical to the original parts since improvements
are made from time to time. The parts which are
furnished, however, will be interchangeable.
NOTE:
The listed terms "Right" and "Left"
apply when facing the front or panel end of the

ORDERING INSTRUCTIONS

Always specify the complete nameplate data

♦)

of both the breaker and the mechanism.

Specify the quantity, catalog number (if
listed), reference number (if listed), and
description of each part ordered, and this
bulletin number.

Standard hardware, such as screws, bolts,
nuts,

washers,

etc., are not listed and

shomd purchased locally.

For prices, refer to the nearest office of
the General Electric Company.

breaker.

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In the following tabulations are listed those parts of the breaker and
operating mechanism which are usually recommended for stock for
normal maintenance. Other parts can be obtained by contacting the
nearest office of the General Electric Company.

Magne Blast Circuit Breaker GEI-88771
RECOMMENDED RENEWAL PARTS FOR

TYPE ML-13A STORED ENERGY MECHANISM

USED FOR AMH-4.76-250-0D & ID, 1200 & 2000 AMPERE
Fig.
No.

Ref.
No.

•

No.

Description

Req'd.

Spring Charging Motor - *♦

Catalog No.

|
t

48 V-DC

i 0105C9393P001

110 & 125 V-DC & 115 V-AC, 60 Hz . 0105C9393P002

220 &250 V-DC &230 V-AC, 60 Hz j 0105C9393P003
12 1 1

!
!

j Relay - ♦*, #
!

48 V-DC

110 & 125 V-DC
220 & 250 V-DC
115 V-AC, 60 Hz
230 V-AC, 60 Hz

Potential Trip Coil - **
110 & 125 V-DC
220 V-DC
250 V-DC

115 V-AC, 60 Hz
230 V-AC, 60 Hz
24 V-DC
48 V-DC

115 V-AC, 60 Hz
230 V-AC, 60 Hz
48 V-DC

4
4
9
4
9

13
13
4
18
7

*
**

5
1
1
1

1
1
2

006174582G001
006174582G015
006174582G002
006174582G013
00 6174582G032
006275070G001
006:74382G034

Spring Release Coil - **
110 & 125 V-DC
220 V-DC
250 V-DC

0137A7575P004
0137A7575P001
0108B1978G001
0137A7575P005
0137A7575P002

Switch, Normally Open
Switch, Normally Closed
Auxiliary Switch

Closing Latch Spring
Prop Spring

Driving Pawl Spring
Latching Pawl Spring

006174582G001
006174582G015
006174582G002
006174582G010
006174582G014
006174582G034

0456A0866P005
0456A0866P006
0161A4231P001

0137A9252P001
0161A4241P001
0161A5909P001

Not Illustrated

Refer to breaker nameplate or summary for proper voltage rating.

Quantity Two (2) relays required on special control circuits. Check
breaker and connection diagram.

Refer to breaker auxiliary switch for proper model
Type SBM - 0137A9192G003
Type SB-12 - 0137A9192G011
* Indicates Revision

GEX*fi8771 Magne. Blast Circuit Breaker

RECOMMENDED RENEWAL PARTS FOR MAGNEBLAST BREAKERS

•)'

TYPE AMH-4.76-250-0D Si -ID, 1200 Si 2000 AMPERES

Fig. Ref Ampere
No.

No. Rating

10
10
10
10
21
21
21

13
21

21
21

21
21
21
17
17
18
18
18
18
19
*

-OD

0195A4091GG01
0195A4091G002

ALL

0137B7g02G001. 0137B7902G001
0213X0343G043 0213X0343G090
0213X0343G044 0213X0343G091
0236C0790G009 0236C0790G009
0236C0791G001 0236C0791G001
0236C0791G004 0236C0791G004
0802B0742G001 0227A5306G004
0414A0116P004

1200
2000

2
4
4
7
16

ALL

ALL
ALL
ALL
ALL
ALL
ALL

ALL

11
11
7
7
8
12
3

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

0121A5964P001

0114C5382P002
0114C5382P004
000421711P001

00Q407193P001
0108B196SG001
0108B1965G002
0161A5906P001
0114C5381P001
0114C5381P004
0836C0197P014

* Not Illustrated

•ID

1200
2000

28
28

Catalog No. For Type AMH-4.76-250
0195A4091G001
0195A4091G002

0121A5964P001
0114C5382P002

0114C5382P004
00042171 IPOOl
000407193P001
0195A7377G00]
0195A7377G002
0161A5906P001
0114C5381P010
0414A0116P002
0836C0197P014
0195A7388G002

No.

Req"d,
6
6
3
3
3
3
3
3
3
3
18
18
6
6
6

3
3
6
6
3
6

Description

Primary Disconnect Fingers
Primary Disconnect Fingers
Operating Rod Assembly
Tube & Piston Assembly

Tube Si Piston Assembly

Arcing Contact Assembly
Flexible Connector (Left)
Flexible Connector (Right)
Movable Arcing Contact
Instilating Plate

Primary Contact Finger Spring
Primary Contact Finger
Movable Primary Contact
Insulating Cap
Threaded Washer (For Insul. Cipi

Throat Insulation (Left)
Throat Insulation (Right)

Front Runner Shield

Front Insulation

Insulating Plate

Rear Runner Insulation
Throat Barrier Assembly

4;.-

GENERAL ELECTRIC BREAKERS

TYPE AMH 4.76-250-0D, MAX. VOLTS 4760
MAX. AMPS 1200, 60 HZ MECH TPE ML-13A

Disassemble breaker. Inspect the movable and stationary primary contacts and
movable arcing contacts. All cam, roller and latch surfaces should be Inspected for
any evidence of damage or excessive wear. Check for loose nuts or bolts and broken
retaining rings.

Replace all teflon sleeve bearings with aluminlzed brass bearings (see G.E.
»

yfc.

specification).

Remove and inspect main shaft bearing, driving pawl bearing and all needle and

roller bearings. Remove and Inspect the cam follower bearings, latch roller bearings
and cam shaft bearings.

Remove arc chutes —meggar and ductor to determine If disassembly is
needed. Arc chutes contain blowout coils, arc runners and assemblies.

All lubrication of bearings and other wear surfaces shall be in accordance with
G.E. updated specifications.

All adjustments to the breakers shall be made to G.E. specifications or noted as
out of tolerance.

All renewable parts Installed shall be recommended G.E. replacement parts or
equivalent.

Breakers shall be hi pot tested using ANSI standards. Bushings shall be Doble

tested. The breaker operating mechanism shall be tested with atime motion analyzer a
for three phase contact closure.

' iy

B. Connell

.r>

G C'

CCiQ-CZg-v.T't c"T" •
jek:bc0418

OtC. -

/ L-C cS" c:'

/ 5 TC P

S j j j x - o o i I j-n.

INSTRUCTIONS AND

Supersedes GEI-88771
Ajr- 7/ -

RECOMMENDED PARTS
FOR MAINTENANCE

MEDIUM VOLTAGE SWITCHGEAR DEPARTMENT

GENERAL^ ELECTRIC
PHILADELPHIA. PA.

MAGNE-BLAST CIRCUIT BREAKER
-4.76-250-0D
AR/IH-4. 16-250-lD
INTRODUCTION
The magneblast breaker is the removable and
interchangeable interrupting elementused in metalclad switcl^ear to provide reliable control and pro

tection of electrical apparatus and power systems.

The AMH-4.76-250 Magneblast Breaker is avail
able with continuous current ratings of 1200 amperes

age, current, and interrupting ratings are never
exceeded.

Since this book is written to include

all ratings of the breaker as well as several design
variations, the instructions will be of a general
character and all illustrations will be typical unless
otherwise specified.

Refer to the breaker name-

PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SAT
ISFACTORY OPERATION OF THE BREAKER. The

ticular breaker. The nameplate also describes the

following instructions will provide complete infor
mation for placing magne-blast breakers in service

and 2000 amperes in accordance with applicable
industry standards.

plate for complete rating information of any par

control power reauirements for that breaker. The
application of a breaker must be such that its volt

and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
against condensation, preferably by storing

Receiving and Handling

it in a warm dry room, since water abso^tion has an adverse effect on the in

Each breaker is carefidly inspected and packed

for shipment.

sulation parts. Circuit breakers for out

Immediately upon receipt of the

circuit breaker, an examination should be made

door metal-clad switchgear should be stored

rough handling is evident, a damage claim should

able and the heaters are in operation to
prevent condensation.

in the equipment only when power is avail

for any damage sustained in transit. If injury or
be filed immediately with the transportation com

pany and the nearest General Electric Sales Office
should be notified.

It is expected that due care will be exercised
during the unpacking and installation of the breaker
so that no damage will occur from careless or
rough handling, or from exposure to moisture or
dirt. Check all parts against the packing list to be
sure that no parts have been overlooked.
Storage

It is recommended that the breaker be put into

service immediately in its permanent location. If
this is not possible, the following precautions must
be taken toinsuretheproper storage of the breaker:
1.

The breaker should be carefully protected

The breaker should be stored in a clean
location, free from corrosive gases or

fumes; particular care should be taken to
protect the equipment from moisture and
cement dust, as this combination has a very
corrosive effect on many parts.

Unfinished surfaces of rollers, latches etc.,
of the operating mechanism should be coated
with grease to prevent rusting.

If the breaker is stored for any length of time,

it should be inspected periodically to see that
rusting has not started and to insure good mechan

ical condition. Should the breaker be stored under
unfavorable atmospheric conditions, it should be
cleaned and dried out before being placed in service.

(Cover photo 8037386)

These instruetions do not purport to cover all details or variations in equipment nor

prov'dji 5

wJSS

contingency to be met in connection with installation, operation or mowteiwnce. ^Id further
or should particular problems arise which are not covered sufficiently for the purchaser s purposes, the matter should
be referred to the General Electric Company,

GEI-88771 Magne Blast Circuit Breaker

INSTALLATION
Remove the top cover and box barrier.
Do not remove side or front covers. (See
note under Repair and Replacement, page
22.) Make a visual inspection to ascertain

SPRINGS ARE BLOCKED AND THE OPEN

ING SPRINGS HAVE BEEN TRIPPED OPEN
OR MECHANTCALLY BLOCKED.
THIS
PRECAUTION IS REQUIRED TO PREVENT
ACCIDENTAL CLOSING OR TRIPPING.

that the breaker and mechanism is in satis

factory condition.

Check all bearing sur

faces of the mechanism for lubrication.

The closing springs should now be un
blocked.
Rotate the charging shaft until

Refer to section on lubrication page 18
and Figure 16.
2.

the indicator reads "CHARGED" and the

Charge the breaker closing springs man
ually using a 5/8" ratchet wrench to turn
the manual charging shaft (3) Figure 1.
Turning the shaft counter clockwise will

ratchet wheel does not advance. The spring
blocking devices

into the metilclad housing to the test

position.
Operate it electrically several
times. Check the control voltage as de

When the springs have reached the fully
charged position the indicator (5) Figure
2 will read "CHARGED", and the driving
teeth.

Additional turning of the charging

scribed under"CONTROL POWER CHECK"

(Page 16).
4.

Disconnect the test coupler, or remove
breaker from housing, and replace box
barrier and top cover.

If the breaker has been stored for a long

shaft will not advance the ratchet wheel.

Insert the spring blocking devices into

a hole (2) Figure 1 on each side of breaker,

period of time, it is recommended that

and manually discharge the springs against
the pins by pushing the manual close
button (6) Figure 2. The springs are now
blocked and slow closing of the breaker
contacts can be accomplished by again
turning the manual charging shaft with
a 5/8" ratchet wrench.

the insulation be checked with a standard

60 Hertz high potential test.
Insulation Test (Page 18).

volts, remove both the motor leads from
the terminal connection.

insure that the mechanism does not stick

cause damage to the winding insulation.

lever is operated. At this time, also check

DO NOT WORK ON EITHER THE BREAKER
OR MECHANISM UNLESS THE CLOSING

Lubricate the inside silver portion of the
primary disconnect fingers by applying
a thin film of contact lubricant D50H47.

the following adjustments:

Arcing contact wipe (Refer to page 12).
Primaiy contactwipe (Refertopage 13).
Primary contact gap (Refertopage 13).

Failure to dis

connect the motor from the circuit may

or bind during the entire stroke, that it

a.
b.
c.

Refer to

NOTE: If the breaker secondary wiring
is to be giveu -a hi-potential test at 1500

During the slow closing operation check to

latches securely in the closed position, and
that it trips freely when the manual trip

Connect the test coupler to the right hand
secondary coupler or insert the breaker

advance the ratchet wheel and compress
the springs.

pawl will be raised from the ratchet wheel

can now be removed.

The lubricant should extend approximately
one inch (1") from the end of the finger.
7.

Refer to metal-clad instruction book GEI-

88775 for instructions on inserting the
breaker into the metal-clad unit.

DESCRBPTION OF OPERATION
The Magneblast Breaker has two principal com
ponents; the breaker element and the operating

the stored energy type designed to give high speed
closing aiid opening. The mechanism wiU operate

mechanism:

on a-c or d-c voltage as indicated on the breaker

The brewer element is three similar pole units,
each of which includes the current carrying parts,
main and arcing contacts, interrupter, and an
enclosing barrier system that provides insulation

between poles, or phases and to ground. The pri
mary

connections to the associated metal-clad

switchgear are made through the primary dis
connect fingers at the rear of the breaker.

The operating mechanism type ML-13A is of

nameplate.

Closing and opening operations are

controlled either electrically from the met^-clad

unit and remote location, or mechanically by the

manual close and trip buttons on the breaker. All
secondary connections from the breaker to the metal

clad unit are made through the coupler (1) Fig. 3.

A spring release interlock. Fig. 4 is provided
to discharge both the closing and opening springs
when the breaker is withdrawn from or inserted
into the Metal Clad unit.

Magne Blast Circuit Breaker GEI-88771

I" j'']

Fig. 2 (8037380) Control Panel

Fig. 1 (8037382) Manual Charging
1.
2.
3.

Manual Charging Wrench
Hole for Spring Blocking Pin
Manual Charging Shaft

Bevel Gears

Closing Spring

ralrL,

Trip Button

Position Indicator

Racking Screw Shutter

Position Stop Release

Charge-Discharge Indicator

Close Button

7.
8.
9.

Open-Close Indicator
Operation Counter
Racking Screw Hole

10.

Padlock Hole Cover

11.

Hand-Charge Hole Cover

Secondary Coupler
Interlock Switches

Auxiliary Switch
Latch ChecVting Switch

Spring Discharge Roller
Switch Cam

Closing Latch Roller
Closing Latch
Power Switches

Closing Spring

Motor

Control Relay

Spring Blocking Pin

I'l

10 9 8 7 6 5

3 2

Fig. 3 (8037375) Right Side View ML-13A OperaUng Mechanism

GEI-88771 Magne Blast Circuit Breaker

Spring Discharge Stop
Spring Discharge Roller
Spring Discharge Crank
Turnbuckle

Closing Latch Stop
Spring Discharge Stop
Trip Link

Closing Latch Roller
Switch Cam

Switch Striker

Switch Support Bolt
Switch Support
Power Switches

Closing Latch

Switch Support Bolt
Motor Terminal Board

Closing Latch Shaft

Closing Latch Spring
Motor

Latch Monitoring Switch
Latch Switch Support
Spring Release Solenoid
Closing Coil Support

I Lb

: 3?

23 2221 2019 58 17 1615141312 11

Fig. 4 (8037379) Control Mechanism and Spring Discharge Link

3 4

6 7

8 9

Fig. 5 (8037377) Left Side View ML-13A Operating Mechanism
1. Main Shaft Bearing
2. Rear Spring Pin

3. Latching Pawls
4. Positive Interlock Roller

5. Opening Spring
6. Cam Shaft

7. Ratchet Wheel
8. Guide Block

9. Front Spring Pin
10.

Eccentric

11. Closing Spring

Magne Blast Circuit Breaker GEI-88771

Apositive interlock (4) Figure 5 and interlock
switch (2) Figure 3, are provided between the

breaker and metal-clad unit and work with the

The pawl advances the ratchet wheel (7) Figure
5 a few degrees each stroke where it is held in

position by the latching pawls (3). When the ratchet

rack screw shutter to prevent insertion or re

wheel has been rotated approximately 180 degrees

position and to prevent a closingoperation when the

As the ratchet wheel continues to rotate, the spring
load will shift over center and attempt to discharge.
After a few degrees of rotation, the closing roller

moval of the breaker in the unit while in a closed

breaker is not in either the fully connected or

test position. To insure that this interlock will

function during manual, as well as during electrical
operation of the equipment, both mechanical and
electrical blocking is provided. If for any reason

the closing springs should be discharged against
the positive interlock the mechanism will be
jammed and be inoperable. The mechanism can
be released and returned to the reset position

by pushing in on the trip lever (1) Figure 2. It
may require more than normal force to release
the interlock.

An auxiliary switch operator (3) Figure 6
can be provided when required to operate a
stationary auxiliary switch mounted in the metal

the closii^ springs (11) will be fully compressed.

(7) Figure 3, will engage the closing latch(8) and

the compressed springs will be held by the latch
until a closing operation is required. During the
last few degrees of the ratchet wheel rotation the
power switches (9) are opened and the driving pawl
is raised from the ratchet wheel surface. This
allows the motor and driving mechanism to coast
to a natural stop expending all residual energy.

During the time the springs are being compressed
a relay (12) is energized to hold the closing circuit
open. The relay remains energized until the springs
are fully charged and the control switch contacts
are re-set.

The closing springs may be charged manually
if control voltage is lost. A 5/8" ratchet wrench

clad unit.

The mechanism has a high speed gear motor (I)
Figure 7, that compresses a set of closing springs
through the action of an eccentric, ratchet, and
pawl assembly. The rotary action of the motor
is converted to a straight stroke through the eccen

tric (5), and a lever (6) that carries a spring loaded
driving pawl.

can be used to rotate the manual charging shaft
in a counter clockwise direction until the indi

cator reads "Charged" and the driving pawl is

raised from the ratchet wheel. The use of the
ratchet wrench provides for maximum safety
in the event that the control power is suddenly
restored without warning. In this event, the motor
drive will override the ratchet wrench and con
tinues to charge the springs.

Fig. 6 (8037376) Auxiliary Switch Operator

1. Spring Discharge Crank
2. Mounting Bolts

3. Auxiliary Switch Operator
4. Mounting Bolts

5. Secondair Disconnect
6. Treadle Link

GEl- 88771 M^ne Blast Circuit Breaker

Motor

2. Mounting Bolt
3. Retaining Ring
4. Motor Mount
5.

Eccentric

6. Driving Link

Fig< 7 (8037378) Driving Elements)
Closing Operation

The breaker can be closed electrically by
energizing the spring release solenoid (22) Figure
4, or manually by pushing the close button (6)
Figure 2. In either method the closing latch is
rotated from under the closing roller to release

the closing springs (10) Figure 3. The energj'
in the springs is used to rotate a cam (16) Figure
8 and close the breaker through the operating
mechanism linkage. During the closing operation
the mechanism is trip-free at all times. The break

er is held closed by the closing prop (14) moving
into position under the prop pin (13). During the
closing operation the opening springs (17) Figure 9,

the opening springs is released to provide the
required opening speed for successful interruption
of the circuit.

As the breaker opens to interrupt a current, the
are first starts at the arcing contacts (6 & 27)
Figure 10, transfers to the arc runner (4 & 10) and
energizes the blow-out coils (3 & 11). This action
introduces a magnetic field between the pole pieces

5 S: 9) of the interrupter that forces the arc deeper
into the arc chute (8). At the time the arcing con
tacts part a discharge of air is expelled through
the booster tube (28) across the arc.

This air

flow assists the arc transfer and interruption by

are compressed and held readv for an opening

operation with the trip latch (8)'Figure 8 bearing

blowing the arc away from the contacts and into
the arc chute. The magnetic field forces the arc
deeper into the interrupter along the diverging arc

against the trip latch roller (9).

runners.

When the closing operation of the breaker is

The arc chute has a series of interleaving cer
amic fins, Figure 18. As the arc is forced into the

completed and the closing latch is fully reset,

interrupter it is lei^thened in the gradually deep

Figure 4, closes to permit the spring charging
motor to be energized and recharge the closing

electrical resistance of the arc is rapidly increased

the contacts of the latch monitoring switch (20)
springs.

Opening Operation

The breaker can be opened either electrically
by energizing the trip coil (13) Figure 9, or man
ually by pushing the trip lever (1) Figure 2.
In each method the trip latch is rotated off the

trip latch roller, permitting the operating mech
anism linkage to collapse. The energy stored in

ening serpentine path between the fins so that the
and its heat is absorbed by the ceramic material.

The increased resistance reduces the nagnitude
and phase angle of the current and at an early
current zero the arc cannot re-establish itself
and interruption occurs.
Trip Free Operation

If the trip coil circuit is energized while the
breaker is closing, the trip armature will force

the trip latch (8) Figure 8 away from the trip

Magne Blast Circuit Breaker GEI-88771

roller (9) causing the mechanism linkage to collajpse
and the breaker to re-open. The closing cam (16)

16 25 15

10 9

will complete its closing stroke and the springs
will re-charge as in a normal closing operation.

Fig. 8 (0121C8152) sectional Side View of Mechanism
17. Check Nut
Frame
9. Trip Latch Roller
18. Stop Plate
Trip Coil Support
10. Trip Latch Roller Support

11. Cr:^ Shaft
12. Cranks

19* Spring Rod

Cam Follower Roller

13. Prop Pin
14. Prop

Trip Shaft
Trip Latch

15. Drive Shaft
16. Cam

23. Stop Pin
24. Main Shaft Bearing
25. Cam Shaft Bearing

Trip Coil

4.
5.

Trip Armature
Prop Reset Spring

7.
8.

20. Spring

21. Spring
22. Spring Guide

GEI-88771 Magne Blast Circuit Breaker

Fig. 9 (8037378) Bottom View of ML-13A Operating Mechanism
Secondary Disconnect

Trip Adjusting Nut
Manual Trip Lever

Prop Spring
Auxiliary Switch Link

Trip Coil

Trip Latch Spring

Trip Coil Support

Auxiliary Switch

Latch Set Screw

Latch Check Switch

Trip Latch

Latch Check Switch Arm

Trip Coil Support

Trip Arm Screw

Coil Moimting Bolts
Opening Springs
secondary Disconnect

Magne Blast Circuit Breaker GEI-88771

12 II p

n
30 29 28 27 25 25 24 25 22 2!

19 18

17 15 15 14

Fig. 10 (0121C8153) Cross Section of Breaker Pole Unit
1.

Upper Bushing

2.
3.
4.

Blow-out Core
Blow-out Coil
Arc Runner

e! stationary Arcing Contact
7.
8.
9.

Box Barrier
Arc Chute
Pole Piece

10.

Arc Runner

11. Blow-out Coil
12. Blow-out Core

13. Disconnect Fingers
14. Lower Frame
15. Lower Bushings
16. Frame

17. Operating Crank
18. Rear Vertical Barrier

19. Spring Retainer
20. Lower Vertical Barrier

21. Operating Rod
„
^
22. Stationary Primary Contacts
23. Movable Primary Contacts
24. Cup Bearing
25. Yoke

26. Movable Contact Arm Assembly
27. Movable Arcing Contact
28. Booster Tube
29. Connection Bar

30. Booster Cylinder and Piston
11

GEI-88771 Magne Blast Circuit Breaker

ADJUSTMENTS
All^adjustments should be checked during per

BLOCKED.

THIS MEASURE IS REQUIRED TGx<*^

iodic inspections and whenever it becomes nec
essary to repair or replace parts that have become

PREVENT ACCIDENTAL CLOSING ORT^PTNa'^

adjustments are listed in the order in which they

Arcing Contact Wipe

worn or defective while in service. The following
are to be checked after removing the top cover
and box barrier from the breaker.
DO NOT WORK ON EITHER THE BREAKER OR
MECHANISM UNLESS THE CLOSING SPRINGS ARE
BLOCKED AND THE OPENING SPRINGS HAVE
BEEN TRIPPED OPEN OR MECHANICALLY

Refer to Figure 11. Close the breaker until
the arcing contacts just touch. This can be
determined with the use of a circuit continuity
tester such as a light indicator or bell set. In

this position, thegap between thestationary primary

contacts (1) and the movable primary contact (2)

should be.5/16" or greater. This setting has been

J iiaizrw7/T?rr—dm
1

Primary Contact Wipe

Arcing Contact Wipe

Figure 11A. "-OD" ContactStructure (0121C8152)

1
7564

Primary Contact Wipe

Arcing Contact Wipe

Figure 1IB "-ID" Contact Structure (0132C2794)
Figure 11 Contact Adjustments
1.

Stationary Primary Contacts

Movable Primary Contacts
3. Buffer Block
4. Stationary Arcing Contacts
2.

5. Movable Arcing Contacts
6. Contact Arm
7. Throat Baffle

M^ne Blast Circuit Breaker GEI-88771
made in the factory and no adjustment is provided.

A wipe of less than 5/16" is an indication that toe
arcing contacts need to be replaced. When making
this check, see that the movable arcing contact (5)
passes between the probes on the upper arc runner
without touching. On toe "-ID" design, also check
for clearance between the arcing contact (5) and
the slot in the throat baffle (7) during entire stroke
of the movir^ contact assembly.
Primary Contact Wipe

Refer to Figure 11, when the breaker is closed
the stationary primary contacts (1) should rise
from 1/4" to 5/16". Before checking this dimen-

sion be sure the mechanism is re-set so that

the prop pin (13) Figure 8 is resting on toe prop.

To obtain toe proper contact adjustment, open

toe breaker and, referring to Figure 12, loosen the
check nut (13)andtumtheadjustingnut(12). Screw

ing toe adjusting nut toward toe operating rod
(11) will decrease the primary contactwipe, toward
the end of the stud (14) will increase it. Tighten
the check nut, close toe breaker and recheck
toe wipe. With toe primary contact wipe cor

rectly adjusted, the clearance between the contact
arm (6) Figure 11 and the buffer block (3) should

be 1/16" or greater when the breaker is fully
closed.

Priman' Contact Gap

Refer to Figure 12. With the breaker closed,

press the manual trip buttonallowingthebreakerto
trip open normallv. Do not force toe contacts
open wider by hand. Thegap between toe stationary
primary contacts (4) and the movableprimary con
tact (6) measured between the closestpoints, should
be 3-5/8" to 3-15/16". To change this gap, loosen

the check nut (17), Figure 8, and turn the adjusting
nut (18) on stud (19). Screwing the adjusting nut
down will decrease the primary contact gap.

T^hten the check nut and re-measure toe contact
gap (close and trip the breaker before checking
the measurement). Whenever the primary contact

gap is changed, toe primary contact wipe should
be rechecked and, if necessary, readjusted.

WHEN WORKING ON THE MECHANISM INTHE
CLOSED POSITION, KEEP FINGERS CLEAR OF
THE LINKAGE, AS ACCIDENTAL TRIPPING CAN
CAUSE SEVERE INJURY.

Trip Latch Wipe

Refer to Figure 8. The wipe of toe trip latch

(8) on the trip roHer (9) should be from 3/16"

to 1/4". This can be measured by putting a film

of t^rease on toe latch (8), closing the breaker

part wav, and tripping. The mechanism has the

proper trip latch wine when the latch rests against
toe stop pin (23). *No adjustment is provided and
a visual inspection is usually all that is required. If
this setting is not correct, look for insufficient
travel of toe trip shaft (7).
Trio Armature Travel

Fig. 12 (8037374) Primary Contact Adjustment
1.

Contact Spring

2.
3.

Buffer Retainer
Buffer Block

4.
5.

Stationary Primary Contact
Movable Arcing Contact

Movable Primary Contact

7.
8.
9.

Arcing Contact Bolts
Primary Contact Bolts
Cupped Hinge Washer

10.

Hinge Nut

11.

Operating Rod

12.

Adjusting Nut

13.

Check Nut

14.

Operating Rod Stud

Refer to Figure 8. The trip armature (4)
should have 7/32" to 9/32" travel before toe trip
latch (8) starts to move. This can be adjusted by-

moving toe trip coil support (2) and/or byadjusting
the trip armature screw (14), Figure 9. A locking

screw located behind toe trip armature screw must
first be loosened. Retighten locking screw after
making adjustment.
Release Latch Wipe

Refer to Figure 4. The wipe between the release

latch (14) and roller (8) should be 3/16" to 1/4".
If re-setting is required, loosen, set, and re-

tighten adjustment nut and screw (5).

GEI-88771 Magne Blast Circuit Breaker

Release Latch Monitoring Switch
Refer to Figure 4.

The release latch must be

fully re-set and the latch monitoring switch (20)
operated before the motor will start. When the latch

is fully reset the clearance between the switch

striker arm and the switch mounting bracket (21)
is 1,-32" or less, this can be adjusted bv bending
the striker arm.

advance the ratchet wheel (7) sufficiently on each
stroke to allow the latching pawls ('3) to fall

into the ratchet teeth. This should be checked with'*
the closing spring load against the driving membersWith the mechanism unblocked, hand charge the
closing springs with the manual charging wrench
until they are slightly more than half chained,

blowly rotate the charging wrench until the driving

pawl has traveled through its return stroke and

check the maximum clearance between the pawl
and the ratchet tooth. Rotate the charging wrench

Motor and Relay Switches

Refer to Figure 4. With the closing springs

blocked rotate the switch cam (9) until the switch
striker (10) has traveled the maximum amount

(about 180 degrees rotation of cam). At this point

the clearance between the striker and the switch
support (12) should be 1/32" or less. This can be

until the driving pawl has advanced the ratchet tooth
to its maximum travel. Now check the clearance

between the ratchet toothand the latching pawl. The
clearance should be approximately equal for both

the driving and latching pawls and not less than
.015" in either case.

adjusted by loosening the switch support mounting
bolts (15) and rotating the support.

springs must first be fully charged and blocked.

Interlock Switch Wipe

and move entire motor assembly down if the

If adjustment is required for either pawl the

Loosen seven motor support bolts (2) Figure 7

Refer to Figure 13. With the positive interlock

in the reset, or normal position the clearance
between the interlock switch arm (4) and the switch
mounting plate should be 1/32" or less.

This

clearance is under the minimum at the latching

pawls, and up if the clearance is under the minimum

at the driving pawl. Move the motor assembly

approximately twice the dimensional increase re

can be adjusted by bending the switch arm.

quired at the pawl. Be certain the motor assembly
is moved straight up or down and tighten the

Driving Pawl Adjustment

to assure proper alignment.

Refer to Figure 5.

one bolt on the left of the mounting frame first

The driving pawl must

Fig. 13 (8037375) Interlock Switcnes
Manual Trip Lever
Interlock Shaft

After tightening

the remaining bolts the springs should be released
and the clearance again checked as described above.

.A.uxiliary switch
Switch Support

Secondary Coupler

Latch Check Switch

Interlock Switch Arm

Switch Arm

Interlock Switch

Trip Shaft

Magne Blast Circuit Breaker GEI-88771

AUXILIARY DEVICES

Arcing contact wipe: 5/16" or greater

gap at primary contacts. .
Primary contact gap: 3-5/8" to

Latch Checking Switch

Refer to Figure 14. Charge the closing springs
sufficiently to reset the mechanism linkage. Rotate
the trip latch (4) by pressing the manual trip lever
to open the latch checking switch (2). Allow the
trip latch to reset slowly and determine the point

at which the contacts are made by using a circuit

The contacts of the latch checking switch should

latch resting against stop pin.
e.

just make when the gap between the trip latch
(4) and the stop pin (5) located on the latch roller
link- (7) is 1/16". There should be a minimum of

1/64" between the switch arm (3) and the switch
support (1). To obtain adjustment of the latch check

ing switch, bend the latch checking switch arm (3).

ment is provided.

For ease in reviewing the adjustments, the
following are recapitulated:

Release latch monitoring switch: Max
imum clearance 1/32".
Motor and relay switch:
maximum
clearance 1/32".
Interlock switch: maximum clearance
1/32".

Latch checking switch contacts make

clearance to ratchet teeth .015".

when the gap between the trip latch
and the stop pin is 1/16".
Auxiliary switch operator - 14-3/8
to 14- 7/16".

Check all nuts, washers, bolts, cotter pins,
and terminal connection for tightness.

Inspect all wiring to make sure that no
damage has resulted during installation, ^d
test for possible grounds or short circuits.

See that all bearing surfaces of the mech
anism have been lubricated. Refer to the
section on LUBRICATION. (P^e 18 and

Inspection and Test

Release latch wipe: 3/16" to 1/4".

Driving and Latchii^ Pawl: minimum

Refer to Figure 6. With the breaker in the
closed position, the vertical distance "A" from the

Trip armature travel 7/32" to 9/32 .

Auxiliary Switch Operator

line should be 14-3/8" to 14-7/16". This adjustment
is set and pinned at the factory and no adjust

3-15/16".

Trip latch wipe: 3/16" to 1/4" with trip

continuity tester (light indicator, bell set, etc).

top of the roller on the crank (3) to the floor

Primary contact wipe: 1/4" to 5/l6".

Figure 16K

Operate the breaker slowly with the m^ual

charging wrench and note that there is no
excessive binding or friction and that the

breaker can be moved to the fully opened and
fully closed positions.

See that any place where the surface of the

paint has beendamaged is repaintedimmed
iately.

Check the trip coil plunger and the release

coil plunger to see that they move freely.

Opening and Closing Speeds

The closing speed of the arcing contact of the
breaker should be a minimum of 11 feet per second.
8

This represents the average speed of the movable
arcing contact from a point 3" before the tip is
tangent to the lower surface of the probes on the
rear arc runner to the tangent position.

The opening speed of the arcing contact should
be a minimum of 12 feet per second. This repre

sents the average speed over 3" from the point
when the tip on the movable arcing contact is

Figure 14 (0121C8152) Latch Checking Switch
. Switch Support
. Latch Checking Switch

5.
6.

7.
8.

Switch Arm

. Trip Latch

Reset Pin Stop
Latch Roller
Latch Roller Link
Latch Roller Pin

tangent to the lower surface of the probes on the

rear nmner.
Proper servicing and lubrication
of the breaker and its operating mechanism should
maintain these speeds and no adjustment is provided.

GEI-88771 Magne Blast Circuit Breaker
Control Power Check

2i^v
if8v

d-c

ilOv

d-c

125v

a- c

220v

Q-C

160

a-c

ito
95
190

250v
115v
230v

d-c

a-c
a-c

to
90

50v
115V
130V
230V
260V
125V
25OV

Trippi..^

11
26

d-c

d-c 120

d-c ilo
a-c
a-c

95
190

simultaneously, the closed circuit voltage at the
closmg coil or motor of each breaker must fall

Electrical closing or opening is accomplishedbv

Rang-e

d-c

When two or more breakers operating from the

same control power source are required to close

within the specified limits.

Closing
Range

Yol "cage

If the closed circuit voltage at the terminals
of the coil or motor does not fall in the specified
rai^e, check the voltage at the source ofpower and
line drop between the power source and breaker.

30v
60 V
- 125v
- llOv

25OV
2tov
125 V
25OV

energizing the closing or trip coil circuit. Control

d-c
d-c

d-c

switches are provided for this purpose on the
metal-clad unit. It is also possible to trip or close

the breaker manually by pressing the manual trip
lever (1) Figure 2 or the manual close button (6).

d-c

d-c
d-c
a-c
a-c

GENERAL tViABNTENANCE
General

Safe and dependable service from electrical ap
paratus and power systems is contingent upon re
liable performance of power circuit breakers. To
obtain maximum reliability the breaker should be
inspected and maintained on a regular schedule.

The breakers are designed in accordance with ap

plicable standards which require that thev be
capable of performing up to 5000 operations for
1200 ampere breakers and 3000 operations for 2000
ampere breakers switching rated continuous cur

rent before any replacement of parts should be

necessary.

This requirement is based on the

breakers being serviced, or maintained, at least
every 2000 operations, or once per year, whichever
comes first. If the breaker is adso required to
interrupt fault currents during this period of time
additional maintenance and replacement of parts

operating company and will depend onthe application
of the breakers and the operating conditions.
Factors which shouldbe consideredare: Importance
of the breakers tooverall plant or system operation-

number of operations and magnitude of currents
switched by breaker; frequency of fault inter
ruptions; and the atmospheric conditions in which
the breaker normally operates. Extreme conditions

of dust, moisture, corrosive gases etc., can indicate
that inspection and maintenance will be required

more frequently than every 2000 operations. Ven'
clean dry operating conditions with low current
switching duty can justify a longer period of time
between inspections. Any time a breaker is known

to have interrupted a fault at or near its rating it is

recommended that the breaker be inspected and
necessary maintenance be performed as soon after

the interruption as is practical. The following

may be necessary.

instructions give the items that should be included
m an inspection and general recommendations on the

BEFORE ANY MAINTENANCE WORK IS PER
FORMED, MAKE CERTAIN THAT ALL CONTROL
CIRCUITS ARE DE-ENERGIZED AND THAT THE
BREAKER IS REMOVED FROM THE METAL-CLAD
UNIT. DO NOT WORK ON THE BREAKER OR
MECHANISM WHILE IN THE CLOSED POSITION
UNLESS THE PRQP AND TRIP LATCH HAVE
BEEN SECURELY WIRED OR BLOCKED TO PRE
VENT ACCIDENTAL TRIPPING. DO NOT WORK
ON THE BREAKER OR MECHANISM WHILE THE
SPRINGS ARE CH.ARGED UNLESS THEY ARE
SECURED IN THAT POSITION BY THE MAIN
TENANCE SPRING BLOCKING DEVICE.

maintenance of breakers.

Periodic Inspection

The frequency of the inspection and maintenance
operations required should be determined by each
16

Interrupters

Since there are no moving parts, theinterrupters
of a magneblast breaker will normally require

little or no inspection unless there is' evidence
of damage to the arc chutes sides or contamination
in the throat area. If either of these conditions are
present the interrupters should be removed from the
breaker and the following points noted:
1.

The throat area of the interrupter should
be cleaned with sandpaper (Do Not use
emery cloth or other metallic abrasives).
All flat areas on either side of the movable
arcing contact travel should be sanded.

Do not sand or otherwise attempt to clean

Magne Blast Circuit Breaker GEI-88771
be repaired or the part replaced.

the ceramic fins of the arc chute sides.

Heavily contaminated parts should be re
placed.

Interrupter Removal And Replacement

Cracks which have formed in the fins of the
arc chute are to be expected in ceramic
materials of this type when subjected to

To "remove an interrupter, open the breaker
contacts and remove the top cover and box barrier.

the severe heat of an arc.

Referring to Figure 15, loosen the two rear support
bolts (6) and the one front support bolt (3) using

These cracks

a standard 3/4" wrench.

do not interfere with the operation of the

Slide the complete

interrupter assembly approximately 3/8" toward

device in any way and should be disregarded.

the rear and remove by lifting straight up.

If the arc chute has suffered any mech^ical
injury due to dropping or accidental striking,
resulting in the actual breaking off of fins,
replacement will be necessary. Small

To reassemble the interrupter to the breaker,

lower the interrupter into the front support (2) and
over the rear support (7). Slide the interrupter
assembly toward the front making certain that the
cut-out in the interrupter support engages the bolt
(6) On the "-ID" design check to assure that the

broken corners on the exhaust end of the

arc chute sides will not interfere with its

performance and can be disregarded.

throat insulation (7), Figure 18 in toe interrupter
extending from the stationary contact support

is oroperlv positioned within toe throat barrier
The plastisol flexible covering for the pole
interrupter support (10) ahouldbe inspected

(5), Figure 21.

for breaks in the insulation. If there are
holes or breaks in the insulation they should

"^1

Tighten the supporting bolts (3) and (6), Figure

o
^8

1.
2.
3.
4.
5.
6.
7.
8.
9.

Interrupter

Front Interrupter Support
Front Support Bolts
Booster Cylinder
Rear Vertical Barriers
Rear Support Bolt
Rear Interrupter Support
Movable Arcir^ Contact
Stationary .\rcing Contact

10. Primary Finger

11. Movable Primary Contact
12. Contact Arm

13. Front Vertical Barriers

m / 0

•.

Fig. 15 (8037385) Interrupters partially removed showing accessibility of Arcing Contacts

GEI-88771 Magne Blast Circuit Breaker

15.

These bolts serve as both the electrical and

mechanical connections between the bushings and
the arc runners within the interrupter. Check
that the movable arcing contact (8) passes between
the probes on the rear arc runner (5) Figure
18 without touching.

may have been affected by moisture absorption.

If the breaker secondary wiring is to be given

a high potential test at 1500 volts, remove both of
the motor leads from the terminal board. Failure

to disconnect the motor from the circuit maycause
damage to the winding insulation.

Breaker Contacts

Bv removing the too cover and the box barrier

the movable and stationary primary contacts and

Lubrication

the movable arcing contacts can be inspected. The
stationary arcing contacts can be inspected only

In order to maintain reliable operation, it is
important that all circuit breakers be properly
lubricated at all times. Most of the bearings and

a fine file^
made smooth with
After completing inspection of the contacts,

pat will require no maintenance and will last the
life of the equpment. Only few bearings and surpces Imted in the chart. Figure 16, require
lubrication. These have been properly lubricated
durmg assembly at the factory, using the finest
grades of lubricants available. However, even the
finpt oils and greases have a tendency to oxidize
with age, as evidence by hardening and darkening

^ter removing the interrupter. If the contacts are

AlhroSTMENTS^^ adjustments as specified under
Mechanism

A careful inspection should be made to check

for loose nuts or bolts and broken retaining rings.

rolling surfaces utilize a new type ofdry lubrication

in color. Elimination of the hardened lubricant
p essential for the proper operation of circuit

All cam, roller, and latch surfaces should be
inspected for any evidence of damage or excessive

breakers. Also frequent operation of the breaker
causes the lubricant to be forced out from between
the bearing surfaces. A simple lubrication will

close the breaker several times to make certain
that the mechanism operates freely throughout its

be mistaken for more serious trouble.

as specified under ADJUSTMENTS,

A definite lubrication schedule should be set
up talung into consideration thefrequencyofopera-

wear. Lubricate the mechanism as outlined below,
then, using the manual charging wrench, open and
entire stroke.

Check the mechanism adjustments
Check the

control wiring for tightness of connections and
damaged insulation.
Bushings and Insulation

The surface of the bushings should bekept clean
unmarred to prevent moisture absorption,
u the insulation surface should become damaged,

it should be sanded and cleaned, and should be
refimshed with either clear varnish or clear
resm. .Allow to dry smooth and hard.

All other insulation parts on the breaker should
be kept clean and dry. Smoke or dust collected

between inspection periods should be wiped off

and if dampness is apparent, heaters should be
installed in the metal clad switchgear to insure
dryness.
' Insulation Test

When insulation has been repaired or replaced,

or vmen breaker has been operating in adverse
moisture conditions, it is recommended that the
insulation be checked before the breaker is placed

back in service. A standard 60 hertz high potential

test at 14,000 volts RMS for one minute will nor
mally indicate whether the breaker is satisfactorv

pten clear up minor disturbances which might

tion of the breaker and local conditions.

It is recommended thatlubrication ofthebreaker
pd ite operating mechanism be a part of the per
iodic inspection and maintenance program,with not
more man a two year period between lubrications.

It IS also recommended that all circuit breakers
be operated at regular intervals, at least once
a year, to insure the lubrication is in good
condition and the breaker is operable.
divided into
po mettods of lubrication. The first method
out

lines the maintenance lubrication which should be
performed at the time of periodic maintenance, and
requires no disassembly. The second method out

lines a lubrication procedure similar to that per

formed on the breaker at the factory, and should be
used when a general overhaul of the breaker is

necessary.

General Electric Lubricants D50H15 andD50H47

are available in 1/4 lb. collapsible tubes. It is

o^daHo^^*^ to insure cleanliness and to prevent
METHOD OF CLEANING

for seiwice. With the breaker contacts in the fully

opened position, apply the test potential to each
terminal of the breaker individually with all other
terminals and the breaker frame grounded. After
high potential tests are made on organic insulating

materials, these materials should be inspected for

current
and necessary
action
must K
be taken to
repairpaths,
or replace
insulation
that
18

BEARINGS

• .^hf"®ver
cleaning
of bearings
required,
as
indicapd
in the
lubrication
chart,isthe
following

procedures are recommended:

Sleeve Bearings

The sleeve bearings used throughout the linkage

Mapie Blast Circuit Breaker GEI-88771

LUBRICATION AT
PART

MAINTENANCE

ALTERNATE LUBRICATION

(REQUIRES DISASSEMBLY)

PERIOD

Sleeve Bearings - links,
trip shaft, etc. (Teflon
coated bearings)
Sleeve Bearings - main crank
shaft, driving pawl lever.

No lubrication
required.

No lubrication required.

Light applica-:

Remove bearings or links

(Bronze or cast iron)

tion of machine
oil SAE 20 or
SAE 30.

and apply D5OHI5 lubri
cant liberally.

Contact Arm Hinge Assembly

No lubrication

Wipe clean and apply

Cup bearing

Loose rings between bushing

required.

clean per instructions

D50H47.

and contact arm.

Roller and Needle Bearings

Ground surfaces such as
cams, ratchet teeth, etc.

(Surfaces coated with M0S2)

Ground surfaces such as

latches, rollers, prop,
etc.

Silver plated contacts and
primary disconnect studs.
Booster Cylinder

Light applica

Clean per instructions

tion of machine
oil SAE 20 or
SAE 30.

and repack with D5OHI5

No lubrication
required.

No lubrication required.

lubricant.

Wipe clean and

Wipe clean and apply

apply D5OHI5

D5OHI5 lubricant.

lubricant.

Wipe clean and

apply D50H47.
Do not

Wipe clean and apply
D50H47.
Do not lubricate.

Lubricate.

Arcing Contacts

Do not

Do not lubricate.

Lubricate.

Figure 16 Lubrication Chart

GEI-88771 Magne Blast Circuit Breaker

utilize Teflon surfaces and do not require lub
rication. After a number of operations, the sur
face will acquire a thin black film. Do not remove
this film unless there is evidence of outside con

factorily with petroleum solvent or a similar

cleaner and a stiff brush. Follow the procedure
outlined above using a light machine oil and G-E
lubricant D50H15 before reassembling the inner

taminates, such as dry or hardened grease. If

race and shaft.

contaniinants are nresent thev should be rempved

by immersing the link and bearing in clean petro

Rolling Surfaces

leum solvent, or similar cleaner, and using a
stiff brush. Do not remove the bearings from the
links. DO NOT USE CARBON TETRACHLORIDE.

A number of rolling and rubbing surfaces in the
mechanism have been lubricated with a baked-on

The hinge of the primary contact arm (22)

Figure 21, should be disassembled, cleaned, and
lubricated with G-E D50H47 lubricant at general
overhaul periods.

The main shaft bearings (24) Figure 8 and the

bearings in driving pawl lever (6) Figure 7,
should be removed, cleaned, and lubricated with
G-E D50H15 lubricant at general overhaul periods.

dry, molybdenum disulfide coating. Thislubrication,
which can be recognized by its dark, almost black

color (e.g. Face of switch cam (9) Figure 4) re

quires no maintenance and should last the life of
the breaker.

Other rolling or rubbir^ surfaces that are not

lubricated with molybdenum disulfide should have

the dried, dirty grease removed and a thin film
of fresh lubricant D50H15 applied.
MAINTENANCE

Roller and Needle Bearings

Refer to Figure 8. The cam follower bearings
(6). latch roller bearing (9), and cam shaft bearings
(25) should be removed from the mechanism and
the inner race disassembled. They should then be

placed in a container of clean petroleuin solvent
or similar cleaner.

DO NOT USE CARBON

TETROCHLORTOE. If the grease in the bearings

has become badly oxidized, it may be necessary to
use alcohol (type used for thinning shellac) to

Magne-Blast breakers used for switching arc
furnaces or capacitors will require more^ frequent
and more detailed inspection and maintenance
because of the repetitive nature ofthe applications.

The following schedule is recommended for such
breakers:
A.

Every 500 Operations,or EverySixMonthsWhichever Comes First:

remove it. Ordinarily, by agitating the bearmgsm

with bare hands as deposits from the skin onto the

2. Wipe all insulatii^ parts cleanofsmoke
deposit and dust with a clean drycloth,
including the bushir^s, and the inside

the cleaning solution, and using a stiff brush to
remove the soUd particles, the bearings can be
satisfactorily cleaned. Do not handle the bearings
bearir^s are inductive to corrosion. If the bear
ings are touched, the contamination canbe removed
by washing in alcohol. After the bearings have
been thoroughly cleaned, spin them in clean new
light machine oil until the cleper or solvent
is entirely removed. Allow this oil to dram off and
then repack them immediately with G-E lubricant
D50H15 being sure all metal parts are greased.

of the box barrier.

ed by using sandpaper. This cleaning
rupter is removed. The fins on the

arc chute sides should not be cleaned.
Whenever the interrupter is removed,
loose dust and dirt should be blown
out before replacing arc chutes. Throat
insulation which is heavily contaminated

If it becomes necessary to clean the

bearir^s in alcohol (shellac thinner), be sure

the alcohol is perfectly clean, and dp not allow the
bea.rings to remain in the alcohol more than a few
hours. If it is desirable to leave the bearings m
the alcohol for a longer time, an inhibited alcohol
such as is used for anti-freeze should be used.
Even then the bearings should be removed from the

alcohol within twenty-four hours.

Precautior^

should be replaced.

Every 2000 Operations, or Every Six Months
Whichever Comes First:

against the toxic effects of the alcohol must be
the alcohol in a well ventilated room; excessive

oil, draining and repacking with lubricant DaOHlo
should follow immediately.

Bearings that are pressed into theframeor other

members such as the motor support (4) Figure 7
should not be removed. After removing the shaft
and inner race the bearing can be cleaned satis
20

In addition to the servicing done each

500 operations, the following inspection

should be made and work done when
required.

exercised by wearing rubber gloves and by using

exposure to the fumes is sometimes unpleasant
to personnel. Washing the bearings in

All flat parts in the throat area of the
interrupters shouldbe thoroughlyclean
should be performed anytime the inter

The inner races should then be assembled.

NOTE;

Remove the top cover and box barrier.

Primary Contacts (19 and20Figure 21).

Inspect the condition of the stationary
contact fingers and movable contact
blocks. Badly pitted or burned contacts

should be replaced. (Note: Burne(^^

primary contacts indicate the probable
need for arcing contact replacement.)
If the contact surfaces are only rough-

Magne Blast Circuit Breaker GEI-88771

ened or galled, they should be smoothed
with crocus cloth or draw filed. After

tion of insulation, blow-out coils, arc

contact dressing the primary contacts
should be greased lightly with D50H47.

become contaminated by arc products.

Arcing Contacts (2 and 7 Figure 21k

runners

JUSTMENTS, the contacts should be
The

contacts

inspected for uneven wear and/or dam

original metal thickness as a result of
arc erosion.

Do not grease the arcing contacts under

should be replaced.

The breaker and operating mechanism

NOTE: Fine cracks may develop on the

cam, latch and roller surfaces should

fins of the arc chute sides. This is to
be expected with ceramic materials

be inspected for damage or excessive
The buffer blocks and their

when subjected to the high heat of an
arc and may be disregarded vtnless

retainers on the bottom of the stationary
contact support should be inspected for

they are long and present a possibility
of fin sections breaking completely off.

possible need of replacement.

Small broken corners on the exhaust
end of the arc chute will not interfere
with its performance and can also
be disregarded.

The contacts of the control relay (12)
Figure 3, should be inspected for wear
and cleaned if necessary.

Lubricate the breaker operating mech
anism in accordance with instructions

under LUBRICATION, page 18 and the
lubrication chart Figure 16.

Inspect all wiring for tightness of con
nections and possible damage of in

The contact ring shotild be inspected

Mter the breaker has been serviced,
it should be operated manually to be
sure there is no binding or friction

(24).

and tliat the breaker contacts can move

to the fully opened and fully closed
positions.
Its electrical operation
should then be checked using either
the test position or the test couplers.
C.

After Every 10.000 Operations:

In addition to the servicing done each
2000 operations, the interrupters should
be removed from the breaker and dis

assembled to permit a detailed inspec-

The cup bearing (23) Figure 21 and the
contact ring at the hinge point of the
contact blade should be disassembled,
inspected, cleaned, and relubricated
with G-E contact lubricant D50H47.

for wear and replaced when reduced
in thickness to less than 1/32". When
reassembling the cup bearing, be sure
toe cotter pin is properly assembled
in the castle nut on the hinge pin

sulation.

Any parts damaged or severely burned
and/or eroded from arc action should
be replaced.

should be carefully inspected for loose
nuts, bolts, retaining rings, etc., all
wear.

Insulating material that is carbonized

and cannot be satisfactorily cleaned

SPECTION AND TEST. The necessary
readjusments should be made as de
scribed under ADJUSTMENTS.

Check the stationary arc contacts to
assure that the arcing contacts are in
good condition and that their connections
are tight.

any circumstances.

justments as summarized under IN

The arc runners should be inspected
area has been reduced' to 25% of the

tact condition indicate a need for re

Check the breaker and mechanism ad

should be checked for

and replaced when anv part of their

vicing unless inadequate wipe or con

can

The blow-out coils should be carefully

connections
tightness.

age using a mirror to inject the

placement. If the interrupters are re
moved, the contact braids, and other
parts subject to arcing should be check
ed for possible cleaning or replacement.

which

coils are not fully insulated from each
other, the coils should be replaced. All

should be

stationary contacts. Normally it will
not be necessary to remove the inter
rupters for this 2000 operation ser

assemblies

examined and if the insulation has been
cracked, shrunk or eroded from arc
action and heat so that the turns of the

When the arcing contact wipe is less
than the minimum specified under AD
replaced.

and

This assures proper contact

pressure at the hinge.

Every 20,000 Operations or Approximately
Every Five Years - Whichever comes first:

The breaker should be given a general
inspection and overhato. as required.
All excessively worn parts in both the
mechanism and breaker should be re

placed.

Such wear will usually be

intocated when toe breaker cannot be
adjusted to indicated tolerances. This

GEI-88771 Magne Blast Circuit Breaker
overhaul and inspection is more detail
ed and will require disassembly of mech
anism

and breaker operating parts.

All roller and needle bearings in toe
operating mechanism should be dis

assembled, cleaned, and repacked with
G. E. lubricant D50H15 as described
under LUBRICATION.

only.

However, when it is necessary to remove

toe side covers and front cover, they should be
removed as an integral unit. Whenre-assembling,
the dowel pins will reposition the covers to assure

satisfactorj- alignement within toe metal-clad unit.

ARC CHUTE (to inspect or replace blow-out coils
and arc runners):

The stationary primary contact fingers

(19) Figure 21, should be disassembled
and the silver-plated pivot area of the
contact and contact support cleaned and
lubricated with G-E. lubricantD50H47.

In general, repair work can be accomplished
with the removal of toe top cover and box barrier

The breaker and operating mechanism
should be serviced as described for

every 2,000 operations and properly
adjusted before being put back into
service.

With toe breaker open and the closing springs
in the blocked position, remove the top cover
and toe box barrier (7), Figure 10. The interrupter
can now be removed as described under REMOVAL
ANT) REPLACEMENT page 17.
To disassemble the interrupter after it has been
removed from the breaker, proceed as follows:

NOTE:

When disassembling the arc chute and

its components some small washers, spacers, etc.,

REPAIR AND REPLACEMENT

will be foimd that cannot be identified in these
instructions.
Care should be taken to collect

This section covers the proper method of

and identify these items so they can be reassembled

removing and replacing those parts of the breaker
subject to damage and wear that may require repair
or replacement at the installation. IMPORTANT:

UPON COMPLETION OF ANY REPAIR WORK. ALL
BREAKER AND MECHANISM ADJUSTMENTS MUST
BE CHECKED. Refer to toe section on INSTALLA

TION, payingparticular attention to ADJUSTMENTS

correctly.

Remove toe c^s and assembly bolts (7,
9, 11, t 13), Figure 17.

Remove the side brace (5), and pole pieces
(3 6i 6).

and FINAL INSPECTION.

1. Assembly Bolts and Bushing
2. Assembly Bolts
3.

Rear Pole Piece

4. Assembly Bolt
5. Side Brace
6. Front Pole Piece

7. Assembly Bolt
8.

Front Brace

9. Assembly Bolt

10. Riar Interrupter Support

11. Insulating Cap
12. Side Shield

13. Assembly Bolt

14. Front Interrupter Support
15. Assembly Bolts
16. Assembly Bolts

Fig. 17 (8039601) Interrupter Assembly

Magne Blast Circuit Breaker GEI-88771

Rear Arc Runner Spacer
Rear Arc Runner Assembly
Blowout Core
Blowout Coil
Rear Arc Runner
Arc Chute Side

Throat Insulation
Front Runner Shield
Front Arc Runner
Blowout Coil
Blowout Core

Front Insulation

Front Arc Runner Assembly
Front Coil Connection

Front Arc Runner Spacers

Fig. 18 (8039603) Interrupter Assembly with Side Removed

Rear Mounting Support

2.
3.

Connection Bolt
Insulation Plate

Rear Arc Runner Assembly

Side Shield

Front Coil Connection

Connection Nut

Front Mounting Support

Fig. 19 (8039604) Interrupter Assembly

Front Arc Runner Assembly

aEI-88771 Magne Blast Circuit Breaker
arc chute sides measuredatleastl"infrom

the back end of the arc, chute (See Figure
20) should be 1/64" to 3/32".

Check to insure that electrical connections
to the blowout coils are tight.

••7'si-

When reassembling the arc runner as
semblies, check that the spacers are cor
rectly installed.

Before boltii^ the rear supports in place,

••"•.iyr

make

certain

that the rear arc runner

assembly is tight against the arc chute
side so that the gap between the throat
insulation (7), Figure 18, and the arc
chute sides (6) is a minimum.

Make certain that the electrical connections
(2 & 8), Figure 19 are tight.

Reassemble the arc chute on the breaker as
described under INTERRUPTER REMOVAL AND
REPLACEMENT, page 17.
CONTACTS

Fig. 20 (8029373) Arc Chute Fin Spacing

Open the breaker and remove the top cover,
box barrier, and interrupters as previously de
scribed.

To remove the rear interrupter support
(10) remove the assembly bolt (1), ana
the bolted connection (2) Figure 19 between
the rear interrupter support and the blow

A. Stationary Arcing Contacts (2), Figure 21.

out coil.

To remove the contacts, proceed as

follows:

Disconnect the contact braids (4) from
the contact fingers by removing two
bolts and locking plates (14).

Grasp the front end of the contact
fillers with pliers and pull contact

Remove the assembly bolt (16), Figure 17
to remove the front brace (8).

5. Remove the front interrupter support (14)
by removing the assembly bolts (15) and

assembly forward to remove from stud

the connection nut (8), Figure 19.

assembly.

6. At this point, the side shields (12), Figure
17, and the arc runner assemblies (4 & b),

Figure 19 can be removed.

Further disassembly of both the rear and

To disassemble stud plate from contact

Reassemble in the reverse order, make

front arc runner assemblies can be done by

removing the various screws and assembly
bolts (not illustrated) as shown in Figure
The arc chute sides (6) Figure 18, can
also be separated for inspection after
removing assembly bolts (2 & 4), F^ure
17.

Reassemble the interrupter in the reverse order.

and in line.

2. The gap between the fins at the rear of the

Remove the assembly bolts (8) making

note of quantity and location of shims
and spacers used between contacts and
contact arms.

Reassemble in reverse order, re-using
the shims and spacers.

The fins of the arc chute sides should be

equally spaced and aligned before bolting
together. The front edge (along the runner
of the two arc chute sides shouldbeparallel

sure locking plates are properly re

Movable Arcing Contact (7) Figure 21.

The following items should be noted during re
assembly:

support, remove two bolts (3).
assembled with bolts (14).

18.

To disassemble braids from stud

plate remove one bolt (13).

Close the breaker slowly to check
that the movable arcing contact is

approximately centered on the station
ary arcing contact and that it does

not rub on either side of the throat

Magne Blast Circuit Breaker GEI-88771

Ik..

r-id
I

^iii«

i Wm^-

Fig. 21 (8037373) Contact Assembly
Bolts for Contact bupport
14. Connection Bolt

Stationary Arcing Contact Asm.
Mounting Bolt
Flexible Braid

Contact Support
Buffer

15. Arcing Contact Finger

16. Insulation Plate

.17. Contact Spring

18. Buffer Retainer

p. Stationary Primary Contact
20. Movable Primary Contact

Movable Arcing Contact
Assembly Bolts
Front Support Bolt
Assembly Bolts

23. Cup Bearing

Rear Support Bolt
Bolt for Flexible Braids

24. Hinge Pin and Nut
25. Operating Rod
26. Adjusting Nut

Rear Interrupter Support

21. Connection Bar
22. Contact Arm

GEI-88771 Magne Blast Circuit Breaker

NOTE: Whenever it is found necessary

2. Pry contact arms (22) apart enough to
disengage pivot pins of piston assembly
(28), Figure 10, allowing piston todrop

of a breaker it is recommended that
both the stationary and movable con

Rotate toe two parts of toe contact arm

Reassemble in reverse order.

barrier (7) Figure 11.

to replace arcing contacts on

down into its booster cylinder.

pole

tacts on that pole be replaced at the

same time.

C. Stationary Primary Contacts (9), Figure 22.
1 Compress the contact spring (6) by
use of the spring compressor.

2. Remove spring and spring guide (1).
3. Raise the contact finger to clear toe

primary contact stop plate (8) and Wt

Contact Arm Assembly (7, 20, 22, Figure
21).

Remove connection bar (21).

Disassemble hinge pin (24), cup bear^

toe finger out of contoct support (7).

and spacers used in assemblies.

To replace toe Stationary Primary Contacts:

1. Apply a thin coating of D50H47 gre^e
oS the hinged edge of the finger CS) then
place it on toe contact support (7) so

tween toe bushi^ and contact arms
(both sides) are in place.

3. Turn nut (2) in clockwise torection to
compress contact spring (Figure ZZB;.

5. Reassemble operating rod pin andcon

Hold spring firmly in yoke on spring

Place washer (not shown) on gmde on

top of sprii^, place top of pide into

hole in spring retainer (4) and the
round end of spring guide in cutout in

primary finger (Figure 22C).

5. Hold spring assembly, firmly in place
and remove spring compressor.

D. Movable Primary Contacts (20), Figure 21.
To replace toe movable primary con

tacts on a 1200 ampere breaker proceed as
follows:

1. Disassemble nuts from assembly bolts
(10) and remove the movable primarj'
contacts (20).

Reassemble in reverse order.

To replace toe movable primary con
tacts on a 2000 ampere breaker it is first

necessary to disassemble toe movable arc

ing contacts, then proceed as follows;
1. Disassemble operating rod pin, first
notii^ quantity and location of washers
in toe assembly.

When reassembling, first insert piston
tube assembly into toe booster cylinder
and reassemble the cupbearing, malto^
sure toe silvered contact washers be

2. Open spring compressor (3) ^d as
semble spring guide, sprir^ andspring
compressor (Figure 22A).

The contact arm assemblyinclu^g toe

piston assembly (28), Figure 10 can
now be removed.

that it is retained by stop plate (8).

slipping out of toe compressor.

(23), and operating rod pin noting

quantity and location of any washers

Remove one contact finger at a time.

compressor to prevent sprii^ from

assembly away from each other so ascessible and movable primary contacts
(20) can be removed.

nection bar (21).

After disassembly and reassembly of any
contacts, check all contact adjustments as
described under ADJUSTMENTS.

BUSHINGS

IMPORTANT: DO NOT REMOVE ALL SEX
BUSHINGS AT ONCE. The bushings have been

carefully aligned with toe breaker fram^ during
assembly at toe factory, and it is
this alignment be maintained to insure interch^geability of the breakers in toe metal-clad
"
is, therefore, recommended that toe bushings be

removed and reassembled one at a time. Also,
tance from that particular bushmg to adjacent

before removing any one hushi^, measure toe to bushings in both directions, so that it may be
reinstalled in toe same location.

However, it is possible to remove ^d re
assemble three bushings s^^oae time. If Itos is
preferred, alignment of toe Mslungs may be
accomplished by placing the breaker in a deenergized spare metal-clad umt before J^Shtemr^
the bushing mounting bolts. This must be
before toe interrupters are remstalled.

To replace the bushing, proceed as follows:
Upper Bushing

1. Open toe breaker and remove toe top

Magne Blast Circuit Breaker GEI-88771

'i •

Figure 22A (8034466)

Figure 22B (8034465)

Figure 220 (8034469)

Figure 22D (8034468)

Figure 22. Method of Installing Primary Contact
Springs Using a Spring Compressor

^ring Guide

Compressor Nut
7.
Spring Compressor 8.
Spring Retainer
9.
Assembly Bolts

Spring
Contact Support
Stop Plate

Stationary Primary
Fineer

GEI-88771 Magne Blast Circuit Breaker
INTERLOCK SWITCH

cover, box barrier,

and interrupters as

already described.

Remove the vertical barriers (5 and 13),
Figure 15.

Remove the four bolts at the mounting

flange of the top bushing being removed
and move the bushii^ assembly toward the

front of the breaker.

under ADJUSTMENTS.

LATCH CHECKING SWITCH

To remove the latch checking switch (8), Figure

13, (when furnished), remove the two mounting

NOTE: Shims may be found between toe
breaker mounting plate and toe bushing

moxmting flange on some, or all bolts.

screws and disconnect toe lead wires. Reassemble
in toe reverse order and check toe switch adjust
ments as ejcplained under ADJUSTMENTS.

These shims are for squaring up toe bushing
and may be required when new bushings are

MOTOR, RELAY AND LIGHT SWITCHES

assembled.

To remove toe interlock switch (5), Figure 13,
remove toe two mounting screws and disconnect
toe lead wires. Reassemble in toe reverse order
and check toe switch adjustments as explained

Referring to Figure 22, disassemble toe

primary contact springs (6) as previously
described.

Two or three switches (13) Figure 4, are
mounted in tandem as required by the application.

Remove toe opening spring per instructions
below.

Disassemble toe spring retainer (4) by
removing moimting bolts (5).

Referring to Figure 21, disassemble toe

Remove (2) mounting bolts (11 & !%) from

contact support (5) and interrupter mounting

Remove the (2) mounting screws of toe

Reassemble in toe reverse order". " The

lower switch.

bracket (11) removing two bolts (1).
7.

interrupter mounting bracket (11) is not
symmetrical and must be assembled cor
rectly to orient the interrupter properly
on toe breaker. The longest projection of
toe bracket should be toward the front end
of toe bushing.

Lower Bushing

switch bracket (12).

Remove toe (2) mounting screws of toe
center switch.

Remove the (2) mounting screws of toe upper
switch.

Disconnect toe lead wires of switch to be
replaced.

Open toe breaker and remove toe top cover,
box barrier, and interrupters as already

Reassemble in toe reverse order and check

switch adjustment as explained under AD
JUSTMENTS.

described.

2.
3.
4.

Remove toe vertical barriers (5 and 13)

Figure 15.

Remove manual trip lever (3) and if fur

Disengage trip latch spring (9).

Remove three (3) cotter pins from trip shaft.

Remove toe connection bar (21),

21, cup bearing (23), and hinge pin (24).
Remove the four bolts at toe mounting

flange of toe lower bushing being removed,

and move the bushing assembly toward
toe front of toe breaker. (See note imder

rear bushings concerning use of shims).

TRIP SHAFT AND LATCH (See Figure 9)

When reassembling, first mount toe bushing
and assemble toe cup bearing (23), contact
arm (22), and replace pin (24) beii^ sure
toe silvered contact washers between the

contact surfaces at toe hinge point of toe
contact blade and bushing should have a thin

Check all contact adjustments as outlined

Place a block between toe trip latch (11)

and toe right side of toe mech^sm frame.
Drive toe trip shaft to toe right imtil toe

latch is free of the key, then remove toe key.

coating of D50H47 grease.
under ADJUSTMENTS.

Remove trip arm screw (14) and trip latch
set screw (10).

bushing and contact arms are in place. The

nished, toe latch checking switch qperating arm (6) from toe trip shaft.

Check for and remove any burrs raised

around toe keyway on the shaft to avoid
damaging toe trip shaft bearings.

Shaft, latch, etc., may now be removed by
driving it to toe right through toe notch

Magne Blast Circuit Breaker GEI-88771

in the angle of the lower frame. Note
quantity and location of washers used as
spacers in the assembly.

Reassemble parts in reverse order. Be sure
trip latch is aligned in center of trip latch
roller and that the latch spring is properly

3. Remove prop reset spring (7) Figure 9.

installed.

4. Remove 2 set screws from cam (16),

Figure 4 and remove cam from the main
shaft.

Check latch adjustment as de

scribed under ADJUSTMENTS.

F^re 8, and move cam to the right on

the shaft as far as it will go. Slide the
shaft to the left until key is fully exposed.
Remove key and check shaft for burrs.

TRIP LATCH ROLLER BEARING

Remove (2) cotter pins at ends of trip latch
roller shaft (8) Fi^re 14.

Remove shaft out left side of frame.

Partially remove shaft out right side of

Reassemble in reverse order usingthe cor

frame until latch roller (6) is free.

7. Rotate the mechanism through a closing

Be sure latch roller

operation using the manual charging wrench.
Check the location of the cam follower

(6), Figure 8, on the cam (16) If necessary,

CLOSING LATCH

move the cam to correct the ^ignment.

Remove cotter pins at both ends of closing
latch shaft (17) Figure 4.

Complete the closing operation and check the

location of the prop pin (13) ontheprop (14).
It should be approximately centered,

Remove spring and paddle (18).

Remove set screws from latch (14).

Move shaft (17) to right (away fromframe) by

TRIP COIL

tapping lightly on the inside end of shaft.

To replace the potential trip coil (13), Figure 9,
proceed as follows;

Rotate shaft and continue tapping until shaft

With the breaker in the open position, remove

Remove trip coil support (12) and spacers.

Cut wires at the butt connectors and remove

is free. Shaft will push outside needle bear
ing from housing.

rect number of washers and spacers to

properly locate the parts.

Reassemble in reverse order with proper
spacing of washers.
rotates freely.

Remove 2 set screws from switch cam (9)

Reassemble in reverse order puttingbearing

the two mounting bolts (16).

into frame last. Use a small piece of tubing

or pipe when inserting bearing to assure
proper alignment.

coil.

Check closing latch adjustments as de
scribed under ADJUSTMENTS.

bolting support (12).

MOTOR

To remove motor (11) Figure 3, first

5. Adjust coil location to allow approximately
1/4" of armature travel before latch starts

remove the cotter pin from the rear end

of the treadle link (6), Figure 6.

Remove four mounting bolts from motor
(not shown).

Remove motor leads from the terminal
board.

to move.

Rotate

link up to clear motor.

Reassemble the motor in the reverse order
and re-align it properly as describedimder
DRIVING PAWL ADJUSTMENTS.

Butt connect wires and check operation of
solenoid electrically and mechanically.

SPRING RELEASE COIL

To remove the spring release coil (22) Figure
4, proceed as follows:

1. Bl(^k the closing springs as described
in INSTALLATION.

Remove the right hand closing spring as
described in CLOSING SPRINGS below.

CAM

When replacing the coil be sure to assemble
the correct fiber spacers at the ends before

Remove 2 set screws from ratchet wheel

3. Remove two mounting bolts, coil support
(23), and spacers.

(7) Figure 5 and remove wheel from main

shaft (6).

Cut wires at the butt connectors and re
move coil.

GEI-88771 Magne Blast Circuit Breaker

5. Replace the coil and the correct number

of fiber spacers before bolting support.

6. Butt connect wires and check that toe
armature is not binding.

Check coil for

4. Remove cotter pin and washerfrom spr^
guide pin and remove closing spring (11)

and upper spring guide (8) as a umt.

electrical operation.

Either discharge toe opening springs by

pushii^ toe manual trip lever or block
the openir^ springs with a suitable blocking
device.

CLOSING SPRINGS

The closing springs (10) Figure 3, can be
removed as follows:

Charge toe springs with toe manu^ charg
ing wrench and apply toe special short
blocking pins (13) supplied in toe tool
kit.

OPENING SPRINGS

To remove toe opening springs (5) Figure 5,

proceed as follows:

Charge and block the closing springs as

described under INSTALLATION.

Insert pin so that it is centered
2.

in toe spring support.

2. Discharge springs by pushing manual close

Push manual trip lever (1) Figure 2, to
be sure toe opening sprii^s are fully
discharged.

button (6) Figure 2.

Rotate cam shaft (6) Figure 5, by using

Remove rear pin (2) Figure 5, and front

pin (9).

the manual chargii^ wrench until toe g^

between toe spring (11) and toe beari^
block (8) is a maximum (approximately

After reassembling springs check toe open

gap at toe primary contacts as described

under PRIMARY CONTACT GAP.

3").

RENEWAL PARTS
It is recommended that sufficient renewal parts
be carried in stock to enable toe prompt replace
ment of any worn, broken, or damaged parts. A
stock of such parts minimize service interruptions
caused by breakdowns, and saves time andexpense.
When continuous operation is a primary consider

ation, more renewal parts should be carried, toe

ORDERING INSTRUCTIONS

of both toe breaker and toe mechanism.

amount depending upon toe severity of toe service
and toe time required to secure replacements.

Renewal parts which are furnished may not be
identical to the original parts since improvements
are made from time to time. The parts which are
The listed terms "Right" and "Left"

apply when facing toe front or panel end of toe

Specify toe quantity, catalog number (if
listed), reference number (if listed), and

description of each part ordered, and this

bulletin number.

furnished, however, will be interchangeable.
NOTE:

Always specify toe complete nameplate data

Standard hardware, such as screws, bolts,

nuts, washers, etc., are not listed and
should purchased loc^ly.

For prices, refer to toe nearest office of
toe General Electric Company.

breaker.

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In toe following tabulations are listed those parts of toe brewer and
operating mechanism which are usually recommended for stockfor
normal maintenance. Other parts can be obtained by contacting toe
nearest office of toe General Electric Company.

Magne Blast Circuit Breaker GEI-88771

RECOMMENDED RENEWAL PARTS FOR

TYPE ML-13A STORED ENERGY MECHANISM

USED FOR AMH-4.76-250-0D & ID, 1200 & 2000 AMPERE
Fig.
No.

Ref.
No.

No.

Description

Req'd.

Spring Charging Motor - **

48 V-DC

110 & 125 V-DC & 115 V-AC, 60 Hz
220 & 250 V-DC & 230 V-AC, 60 Hz

115 V-AC, 60 Hz
230 V-AC, 60 Hz

i
13

110 & 125 V-DC

115 V-AC, 60 Hz

230 V-AC, 60 Hz
24 V-DC
48 V-DC

110 & 125 V-DC

115 V-AC, 60 Hz
230 V-AC, 60 Hz
48 V-DC

13
13
4
18
7

4
9
*

5
1
1
1
1
1
2

0108B1978G001
0137A7575P005

0137A7575P002

006174582G001
006174582G015
006174582G002
006174582G013
00 6174582G032
006275070G001
006275070G002

Spring Release Coil - *»
220 V-DC
250 V-DC

4
9

0137A7575P004
0137A7575P001

Potential Trip Coil - **

220 V-DC
250 V-DC

0105C9393P001
0105C9393P002
0105C9393P003

Relay - **, #

48 V-DC
110 & 125 V-DC
220 & 250 V-DC

Catalog No.

Switch, Normally Open
Switch, Normally Closed
Auxiliary Switch

Closing Latch Spring
Prop Spring

Driving Pawl Spring
Latching Pawl Spring

006174582G001
006174582G015
006174582G002
006174582G010
006174582G014
006275070G002

0456A0866P005
0456A0866P006
0137A9192G003
0161A4231P001
0137A9252P001
0161A4241P001
0161A5909P001

Not Illustrated

Refer to breaker nameplate or summary for proper voltage rating.

Quantity Two (2) relays required on special control circuits. Check

breaker and connection diagram.

GEI-88771 Magne Blast Circuit Breaker

RECOMMENDED RENEWAL PARTS FOR MAGNEBLAST BREAKERS
TYPE AMH-4.76-250-0D & -ID, 1200 & 2000 AMPERES

Fig.
No.
10

10
10
10
10

21
21
21
21
21
21
21

21
17
17
18
18
18
18
19
*

Ampere
No. Rating
Ref

13
13
21
28
28
2
4

4
7
16
17
19

20
11
11
7
7

8
12
3

1200
2000
ALL
1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

Catalog No. For Type AMH-4.76-250
•OD

0195A4091G001

0195A4091G002
0137B7902G001
0213X0343G043
0213X0343G044
0236C0790G009
0236C0791G001
0236C0791G004
0802B0742G001

0195A4091G002
0137B7902G001
0213X0343G090
0213X0343G091
0236C0790G009
0236C0791G001
0236C0791G004
0108B5506G001

0414A0116P004
0121A5964P001

0121A5964P001
0114C5382P002
0114C5382P004

0114C5382P002

000421711P001
000407193P001
0108B1965G001

000421711P001
000407193P001
0195A7377G001

0114C5382P004

0108B1965G002

0195A7377G002

O161A59O6PO0L

0161A5906P001
0114C5381P010
0414A0116P002
0836C0197P014
0195A7388G002

0114C5381P001
0114C5381P004
0836C0197P014

ALL

* Not Illustrated

• ID

No.

Req"d.
6
6
3
3

3
3
3
3
3
3

18
18
6
6

6
3
3
6

Description

Primary Disconnect Fingers
Primary Disconnect Fingers
Operating Rod Assembly
Tube & Piston Assembly
Tube & Piston Assembly

Arcing Contact Assembly
Flexible Connector (Left)
Flexible Connector (Right)
Movable Arcing Contact
Insulatix^ Plate

Primary Contact F^er Spring
Primary Contact Finger
Movable Primary Contact
Insulating Cap

Threaded Washer (For Insul. Cap)
Throat Insulation (Left)

Throat Insulation (Right)
Front Runner Shield
Front Insulation

6
3
6

Insulating Plate

Throat Barrier Assembly

Rear Rimner Insulation

Magne Blast Circuit Breaker GEI-88771

(

GEI-88771 Magne Blast Circuit Breaker

GCZ-2»O0t^

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6ENEIAI ElEa«IC COMPANY, PHILADELPHIA, PA.

GEI.23903C

INSTRUCTIO NS

POWER
CIRCUIT BREAKERS
Si il

Magne-blast Breaker
Types AM-5-50-4
and AM-5-50-5
With MS-9 or MS-9-1
Mechanism

GENERALS ELECTRIC

CONTENTS

INTRODUCTION

.............

.......................
.......................................

RECEIVING, HANDLING AND STORAGE

DESCRIPTION

.. .

INSTALLATION ••••
PRECAUTIONS
INSPECTION ••

OPERATION ••••••••••••
PRINCIPLES OF OPERATION

AD1tJSTMENTS ••••••
Primary Contacts
Arcing Contacts ••
Contact Gap

MAINTENANCE
PERIODIC INSPECTION
LUBRICATION • ••••• •
REPLACEMENT OF PARTS
RENEWAL PARTS

....................................

PAGE

�

..I

3
4
4
4
5

6
6
6
6
7
7
7
7
9

�

MAGNE-BLAST AIR CIRCUIT BREAKER

TYPE AM-5-50-4 AND AM-5-50-5
WITH MS-9 MECHANISM
INTRODUCTION
The Magne'blast Air Circuit Breaker shown

ers have an interrupting capacity of 50,000 KVA on

on the cover is a triple pole single throw breaker

with integral operating mechanism and is arranged

a duty cycle basis consisting of two closing-opening
operations with a time interval of 15 seconds be

for application in Vertical Lift Metal-Clad Switch-

tween them.

gear.

The Breaker-Mechanism combinations is de

The Am-5-50-4 Breaker is available in 1200

ampere ciirrent rating only, the AM-5-50-5 break
er is available in 600 an^re current rating only.
These Inreakers are designed for application at a
TnaTimmti circuit voltage of 5000 volts. Within the

piAlished interrupting current range, these break

signed only for electrical closing and the Mainten
ance Closing Lever is supplied only for use in mak
ing adjustments. NEVER ATTEMPT MANUAL
CLOSING WITH THE BREAKER IN SERVICE, for

under such conditions, sufficient closing force and
speed cannot be applied.

RECEIVING, HANDLING AND STORAGE
cluded in the crate. Care should be taken to make

RECEIVING

certain tha^ these parts are not overlooked.

Each Circuit Breaker is carefully inspected and
then is packed1^ workmen e:q>erienced in the proper
handling of electrical swttchgear.
Immediately on receipt of a Circuit Breaker, an
examination should be made for any damage sus

tained during shipment. H injury or rou^ handling
is evident, a damage claim should be filed at once
with the Transportation Company, and the nearest
General Electric Company's Sales Office should be
notified promptly.

After the Breaker has been removed from the

crating, the brace and steel hooks, holding the Box
Barrier in position, should be removed and discard
ed.
STORAGE

It is advisable that the Breaker be set up im

mediately, but if it must be stored, it should be kept
in a clean dry place, free from corrosive gases or
fumes. During construction work, particular care
should be taken to protect this apparatus from

HANDLING

The breaker should be removed from the crat

ing with sufficient care so that no damage will re-

^t from rough handling, tt frequently happensthat

'loose parts" associated with the apparatus are in

moisture and cement dust as this combination has

very corrosive effects onmany parts. Allmachined

parts except those on the contacts should be coated
with heavy oil or grease to prevent rusting.

DESCRIPTION
The Magne-blast Air Circuit Breakers, listed
on the cover with MS-9 or Ii^9-1 Mechanism may
be seen in a cut-away view on Fig. 5.

R is composed of a solenoid operated mechan
ism boltedtoafabricatedframe; sixherkolite bush

ings with ball ends for good contact and easy install
ation in Vertical Lift Metal-Clad Switchgear; three

operating rods of insulating material; three movable

contact arms with primary and arcing contacts
three stationary contact blocks and rear arc runner
assemblies, containing the blow-out coils which are
motmted on the loack bushings; three front arc run
ners mounted on the arc chutes; three molded plas

tic "boosters" which supply air for aiding in the in

terruption of low currents; and three arc chutes of
arc-resisting and insulating compound which segre
gate the three interrupting units.

INSTALLATION
Outline, wiring and all (Aher drawings relating
to dimensions electrical connections and control

shouldbe on hand sothatpoints in question are read

ily settled as they arise. Before any installation
work is done, consult these drawings and the In
struction Book for the "Metal-Clad Switchgear".

GEI-2390SC

Type AM Magne-blast Air Circuit Breaker

The complete Breaker Mechanism unit has al-

damage was done during installation. Check

ready been assembled, adjusted, inspected, and test -

all terminals, screws, and connecticns and

ed at the factory in accordance with the detailed ad

test the circuits for possible short circuits
or grounds.

justments listed under the section OPERATION. R
is possible, however, that unusuaUy rough hancUing
or transportation may have caused some loosening
or disturbance of the apparatus to warrant a rechecking and in some cases, readjustment.

3. Engage the pin througdi the end cfthe main
tenance closing lever in the notched bracket

under the mechanism (see Fig. 5) and push
down on the end of the lever closing the

Before proceeding, the following precautions

breaker. With a screw driver (CAUnON:

should be noted:

Keen the fingers clear of the linkage as aecidental tripping or fast movement could

cause severe inlurv) rrtate the orgp from
under the closing roller pin with the main
tenance operating handle pushed all the way

PRECAUTIONS
Make certain that all Control Circuits have been
de-energized.

down and then raise the handle to open the
breaker. Operate in this cycle of slow close
and slow open operation several times mak

Make certain that the Primary Breaker Circuits
are open and effectively grounded.

ing certainthat all parts are working freely.

4. Check the operating voltage for both the
closing coil and trip coil to determine, if
with line drop it is irtthin the limits speci

Never work oneither the breaker or mechanism

while in the closed position unless the Prop anlTrip

Latch have been '^red or blocked to prevent ac
cidental tripping.

fied on the nameplate. Inthe case at a rec

tifier operated mechanism, the D.C. voltage

INSPECTION

across the coil terminals with full closing
coilcurrentflowingshouldbe 100 volts. Ad

1. Check all nuts, bolts, screws, and cotter
pins to make certain that they are proper

justment is possible fay means of the ti^ re

sistor in the rectifier A.C. line. For detailed

ly tightened.

description of this adjustment refer to histruction Book on Copper Oxide Rectifiers

2. Inspect all wiring and make certain that no

for Circuit Breaker Closing Service.

OPERATION
After the breaker has been closed and opened
slowly with the maintenance closing lever and the
voltage snpply for both the closing and the trip coils
checked as described under Installation, check the
following items;

7. The plunger clearance.

All these dimensions are given under Adjust
ments.

The MS-9 solenoid mechanism is trip free and

1. The wipe of the primary contact.

will operate satisfactorily overthestandud ranges

2. The gap betweenthe primary contact fingers

for closing andtripping voltages as discussed below.

from either an Alternating or Direct Current source.

and the movable primary contact block with
the arcing contacts just touching.
The gap between the primary contacts with
the breaker in the open position.

For electrical operatiom^control power maybe
In the case of Alternating Current, it is necessary

to use a Copper-Oxide Rectifier tosupply the Direct

Current required by the closing coil.

4. The latch wipe.
5. The prop clearance.

Gyrating ranges are given on the mechanism

nameplate. Ordinarily, standard ranges apply and

6. The latch clearance.

are as follows.

STANDARD CLOSING AND TRIPPING VOLTAGE RANGE
Nominal
Voltaee

Closing
Ranee

Tripping
Ranee

125 V. DC.

90-130 V. DC.

70-140 V. DC.

250 v. DC.

180-260 V. DC.

140-280 v. DC.

220 V. AC.

180-240 V. AC.

Type AM Magne-blast Air Circuit Breaker GEI-23903C

PRINCIPLES OFOPERATION

the end of their travel, the prop rotates into position

The Magne -blast Circuit Breaker utilizes mag
netic forces produced by the load current through
the blow-out coils to interrupt the arc. These mag

mechanism is held in the closed position. The sole
noid coil is de-energized by a relay which is actu

under each end of the pin throu^ the roller and the

netic forces together with an air stream from the

"boosters" drives the arc from the contacts out along
the divergingarc runners into the "interleaving' arc
chutes. The tapered fins that project alternately
from the two opposite inner surfaces of the chute

deflect the arc into a gradually deepening serpen

tine path. This lengthening and consequent cooling
action rapidly increases the resistance of the arc

to cause interruption. Hot exhaust gases are cooled
while passing through the muffler at the end of the
arc chute. Easily removable box barriers encase

ated by the cut-off switch at the ena of the armature

stroke, and the armature Is returned )jj gravity to
its original position.

When the trip coil is energized, the plunger
forces the latch off the roller causing the linlaige to
collapse which allows the opening spring to rotate
the main crank and open the contacts. During the
opening stroke, auxiliary switch contacts open to in
terrupt the trip coil circuit. After the breaker is

open, the mechanism linkage returns to its normal
position, and a spring resets the trip latch.

each phase separately, segregating the interrupting
units and providing in^ation between phases ana
from each phase to the grounded frame.

breaker is closing, the trip plunger forces the latch

For the following closing, tripping and trip-free

completes its closing stroke, however, and the coil
is de-energized as in a normal closing operation.

In case the trip coil is energized vhile the
off the trip roller allowing the mechanism linkage
to collapse and the breaker to reopen. The armature

operations Fig. 5 may be consulted.

When the solenoid coil is energized, the arma
ture is driven upwards and the plunger rod threaded
into the armature raises the roller carried by the
set of links fastened to the operating crank. This
action rotates the crankand closes the breaker con

tacts. After the armature and linkage have reached

When the breaker is tripped under load or short
circuit conditions, the opening springs act to swing
the contact arms downward, parting first the prim
ary contacts, and then the arcing contacts. The arc
is then transferred to the arc runners and, as des

cribed before, into the arc chutes where it is inter
rupted.

CAP SCREW
ALLEN WRENCH

ARCING C0N1ACT
SPRINGS

LOCKING WIRE

PIVOT SPRING
LOCK NUT-

PRIMARY CONTACT
FINGER

STOP BOLTSPRING CUP

ARCING FINGER

ARCIN6FIN6I
PIVOT

Fig. I

Contact Assembly

GEI-23e03C Type AM Magne'blast Air Circuit Breaker

ADJUSTMENTS
Adjustments described herein should be re
ferred to not only during placement of breakers in
service but also during periodic inspection of the
breakers, and should be follovred udtenever it be
comes necessary to repair or replace parts that
have become worn or defective in service.

pin to positively lockthe stop nut, a new hole should
be drilled. After the cotter pin has been replaced,
the breiiker shouldbe closed and tripped and the ad

justment checked. Note: A change in this adjust
ment may require a change in the adjustment of the
plimger rod in the mechanism as described later.

Instructions for the replacement of parts will
be found under the later heading of Maintenance.

CLOSING

ROLLER

PRIMART CONTACTS (Figs. 1 and 5)
With the breaker in the closed position the top

face M the primary contact fingers should be hori
zontal. This can be adjusted by means of the oper

•TRIP

ating rod adjusting screw. To adjust, remove the

'pin mstening the adjusting screw to the mechanism
crank and push the contact blade far enough closed
so the adjusting screw can be turned. To Increase
the primary contact travel, turn the adjusting screw
in the direction to lengthen the rod, and to decrease

the primary contact travel, turn the screwtoshort
en the rod (2 turn gives approximately 1/32"change
in contact travel). Reconnect the operating rod to
the crank, and close the breaker manually to check
the adjustment.

After the above adjustment has been made, the
travel cf the contact surface of the primary contact

finger should be measured on a manual closing oper
ation. This travel or wipe should be 1/9' or over.
If enou^ material has been removed from the prim

ary contacts, to reduce this travel below 3/32", the
primary contacts should be replaced.

ARCING CONTACTS (Fig. 1)
Close the breaker until the arcing contacts just

touch. The gap at the primary contacts should be
7/32" to 9/32". To adjust, the following procedure
should be followed: -

LATCH

TRIP ROLLER
PROR

PLUNGER
CO

K
CO

Fig. 2

Hechanlsn Linkage Closed Position

Latch Wine fFig. 2)

The wipe of the latch on the trip roller should
be from l/8"to 1/4". This can be determined easily
by putting a film of grease on the latch, closiiw the

breaker part way, and tripping. To adjust, add or
remove washers under the head of the ^op bolt lo

cated near the top of the latch on the trip coil frame.
Prop Clearance (Fig. 3)

With the breaker closed as far as possible with

the manual handle, the clearance of the pin tlurough

the closing roller over the prop should be 1/32" to
3/32". This can be adjusted by dropping the closing
coil and screwing the plunger rod into or out of the

(a) Remove the arc chute.
(b) Loosen the lock nut on the arcing contact
stop bolt.
(c) With Allen wrench, turn the stop bolt until
the arcing contacts just touch when the gap

armature. Note:

Two set screws are used to lock

the plunger rod in posltlmi in the armature. If the
rod adjustment Is changed the rod must be spotted
in the correct position and the set screws replaced.

at the primary contacts is 7/32" to 9/32*'.

OPENING SPRING

(d) Lock the stop bolt in position with the lock-

nut, and close the breaker manually to check

the adjustment.
(e) Replace the arc chute.
TRIP LATCH

CONTACT GAP (Figs. 1 and 5)
With the breaker tripped from the closed posi
tion, the minimum distance from the primary con
tact fingers to the contact surface of the contact blade
should oe 4". At the same time, the clearance be
tween the underside of the contact blade and the top

TRIP ROLLER
PROP

40 i

CLOSING
PLUNGER

of the booster cylinder should be at least 3/8" to

ROLLER

3/4". To adjust for these conditions, remove the
cotter pin from the mechanism stop nut and turn the
stop nut to Increase or decrease the contact gap. If
the old cotter pin hole cannot be used for the cotter

Fig. 3

Mechanism Linkage Open Position

<9>
sr
u>
I

Type AM Magne-blast Air Circuit Breaker GEI-23903C
Latch Clearance (Fig. 3)

The clearance between the trip latch and roller
with the breaker open should be approximately 1/32".
This can be adjusted
means of the stop bolt in the
front of the mechanism frame near the bottom. The

should be at least 1/8" clearance between the plung
er and closing roller. To increase this clearance,
the brackets to catch the armature in the open po
sition should be lowered by placing a shim between
them and the coil bottom plate.

lock nut should be fastened securely if any a(^ust~
ment has been made.

After the foregoing items have been checked and
any adjustments that may have been required are

Plunger Clearance

With the breaker in the open pos it ion, there

completed, the breaker may be placed in service.

MAINTENANCE
Dependable seiMce and safety of power distri
bution equipment is based onthe unfaiHng perform

ance of the circuit breaker.
To maintain such service, it is recommended
that a definite schedule be setup and adhered to for

any way and should be disregarded. If the

chute has had any mechanical injury due to
dropping or accidental striking which has
resulted in actual breaking off of fins, re
placement of the chute is necessary.

the purpose cf properly lubricating the wearing
parts. A dependable and observing attendant can te
e:qiected to forestall mishaps by reporting loosened
nuts, scored surfaces, and other evidences of possi
ble trouble.

In addition, but at less frequent intervals peri

odic inspection should be made at which time the ap
paratus should be given such servicing as may te
found desirable or necessary. Di case of highly
repetitive operation it is recommended that the first

Periodic Inspection be made after not more than 500

operations to determine vdiether there has been any
loosening up of parts. The interval between later

Periodic Inspections should depend on operating conditions and should be determined by experience.

PERIODIC INSPECTION
At this time a thorough inspection should be
made of all parts of the breaker and mechanism.
Contacts

After re movingthe box barrier, the contacts on
the twooutside phases can readily be inspected. The
contacts on the center phase can be seen with the
aid of a mirror and flashlight. If the contacts are

in good condition, there is no need of removing the

arc chute. If, however, the surface of the contacts

needs smoothing up with a fine file or sand paper,

the arc chutes can be removed as described under
the heading REPLACEMENT OF PARTS.
Arc Chute

If the arc chutes are removed for contact main
tenance, and are for any reason disassembled for in
spection, the following points should be nrted:
1. Scale formed over the surface of the chute

must not be removed but loose particles
collected in the muffler should be blown out.

2. Cracks vdiich have formed in the fins of the

arc chute are to be expectedin ceramic ma
terials of this type when subjected to the se
vere heat of an arc. These cracks do not in

terfere with the operation of the device in

Insulation Parts

The insulation parts on the breaker should be
kept clean and dry. Smoke or dust collected between

inspection periods should be wiped off, and if damp
ness is apparent, heaters should be installed to in
sure dryness.
Bushings

The surface of the bushings should be smooth
and unscratched. If the insulation surface should

become damaged, it should be well cleaned and then
re-touched with either 1170 clear varnish or 1202

(clear) or 1210 (brown) glyptal. Allow to dry smooth
and hard.
Mechanism

Careful inspection should be made to check for
loose nuts or bolts and broken cotter pins. The latch
surface should be inspected for wear and the sur

faces of the rollers should be inspectedfor chipping
or other evidences of damage. Lubrication should
be done in accordance with the instructions under the

heading LUBRICATION.

LUBRICATION
During assembly at the factory, all wearing
parts, bearing surfaces and all machined surfaces
on both the breaker and mechanism have been coat

ed with a film of medium soft lubricating and rustresisting greases. At regular maintenance periods,
apply a few drops of machine oil SAE-2p or 30 to
bearings. Ground surfaces such as cams*and roll
ers should be wiped clean and a thin coat of General
Electric Lubricant D50H15 applied.

When the breaker is given a general overhaul
or is disassembled, or when operation becomes

sluggish, the following procedure should be follow
ed: • On bearings, the pins should be removed and
all old oxidized grease cleaned off of parts by soak
ing in kerosene or similar cleaner. Do not usecar-

bon-tetra-chloride. If the grease in the bearings
has become badly oxidized, it may be necessary to
use alcohol (the type used for thinning shellac) to re
move it. Ordinarily, by swishing the bearing around

GEI-23903C

Type AM Magne-blast Air Circuit Breaker

and removing solid particles with a stiff brush, the
bearings can be satisfactorily cleaned. After the
' bearings have been thoroughly cleaned, spin them
in clean, light machine oil untU the cleaner or sol
vent is entirely removed. Allow this oil to drain off
and then repack immediately with General Electric
Lubricant D50H15 being certain that all metal parts
are greased.
General Electric LubricantDSOHlS is available

only in cartons containing twelve collapsible tubes

of grease. This is a total of three pounds of grease
to the carton. It is so packaged to insure cleanli
ness and to prevent oxidation.

REPLACEMENT OF PARTS
Before maintenance or replacement of contacts,
the arc chutes must be removed.

Arc Chute Removal (Fig. 5)

<*>
to

To remove the arc chutes, first loosen the two
arc chute supporting bolts (one on each side of the
chute) and remove the arc runner connection bolt.
The arc chute is then free to be pulled away from

the mechanism.

Primary Contacts (Fig. 5)

The primary contacts are designed to carry the

Fig. 4

Contact Blade Hinge

Arcing Contacts

normal load current with a minimum amount of heat

ing and are provided with an inlaid block of silver
to minimize the effects of wear. The stationary

contacts consist of 4 fingers for the 12(ra
ampere breaker and are mounted along with the as

sociated springs on the support casting carried ^

the rear bushing. The fingers may be replaced aft
er removingthe locking wire through the pivot end.
The movable primary contact is carried on the
blade hinged at the front bushing. The arc chute
must be removed (see section Arc Chute Removal)
and the following steps should be followed for re
placement of the contact blade: -

The movable arcing contact is bolted on the
front of the contact block on the primary contact
blade and is more convenient to replace with the
contact blade removed.

The stationary arcing contact (see Fig. 1) is
carried by the bracket fastened to the lower side of
the rear bushing. To remove, take out the two Al
len head cap screws from the top. To replace, the
following steps should be followed:

(a) Remove lock nut and stop bolt.
(b) Place arcing finger on pivot pin.

(a) Removetheboltfasteningthe arc chute sup
porting bracket to the lower end of the front
bushing, and remove the bracket.

(b) Disconnect the puffer tube and operating rod

(d) Place pivot spring guide block in position

form the contact blade.

(d) Slip the contact blade off the end of the bush
ing and withdraw.

Reassemble the replacement parts making cer
tain that all cotter pins are replaced. If a new hinge
bolt has been used, or if it seems desirable for any
other reason, the pressure at the hinge joint should
be checked by measuring with a spring balance the
force required to swing the contact arm. For both

the 600 and 1200 ampere breakers, this force should
be between 40 and 60 pound-inches.

finger.
on the underside

the top of the bracket.

(e) Insert spring through the top of the bracket,
spring block and into the spring cup,

(f) Place the assembly on theimderside of the
bushing, and engage the cap screws one turn
in the spring guide block.

(g) Insert the arcing contact springs and guide.

(h) Ti^tenthe cap screws, and reassemble the
stop bolt and lock nut.

The contacts should be adjusted as described
previously under the section ADJUSTMENTS.

Type AM Magne-blast Air Circuit Breaker

GEI-23903C

RENEWAL PARTS
It is recommended that suflicient Renewal

Parts be carried In stock to enable the prompt re

placement of any worn, broken or damaged parts.
A stock of such parts minimizes service inter —

ject to wear in ordinary operation and to damage or

breakage due toabnormal conditions are marked as

ruptlons caused by breakdowns, and saves time and

recommended renewal parts.

consideration, more renewal parts should be car
ried, the amount depending upon the severity of the
service and the time required to secure replace

est General Electric Sales Office, specify the quanti
ty required and give the catalog number from the

ments.

Renewal Parts Bulletin.

expense. W'hen continuous operation Is a primary

REAR

A complete list of renewal parts is contained in
Renewal Parts Bulletin GEF-3391. Those parts sub

BUSHINQ-

CONTACT

When ordering renewal parts, address the near

FRONT

6USHIN0

BLAOE"

eCX BARRIER
tCCRINO

SCREW

PRIMARY

PINQCR-

ARC

OPENINS

5PRIN6

RUNNER _

CONNECTION

ARCmS

FINBCR-

ARCINB

OPE RAT IHB

TIP '

BLOWOUT

BEAR

BOLT

-TRIP

ROO

LATCH

COII^

ARC

RUNNER-

.OPERATINO ROO
A0AU9TIHB

PRONT

ARC

RUNNER-

-AIR

POLE

piecE-

TUBE

SCREW

AND

CYLINOER

.ARC OHUTC
BUPPORTINO

BOX

PlITON

BARRIER-

Fig. 5

Typical Hagne-blast Air Circuit Breaker Type AM 5-50 With MS-9 or MS 9-1 Mechanism

BOLT

INSTRUCTIONS

GEM3532D
Su»iii»ccc<

POWER CIRCUIT BREAKERS
MAGNE-BLAST AIR dRCUTT BREAKERS
TYPES AM-5-100 AND AM-5-150

SWITCHeUR DEPARTMEHT

general^ ELECTBIC
PHIIAOELPHU, pa.

CEI>)3S32C

i I

Breaker Fname

FIG. 1 mONE-BUST BREAKER ARRANGED FOR
USE IN At; ffi-6 METAL CUD EQUIPMENT UNIT.

MAGNE-BLAST AIR CIRCUIT BREAKERS
TYPE AM-5-100
AM-5-150

These instructions do not purport to cover
all details or variations in equipnent nor to

provide for every possible contingency to be
met in connection with installation, operation
or maintenance. Should further information
be desired or should particular problems arise

tion by the over center position of the com
pression toggle. The coil is de-energized
by the relay actuated by the cut-off switch.

When the trip coil is energized, the
trip armature is moved upwards rotating the
trip shaft which releases the trip hammer.

which are not covered sufficiently for the pur-

The trip hammer strikes the closing link
forcing it off the roller bearing of the
operating crank allowing the opening springs

chaser's purposes, the matter should be re
ferred to the General Electric Company.

contacts. The stud strikes the release spring
to break the compression toggle allowing the

GEKERAL IHPORHATION

reset the mechanism.

Tbe

HaEne'Bl&sl Air Circuit

urevker

shown in Fig. 1 is a triple pole single throw
breaker with integral operating fflechanisa
and is arranged for application in Vertical
Lift Metal Clad Switobgear.

These breakers are available in 600,
1200, and 2000 ampere current ratings and
are designed for application at a

breaker

resetting springs to raise the armature and

Incase the trip coil is energized while
the breaker is closing, the trip hammer
strikes the closing link forcing It off of

the roller bearing of the operating crank
allowing the breaker to open. The reeehanisai
iimediately resets when the solenoid coll
is de-energized by the control relay.

maximum

Circuit voltage of 6000 volts. Within the
published interrupting current range, the
AM-5-100 Breaker has an interrupting capac

rotate the.crank and open the

When the breaker is tripped under load

short circuit comUtions, the opening

on a duty cycle basis consisting of two clos

springs act to swing the contact arms down
ward, parting first the primary contacts,
then intermediate contacts, and then the
arcing contacts. Magnetic forces of the
Blowout Coils, together with an air stream

ing-opening operations with a time interval

from the "Booster" drives the aro from the

of 15 seconds between them.

contacts out along the diverging Aro Runners
into the "Interleaving" arc chute.
The
tapered fins that project altennat»ly from

ity of 100,000 XVA and the AH-S-150 Breaker

has an interrupting capacity of 150,000 KVA

OPSIATINO CBARACTESUSTZCS

the two opposite inner surfaces cf the chute

The Breaker-Mechanism combination

designed only for electrical closing and
the Maintenance Closing Lever is supplied

only for use in making adiustmeots.

NBVBR

deflect the arc into a gradually deepening
serpentine path. This lengthening and con
sequent cooling action rapidly increases the
electrical resistance of the arc to

cause

cient closing force and speed cannot be ap

interruption. Bet exhaust gases are cooled
while passing through the Muffler at the end
of the arc chute. An easily removable Box

plied.

Barrier encases the interrupting units, pro

The MS-7A solenoid meohaoisn is trip
free and will operate satisfactorily over
the standard ranges for closing and tripping

each phase to the grounded frame.

ATTIiMPT HAlftJAL CLOSINC WITH THE BREAKER IN

SERVICE, for under such conditions

suffi

voltages discussed later under CONTROL.

When the solenoid coil is energized,

closing

link

is pulled down until it

A spring nain-

tains engagement between the closing

link

and roller bearing of the operating crank
which is rotated to close the breaker.

from

CONTROL

For electrical operation, control power

the armature (refer to Fig. 3), carrying the
stopped by the polo piece.

viding insulation between phases and

The

breaker is held in the fully closed posi

may be from either an alternating or direct
current source. In the case of alternating
current, it is necessary to use a uopper
Oxide Rectifier to supply the direct current
required by the closing coil.

Operating ranges are given on the me
chanism

nameplate.

Ordinarily,

rangi s apply and are as follows:

standard

-2-

Nomlnal

Closing

Voltat^a

Riinge

125 V.DC,
250 V.DC.
220 V.AC.

96«130 V.DC.
180-200 V.DC.

180-240 V.AC.

Tripping

hook. It Is possible, however, that unu.ually rough handl ihg or tranapirtatlon m!v

liange

iwve caused some loosening or disturbance of
the apparatus to warrant a reobelking wd tn
some cases, re-adjuslment.
^

70-140 V.DC.
140-280 V.DC.
180-240 V.DC.

ftofore proceeding, the followiot ore-

SHIttJENT

cauttons should be notid.

and
is carefully Inapeoted
h
workmen
experienced
in the
proper handling
end packing
of electrioal

equlpnent. lanediutely upon receipt of »
circuit breaker, an examination should bo
any damage sustained during ship-

oent. If injury or rough handling is eviSfti*
shouldcompany
be filedand
at once
with ^e transportation
the

PaSCADTIOKS

have itil
Never work on a closed breakof* *4*a

nearest General Electric Company'a Sales

co.vtacts

tWPACKING

u P''^"®'*/ contact
(Fig. 3)
^ould V
be horizontal.
This fingers
can bo adjusted

Office should be notified promptly?

f—

It®®''®'" should be removed from the

breaker closed, the too sur-

In PI* ®E®''®^J''«/od adjusting screw shown
tact
fingers shou^*bi 3^" ±1/32"Yiwl^ean

e^Vi"n
so that no
age fill resultJ'^fl'lclent
from roughcare
handling.
It dsmfreed^with
thS'^n"'
"loose parts" assoeiat4
.• ®PP®ratu« are Included in the
that these parts are not overlooked. certain
that^theirna'^*'""

ge«''Sith''tir®" I''® Pftoary block and fln-

♦i,.s

breaker has been removed from

iSe ^

®^®®^ books hold-

f
position
shouldhe»be
removed and d?
discarded.
The red painted
head shipping bolts holding
hv
2
frame
should
be replaced
hy the Thumb Screws
as shown
in Pig.
3.

out blocking to prevent tripping.

adjusting screw which

no Inch-pounds
4»5?®
bUdeswhen
should
have 40in in
to
dO
torque
the blade
ad

?n»

(

position. This can be ®adju8S

tightening Ue blade pressure adjust-

storage

un iMedlately, but If it ausi
*be breaker
be set
Up
be stored
it

®®^®®"
fMm oorroeive gases
or fumes. pJaoeTl-Vee
During constraotlon work, particular care should bo
^ken to protect this apparatus fhojo molstare and oement dust as this combla^ion has
wery corrosive effects on many p^. All
°» «>. cent....

THIP MBCHANISH

««.«•.»check
of the
Mctaniw
closethetheadjustment
breaker part
way trio
and
trtp. Then reset the meohanlso slowlv with

/^W5"sre;"f.ris

IKSTALUTION

other drawings

ioiati fH
thi?

dimensions, electrical oonnec-

«bould be on hand so that
*''® readily settled as

Vith

the breaker closed, adluoi »».-

"^®P,screw so that the trip shfft h>t

1/32 to l/l6" lap on the catch of the trie

,.^5**®
Installation
workInis
done, ^1?
consult
these drawings
and theBtruotlon Book for the "Metal-iJlad Swlteb-

goar" type HI-», GEl-tt25C.

•

h««n *«® complete Breaker unit has already

;pp.r.{;r:c^;'.rsi
.'.i;
plate roises l/S" to 1/4" above the firlnJ

detaffa^ adjustments
a? '®®*®''7 given
^n Bcoordance
withthis
the
detailed
later in

tee upper stop sorew tightly. Now raise
oach armature separately by hand to tha

?®?u

adjusted, inspected and

(

-3-

litRit of their etroke and be sure they will

.V^

each rotate the trip shaft far enough to re
lease the trip hanwier catch. Do not remove
tlie trip shaft *hen making adjustments.

Lap of trip shaft on trip hammer

catch - 1/32" to l/ltf".

Clearance between firing pin and
trip shaft extension, both in low

With the breaker in the open position,
there should be 1/16"'to 1/8" clearance be
tween the trip shaft and the trip hammer.
This adjustment is obtained by turning the

ered position - l/lC" to 1/8".
d.

Clearance between firing pin and
trip shaft extension, both in raised

two set screws on the short arm of the trip

position - 1/8" to 1/4".

hammer in or out as required. The lock nuts
should be tightened after this adjustment is

made.

Clearance between trip hammer and

trip shaft with breaker open - J./18"
to 1/4".

CL0SIK6 HBCRAKISH

Vlth the armature in the fully closed
position, the closing tuggle i4--l'ig. 4)
(27—Pig. 4) should be free to snap over
center 1/8" to 3/16", This can be adjusted
by changing the position of the adjusting
stop (S-Fig. 4) and by changing the number
of shims (18-Fig. 4) between the armature
and pole piece. Vlth the armature in the

ACCESSORIES

For information and instructions psrtaining to aocessories such as rslays, recti
fiers, undervoltage devices, and time de

lay trip colls refer to the instnietlon book
of the device in question. The numbers of

oBon position, the operatl'ng crank (2B-Fig.

instruction books and renewal parts bulletins
will be found on the niuneplate of the devlos.

Plg. 4).

KAINTENAKCB

4) should be against the buffer stop (30-

The buffer stop (32-Plg. 4) should

be adjusted by adding or removing shims to

femit unrsstrainsd motion of closing link
of

These breakers should be inspected every
six months or more often depending upon con
ditions. Tho arc chutes on all ptaasss should

A locking wire is provided to prevent
the closing link from moving off of the roll

arc chutes inspected for excessive erosion.

25-Plg. 4) over roller bearing at end

operating crank.

er bearing.

In case of any excessive

bration causing the link to roll, the book

on the link engages the wire and the
is held in place.

link

On a nomal operation of the solenoid

the link operstes without touching the wire,
but if the mechanism overtravsls, the clos

ing link may strike the wire causing It to
bend or break.

A check should be made

see that the four bolts are tight and shims
should

added or removed to allow

the

holding toggle to snap over center 1/8".
SDMHART OP ADJDSTHENTS

be removed and the contacts, aro mnners and

Arcing contacts, arc runners and arc chutes

need not be replaced unless more than l/lo"
thickness of the material has been

eroded

from the surface. The chutes may be removed
by removing the supporting bolts (Pig. 2),

loosening the two upper coll bolts (Fig. 2),
and loosening the lower bolt on the second

ary coll connection (Fig. 3). The chute can
then be removed, leaving the upper blowout
coil assembly on the bushing. With the arc

chutes off, the condition of the runners,

oontaots and arc chutes can be determined.

Scale formed over the surface of the
chute must not be removed, but loose scale
collected in the muffler should be removed.
Cranks which have formed in the fias of the

Primary contact finger travel - 3/16"
±1/32".

aro chute are to be expected In ceramic ma

Distance between primary block and
fingers, arcing tips just in contact

with the operation of the device In any way

1/2" to 9/16".
3.

Contact blade torque - 40 to 60 inchpounds .

Toggle distance - l/S" to 3/l6".

Tripping Boohanism adjustments.
A.

Clearanee between trip hammer and
trip shaft raised and trip hammer
(Mder center of trip shaft - 1/32"

±1/64".

terials of this type which are subjected to
severe heat.

and

These cranks do not interfere

should be disregarded.

If the

chute

has had any mechanical injury such as drop
ping or aoeidental striking of the fins
which has resulted in actual breaking off
of complete fins, replacement of the chute
is necessary. The insulation parts on the
breaker should be kept clean and dry.
if
the aro chutes show signs of moisture dur
ing any of these inspections, heaters should
be installed to insure dryness.

The surface of the bushings should be
smooth and unscratehed.

If the Insulation

surface of the buahing should become damaged -

(inalde or outtlde tba breaker) the sur•1th
1th either 1170 ole«r Tarnish, retouched
or 1202

in«
Alloe «
to

(browi)
61 yp tal •
dry hard
and aMOoth.

shich may be caused by broken, bent

or dirty parts.

cn as et

•oohanism parts against these given.

In the oaae of replaoeaant of eontaot
t
the eontaot
blade andI'w***®
buahlns ahould be on
lubricated

l«t

D. Check the adjustaents of all the
5. Lubrication:

lubri2t
manner?

'' Voeuuj# grease SP-323 or equlTa-

1. ^ep ^e aechanlaa free of all "gritty*

*'»® "•obanlsm are
'»etopy in the follosing

A. All naia bearings such ae operating
orank, closing Unk, tripplM haaeer

deposits, end roasonably clean of "llnty or dust-like substances.

and manual closing Crank, vlth 6 H

laibricant 090H1C (Lubrlplatc #110)*

8. N^e regular Inspeetloos to see that

tte aechMlso is adjusted properly and

B. Operating crank roller bearing vlth

that no defects haee dcTelcped.

e.g. I^rlcant OSOHIO {#SC-618 from

Standard Oil Co. of Pennsylvania).
3. In the ease of tlae delay current trip

C. Finished mirfaeee and baaringe of

aechanlsas, reaoTC old oil f roa dashpots, flush with sons non-oorroslTe
fluid, such as carbon-tetra-

®?f® This should
refillbeeith
dashpot
oil.
donefresh
at intervals
dependent upon the conditions of insUllatlen, but never leas frequent

than once In six months.

4. In the event that the aechanlaa fails

trip shaft, hardened end if VrtJ:

ifilf

of closing

ard Oil Company of Kev Jersey.

recoaaendod that these lubrloants
or their equivalent
be uaed during mainten

ance at least once a year.

to operate properly:

RBICVAL PAWS

A. Cheek applied voltage vith that given

ti .. f?** renewal parts refer to Renewal Parts

on the aechanlsm naneplate.

B. Check for burned out eolle or loose
connections.

C. Look for binding in the mechanism

CBO-4422. Vhen ordering, address

Sriir

spBolfy the quantity, de-

•®^®" ®'''lLoe of

the Oeneral

tion that appears on *^*®
the name piate.Informa
Also
the requisition number under shleh the

breakers were purohased if it is available.

Registered Trade-nark of General Hectrlc

company.

tp-

Muffler

FIG. 2

ARC CHITTE END OF MAGNE-BLAST

BREAKER WITH BOX BARRIER REMOVED.

3
7

^ S!«

g»

h i(i I

ai a
'Je s
&r

III

I II !1 !) I i^V°?Ti If ^

' Tillsii»
fi i

I.J
III

o
Ln

«3
o
o

*!o
<

?:S
^ Q.
£ Q

03 m 2
eg"
!= S

§ogi
rt' «0

&5
iL
2
\D
<

)

Stop

'ToaritkOn

ii%ia Y4>ipfA«me

wuH or\t,'r«Ma4»\i^c or

four Trip^itavlro&antorkfooa
Or Itfwia OtU^.

ffl

—®{i
V««4Jar
CO^^l4r

^6h*rnp»lS Ad4li^c^(^S^og♦)AI«

Adjusting Turnbuck.la
AuulCa/^ 5»vitch and

Indicator Dri\»»ng Linkage

for-

noldtng Toggle

|5lot in Frame foiP-arallel Motion

Shim with
a9h«> to Obtain

Clctar-anca

*-««cM-canc«

between end of Tripping
Hammer « 6 and TripShaft
the Raised Position

Note

Part Nurnbers Refer to Those on Figs. 4 &5

FIG.6

profile of mechanism
WITH COVER. AND 5IDE
OF FRAME REMOVED

FI6,7

FRONT ELEVATION OF MECHANISM
WITH COVER, TRIP COILS AND
AUX.ILIARV SWITCH REMOVED

a Ope^lirtg Handle
Mdou^
To Close
Adjust Bolts to Allow

Toggle to 60 Over- Ceni«»" X'*®i

LocKir^g vUiru Uxd to
Prevent Clos>nQ Link,

from Torr>«r»g Oft Roller
Bearing Until Irip
Hamrnor is Released

Apririg for Closing

?'^"Ma*>rT«u»Ti SwoVe I
of Armoxur-o

FJS.8

MANUAL CLOSING MECHANISM

UiriK.

_ I

FIG. 9

SOLENOID CLOSING MECHANISM

OfNERAl ElECTftiC SALES OFFICES

MAOr to UMIt TOV . . . MW Xm, Mr*

. , .
*

lOMSIANA

**•? 0»»ia COM MY

tcvlamil (ImMIm

•

730 Munav St.

AIAIAMA

; 11

«»i

»iji

Avivtia

a**.

AKAMAI

CAtirOIMIA

Waccaawi 0160)
MICWOAN
Otitaii 41101
' I t
41)01
_Hint ,
. ,

AIIIOma

; I 1 *Aenl. »MII
I

S).

*j^ c*-t,ol Ar.

IvttcB Min

. .. Ill 1.

n,*.

• « MmA. Util* t*A ntlA
•t
•Aii«* AMI ..
u
- -••CiOA.(.O,W«M*elR
71601
(ox 109)
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Vitxm*«•
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11 Ui Aoa«l,i foao)

, 131) WUtlw* Nvd.

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t*di>««4 Cuy t606)....

t
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tl'i'H*!.*Wvd.
U.
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JoxroMRI* tMIA
I Son bUo* fllOl

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loo Jbi* Kill

313) S*. lint SI.

•tn

0*»*« 40M1

fI -t

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777-)4rii Si., M.W.

llOlrOA

< Cocao (aacA (Cao* Conovtc*! Olfin)
-Cocal
• .• Cobl*!
i
19146

4100 Wail llaaw Si.

lam«(«la 11)0)

Writ

(Ida.

Tomoo 33600 HiodirBoii Ilvd, al lali Ava.
Tampa 13601
1106 S. Uii Am.

*1I

(*at*i Citr 6410)

Si. UvU 63101

iillinoi 10101

6«I1* 10701

Omaha 6(103 .

*1S

• 11

Aila.w 3U00.. . . 1160laacAlia* ld„ M.W.

t .t

S?"®*
Savaaooh

HIW YOK

V.
1140)

0«'r Si.
1003 laalian
Si.

aOAHO

Oali* U706

J)14 Idaho St.

IMINOIS

M t I Chitag. 606M

040 S. Canal St.

!*•??•
♦'*®'
lachW 6110)

- .411) tail^"r
Av*.
Slola St.

SatmolMd 61701

607 S. Adomi Si.

•NOIAMA

•' t

fva.tvilla 47714

1700 Waihin»>*n Ava.

T fan Wayna 46607......

II. f®2
*HSt• !1 South
1"'^?*^®®!;'
|*xd 46601

163) Oroodwai

»• Colhavn Si.

Al*ridloi> Si.
St.
410 N. Mi(«H«a»

IOWA

I.
•r 11

S*®"
Dav*«porl SlIO)

310 Socond Si., S.t.

. .
•;

D*t M^i SOlie

St., Stritandaif, lawa
Mil Mad* Nav Rd.

KAMA)
•T

.
•
•
•

110 S, Indionapalli Av*.

®S1?I?
tauiaviUa 40111

•''*AWadaw
t- H'oh b».
St,
_ 3300

•
. I Colvin Av*.
... 10 Chanongo Si.

I Albany IIM)

t
6«ngltaml*n 1)001
11
SvHala 1410}
I i Naw Yaik 10011
I I
iMhtiiar 14604
•

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Syrwvn 13106

Wavvtly I4)K

570 l*alngi*n Av*.
to
. .153}
1001
. f.O.

Utica 13)01

• 11
•

ClwilalK ISlOl
Ciaambaia 1740}

• t

lit W. Tiad* St.
601 Summit Av*.
... 16 W. Martin St.

(alfigh 17601

NOtlH DAKOTA

lltmaiih )))0I
Ahian A43t3

Canton 44701

ISSI W. M*ih*r St.

It) Third Si., N.w.

• Tt

Cincinnati 4)106
- . 3611 Vinery fhwy.
I i I Clwalend 44104 . . ... 4066 Wasdiand Av*.

Columbut 4311)

S
i

1
1 I

Colvmbui 43113...
Oayion 4)401

I 6ayi*n 45401..

305 I. traad St.
W7 IuikII Av*.
II W. MenuM*nl Av*.
..._.

Ill W. flnt St.

Maniliald 440D6 . . ...564 fell Av*.. Watt
TaUda 4)606 .
. . . . — 311) Oeudlai td.
Yowngitaivn 44)07..

173 £. Indianolo Av*.

f.O.

ICM

us MfSa It*, uli

4b«t*M 7N0I...

Mi CsAer It

Ocaumani TUS'"
77701..

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rtlOl..
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601
t}|)AmaiUle
Coldtr Ilvd!
Am

'•*»,....36) H?^piS
•'ooway
911 M. iteAlMJk
tl

W, kvMrti St
63l01"chmond Ava.
t- SOlIt
it_ *®
tff North
M la

Mfiliend

San AnNni. 7(304 .:7.611 i,^« Am!

UTAH

• t

I Sad lal* City 16110

• 100 I. Main Si.

VtlMONT

(ulland

-UVO Canlat St,

VIIOINIA

•

I Ncwpaii Neat 33601
f.O. Ic

• I

«ichmand 31110

• I

(eonaha 1600S

I 1011. 311 TKiirSt

. .9001 W. (raod Si.

..on S. 7*H*nan $i,

WAIHINOTON

luua 11301

•t
•

. 126 W. lawia Si,

! Saani* 1(106.... iilZ" ._7I0 SaceM Ava.
SpaSan* IKIO
_^.S. 162 leu St.
1
S^an* 11210..
..I, 160) Irani St.

WffI VltOINIA

(

Chorlaiion 2(31(..106 Ma(C*rkl* A*6., S.f.
JowOl lid*.
Wharling
_^40 reun**Aih
K

411 taiiti Av*.

OHIO
• 1
• 1

Sett Av*.
7am*. Si.
liaad Si.
la* 301

HaiuMh A**n
......1410
Union ftW.
Av*,

—

..61) Dala>v*ia Ava.

NOtTM CAIOIINA

'*•

Wichita67311

KINIUCKY

11II.

... 16 WethinglAn SI.

Alhvav*'*** 67106 130 Mad*iie Driva. N.C

1711 S. (ih St.
166} (Im St.

m Oaotfia Av*.
— T* Commaic* St.

Mamphtft 11104

•I II

400 S. S*v*nl*«nih St.

Soil Orano* 07017

^ *t.
IM W, WaiMniian
St.

TIXAI

SI.

30) N. Iieadveir
103 N. Wyoming Si.

NtVAPA
t
Lai Vapai (1106
NtW ftAMlSHIIt
1
Manchfflltl 01104
N(W KlSiY

£"'**^^221.
Gi**av.ll* 10602 .

' * IAIt?*':'!!*
M Ifdt*

. .. iOD lacuit St.

SI N. ManlfM H.

MurfftttftbOf#

IIIOI W. fifth St.
106 W. f*vna«Aih St.

MONtANA

71) WaiMn(i*A Id.

Yarn 17403

. II

1.0, 6«* 3)
.310 S

NiW MSXICO

OlOtOIA

Japlm 64103
t

I MaAwgh
1)311.
~

• I 1 I CImnanaaM 17«}
•t
5'"0'%''

. 14 W. Supetiar St.
106 [, Waihinoton St.
I) S. Sixth St.

NIUANCA

AlUaiiJc
Ava.
3)0
lied laod
1001 H.II Si

iatkioovill, )1101
Miami 3)1)4

;

Cvlleait 11)01
Tachian WIOI.

C.)

I** *»•

SOUTH CAiOllNA

S»d "*?'!
0610)

•t

II Si. Jam*! Av*.

Duluih 1M03

_ 1170 laRl it

-II
»S"Av*.
R:
mi w*N.w, Mlh

.* 1.
flT '**' .ahvU'®'
flVM
Ml 6^ »»•
t*
' 1I IJ ' Oittthvc^
ThiladatphlaI.SW
lltOI
)
CoMW Maaa'
Th* OHv** 6id».MNi*a
la.

If Salt fianiilin St.

700 Anioloativ )i,

fai«vc fell! 66311

liNNSriVANIA

3U Omv* Si

"M.

I ftavth Choil**

MISSISSIMI

COtMAOO
CONNiCTICUr

tv*f»i 07401

l*.il*nd 17310

f'wrwi®!
U>f»« 41001

lA?"""

; t M io« l.wujo 14106 .. MSM..li«oUfr $1

•'

I!.
It

3I6V7 W. Cavit ).,
Cr*»d laaan 41101 ... . . 1)0 w, franhlM St.

MINNtSOfA

. 1601 "I" Si
lltO liiil Av*'

..... .

OtfOON

113 Siai* Si.
... 77 Canaal )i.

h*n(«l 04401

AUIYIANO
« I I
SaMimai* 11101 .
t
Naaavifamn
MASSACNUHnS
• l i t hmiR 01117
Sadn««nW 61101

16401

fwt»« 741N

CUvniKo lidl.. list i.'ifaVsi.

Ill Caavi*. Si.
4747 Caihaii Mvd.
. 40O liavit St.

MAINS

IJI

631 Oah Vill* tivd.
1414 Arwi St.

I N*vr OtWam 70111
N*» Ohmm 7011)
Sl»*v*aail 7II0I.

«
*t

MUtMlM

6ai*n («vp* 1011) ..
loA* CImlal . ...
I

t Mrm m»4 M**!. H««mM W*.
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lid.

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• I

I Apalaian S40I0

• 11
If

510 W Callan* Avn

"JSvt
""alS: W.
*"*">{•»>
Milwauh**
Mil) •......140
St favl W
Av*.

CANADA; Cmdian Oanaial ||*cnl, Caomany,
HAWAII: Amftican (anait, ltdn l.O. (aa ««a
Haaalvhi Miei

GENERAL ELECTRIC SERVICE SHOPS

WHIW you HSie titvct . . ih*.* 0>l **1*11* ilMpi wW >*p*ll, t*c*ndi<

Heudd yaul alacfm •ppamtua. Th* hacUivia* *1* av*il«bl* d*y «nd

pwTwamnc* af ya«r anvipmant. fat full infatmatian abavt daaaa aaivM..

waian ymi, naai**,

"Nw ffXHmt,

f*ct*nr malhadi *ad faa*!** O-f a*««w*l pant a«* uiad N maialain p*ak
AlASAJAA

KANSAS

lirminghom 11)11, P.O. lax 16<7

—

'(Sliaihti) Afhaniai
•ai Cli
Cliy...,

3-iiih"$c, "i'w;

ARIZONA

.6111 Wall Colbi St

Im A^Im nooi...

•(lac Angabi) Onlaib

t\Ai""J-o;yjv^'"*"
OeAland
04600

i«"wn»nle 11614
So* fmnciKn 14101

.6100 Swnlatd Ava.

'tttwnalianat
AliriiiM
3400 Waad
St.
11 hanh ITlh Si,
ten Hanlaaa $|.

louiivifi* 40301

"••Yw tom^

191} Uilmac Si.

coNHscncur

tOUISIANA
Naw Ofbaai 70117..

SalMmot* 2I3J0

130

ItNNSYlVANIA

fJhUlSZ
JPIMHIAWf) '.lug
Ijt03
—t- ^41
Sr
»i.
Ihiladalphi* 11124
toio I. Ida Ava'
{filiibv^ Hamaatam) UI*L__

fan Ava.

MAItACHUSfni

(leilanj Atadtwd 03IS3

40)0 lunmrnllk Hallow (d., to dl,

. mo Myiib VaHar Poihwey

—

l>»U0" 6(202

Stx Third St.

AUHMtSOIA

Minnaepati. 1)410

{S*uihl*«l*n] naMavUb OAOl
»0 Aiwotar St

Wati MMdin, Po. 15122

lonw City 64110

T*m*a 9)601

P.O. lax

J5??- (•diet* 14)11

MIoi 71331

IfiS OMdnat Av*

AUdland 71704._..___35ri JobSmfc

TH) UtI laM

1731 UaaU Am.
*• Vanawt U.

(bannnaif) iiWi iduif 12724
109) Snn. sc.

Namien 770»

——

NOIIM CAtOUMA
0NI0

UTAN

311 ucimi*«•
St

6C01 laimaa* Av*.
(InalniananiiNi Satvkai 1230)
- -' Itvac r '

Omclalb 3K1M

2336 (lidff I

Cjnd*na« 63103

446W. tWcd Sc.

aant

yh^

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1401 hnnm Am.

..TO-»•« w,1ifs"Ae4SwSr7wr'$E

WASNIMOTOfl

SaoHb H1S4

•S*oitb NIM

94B (|n| Ava

aiagn^Y

Seikm tl)OS..._-.ZZirm WmSo "•
Sl
WBI VltOMIA

TrtirniriiT!*****"

•C aciimuli 632a3..._>60 W. MMwD At*.
44121

... — •

•W-2M^M4

'..m.

_ -jv ftanh
-. (aipaa.
»*>• W.
An.
(Hmv V*A)
H. latakath
J. OTDC......

•IIINOTS
«»N«1»,..«h-NM«vd.
INOMfr-®"
6M0W.d7*S,.

•(Maw YMh) llndan, N. J_

WOieiA

(Alienie) ChwwMa. *eOS._

TUAS

703) 61lh A**> N.

H(W Y06K

S;
1361

ZS4 N, Hanbao Si.

Y»ih 17401.

AUtiOUM

iL>~"

ladianviia lao).

8^4.7

Ills Da Aimai St.

Tab4*--4366s':^]!fj!.'&?*i^
OMOOh"^"^
t. iMbSSb in.
fanlond 17210
....3727 N.W. Jlih Am

MARYIAND

•lORlOA

K Wpya* 4Ma

1100 Clillandaa Onva

Cahimbvi 43221..

MIOHIOAM

COlOIUUlO

•OWA

KfNTUOCT

(rnaanii) Clandab IMI
CAllfORNIA

6-L. Ca. l,'67"la* 777

4477 lou 4M St.

6MEMI EUCTtIC COJilPAKy, PHIUOElfNiA, FA.

•"** ***<***»

34110 .-AUdwK Ixdodrial Ana

f.O. lax n CaiMyTnmk P

MilwmiAas 9)3}).......O40VW.

It M

L^ilaUOLa

m
lYPE AM-S-'

r-\ rnpi

(NCG 8009080)

Fig. 1. Type AM-5-150 magne-blast circuit breaker

OElEi^L
io'cHori^e wifhcv'l'riCf«'ee.

ELECieie

)
c:

SECTION

QtL

AA
2000A

600A 1200A

9,10,11

A/yi n

«4
•<
•a

7777

s
Cn
I
w

13,14,

15,16

tn.

S
>

o
z
m
•

cs
F"

>
V>
H

Q
ft

2Q2I

B
m

>
TZ
m

/7J n fj

f] tJ

lOWG ei39436l

Fig. 2. Cross-section of breaker

VVi-'c

o (£ F*3 41> u ij

CtkCUit

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

Number Required for AM-S-150600 ampere
1200 ampere
2000 ampere

Fig Ref
No.

3
3

2
2

2
2
2
2
2
2

4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4

105

6
3
3

Description

Cat. No.
7
3

6315499? 1
622997503

Booster cylinder
Stationary arcing contact and arc

6547728G1

Stationary arcing contact and arc

6193967G18
6193967G17
6412207G1

Upper Insulation
Upper Insulation
Upper Insulation
Trip coll
Closing coll
Stationary Intermediate
contact assembly
Stationary Intermediate
contact assembly
Stationary Intermediate
contact assembly
Stationary Intermediate
contact assembly
Stationary Intermediate
contact assembly
Stationary Intermediate
contact assembly
•Contact support
•Contact support
•Contact support
•Contact support
•Contact support
•Locking plate
•Spring guide
•Support for spring
•Support for spring
•Support for spring
•Spring
•Spring
•Spring

runner

4
4
4
4
4
4
4
4
4
4
2

♦

3
3
4

6
1
1
3

6
1
1

6
1
1
3

6
1
1

1
1

6
1

3
3

1
1
3

6
1
1

6316606G18

6316613G23

6316613G15

6193967G19

3
3

105
105

3
3

6316613G24

6316606G12

6318215P6

See page 11
See page 11

6551072G1

6217066G4
6217066G5
6217066G6
6440519
6440517

105

105
106

3
3
3
3
3
3
3
3
3
3
3
3
3
3
107 12 12 12 12 12 12 12 12 12 12 12 12
108
3
3
3
3
3
6318217P2
108
3
3
3
3
3
6514168P1
108
3
3
6318217P1
100 12 12 12 12 12
12 12 12
6370616
109
12 12
12 12
6509731
109
21 21 21 21 21 21 6172977
110 3
3
3
3
3
3 3
3
3
3
3
3
6440518
110
3
6440994
110
3
6243070
110
3
3
3
3 6508104P1
111 12 12 12 12 12 12 12 12 12 12 12 12
6476798G1
111
21 21 21 21
6440995
111
21 21 6477100G1
1
112 3
3
3
3
3
3
3
6300108P1
112
3
3
3
3
3
6441944
112
3
6441104
112
3
3
3
6300107P1
112
3
3 6441943
120
21 21 21 21 21 21 6243072
7
3
3
3
3
3
3
3
3
3
3
3
3
6316606G13

5
5
5
S
5
5
5
5
5
5
5
5
5

150
150
150
151
152

152
153
153
153
154
154
155
155

ir.n

3
3

3
3
.1

3
3
3

3
3

3
3
3

3
3
.1

3
3

3
.7

3
,7

3
3
,7

6420220G4

3
3
.7

3
:)

6420220G8

6076405PS60
6247780
6440108
G3262ggp2
6275256G1

6420221G2
6420271G1
3 6420272G1

3
,7

6316606G1S
6217063G8

and primary
and primary
and primary
and primary
and primary

•Retainer
•Retainer
•Retainer
•Retainer

•Stationary primary contact
•Stationary primary contact
•Stationary primary contact
•Shield
•Shield
•Shield
•Shield
•Shield
•Insulation

Movable primary, intermediate,
and arcing, contact assembly
Movable primary. Intermediate,
and arcing contact assembly
•Contact arm
•Contact arm
•Contact arm
•Pin
•Pin
•Pin

•Movable Intermediate contact
•Movable Intermediate contact
•Movable Intermediate contact

•Movable arcing contact
•Movable arcing contact

6245402P1
0440115

•Pin
•Pin

Ol-ltmila

•.'tiM'liiit Buliln

duldom required. Assembly only recommended for normal maintenance.

and primary

Number Required for AM-5-150Fig. Ref.
No.

600 ampere

No.
3

5
5
5
5
5

5
5
5
5
5
5
2

'2
2

2
2

'2
2
2
2
2
2
2
2

2
2
2
2
2
2
2
2
2
2
2
2
2
2
2

156
157
157
158
158
159
159
160
160
161
161
8
8
8
8
9
10
11
12

13
13
14
15
16
13
14
15
16
17
18
18
18
19
20
21
22
22
22

3
3

3
3
3

3Z 4

3
3

1200 ampere
6

3
3

1
3

3
3
3
1

1
1

3
3
3
1

3
3
3

3
3

5
3
3

3
3

3Y 4

3
3

3
3
3

6440172
6172869
3 6509745
6172949
3 6509746
6174948
3 6509747
6149967P1
6149967P2
6193967G23
3 6316606G23

6420344G1
6420344G7

1
3

3
3
3

3
3

2
1

1
1
1

3
3

3
3
3

3
3

3
3
3
1

3
3

3
3
3

1
1

1
3

3
3
3

1
2

1
2
1

6420344G3
6420344G5
6245722

6440166
6420266G1
6420266G2
6420266G4
6420266G8
6420266GS
6420266G3
6420266G6

6420266G9
1 6420266G7

1
3
3
3

♦Intermediate spring
♦Intermediate spring
♦Inner

spring
spring
♦Insulation cup
♦Insulation cup
♦Inner

♦Tube and piston assembly
♦Tube and

piston assembly
Front bushing
Front bushing
Front bushing
Front bushing
Upper barrier (inner and outer)

Pin for operating rod
Insulation, horizontal
Insulation, horizontal
Insulation, horizontal, left
Insulation, horizontal, center

Insulation,
Insulation,
Insulation,
Insulation,
Insulation,

horizontal,
horizontal
horizontal,
horizontal,
horizontal,

6547718G1

2
2
2
2
2
2
2
2
2

2
2
2
2
2
2

2
2
2
2
2

24
25
26

26
26
26
26
26
27
28
29
30
30
31
32
33
34
35
36
37
38

3
1

1
3

1 6420316P2
3 See page

2
2

6
6
6

2
2

6
6

1
1
1
1

1
1
1

2
2

6
6
6

2
2

6
6
6

6
6
6
1
1
1
1

2
2
3
3
3
6

2
2

2
2
3
3

3
3
3
6

3
6

1
2

2
3
3
3
6

1
1
1
1

2
2

3
3

3
6

left
center
right

Contact arm assembly
Support, left
Support, right
Spacer
Spacer

^acer
Rear bushing and arc runner
Top plate
Arc chute assembly

assembly
2

right

Front barrier assembly
Front barrier assembly
Front barrier assembly

spring
spring

Solenoid mechanism

♦Outer

6193967G30
6316606G30

♦Outer

See page 13

3
3
3
1

*Spring guide

Upper barrier (inner)
Upper barrier (outer)

1
3

3 See page 0
3 6370753G1
3 6370753G2
6247905
6440983
1 6551053P1
3 See page 7

3
3
3

1
1
3

3
3

1
1

Description

Cat. No.

3Z 4

2000 ampere

6193967G29
6316606G29
6316613G16
6193967G28
6316606G28
6316613G17
6316606P1112
6316606P1107
6245461P2
6245814P1
6245814P2
6172960

6243996
2243035
6172976
1 G551054P1
1 6551054P2
1 6551054P3
1 6508798P2

Seldom r'^^uired. Assembly only recommended for normal maintenance.

Box
Box
Box
Box
Box
Box

barrier
barrier
barrier
barrier
barrier
barrier

Wheel

Wheel (swivel)
Bearing plate
Bearing
Bearing
Spring
Contact washer

Cup washer
Spring

Baffle, right-hand
Baffle, contor

Baffle, loft-hand
Spacer

GEF-34ti6S

m
52.53

62.63
Oi O
lOWO 69477271

Fig. 3. Arc chufe assembly
PARTS SELDOM REQUIRED

Number Required for AM-5-150Fig. Ref.
No

3
3

2000 ampere

1200 ampere

600 ampere

No.

3Z 4

3Y 4

3
3

25
3

50
51

,rN

3
6

51
52

3
3

3
6

Arc chute assembly

6193967G36

Arc chute assembly
Arc chute assembly
Arc chute assembly

6316613G36

6193g67G39
6316606G39
6412203P1
6318216P1

6316613G35

6
3

Arc chute assembly
Arc chute assembly

3
3

6193967G35
6316606G35

6316606G36

6318216P2
6412203P3
6420258P1
6420257P1

6420258P2
3
3 6420257P2
53
6370587P1
54 12 12
12 12
12 12
12 12 12 12 6476726P1
12 12 12
54
12 12 12 12 12
6318166P1
6
6
6
6
6
55 6
53

3
3

58
58

3
3

3
3
3
3
3
3
3
3
59
3
3
3 3
60 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12
61 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12 12
3
3
3
3
62
3
3
3
3
3
3
3
3
63
3
3
3
3
3
3

6412204P1
6412204P2
6318159G1
6412205G1
6440528
6440976P1

6193967G25

6149517

69
70
VI
72

3
3

3
6
3l> 311
3
3
6

6
:iii 3t>
3
3

3
0

Insulation
Insulation

Side shield (right
and left)

Side shield (left)
Side shield (right)
Lower arc runner
Lower arc runner

Insulation
Insulation

Filler for muffler
Divider

Right-side shield
Right-side shield

Molded cap

Brace (right .andleft)
Left-side shield
Left-side shield

Washer nut

Brace (right and left)
Brace, right
Brace, left

407193
6229976G1
6229977G1
6193967G26
6105830P1

Arc chute
Arc chute

421711

3
6

,r^

Description

Cat. No.

6316613P516
6440155
6440977P1
6440977P2
0551057P2

Coll and terminal
Coll

Muffler assembly
Side plate

Spiicer
Insulation
Insulation
Insulation

Spacer

31) 311

lU>r>l01)filM

Ntil

6551022P2

Insulation (lel't)
Insulation (right)

6551022PI

6551057P1
N402P11B

Spacer

Ctif'-'jAIMsU

TYPE AM.5-150 MAGNE-BLAST CIRCUIT BREAKER

J
.lilKs

113 ^

112
(DWG 642IB9I)

?"1

(OWG 6547783)

Fig. 4. Rear bushing and arc runner assembly

GEF-3486B

XYPe AiVk-^j-150 MAGNE-BLASY CiilCUit
Number Required for AM-5-150Fig. Ref.
No.

No.
3

2
2
2
2
2
2

2
2
2
2
2
2
2
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4

4
4
4
4
4
4

4Z 5

3Z 4

3Y 4

3
3
3
3

3
3
3

3
3

3
3
3

9
9

9
6

3
9
9

3
9
6

3
9
9

9
6

3
9

9
6

3
3
9

3
3

3
3
3

3
9

3
3
9

3
3

3
9

3
3

6
3

3
3

118

4
4

119
120

6420344G6

bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc
bushing and arc

Bushing,
Bushing,
Bushing,
Bushing,
Insulation

6370595P6

Spacer for bushing

6370595P5
6316613P22

Spacer for bushing

6441975

l^acer for bushing

Insulation
Insulation

6217066G5
6440519

Contact support
Contact support
Contact support
Contact support
Contact support
Locking plate

6440517
6318217P2
6514168P1
6318217P1

Spring guide
Support for spring
Support for spring
Support for spring

6370616
6509731
6172977

Spring
Spring
Spring

6440518
6440994
6508104P1
6243070
6476798G1
6440995
6477100G1
6300108P1
6441944
6441104
6441943
6300107P1
6187411P5
6551070P1
6551064G1
6187400P4
6113702G2
6547740G1
6148748
6187411P8

Retainer
Retainer
Retainer
Retainer

6551072G1
6217066G4
6217066G6

6551052P1
6229975G3

6547728G1

3
3
3
3
3
3
21 21 21 21 21 21

6370595P4
6243072

runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly
runner assembly

rear
rear
rear
rear

Bushing
Bushing

Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear
Rear

6187411P7
6440159
6316613P21

6318215P6

3
3
3
3
105
3 3
105
3
3
3
3
3
106 3 3
3
3
3
3
3
107 12 12 12 12 12 12 12 12 12 12 12 12
3
3
3
3
108 3
3
3
3
3
3
108
3
108
3
12 12 12
109 12 12 12 12 12
12 12
12 12
109
21 21 21 21 21 21
109
3
3
3
3
3
3
3
3
3
3
110 3
3
3
110
3
3
3
3
110

6193967G22
6316613G26
6316606G22
6316606G16
6316613G13
6316613G20
6193967G21
6316613G21
6316606G21
6316613G14
6193967G31
6316613G22
6316606G31
6316606G17
6420344G2
6420344G8
6420344G4

6187411P4

4
4
4
4
4
4
4

Description

Cat. No.

3
110
111 12 12 12 12 12 12 12 12 12 12 12 12
21 21 21 21
111
21 21
111
3
3
3
3
3
112 3
3
3
3
3
3
112
3
3
112
3
3
112
3
3
3
112
3
3
3
3
3
3
113 3
3
3
3
3
3
3
3
113
3
3
3
3
113
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
114 3
3
3
3
3
3
3
3
3
3
3
3
115 3
3
3
3
3
3
3
115
3
6
6
6
6
6
6
A
6
6
6
6
6
6
6
6
6
116 6
6
3
3
3
3
117
3
3
3
3
117
3
3
3
3 3
3
3
3
3
3
3
3
3
3
3
3
3
118 3
3
3
3

4
4
4
4
4
4
4

23
23
23
23
23
23
23
23
23
23
23
23
23
23
100
100
100
100
101
102
102
103
103
103A
104
104
105
105
105

2000 ampere

1200 ampere

600 ampere

Stationary primary contact
Stationary primary contact
Stationary primary contact
Shield
Shield
Shield
Shield
Shield
Insulation

Insulation _
Insulation
Arc runner, upper

Coil, upper
Coil, upper
Bushing
Insulation
Insulation

Stationary arcing contact, arc
runner, and coil
Stationary arcing contact, arc
runner, and coil
Spacer for bushing
Insulation

153

155

152

151

150

146

(owe 6421889)

Fig. 5. Contact arm assembly

GLK'343Sa

TYPE AM-5-150 WlAGNE-BLAST CIRCUIT BREAKER
Number Required for AM-5-150Flu, Rof.
No. No.

600 ampere
3Z

19
19

140
140

2000 ampere

1200 ampere
3Z

3Y 4

Cat. No.

Description

6193967G34
6316606G34
6193967G27
6316606G27

Contact
Contact
Contact
Contact

arm
arm
arm
arm

assembly
assembly
assembly
assembly

6193967G24

Operating rod and

6316606G24

Operating rod and

coupling
coupling

141
141
142
143
144

6247781
6245820
6440197

6247776P1
6318226P1

Clevis

144

6318226P2

Trunnion and spring

145
145
146
147
148
149
150
150
150
151

6242806P1
6242806P2
6172873

Bushing
Bushing
Outer spring

6172874

Intermediate spring
Inner spring

Bushing

Trunnion and spring
container

V. /<•

container

6172875
6247777

Washer

152

6076405P560
6247780

Contact arm
Contact arm
Contact arm
Pin
Pin

152

6440108

153

6275256G1

Movable Intermediate

153

6275256GI

Movable Intermediate

153

6420221G2

Movable Intermediate

154

6420271G1

Movable arcing

154

6420272G1

Movable arcing

155

6245402P1
6440115
6149985
6440172

6217063G8

6420220G4
6420220G8

contact
contact
contact

contact
contact

155

156
156
157
158
159
160
160
161

6509745
6509746
6509747
6149967P1
6149967P2
6193967G23

161

6316606G23

Spring guide
Spring guide
Spring, outer
Spring, intermediate
Spring, inner
Insulation cup
Insulation cup
Tube and piston
assembly
Tube and piston
assembly

TYPE AM-5>150 MAGNE-BLAST CmCUIT BREAKER

.,)

221.222
252.253
187

239,240

J
243,244
183

184,185
201,203

192,193
•ntpTn—

Ik I I

(OWO 6392SSI)

Fig. 6. Type MS solenoid mechanism

Number Required for MS-

Fig. Ref.
No.

No.

Description

Cat. No.
10

lOA

2
2

4
4
4

1
1

1
1
1
1

lOB

lOB-1 lOBY

lOBZ

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

2
2
2

6275070G1
6275070G2
6174582G1
6174582G2
6275070G1

6174582G14
6306764G3
6306764G4

Trip coll, 24-volt, d-c
Trip coll, 48-volt, d-c
Trip coll, 125-volt, d-c
Trip coll, 250-volt, d-c
Trip coll, 115-volt, a-c
Trip coll, 230-volt, a-c
Closing coll, 125-volt, d-c
Closing coll, 250-volt, d-c

PARTS SELDOM REQUIRED
6

6
6

175
175
176

176

6
6
6

177

1
2

178

179
180
180
181

182
183
184

1
1
1

1
1

185
186

1
15

I
15

188
189
190
191

1
15
2

187

192
193
194
195
195
196

1
1
2

1
2

1
1

1
2
1
15
2
1
1
1

1
1

177

6301377
6301376
6370617
6301377
6370580P1
6476714P1
6193968P42

Outer spring
Outer spring
Inner spring
Inner spring
Guide for spring
Guide for spring

6370572P4
6193968G40
6193968G36
6371478G1

Buffer washer

Crank assembly
Crank assembly
Coupling

6420224P1
6318160P1

Link

Set screw, hollow hd, cup pt.,

1/4 In.-20, 1/4 In.
6
6
6

6
6
6
6

rr^

6
6
6
6

6
6
6

6
6
6
6
6
6
6
6
6
6

Link

198
199
200

6371491P12
6477424P7
6477418BAP15
6477400P7
6002721P391
6370577G1
6301380
6440990
6440987
6008491P10
6476710P1
6370589G1
6476712G1
6508713G1
6477418AAP5
6477418AAP2
6172825P1

6193968G38
6193968P102

Xatch assembly

1
2

201

6441148
6477418BAP10
6177015P12
6440148

202
203
204

1
1

197

2
I

2
1
1
1
1
2

1
1
1
2

2
2

197

2
2

Retaining ring
Needle bearing
Washer

Spacer
Prop

Spring
Pin
Pin

Washer

Piston ring
Armature and plate
Armature and plate
Armature and plunger assembly
Ball bearing
Ball bearing
Spring

Set screw, 8-36, l/4 In., headless,
cone pt, stl

6
6
6
66
6
6

6
6
6
G

205
206
207
208

208
209
210

211

212

G
G

213
213

1
1

6440154
6370579G1

6440137

1
1

I
1

1
1
1
1
1

1
1

1
t

6370586G1
6476700G2
6370581P1
6300924P13
037()r.m»l>l

GU7501G3
6318131P2

6508728P1

Needle bearing
Washer
Pin

Pin
Yoke
Stud

Plate and pole piece
Plate and pole piece
Pot
Washer

DoUoin pinto
Support
Crank
Crank

Number Required for MS-

Fig. Ref.
No. No.

Description

Cat. No.
10

214

6
6

214
215

216

1
1

217

218

6
6

219
220

lOA

lOB

lOB-1 lOBY lOBZ

6147122

6442807
6243920

1
1

Pin
Pin

Support
Spring

6176838
6245825

6192382P5

Operation counter

6117509P1
6243020P2

Crank

221

6440905

Buffer

222

6440938

223
224
225
226

1
1

1
1
1

6440904

Stop stud
Adjusting stud

6370592P1
6370610

Spring

1
1

228
228
229
229
230
231

232
233
234

1
1

6.
6
6
6

6
6
6
6
6
6
6
6

227

I
1

1
1

6055108

Support

Washer

6048842P2
6048842P1
6055109
6370572P2
6076413P279
6300046P13
607640gP188
6008491P2
6440134
6076407P180

6
6

6
6
6
6
6
6
6

6
6
6
6
6
6
6
6

242
243
244

245
246
247
247
248
249
249
250
251
252
253
254

6318278P1

Eye bolt
Cover

Washer

Support
Washer

Spacer
Bolt

1
I

1
4

I
4

6076406P118
6008491P3
6046816P1

Pin
Washer
Shim

6440951

Tube

6370509P1
6370509P3
6370572P2

Plunger
Plunger

8
1
1
I
4
4

1
I

8
I

1
8

I
I

1
1

Pin
Washer
Yoke
Pin

Washer

Semaphore

255
256

Stud
Stud

Operating rod
Auxiliary switch
Auxiliary switch

236
237
238
239
240
241

Cut-off switch

235

Bracket

6
6

6305650G2
6577001G1
6440134P1
6440143P2
6551045P2

Trip rod

I
1
1
1

6
6

6412114P2
6476341G1

6557052G1
6056154

Semaphore and bracket

6440147
6551084G1
6157223P2
6146194P2
6508688P1

Cover for semaphore

490072

Terminal board and hardware

Marking strip
Pin

Bracket
Washer

231

233

245

235

225 237 236
jiUUTf

241

238 248

25:

Fig. 7. Current frip mechanism for solenoid mechanism
Fig. Ref.
No.

No;

Cat. No.

No. Re

PARTS
7
7

225
226
227

6174599G2
22D3G226
6174599G6

Description

quired

RECOMMENDED FOR NORMAL MAINTENANCE

Trip coil, 3 annp for instantaneous only

3
3

Trip coil, 5 amp

Trip coll, capacitor trip for Instantaneous only
PARTS SELDOM REQUIRED

7
7
7
7

228
229
230
231
232
233

234

235
236
237

7
7

7
7
7
7
7

7
7

7
7
7

7
7
7
7
7
7

238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254

6371498G1
6476300G1
6074238
6371499P1
6076402P3
6318259G1
6076402P49
6076401P17
6440860
6193g57P209
6193957P34

Connecting rod

Adjusting rod and coupling

Spring

Guide

Trip lever

Shaft

Dowel pin for spring
Groov-pin

Guide for spring

Spring

Stop

1
1

Cover

Guide for armature

6370645

Torsion spring

6247927
6477094
6247919
6247927
6247924
6247926
6247925
6247923
G301205G1

t
t

Spring

6076402P72
6440885
6370644
6193957P203
6176575P3
6318258P1
6440865
6074557P3

255
250
21.V

258

259

6048813
6247920

Needle bearing for trip shaft

Plunger

Calibrating spring
t
t
t
t
t
t
t
t
t

Calibrating tube for instantaneous only
Armature for Instantaneous only
Guide pin

Armature for time delay only
Piston for time delay only
Dody for time delay only
Spring for time delay only
Well for time delay only

t Two for each trip coll furn shed
t One for each trip coll furn shed

Gei-2396te

INSTRUCTIONS

ilDT DESlOY

POWER
CIRCUIT BREAKERS
Mogne-blast Breakers
Types
AM-5-100-3, .3Y, -3Z
AM-5-I00-4, -4Z
AM-5-100-5
AM-5-100-6

AM-5.rI50-3, -3Y, -3Z
AM-5-150-4, -4Z
AM-5-150-5
AM-5-I50-6

AM-5-250.0, -OY
AM-5.250-1
AM-5-250-2
AM-5-250-3

With MS-10, MS-lOA,
MS-106, MS-10B-1

MS-IOBY, and MS-10BZ
Mechonisms

GENERAL S

ELECTRIC

.CONTENTS
. ... ..
RECEIVING BANDLJHG AND STORAGE•.. . ..
RECEIVING • • • • ••••• •••
. ••..
. .. .
.
HANDLING • • • • • • • • •
.. . .. ..
.
.
.
STORAGE • • •
. . . . .. . ....... ... . ..
DESCIUPl'ION••••
. . . . . . . .. ..
.. .. ... . ..
Mechanism ••••
.
.
.
Breaker Element.
.. . ...
JJIS'J'ALLATION • • • • • • • • . . • • • . . . .
PRECAVtlONS ••
. . ... .
..
AD1USTMENT8 • •••
.
.
.
.
.
..
Primary Contacts •••
...
Intermediate Contacts •
. . . .. .. .. .. .. .. .. ..
Arcing Contacts
. .. .
Contact Gap. ••
••••
...
. . . .. . . . . .
Latch WJpe. ••
Prop Clearance. ••••••
.. .. .. .. .. ..
Latch Clearance ••
. . . . .. . . .
Plunpr Clearance • •
.
.
Cut-off Switch •• •• ••• •
...
FINAL INSPECTION ••
..
.. .. .. .. .

PAGE

INTRODUCTION• · •• •• • •••• , •• • •

PRINCIPLES OF OPERATION

...
. ..
. .. . .
...
.
.
. ..... . .. .. .. .. .. . . . . . . .
.. .
. . . .. ... . .. .... . . . .

--!

•...

MAJNTENANCE ••• •• • •••
PERIODIC lNSPECTION •••
Contacts ••• , •
Arc Chute • • • • • • • • • ,,, • • • • ,
Insulation Parts
Bushings • • • • • • • • • •
Mechanism.
LUBRICATION •••••••••
REPAIR A.ND REPLACEMENT••
Arc Chute• • • • • • • • • • • • • • • • • • • • • • • •
Stationary Primary Contacts. ••• • • • •••• • •
stationary Arcing and Secondary Contacts ••• •
Movable PrimaryL. Secondary and Arel.Jig Contacts
Trip and Closing Hollers.
RENEWAL PARTS••••••••
ORDERING .INSTRUCTIONS
APPENDIX: • • • • • • • • • • • • • •
Latch-checldng Switch ••••••••
AuxWar, Switch Linkage, • ••
••• •
Current Tl'lp Mechamsm.
Plunger IDterlock • ••••

' . . ·1

...

•

..
.. .. .. . .
... .

•

5
5
5
5
5

6
6
6

'1
'1
'1
8
8
8

13
13
13
13
13

17
17

1'1

17
17
17

1'1
1'1
18
18
18

19
19
20

21
21

21
23

',./.

•

LIST OF . ILLUSTRATIONS \

·,

FIGURE
l
2
3
4
5
8
'1

8
9
10
11
12
13
14
15
18
17
18
19
20
21
22
23
24
25
28
2'1·
28

�.

TITLE

PAGE NO.

Left Stele View of AM-5-250 Breaker ••••••••••••••••••••• Cover
AM-5 Breaker After Removal From Packing Crate. •••••• •••• • . • 5
Left Side View of AM-5-250 Breaker ••••••••••••••·••• •••• 8
'1
Primary Contact Wipe, 1200 Amp • •• ••• •••••• ••• • •••••• •
'l
Primary Contact Wipe, 2000 Amp •••• • •••••••• • • ••••••• ,
8
Primary Contact Qap. • •• . . . • . • . • . ••. ••• • . •. • . • . . . .
Secondary Contact Gap, 1200 Amp•• , ••••• •••• •••••• ••••• 8
Secondary Contact Gap.z.. 2000 Amp ••••• ••••••• •••• • •••••• . 8
8
· Contact Gap, Breaker ·,·ripped • . •••••. •. •••••• ••••. • •• .
Left Side View of lfS•lO Mechanism. • ••• •••••••• •••• •••• • 9
Left Side View of MS·lOA Mechanism •••••••••• • •• •••••• •• 10
Left Side View of MS·lOB Mecbanlsm • • •••• •••• • ••••• •••• • 11
Left Side View of IIS·lOB·l Mechanism. ••• ••••• • ••• •• ••• •• 12
Cut-of! Switch (MS-108-1) •• • • •• ••••••• ••• •• •• ••••••• 13
Cut-off Switch (MS·lOA) • •••• ••••••••••••• •• ••• •••• • 13
Maintenance Operating Meehan.Ism. •••••••••••••••••••• •• 14
AM-5-150 Breaker Cross Section • • • • •••••••• •••• ••••••• 15
Right Side View of MS-108·1 Mechanism ••••• ••• • ••• •••• • •• 18
Rear View of AM-5-250 Breaker, •• ••••••••••••• •• • • •• •• 18
Rear Bushing Assembly. 1200 Amp ••• , ••••••• ••••••••••• 19
Moving Contact Assembly_,_1200 Amp ••••• ••••••• • • ••••••• 19
Front View of MS-108·1 Mechanism •••• ••••••••••• •••••• 20
Latch Checking Switch • , ••••• •••••• ••• • ••• ••••• • • •• 21
Auxiliary Switch Linkage••••••• •••••••• • • •• •• ••• •••• 21
Current Trip Mechanism••• , ••• •••••••••• •• •• • •• • ••• 22
Current Trip Mechanism•••• •• ••••••••• • •• •• • ••• •••• 23
Current Trip Mechanism. ••••• • ••••••••• • • • •••• ••••• 23
Plunger Interlock. • . • • . • . • . . •. ••. . . • . . . •• • _ •• . •• . 24
Plunger Interlock. • . . . •. . . . • •. . . . •. . . . •• . . . . • . . . . 25

·9

MAGNE-BLAST AIR CIRCUIT BREAKERS
TYPES AM-5-100, AM-5-150, AM-5-2S0, WITH IHS-IO,
MS-lOA, MS-lOB, MS-lOB-1, MS-IOBY, & MS-IOBZ MECHANISMS
INTRODUCTION
The Ma^e-blast Air Circuit Breaker shown on

the cover is a triple pole breaker vith an integral
solenoid-operated mechanism and is arranged lor

application In Vertical Lift Metal-CIad Swltchgear,

signedfor electrical closing only. The maintenance

operating device Is supplied only for use in mal^g

adjustments. NEVER ATTEMPT MANUAL CLOS

ING WITH THE BREAKER IN SERVTCB, for under

The AM-5-100 &150 breakers are available in

such conditions, sufficient closing force and speed
cannot be applied.

cated onthebreakernameplate, and all are designed

PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SATISPACTORY OPERATION OF THE BREAKER.

600,1200, or 2000 ampere ratings and the AM-5-250
breakers in 1200 and 2000 ampere ratings as indi

for application at a maximum circuit voltage of
5000 volts. These Instructions apply only to the
breaker types listed on the front cover.
The breaker-mechanism combination is de-

The various accessories that can be applied on
the MS-IO Mechanisms are described inthe appendix
under "Accessories'.

RECEIVING^ HANDLING AND STORAGE
RECEIVING

Each circuit breaker is carefully inspected and
is then packed byworkmen experienced in the proper
handling of electrical swltchgear.

Immediately on receipt ofa circuit breaJmr, an
examination should be made for any damage sus

tained during shipment. If Injury or rough hnni^iiTitr
is evident, a damage claim should be filed at once

with the Transportation Company, and the nearest
General Electric Company's Sales Office should be
notified promptly.
HANDLING

The crating must be removed carefully. Care

mustbetakennottodamagethe primary disconnects

{5) Figure 1. Use a nail puller to open the crates
and do not allow the primary disconnects to be

struck ty the tools while handling. Frequently,

"loose parts" associated with the apparatus are in

cluded in the crate. Care should be taken to malre

certain that these parts are not overlooked.
1. Thunb Screws

4. Wire Bends

crating, wire bands (4) (or wood clamping bar) hold

Box Barrier

5. Prloiary Disconnects

Cover

6. Lift Point

moved and discarded. Box barrier cover (2) seals

Seal

7. Box Berrier

After the breaker has been removed from the

ing the box barrier (7) in position should be re

the top holes during shipment. Seal (3) insures that
only authorized personnel remove the box barrier

when the breaker is unpacked. To lift the breaker

with hooks, an opening at (6) is provided on each

Fig.

AH-5 Breaker After Reeoval Froa
• Packing Crate

side of the breaker.

STORAGE

It is advisable that the breaker be set up im

mediately, but if it must be store^ it should be ke^

in a clean dry place, free from corrosive gases or

fumes. During construction work, particular care
should be taken to protect this apparatus from
moisture and cement dust as this combination has

a very corrosive effect on many parts. All machined

parts except the contacts should be coated with heavy
oil or grease to prevent rusting.

GEI-2396iB

Magne-blast Air Circuit Breakers

1. Box Barrier

6. Auxiliary Sxltch

11.

7. Lifting Lugs

3. Front Bushings

13. Booster Cylinder

8. Terainal Block

13. Booster

4. Frane

9. derating Bod

2. Bear Bushings

5. Secondary Cbuplers
Fig. 2

Vheel Channels

10. Movable Contact Am

Left Side View of AH-S-SSO Breaker

DESCRIPTION
MECHANISM

Each magne-blast circuit breaker is furnished

with an operating mechanism. This mechanism is

ball ends lor good contact and easy installation in
the vertical metal-clad switchgear.

The arc chutes, primary, secondary, and arcing

capable of closing and latching the breaker on an
energized circuit. A closing solenoid actuates an

contacts, and the two upper blow-out coils are

ture moves the linkage which closes the breaker

about the lower end of the Iront bushings (s}. The

ture-causes the linkage to collapse, allowing the

operating rods (9) which fasten to the solenoid

armature passing through Its center, andtbe arma-

contacts, when the trip collis ener^e^ itsarma-

opening springs of the mechanism toopen the

mountedonthe rear bushing (2). The movable pri

mary, secondary, and arci^ contacts are pivoted

movable contactarms (lO)are actuated by iimulatlng

detail under, "Principles of Operation!'.

mechanism. The secondary contact casting holds
the -booster tube (13) which connects to the piston
in the plastic booster cylinder (12). The t>ooster
cylinder-supplies air lor aiding the Interruption of

BREAKER ELEMENT

low currents.

The breaker element shown in Figure 2 consi^tf a fabricated frame (4) on which six bushings
(2) &(3) are mounted. The bushings are made with

ing insulating material where the arc is li^rrupted.
The box barrier is made of an insulatii^ compound

breaker contacts. This procedure is eiqilained in

The three arc chutes are made of an arc-resist

and segregates the three interrupting units.

Magne-blast Air Circuit Breakers

GEI-2S861B

INSTALLATION
Outline, wiring and all other drawings relating
to dimensions, electrical connections, and contiw
shouldheonhandsothatpoints in question are read'
ily settled as they arise. Before any installation
work is done, consult these drawings and the In

tory, it is advisable to review all adjustments before
placing the breaker in service, as itis possible that
some of the adjustments may have changed slightly

struction Book for the "Metal-clad Switcheear"

breaker during these adjustment checks. Bleetrical

GEI-25390.

operation should not be attempted until the breaker
has been operated manually through its complete
stroke and all adjustments checked.

PRECAUTIONS
Before ma

9, the following

precautions should

during shipment and instaUation. A maintenance
operating of the operating rods,

slide the shaft free of the rodtobe adjusted. Loosen
the check nut on the operating rod adjusting screw

and shorten the screw to increase the primary con

tact wipe or lengthen the screwto decrease the pri

ADJUSTMENTS

Although the breaker has been completely as

sembled, adjusted, and thoroug^y tested at the fac

mary contact mpe (1/2 turn of the eyebolt gives
approximately 5/64" change in the wipe). Replace
the check nut, shaft, cotter pin, and close the
breaker to check the adjustment.

j_a

i/« TO m

I/Tstfi
S3
&

413
40

o
M

SI
1. Csil
2. Care

6. Arcing Contact
7. Arcing Contact

3. Arc ftnuicr

8. Secondary Cbntact

4. Shield

5. Inmlation

Fig. 3

9. Arcing Blade
10. Booster l\ibe

Primary Contact MIpe, 1200 Anp

11. Contact Support
12. Shield
13. Front Bushing
14. Contact Spring
15. Operating Bod

16. Betainer

17.
18.
19.
20.

Prisuiry Contact Finger
Primary Cbntact Bleck
Primary Blade
Secondary Contact

Fig. 4 . Primary Contact Wipe, 2000 Anp

GSI~23961B

Magne'blast Air Circuit Breakers

INTBRMBDIATE CONTACTS (See Figure 5)
Close the breaker with the manual operating
mechanism until the Intermediate contacts (20) first

touch. The gap between the primary contact fingers

(17) and the movable primary contact block (18)
should be 5/16" to 1/2" on the 600, 1200 and 2000

ampere sizes. This dimension has been set at the

factory and no adjustment is provided. K enough
material has been eroded away from the contacts
to make this clearance too small, the contacts
should be replaced.

ARCING CONTACTS (See Figures 6 & 7)
Fig. S

Prinary Contact Cap

Close the breaker wiUi the manual operating
mechanism until the arcing contacts (6 &7) ]u^
touch. The gap at the intermediate contacts (8 &20}
should be 3/8"to 1/2" on the 600 and 1200 am
pere breakers, and 15/32" to 19/32" on the 2000

ampere breakers. The arcingcontacts have been set

in the factory, and no adjustment is provided. If

enough material has been eroded from the contacts

to make this clearance too small, the contacts
should be replaced.

CONTACT GAP (See Figure 8)
Withthe breaker tripped from the closed posi
tion, the gap between the primary contacts (1 and 2)

Fig. 6

Secondary Contact Gap, 1200 Asp

1. Stationary Primary Contact
1. Coil
2. Core

11. Cbntact Support

3. Arc Runner

13. Front Bushing
24. Contact Spring

12. Shield

4. Shield
5> Insulation

6.
7.
8.
9.

2. Movable Primary Contoet
3. Arcing Blade

Arcing Contact
Arcing Contact
Secortdary Contact
Arcing Blade

10. Booster Tube

' Fig. 8

Contact Gap, Breaker Tripped

15. Operating Rod
16. Retainer

17. Priaory Contact Finger
18. Primary Contact Block
19. Prlnary Blade

20. Secondary Contact

Secondary Contact Gap, 2eoO Anp

should be 3-3/8"+ 1/8" -1/16". To chaise this g^,

loosen set screws (Part Z) Fig. 9 holding the com
bination opening spring and guide-buffer stop (14),
and then screw the guide-stop (14)Into or out of the
plate which holds it. Turnlngtbe slop out toward the
front of the mechanism increases the primary gap.
Note: A change in this adjustment may require a
change in the'"Plunger Clearance" described later.

Magne-bjast Air Circuit Breakera

»*!ar

CiTO

E§9

1. Otver
3. Set Sere*

13. BottoM Plate

3. Crank

14. Guide Stop

12. Anoature

4. buffer
5. Link
6. CLesing Boiler
7. Prop
8. Prop Spi'tng
9. Cloeing Cbll
10. Plunger
11. Weaber

Fig. 9

15. Opening l^rioga
16. Taaher
17. Stud
IB. Crovn Nut

19. Trip Cbll

20. Trip Cbll
Amature

21. Stop

22.
23.
24.
35.
26.
37.

Trip Cbil Support
Lateh Spring
Latch

Yoke

Trip Boiler
Stop Bolt

38. NUt
39. Set Screea
30. Shield
31.

Spacera

S3. (kiide Stud and Mkit

Left View of MS-IO Necfianin

OEI-230S1E

GB1'*23981B Magne'blast Air Circuit Breakers

-ilf'

1.
2.
3.
4.
5.

Caver
Set Screw
Craeic
Buffer
Utik

6. Cleting Boiler
7. Prep

S> Prep Spring
9. Qoaing Cbil
10. Plunger
11. Vaaher

Fig. 10
10

12.
13.
14.
15.
16.
17.
18.
19.
20.
21.

Aniatura

Spacer*
Support
Guide Stop

Opening fringe
Washer
Stud
Crown Nut

Trip Ceil
Trip Coil
Aneature

^31

22. Step
23. Trip Cbil

24.
25.
26.
27.
28.
29.
30.
31.

Support
Latch Spring
Latch

Yoke

Trip Boiler
Step Bolt
Nut

Pin
Set Screws

Left Side View of N3>|0A Medianlaa

Magne-blast Air Circuit Breakers GBI-2S981E
14

i WIPEOR
MORE

MO TO

ECTI
OTOjOM

1. OiMr

10. PliBiEer

3. Set Screw
S. Crack
4. aiffer

11. Satber
12. ARMture

5. Unk

S. aosinE Seller
7. PMO
8. Pfop Sprles

9. OoOlni Ceil

19. Trip Cbil
20. Trip Coll Aniature
21. Stop

13. Bettoa Plate

14. GUltie Step
15. Opening fringe

22. Trip Coll support
23. Latch S^prlng
24. Latch
25. Yoke

16. Veiher
17. Stud
18. Crean Nut

27. Stop Bolt

Fl9> II

Loft SIda VioH of HS-108 Necbeaiss

26. Trip Boiler

28. Nut
29. Pin
30. Polo Piece

31. Croore Pina
32. Sleeve
33. Set Screve
34. Cover

35. Specer*
36. OUlde Stud and Nut

GEI~23961B Magne-blast Air Circuit Breakers

D
'^ssi»

c.
3
IOnr and KS-IOBZ Noctianlsaa
12

Magne-Uast Air Circuit Breakers

GBI-23961E

&>
lA

1. Nilt
2. Screw

6> Termiiuil
7. Cbntacts

3. Support
4. Sjpringer

9. Plunger Bod

5. Sfetoiner

10. Switch Base

Fig. 13

8> Araature

Cut-off Switch (HS-IOB-i)

i.
2,
3.
4.
S.
6.

Armature
Frone

Shims
Base

Switch
Switch Armature

Fig. IV

7.
8.
9.
10.
11.

Gmtaets
Terminals

Spring

Screw
Arm
12. Bailer

Cut-off Switch (MS-lOA)

•

LATCH WIPE (Bee Figures, 9, 10, 11,12)
The wipe of the latch(24)on the trip roller (20)

bolts can be run up or down to change the at-rest
position of tee MS-10 Mechanism^

®>
from a3/16"
1/4'. This can be determined
by be
potting
nini to
of

CUT-OFF SWITCH (See Figure IS)

tind» ^ head oftte stop bolt(2l) located near the

Figure 15, proceed as follows:

(XBase on the latch (24), closing the breaker part
m.v, a^tripp^, to adjun, add, or remove washers

t of the latch on the trip coil frame (22).

^ PROP CLEARANCE (See Figures, 9,10,11, 12)
*be breaker is closed as far as possible

withthe manual operating mechanism,the clearance
of the pin throu^ the closing roller (6)(numbers
W electrically,
should be .010
^1/'. Whenthe J®®'
breakeris closed
(cutto
offswitch blocked opento keep plunger in elevated
p(»itton)the clearance over the prop should be

To adjust for the clearance of 1/3F' shown in

1. Close tee breaker uslngthemaodtogperating
mechanlsib (leaving the mf^^^^verating
mechanism in place).

' T S'

2. Pin Figure 9 is resting on prop (7).
FINAL INSPECTION
1. For ease in reviewing the adjustments, the
following are recapitulated.

.030-.09V. This can be adjusted by dripping the
closing coil (9) and screwing the plunger-tm (10)

a. Wipe of primary contacts, 1/4" to 3/B".

screws (20) are used to lock the plunger rod in po
sition in the armature. If the rod adjustment is
cbugedfthe rod must be spotted in the correct posltion ^ tee set screws replaced. Spacers Ol)

b. Gap between primary contact block and
fingers, with the Intermediate contacts

into or oiAof the armature (12). Note: Two set

should be added or removed to keep the space be
tween the plunger (10) and armature (12) fuU.

LATCH CLEARANCE (See Figures 9, 10,11, 12)
.. (26) with thebetween
tripshould
latch be
(24)
and
roller
breakerthe
open
1/3F'
to 1/10*. This adjustment can be "i*"*" by

of stop bolt (27) inteefront of the mechanismframe*
near the bottom. The lock nut (28) should be fast
ened securely if any adjustment has been made.

PLUNGER CLEARANCE (See Figures 9,10,11,12)
.
the bre^r In the open position, there
shottldte
l/ff'to
1/4" clearance betweenthe plunger

(10) and the closing'roller (6). To change
clearance,tee nuts (32) on the armature plate guide

Just touchbig^ 5/lG"to 1/2".

c. Intermediate cmtact gap, with the arcing

contacts Just touching, 3/B' to 1/2" (for
600 and 1200 Amps.), 15/32" to 19/32"
ffor 3000 Amps.).

d. Primary contact gap, 3-3/B' * 1/B'
-1/lB'.

e. Latch wipe, 3/16" to 1/4".

f. Prop clearance .Olff'to ,00(7'for manual
closing, .030' to .09(7' for electrical
closing.

g. Latch clearance, 1/32" to 1/16".
h. Plunger clearance, 1/B' to 1/*'.

i. Cut-off switch, 1/32".

aBI*2S9ai&

Magns-blast Air Circuit Breakers

1. Priiury Oitcotmects

4. Heintenance Operating Doviee

7. Box Barrier

5. US-lOB-1 Hechonia

3. Adjusting Scree

6. Uheei 'Qurmcl

Fig. 15

Maintenance Operating Device

2. Check all nuts, bolts, screvs, and cotter
pins to make certain that they are properly
tightened.

3. Inspect all wiring and make certain that no

damage was donedurlnglnstallation. Check
all terminals, screws, and connections and
test the circuit lor possible short circuits

or ground.
4. Position the maintenance operating device

(4) Pl^re 15 under the solenoid arma"
ture and push down on the handle to close

the breaker. If difficulty is experienced In

closing the breaker, the clearance over the
prop can be Increased by moving the set
screw (3) In toward the mechanism. With a
screw driver, rotate the prop from iindler
the closing roller pin with the maintenance

operating device handle pushed all the way

down, and then raise the handle to open
the breaker. (CAUTION; Iteep the fingers

clear ot the linkage because accidewaT

tripping or 'fi&t aiowment couldymy se*

vert inlurvl. Operate in this cvcte td sioiT

close andslow open operation several times,

making certain that all parts are working
freely.

S. Check the closed circuit operating voltage

for both closing and tripping range specified

' below.

STANDARD CLOSING &TRIPPING VOLTAGES
Nominal

Voltages •

Closing
Range

Tripping

' Range

125 V.DC

80-130 V.DC

70-140 V.DC

250 V.DC

180-360 V.DC

230 V.AC

190-230 V.AC

140-280 V.DC
190-2S0 V.AC

Copper-oxide rectifiers are used to supply di
rect current to closing solenoid when the closing

voltage source is 230 Volts AC.

When all the foregoing inspection details have

been checked, the brealmr may. be safely placed in
service.

Magne-blast Air Circuit Breakers GEI-23981E

^""n'n B B
n*mjJjh

1. Ball Cbntocts

12. Lower Arc Amner

2. Rear Gbihing

IS. G>re

3* Tliunfa Screw

19. Pole Piece

e< Hbmtle

5.
6.
7.
fi>
9.

s
S
>1

20. Uyealex

Box Barrier
Hyceiex
Arc Qwte
InMilation
Ziuulatlan

21. Core

22. Lower Blow
Out Coil

23. Lower Arc Rmner
24. Wheel Channel

10. Bole Piece
11. Core

25. Front Ihishing
26. Shaft

13. tapper Blow

37, Coupling

Out Coil

28. Mjt

13. Upper Arc Rinnar
14. Insulation

29. Vertical Barrier
30. Insulation

is. Pole Piece
15. Lower Blow Out Coil

Flj* 16

31. Contact Support
32. Horizontal Barrier

33. Support

34. Operating Rod
35. Retainer
36. Shield

37. Contact Spring
38. Primary Finger
39. Spacer

40. Primary Cbntact Ana

41. Secondary Contact
42. Arcing Cbntact Blade
43. Shield
44. Booater Tube

45. Support
46. Bade Plate

47. Booster blinder
48. Spacer
49. Frame

Atf-5>I68 Breaker Cross Section

GBI~23Q61E Ma^e-blast Air Circuit breakers

1> Secondary Ciupiert
3. Opening Spring

5. Latch C3iedcing Switch

9. Cioaing Coil

3. Trip Q>ii

6. Ojt Off Saitch
7. Linka

4. Trip Coil Arnature

10. Cioaing Boiler

8. Prop

11. Pin

fifl. J7

Frame

Right Side View of HS-IOB-I Hechanlsa

PRINCIPLES OF OPERATION
K,
W/themagne-bUst
breator utilizes the magnetic
forces producedcircuit
bvthe
load current through the blov-out colls (12 18 221

of links (7) fastened to the operating crank. This

^ion rotates the crank and closes the breaker con

to i^crru^ the arc. These magnetic forces! to

tacts.

cyl^r (47) Md pirton (44),

After the armature and linkage have reached
^ endoftheir travel, the prop (8) rotates into positiM un^r each endolthepin (ll)through the roller
U") and the mechanism is in the closed position.
The solenoid coll is de^energized by a relAy vhich
is actuated by the cut-off switch (6)at the end of the
armature stroke, and the armature is returned by

gether with the air stream supplied bv the hnnktet-

the ire fr^Jhe

^clngconUrtsout ^ong the diverging arc runners
Jj ?7^
Interleaving
arc chute
tapered
fins that project
alternately
from(7),
theThe
two

opposite inner surfaces of the chute deflect the arc
into a ^adually deepening serpentine path. This
lengthening and consequent cooling action rapldlv

gravity to its original position.

Increases the electrical resistance of the arc to
under load or short circuit conditions, the otwitae
spr^ Mttoswingthe contact arais(4o, 42)downwari^ parting first the primary contacts, the Inter

On an opening operation, the solenoid mecha
nism functions as follows. The trip coll (3) is enMgtoed, the trip armature (4) forces the latch off
04 the roUer causing the Unk^ to collapse which

So
^ thenwhere
tran^erred
to the arc runners and
into the chute
It is interrupted.

cranks tod open the contacts. During the opening

caw Interruption. When the breaker is trlooed

mediate contacts and finally the arcing contacts

..u,

removable box barrier (5) encases each
Interrupting unUs and provid-

to gromkU^

phases and from each phase
solenoid mechanism

Srll-o

uT 9^®

follows: The sole-

energized,
the armature
is
plunger
rod threaded
Into the

armature raises the roller (10) carried by the set

allows the opening springs (2) to rotate the main

stroke, the auxiUaiy switch contacts open and in

terrupt the trip coil current. After tha breaker Is
open, the mechanism linkage returns to its normal
position, and a spring resets the trip latch.

In case the trip coil is energized while the
^ clMlng,
the trip plunger
forces the
latch
m the trip
roller allowing
ttie mechanism
iiniwitp
to collapse and the breaker to reopen. The armature completes its closing stroke, however, tod the

Is de-energized aslnthe normal closing opera-

Magne-blast Air Circuit Breakers GEI-23fl6lE

MAINTENANCE
Dependable service and safety of power distri
bution equipment is based on unfailing performance

"Replacement of Parted'.

it is recommended thatadefinite schedule be set up

ARC CHUTE

of the circuit breaker. To maintain such service,
and adheredtoforthe purpose e

Rear Bushing AsseBbly, 1200 Aap

Fig. 20

breaker111 the metal clad unit notingUthe ball coaUcts are making contact around their periphery
Readjust the position erf the bushings untflfuU contact Is made on the ball contacts.

OTATIONARY ARCING itSECONDARYCONTACTS
(See Figure 19)

Stationaryarcing (7) andsecondary(9) contacts

are made of arc resisting material andlittle erosion
CM be e^cted on interruption of load currents
When high currentsarelnterruptcd,burnlng may be
severe enough that replacement of these contacts is
Mcessary. To remove secondary tod arcing con
tacts, proceed as follovs:

9. Cap

14. Arcing Blade
15. Support
16. Booater Cylinder

Moving Contact Aaseably, 1200 Asp

suIatiM (18) is in its proper place, blow-out coll
insulatloo has not been damaged,and all screws are

ti^t.

PRIMARY, SECONDARY, AND ARCINO

CONTACTS (See Figuie 20)

To replace primary, secondary, or arcing

contacts on the movable contact arm. proceed as
follows:

1. Open the breaker.

2. Remove the arc chutes as explained under

1. Remove primary lingers as explained under
"Stationary Primary Contacts'^

"Arc Chute Removal".

S. Remove horizontal and vertical tnvitiaHng

(12>,aiidlock-

3. Removebolts holding lowerarcrunner sec
tion (6) and contact support (11) together.
4. Contact support (11) caa now be removed
The contact support willhave to be replaced

barriers around bushings.

4. Remove cotter pin In one end of the shaft
through the top end of the operating rods.

5. Slide the shaft free ofthe rod to be adjusted,
6. Remove cotter ptn (12) at pivot.

11 it is desired to replace the secondarv

7. Remove the bolt, spring and thimbles (19)

5. H^eplacing arcing conUct (7) necessitates

washers between the arcing cmtact blade

contact (9),

the replacement of the lower blow-out coll
and arc runner section (S).

To assemble the rear bushing assembly re
verse the above procedure making certain thi in-

at the pivot being careful not to lose the

and the primary contact arm.

8. Iteplacement erf either arcing contact blade
(14), or secondary contact castlu (7) and
booster tube (18) or primary c^act arm
(0) Is now possible.

QBI*499S1K

Magne-blast Air Circuit Breakers

1. Handles

7. Pin

i. Opening ^ring

13. Trip Coil Armature

B. Holier
9. Washer

14. Trip Cbil Support

3. Indicator
4. Counter

10. Trip Cbil

5. Auxiliary Switch

16. Cut Oft Switch

11. Lat^ Checking Switch

6. Link

13. Trip Interlock

17. Liric
18. Frame

Fig. 21

15. Latch

Front View of HS-IOS-l HechanUm

Reassemble moving contact assembly in re

verse'order explained above. Make certain that aU

1. Make certain the breaker is open.

cotter pins are replaced. Pressure on the pivot

2. Remove pin (?) through yoke. (17),

balance the force requlredtomovethe contact arm

3. Pull links forward and extract pin through

Joint shonld be checked by measurl^ with a spring
This torque should be between 40 and 60 pound
lacbes.

TRIP A.ND CLOSING ROLLERS (See Figure 21)
For lubricating the solenoid mechanism, U is
often necessarytoremove the trip and closing roll
ers, Proceed as follows;

trip roller (8) by pusbl^ it tluough bom
in which pin (7) rested.

4. Trip roller (8) can now be removed,

6. Remove the pin throu^ the closing roller
and extract the closing roller.

Reassemble the linkage In the reverse order.

Magne-blut Air Circuit Breakers

GEr-23B81E

RENEWAL PARTS
n Is recommended
sufficientrencml
parts
be carried
in stock to that
enable
the prompt repUeement of any worn, broken, or damaged parts A
stock ofsuch parts minimizes serrtco interruptions
CMsed by breakdowns, and saves time and expense
when continuous operatlcm is a primary considera
tion, more renewal parts should be carried, the
amount depending uponthe severity of the service
and the time required to secure replacement.
A complete list of renewal parts is contained

IntheRenewal Parts Bulletins, Those parts subject
to wear in ordinary operation, and to damage or

brcakaffi due to possible abnormal conditions, are

marked as recommended renewal parts.

ORDERING INSTRUCTIONS
When ordering renewal parts, address the
nearest General Electric Sales Office, specify the

quantity required, the catalog number from the
Renewal Parts BuUetin and the nameplate dato.

APPENDIX
Accessories usedonthe AM-5-100, AM-5-150

and AM-5-250 Breakers are as iollows:

LATCH-CHECMNG SWITCH (See Figure 32)
A latch-checking switch Is ussd to insure that

the mechanism latch has been reset aiteratripping

operation. The latch-checklng switch contarts are

connected la the control circuit in the metal clad

unit to prevent the closing coll from being energized
until the latch is reset. The wipe on the latchctocldng switch contacts should be approxlmatelv

1/lff'. Washers (3 &B) are used la adjusting the

1. Handles

5. Tsihera

2. Covers

6. Qit-off Switch

3. Sashers
4. Csntaets

7. Secondary Copiers
8. Trip Interlock

Fig. 22

Latch Checking Switch

contact wipe. By placing washers at (5) from (3)
will increase the contact wipe.

AUXXUARY SWITCH LINKAGE (See Figure 23)
The auxiliary switch linkage is used to actuate
an auxiliary switch mounted on the metal clad unit.
Link (3) la connected to a crank pin of the mecha

nism at the same point as the mechanism auxiliary

switch link (5). The distance from the center of the

front bushing to the inside edge of the fork should

' be 12" when the breaker is in the open posttton,

Eyebclt (2) can be turned to give this adjustment.

Fork

2. Adjuating Eyebolt
3. Link
4. Shaft

6. Front Bushing
7. Dandles

8. Auxiliary Switch
9. Terminal Beard

5. Auxiliary SV Link

Fig. 23

Auxiliary Switch Linkage

GBl'23Bats Magne-liUst Air Circuit Breakers

iwppeo
posmoN

WIPE

LATCHED ,

POSITION ^TO

!• ttvar

3. Pstentiia Trip
Q>U

9. Pin
-U. Hut

tl. Stop Bblt

3. Qraiik

4. Trip Cbtl ArMture
5. Mit

e. Qsupliitu

7. latcfi and Link

6. Trip Shaft

17. Sprins
18. Pin
19. Pin

13. Fkaae
U. Pin

30. Nut

14. Trip i^il Anutute

n . Salt

btenaion

15. currant Trip Cbila
U. Amatate

Fig. 2 Frane
7. Qiide Stop

2. Front Broaker ButhlnE
3. Cover

IS. Stud
19, Washers

4. Crank

5. Buffers

iO. Frane
t

ad
•*'
«••
444 ®-W.<»»'«
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fo.

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Peitlttfid 18,Ortomi.. 3737HW.29lhAY«.
Rlchund 34, Vo.
.. 1403 hgram Ay*.
Si. laah 10, Mo
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443CMarSl.

335 5, Main St.
90 Slot. St.

Albwomr^., N.M*»... • .333 third St, S.W.

Al.iendri^lo,
.... 720 Murray St.
AMmilOYvii, Po.,....... . ..1014 HMlllon St.

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Tutarg and Fulton Si.

14OS tecint $1.
Smlihnrtd SI.

Orond Rapid, 2,Midi. UIMoiuym Ay.,RW.
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Cr.MYin,, S.C
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410 A>yl«in Si.

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.....1 So. St. Qelr Sr.
... .54 M. darriion Si.

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40 S. Third Si.

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....II8I1V. KrdSI.
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.. 1801 R Idmor St.
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apparatus sales offices

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Mobil. 13, Alo... •. . • • 54 SI.JoMph Si.
Monteeai*ry A Ala.
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Oakland 12, CbUf...

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WoA.

421 W.doHi 51.

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5S4 feyoilna* St.
31 R Sixth St..

700 E. Pranltin St.
SSOBMolnSl.

Reonoko 14, Va... .V30-924 S. Joflnrwn St.
Oodiodif 4, R Y............... 69 B. Ayo.
Rockford, O.
.. . .%.VIOS.Piid St.
Rotond, VI.
3814 ConlorSl.
*»<»o«>«nlo lA CbSt.. ... .424 Pom Bide.
SoglnaYY, Mich.. . .. . .501 Buftngor lldg.
Si tool, 2, Mo... . .
112 R Poortk St.
Sell lake Oly 9, Uiob.
200 S. Moln St.
Son Anionie 5, Tono,.. ,..3I0S. Sl.Mor/, St.
Son Mogo t.Celif..... . 1240 SoYwoh Ay«.
Son Prondico 4, CdBI.. .235 Moitt0ani.ry Sa
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SorlhBond 1,k>d.. -112 W, iadoiYonMvd.
Spokono 8, Woth.
S. 142 Pod Si.
Springhold, U,..,., .......407 A Adoat, Si,
SprkigfloU3, Mou.
Stockton, CoBR.
..11 Sp. Bon3eaqYki St.
SyrecoMS, R v....
.. .113 A SoRna Sr.
Tocem I, Wodb. . 1202Woihkigtea
BMg.

Yonipa A floI20S Monti A SI.
Toledo 4. Ohio.... >>... .420 Modboa Ayo.
Tronton 8, M. 3.
.....214 AHdnovor SA
Tuba 3, Oklo..
Tuciofi, Aril.,
Ulko A R Y.

n i; • • ill?'®
Avn.
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4S0RBoiton
SInlh Avn.

•2SS GaaM.0 SI,

!it?.®^?'^j''>:^"-»~7^-l4i'h"sr,Rw:
Woln,^ 89,COWA
Ill w. Main SA
Wotscin.Imm...,

204 W, 48i St.

Whn.1ing, W.Vo...
Widdto A Kon.....
W«noindon,RC..

. ..40 PounoMih St.
300 A fird SI.
list. Main St.

Wwiotthon, Wadt. . 328 R W.notcbc. Avo.

WIMngion 98, Onf.. .. . .1334 R Morkot St.
Worcodar 8, Mou..
....507 3*011, St.
- .54 R Horriwo Si.
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R.SI

general® ELECTRIC
SvponMn C*hlS9«IO

INSTRUCTIONS
ANfJ

RENEWAL PARTS

GEI-50143F

SUPERSEDES GEi • 50143E

S5 S

F"o 'R 1f � V. c_'\ "'Q. c._ \.'(. \ 'T�
�Z)".30-S7A, "rR, )fQ. 7c, �/\(..V, 13t-\.� ....YA.

c._

STORED ENERGY OPERATOR
Types

Ml -11
ML- 11A
ML-118
ML-11(
Ml-110

s.·--

CONTENTS
PAGE
INTRODUCTION ............... 3
INSTALLATION•••••.•••.•••••• 3
DESCRIPTION OF
OPERATION•.•••••••••••• 3
ADJUSTMENTS................ 4
INSPECTION AND TFST•••• 8
MAINTENANCE............... 8
PERIODIC INSPECTION•••• 8
LUBRICATION ••••••••.••••••• 8
. RENEWAL PARTS ••••••••••• 12

�--------------------------------------------------------------------------HIGH VOLTAGE SWITCHGEAR DEPARTMENT

GENERAL. ELECTRIC
PHILADELPHIA, PA.

CD
e

5-OUTPUT CRANK
ROLLER

4-SPRIN6 ARMS

2-GEAR REDUCTION

12-CONNECTING LINKS TO
BREAKER MECHANISM

UNIT

5-STOP LATCH

6-SLIP
CLUTCH

TRAVEL

7-CUTOFF.
SWITCH

DRIVE

10-RELEASE

CHAIN

-—^

ROLLER

13-MANUAL CHARGING
HANDLE

l-GEAR MOTOR (^)

8-RELEASE
SOLENOID

3-CmSIN6 SPRINGS IN
CHARGED POSITION

(52X)

II-KICK-OFF SPRING

14-MANUAL RELEASE

9-RELEASE
LATCH

Fig.

Exploded Schenaflc of Stored Energy Operator

Cover
/'

(8028S80}

STORED-ENERGY

OPERATOR

FOR

IWAGNE-BLAST

CIRCUIT BREAKER

INTRODUCTION
The new charged-springstored-energy
mechanism will close and latch magneblast breakers with momentaiy current

ratings 19 to and including 70,000 amperes
in voltages from 4.16 kv to 13.8 kv and in
tnterr«9tlng ratings from 150 mva to 750
mva, inclusive. The merating force for
the mechanism is sqqjilted by a high speed

energy fram the motor is stored in power
ful springs which are cajudile of closing
the circuit breaker at its required speed
under all conditions. Onfy after the mech
anism is fully charged can it be released

1/2 hp gear motor. See Fig. 1. The

mechanism, the motor immediately re
charges the wrings for another closing
operation. The spring charging time on
approximately seven seconds and the fast
circuit breaker closing time provides
ample time margin for all normal duty

cycles.

close the tnreaker.

As soon as the

circuit breaker has been closed by the

INSTALLATION

The following instructions explain Ihe
necessary steps to be taken buore the
mechanism Is placed in the metal-clad unit.
Reference should also t>e made to the con

il). Fig. 3used to retain the block nlate

b. Primary contact gap.

2), Fig. 3. Move blacking plate (2), ng. 3

(Refer to

Magne-Blast Circuit Breaker book
for description.)

approx. 1-1/2") from right to left (facing

mechanism) untU the riAt flanrc is against

fC. Prop clearance. (Page 4 this book)

nection diagram as well as the magne-blast

the spring frame i^ris^t (3), Hg. 2. Re

breaker instruction book that is furnished

lease the closing springs against this block

ing plate by pushing the manual release

After these adjustments have been
checked the eprings can be unblocked. To

button (3), Fig. 3. THE SPRINGSARENOW
BLOCKED. The closmg spring wiu now be

unblock the springs, manually charge the
closing springs as described in "MANUAL

confined in this position and the gear motor,
reduction unit, mechanism linlo^ and
breaker contacts are free to move, and the

CHARGING" operation. Move the BLOCK

with each breaker.*
"DO NOT WORK ON EITHER THE
BREAKER OR THE MECHANISM UNIJESS
THE CLOSING SPRINGS ARE BLOCKED
AND THE OPENING SPRINGS HAVE BEEN
TRIPPED OPEN OR MECHANICALLY

BLOCKED. THIS BfEASIlRE IS REQUIRED
TO PREVENT ACCIDENTAL CLOSING OR
TRIPPING."

At installation of the equipment add a
10 amp fuse In the closing and charging

circuit. When the equipment is finally in

stalled, change the fuse to the size recom

mendedon the connectiondiagram.

Charge the breaker closing springs

manually using the manual charging nanring arms (4) to the fuUy
charged position. When the closingsprings

springs are again charged.

compress the closing springs (3) throuah

reads

The use of the ratchet wrrach profor maximum safety in the event that

warning.

In this event, the motor drive

takes over a^in and continues to charge the

switch (7) starts the motor (13) and the
BIANUAL CHARGING

positkm the output crank roller (IS) is

(Ref. Fig. 1)

(5), and the sem^^ihore reads "CHiwGED".

Closing the breaker may be accom
plished by manual operation of the mech
anism if control voltage is lost. The

ELECTRICAL RELEASE

closing springs may be charged mannally

(Ref. Fig. 1)

hy using a standard l"soCketandastam£urd

When the release solenoid (8) is en
ergized, its action rotates release latch (9)

semaphore

Immediately ipcn its release the cnt-tm

(3) are rally compressed, a cut-oa switch
(7) de-energizes the motor (1). In this

mechanically st^ed against stm latch

until the

ratchet handle. Attach the handle (131tothe

MANUAL RELEASE

(Ref. Fig. 1)
The closing speed of the breaker is
independent of the method of' charging
die qi>rlngs or release of the controlmechanism, and the breaker closes at the same
speed for a manual release as it does
for an electrical release. Tb manually
release the closing springs and close the
breaker, press manual release plunger

(14).

This actuates release latch (9)

ri^t side of the motor sprocket ana using

and the linkage operation is the same as
stated in the "Electrical Rdease" des

a pumping action rotate the handle counter

cription.

ni«M ImtrucMom do not pvfport to covtr all
or vonntiont in aquipmont nor to pramdu (or ovoiy petsiUo
eonflngoiKy to bo mot In ceimoetlon with Inflation, oporathn or mainlonaneo. Should (urthor bilormation bo dodrod

or thouU porlleuler prob'offlf erito which ore not covered mKkionlly tor Iho puichator'c pwpoM*, tfio snallor ihould

bo referred to the Gitneraf Bodrk Company.

GEI-50143

Stored-Bnerg7 Operator l^pe ML-11

ADJUSTMENTS
Adjuatments sbould be checked during
periodic inspections and whenever it be-comes necessary to repair or replace parts

. that have become worn or defective while
In service.
"DO NOT

WORK ON EITHER THE

BREAKER OR THE MECHANISM UNLESS
TEE CLOSING SPRINGS ARE BLOCKED
AND THE OPENING SPRINGS HAVE BEEN

TRIPPED

OPEN

MECHANICALLY

BLOCKED. THIS MEASURE IS REQUIRSO
TO PREVENT ACCIDENTAL CLOSING OR
TRIPPING."

!• OKrglng Eindle

2- Spring Blocking

Plate Seitch
3- Fraffle

4. Opening Spring
5. Motor Shiaa
6. Chain

7. MoiBiting Bolts
8. Switch Bracket
9. Switch Actuator

TRIP LATCH CLEARANCE (Ref. Fig. 4)
With the breaker in the tripped posi
tion, check the clearance between the trip

latca (4) and trip,roller (6). Itshould mea

sure i/S2" to 1/16". This shoi;^ be mea
sured with the closing springs ga^d, and
alter the breaker has been tripped out.
TRIP LATCH WIPE (Ref. Fig. 4)

Paddle

The wipe of the trip latch (4) on the

trip roller (6) should be from 3/16" to

1/4".

This can be measured by putting a

r^.wa

film of grease on the latch (4), closing the
breaker part way, and tripping. The mecha
nism has the proper trip latch wipe when
the latch rests against the stop pin (5). No

-•fetjfa-.rfvtsr.a

adjustment is provided and a visual in
spection is usually all that is required.

L «r

PROP CLEARANCE (Ref. Fig. 4)
All Designs

Block the closing springs (Using the
manual charging handle (1), Pig. 2 rotate

the prop pin (8) to a position over the prc^
(10) as far as posslUe.
ML-11 Design
Measure this clearance with a feeler
Skge.,

The

clearance should measure

between .040" to .070" for the AM-4.16-

150- 250; AM-7.2-250; AM-13.8-250-500

breakers and .060" to .100"for theAM-7.25C0 and AM-13.8-750 breakers.

In con

junction with this measurement, when the
1- Blocking Plate Setainlng
2. Blocking Plate
Beleeae Button

4. Seaiaphore

breaker is in the imhinrkaH position, manu
ally close the breaker and measure the
distance the prop ptn comes to rest over

the prop. (NOTE: It is possible that In
some breakers it will rest on the prop).

Rotate the prop pin back over the props the
distance measured •» 1/16". At this point
the breaker must trip both manually and
electrically.

-amm

ML-llA, IXB and IIC Design
The clearance for all rated breakers

^ould be 1/16" minimum measured when

the springs are blocked. (This clearance
may measure 3/8" over the prop pin when

the mechanism is

unblocked ""rf fully

closed).

On All Designs
On ail designs the allowable difference

between sides of the prq) pin (8) measured

from the t(g) of the prop (10) to the under

side of the prop pin (8) is 1/16". If ad

justment is required remove the bolts
holding the bearing blocks (28) and add or
remove shims (29) as required. Loosen

Stored-Bnergy Operator Type ML-11 GBI-50143

!• Itoin Operating Shaft
2. Hain Crank

3.
4.
5.
6.

Trip
Trip
Trip
Trip

Shaft
Latch
Latch Stop
Boiler

7. Position Indicator

B. Closing Pin
9. Cotmter

13.
14.
15.
16.
17.
IB.
19.
30.
21.

Adjusting Niit
Adjusting Stud
Opening Spring Housing
Opening Spring, Inner
Opening Spring, Outer
Main Spring Shaft
Spring Take Asseobly
Closing Springs
Haintenanee Spring Blocking Plate

10. Prop

22. Gear Eeduetion Unit

11. Qevis
12. Check Nut

23. (kitput Crank

24. Spring Compression Arm

Fig. 4

Cross Section of HL-II Kechanii

25. Step Latdi
26. Gear Motor
27. Close Latch

38. Bearing Block
29. Pillar Bledc Shims
30. Latch Beset Boiler
31. Output Roller
32.
33.
34.
35.

BeUer
Csnoe Link
Banana Link
Gear Bn Shim

GEI-50143 Stored-Energy Operator Type ML-11

|-FIG.4B

^=^24
25

1-FIG.4B
Fia- 1A
1> Release Latch

2. Release Latch Roller

3' Adjuatnent Bolt
4. Auxiliary Switch
(Inboard)

5. Auxiliary Switch
(Outboard)
4. Swit^ Actuator Paddle
7. Switch Bracket Bolts
fi. Switch Bracket

u«'
EACHaoe
MM.

9. Pin

10. Switch Lock ?h]t
11. Uanuol Release Button

12. Reset Spring

13. Bolt

Fig. HA and 4B

bolts and adjust only one bearing block

(29) at a time.

The addition of a 1/64"

shim will decrease the clearance approxi

mately .010". Conver8elyremovingal/64"
shim will Increase the clearance approxi
mately .010".

RELEASE LATCH CUIARANCE (Ref. Fig.6)
If the latch (1) fails to reset, check to
see that the latch reset roller (2) has a

clearance between the reset latch (1) top
surface and the t>ottom of the roller (2) of

1/32" to 1/16".

No adjustment is pro

vided and a visual Inspection is all that ir.
1. Spring Release Link
2. Release Latch Pin
3. Spring Release Pin

required.

To make latch (1) respond

faster add tension to spring (12) by rotating
bolt (13) counterclockvrtse.

6. Spring Release Link Bolt
7. Lock Nut

RELEASE LATCH WIPE (Ref. Fig.

AUXILIARY SWITCHES (Ref. Pig. 5)
The auxiliary normally closed (4) in
board and normally open (5) outboard
switches are set to have bothswttchbuttons

operated together initiated by the switch

actuator pa(We(6). Theyareoperatedbythe
action of paddle (6) and are indexedwlththe

gear box crank (23) Fig. 4 toc^ieratebefore
the gear box crank roller (31) Fig. 4
comes to rest against stop latch (25)

Fig. 4.

They are adjusted and set at the

factory by applying the minimum oper
ating voltage to the motor and should re

4. Cotter Pin

5. Latch Shaft Actuator Pin

1/4". If the setting is incorrectadjustwipe
by rotating adjustment bolt (3) clockwise or
counterclockwise. Recfaeck above setting.

The wtpe between the right t(^ latch
surface edge and the center of the release
latch rpUer should be between 3/16" to

quire no additional adjustments.

They

are set properly when the crank roller

(31) Fig. 4A is resting against stop latch

(25) Fig. 4A and the "A" angle Fig. 4Aas

measured between the ou^ut cruik (23)

Fig. 4A and spring compression arm (24)

Stored-Energy Operator Type BAL-ll GEl-50143
Fig. 4A cam surface measures 00® to 94®

on the ML-11 design and 95® to 102® on the
ML-llA, ML-llB and ML-llC design.
However, U adjustment of the switches Is

required, first block the closing springs,

link (1) clockwise or counterclockwise.
Assemble and recheck.

On HL-11 deelgn

check the clearance between the latch
shaft actuator pin (5) and spring release
link pin. The clearance should measure

unscrew bolts (7) Fig. 5 and rotate com

1/32" + 1/64". No adjustment ts supplied

plete switch bracket (8) and both switches
(4 & S) about pin (9). When the bracket (8)
and switches U 5) are moved toward the

On the ML-llAandUL-llB design check the

switch actuator paddle the switches will
tmerate earlier In the charglngcycle. When
the bracket and switches are moved away

and a visible check Is all that is required.
clearance between the latch shaft actuator
fin
(5) and spring release link bolt (6).
t should measure 1/4" to 5/16". To

aiMust, rotate bolt (6).

Tighten loclmut

BLOCIGNG PLATE SWITCH (Ref. Fig. 2)
The blocklag plate switch (2) is con

nected In the motor circuit and located
such that when the closing springs are

blocked the switch opens. When the clostng

springs are not blockedthe switchts closed.

When the switch is closed there should be

an overtravel of 1/32" to 1/16" on the
switch arm.

If adjustment Is necessary

first check bolts (7) for Uf^tness, then
bend the switch actuator paddle sli^tly

from the switch actuator paddle the switches
will operate later in the closing spring

(7) and remeasure.

to give the required overtraveL

charging cycle.

FRICTION CLUTCH (Ref. Fig. 7)

DRIVE CHAIN (Ref. Pig. 2)

After the setting has been made check
to see that the switches have a minimum

of 1/16" overtravel on the switch buttons.

If not, adjust switches (4 6 S) on bracket
(8) either individually or together byloosen

The friction clutch should be tested

The chain Is set smig at the factory
and should require no additional adjust

away torque of 300 to 350 Inch-pounds on
the AM-4.16-100/150, 250, AM-7.2-250,
AM-13.8-250/500 breakers and 350 to 400

ment.
However, as Is common on cbatn
drives after numerous operations the chain
will set lower in the sprockets and show

breakers.

measure the horizontal distance be^een

with a torque-meter (X) to have a break

ing switch lock nuU UOjandmovlngswltch- Inch pounds on the AM-7.2-500 & 13.8-750

es out. Tighten switch lock nuts and recheck
adjustment. Charge the closing springs

Rest wrench (2) against frame

manually and check the operation of the

Sand apply torque to the torque meter

switches with a bell sat.

the v^ue on the torque meter dial.

Remove block

from the closing springs and close the

mechanism manually by pressing manual
release button (11). Wind up mechanism

electrically by applying minimum control
voltage (see control power range) to the
motor.

The switches should cut off and

allow the output crank (23), Fig. 4 to
coast against latch (24), Fig. 4.
mechanism

should then

and electrically.

The

manually

When the above Is fin

ished and checked the switches are adjusted
properly.

until the clutch breaks away and note

not continue to turn if the value exceeds

that as stated above.

If adjustment is

required, refer to Fig. 8, loosen 2 set

screws (1) In the hexagon bead nut (2) and
^ply clutch adjustment wrench (3) to hexa
gon head nut (2) and wrench (4) to the
square coupling (5). Tighten or loosen the
hexagon head nut (2) ai^ tighten the set
torque.

on the release latch (2).

This should

be 1/2" to 5/8" measured from the bottom
of the actuator slot to the bottom surface

of the ptn. To check this adjustment,
charge the closing springs of the breaker

Pull both

and measure

sides

distance.

together
Rotate the

sprocket 180® and measure both distances
agatn. If the difference between dlmenelons on each set of dimensions Is greater

than 5/8" add shims (7) between the motor

mounting base and the gear box base.

OUTPUT ROLLER (Fig. 4, 4A & 4B)

The output roller (31) and the spring

INTERLOCK SWITCH WIPE (Ref. Fig. 7)

ing spring release link (1) and the pin

the inside edges of the chain in the normal

' position.

screws (1) in the nut and recheck the

SPRING RELEASE (Ref. Fig. 6)
Check the clearance between the clos

signs of looseness. To check the chain,

Rotate the interlock shaft manually
clockwise to release the Interlock switch

arm (4).

7%e point at which the contacts

make can be determined with a circuit

continuity tester such as a light Indicator
or bell set. To obtain adjustment on the

compression arm (24) shoald have ^least
50% minimum engagement. The 50% en-

^gement should be taken from the center

portion of the ou^t roller (31) as shown In
Fig. 4B. This engagement shouldbe check

ed when the mechanism is In the charged

position.

To adjust to this condition add

or remove shims (35) bstween the frame

and gear reducHon unit (22).

Interlock switch (5), bend the Interlock

The breaker should

switch arm (4). The roller and crank on
the Interlock switch (5) should have 1/32"

AUXILIARY DEVICES

trip out before the closing springs dis
chuge giving a "Trip-free" operation- If
adjustment Is necessary, remove one cot
ter pin (4) and dlsaseemble link. Rotate

internq)tthe motor current with this switch
as damage to the switch will restilt.

Refer to themagne-blastcircuitbreaker inistructlon book for adjustment of all

and rotate the spring release
counterclockwise.

(3)

1/16" overtravel after final adjust

ment.

No attempt should be made to

auxiliary devices.

CONTROL POWER CHECK (Ref. Fig. 2)
Alter the mechanism has been closed

and opened slowly several times with the
maintenance closing handle (1) Fig. 2 and
the mechanism a^ustments checked as
described, the operating voltages should'

1. Torque Ueter
2. trench
3. Freae

4. Interior Switch Ara
5. Interlock Switch

S. Latch Checking Switch Arm
7. Latch Qiecking Switch

1. Set Screwe

4. trench

2. Hex Heed Nut

S. Coupling

3. Clutch Adjuitment trench

(iEI-S0143 Stored-Energy Operator l^e HL-11

be checked at the release coU, trto coU,

and motor terminals. For electrical oper
ation of the mechanism the control power
may be either an alternating or direct
corrent source.
The operating ranges
for the closing and tripping voltages are
given On the breaker namsplate. Ordin
arily. standard ranges appty which are
as follows:

Nominal

Voltage

Closing

48v d-c
125v d-c

Ran^

Mln.

Max.

34 -

SOv d-c

Mln.

28 -

60v d-c

90 - 130v d-c

70 - 140v d-c

180 - 260v d-c

140 - 280v d-c

230v a-c

190 - 250v a-c

ISO - 250v a-c

1. For ease In reviewingthe adjustments,

AND

ML-llA, ML-llB an3 ML-llC

(a) Primary contact wipe, arcing con

tact wipe, primary contact gap,

1/4" to 5/16". (Fig. 6)

(h) Auxiliary switches - 1/16" over
travel - Angle.

plunger interlock and arodlEy
(b) Trip latch clearance - 1/32" to
1/10". (Fig. 4)
(c) Trip latch wipe - 3/16" to 1/4".
(Fig. 4)
(d) Prop clearance - See prop clear

ance section. (Fig. 4)

ML-ll 02O to

940 ML-ll^ML-llBandML-llC
95" to 102". (Fig. 5)

devices - refer to mamie-blast cir

cuit breaker Instrucnon book.

be given a hl-potentlal test at 1500volts,
remove both y wearing rubber gloves andby using the

Sleeve Bearings

alcohol tn a well ventilated room; excessive

The ptns should be removed and all
old oxidized grease removed by Immersion
In clean petroleum solvent or similar
cleaner.

a small amount of G.E. Lubricant DSOHlS

collapsible tubes. It Is so packaged to
insure cleanliness and to prevent oxidation.
METHOD OF CLEANING BEARINGS

Wherever cleaning Is required, as
indicated tn the lubrication chart, the fol

ings in li^t oU and draining should follow
immediately, then apply the lubricant.

Gear Reduction Unit (Ref. Fig. 19)

to the entire surface of the bearing and ptn

Just before reassembling.

The gear reduction unit should be
removed from the frame after disconnect

Removable Seal and Open Type Ball, Roller
and Needle Bearings

The bearings should be first removed

and D50H47 are available In 1/4 pound

exposure to the fumes Is sometimes un
pleasant to personneL Washing the bear

DO NOT USE CARBCW-TETRA-

CHLORIDE. Wipe the bearing clean. Apply

breaker becomes slower.

General Electric Lubricant D50H15

in the alcohol more than a few hours. If
it Is desirable to leave the bearings Is the
alcohol for a longer time, an inhibited
alcohol such an Is used for antl-freeze
should be used. Even then the bearings
sbould be removed from the alcohol within

effects of the alcohol must be exercised

with the lubrication chart. It Is also rec

ommended that all circuit breakers be

ner) be sure the alcohol Is perfectly clean,

twen^-four hours. Esso Antl-freeze and
DuPont STerdne' are satisfactory for t^
purpose. Precautions against the tx»ie

Lubrication Chart

whenever It Is overhauled, In accordance

O tt tiecomes necessary to

from the mechwism and disassembled by
the removal of the seals or inner face .

the case of needle bearings.

They

should then be placed In a container of
clean petroleum solvent or similar cleaner.
DO NOT USE CARBON-TETRACHLORIDE.

If the grease in the bearings has become

badly oxidized, it may be necessary to ^e
alcohol (type used for thinning shellac) to
remove tt.

Ordinarily, by agitating the

ing the chain drive and motor, and blocking
the springs with the maintenance blocking
plate.
Removal of the cotter pin and washers

from the end of the shaft, and the four l»lts

holding the end bell (221) on the casting
will aUow enough of the unit to be disas

sembled for a Utorough cleaning. Remove

the pinion (211) ring gear (237) and ec
centric (210) and place them In a container

of clean petroleum solvent or similar
cleaner.

DO NOT USE CAHBON-TETRA-

CHLORIDE.

The housing and remaining

parts can usually be cleaned wtth a stiff
brush and petroleum solvent

Inspect all

gears, spacers andinternalpartsforcracks

or any si^ at unusual wear. Inspect the
oil seal rings on the shafts and the gasket
on the bell end cover to Insure a tight
fit

some cases, small metal chips may

^pear In the olL

This Is not unusual

and is to t>e expected from new gears.

Reassemble gears, spacers, etc. In

tbe opposite order of their removal and
add 2 ounces of SAE 20 or SAE 30 oil as

shown in Fig. 10.

Do not use more than

2 ounces of oil as high internal pressure

causM by tbe rotating gears will force the

oU past tbe gaskets and oU seal rings.

1, Oil Funnel

2. Oil Drain

Reassemble gear reduction unit, motor
and chain drive on mechanism. Before

applying power to the motor, check all
clearances

indicated in adjustments.

GEI-S0143 Stored-Energy Operator Typo ML-11

!• Spsmer ffrendi

i- 1* Snap-on Wrench
3. 3/4" and 7/8" Snap-or*
Wrench (Supplied With

I3.Skv Ocr. (My)
4. Spring Ccnpreeaor

5- fietaining Bing Pliers
6. Square Kut Wrench

?• Ketalning Sting Pliers
8- Eetaining Ring PJiers
9. Hex Nut Wrench

Fig. II

Tool S«t forHL-ll Stechanie

y ^S/V/iS ^ -sj^/isr -Tit,—

^6e¥£»yyg£ ys

—

:jS&.
.gg

/>sv

ir.L

fs^ggy

54// rtf// ^/%sv ui/ye/v sp/f/f*^
eccd/fyry^ Pi.^TE/s//\/
3coaff//>f6 ypoysyr/o/^y

il rc

S£.

S5 Sp^/yyet

syv/ii^

y:feLe/9se

coryTPidr-s^^
cs'-eii cc Asexi uyyysyv •sp/fy/yQS ^yfe /^4/y.c.y
ay-/p)Pdsd}.

Fig. 12

Typical Breaker Wiring DIagraa

ciosyAf^

S^.

Stored-Energr Operator Type ML-11 GEI-50143

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In tabulation below are listed parts which are recommended for stock for
normal maintenance. Other parts are listed on the following pages.
fig.no.

REF.NO.

14
14
14
14
16
16
16
16
13
18
18
20
20
20
20
20
19
19
19

108
108
108
108
109
109
109
109
119
204
207
212
216
217
218
225
239
239
239
240
240
240
241
257
257
257
279
280
281
292
292
292
292
292

•

23
23
23
23
24
23
23
23
23
23
23

/\
•

CAT. NO. FOR
ML-11

NO. PER
MECH.

Motor (48v d-c)

-6517087 G-7
-6517087 G-5

Motor (125t d-c)

Motor (250v d-c) 170113
Motor (230r a-c)
Relay ( 48v d-c)
Relay (12St d-c)

-6517087 G-6
•^517087 G-6
12BGA11H54

12HGA11H52
12HGA11H51
12HGA11H71
254D738 P-64
104A2451 P-2
265C189 P-6
258C626 P-10
21SD472 P-12
215D472 P-11
215D472 P-38
258C626 P-12
258C626 P-19
2S8C626 P-14
258C626 P-13
258C642 P-12
258C642 P-11
2S8C642 P-10
265C180 P-9
104A24S6
414A135 P-1
104A2456
9921661 P-1
104A245S
0021661 P-2
6174582 G-1
6174582 G-2
6174582 G-14
6275070 G-2
6275070 G-1

DESCRIPTION

Relay (250v d-c)

Relay (2307 a-c)
&ring Blocking Plate Switch
Clutch Spring washer
Clutch Friction Washer
Gasket

Gear Box "0^* Ring
Gear Box "O" Ring
Gear Box "O" Ring
Drain Plug Gasket
Motor Shims 1/64" Thk.
Blotor Shims 1/32" Thk.
AR
2
2
3

Motor Shims 1/16" Thk.
Pillar Block Shims 1/64" Thk.
Pillar Block Shims 1/32" Thk.

Pillar Block Shims 1/16" Thk.
Gear Box Shims

Release Latch Reset Spring (ML-llB)
Release Latch Reset ^ring iML-11 & ML-llA)

Release Latch Reset ^ring (ML-11 &21L-11A)
Motor Switch (Norm. Open)
Release Roller Spring

Motor Switch (Norm. Closed]
2^

2^
2z:s.
2^
1

Release & Trip Coils 125v d-c

_ _.

Release & Trip Coils.2507 d-c » A7 A Hds

• su

Release 6 Trip Coils 230? a-c
Release & Trip Coils 48v d-c
Trip Coil 24v d-c

Use one for Spring Release Circuit and one for Trip Circuit.
Not Shown

GEI-50143 Stored-Energy Operator Type ML-11

RENEWAL PARTS

ISsIsm"
Note: The listed terms "right" and "lett" apply when facing the mechanism end of the breaker.
ORDERINC INSTRUCTIONS

ALWAYS SPECTFY THE COMPLETE NAMEPLATB DATA OF BOTH THE BREAKER AND THE
MECHANISM.

SPECIFY THE QUANTITY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF LISTED)
AND DESCRlPnON OF EACH PART ORDERED. AND THIS BULLETIN NUMBER.

STANDARD HARDWARE, SUCH AS SCREWS, BOLTS, NUTS, WASHERS, ETC., IS NOT LISTED
IN THIS BULLETIN. SUCH ITEMS SHOULD BE PURCHASED LOCALLY.

FOR PRICES, REFER TO THE NEAREST OFRCE OF THE GENERAL ELECTRIC COMPANY.

i -

'm
Ctf

a
I w®

IV.. \ 1

s> .

4 A

•!

L. .1^

Fig. 13

Fig. 19

CJ'Wx .

'ti

Stored-Energy Operator Type ML-Il

J'.S

1'^

CAT. NO. FOR

NO. PER

ML-11

MECH.

298C604 G-4
41SA489 G-1

6192382AB P-1
281B711 G-1
258C601 P-14
258C601 P-15
236C788 G-10
258C601 G-3
6517087 G-S
6517087 G-6
6517087 G-7

DESCRIPTION

Manual Trip Assembly
Auxiliary Switoh
Operation Counter
Indicator Assembly
Shalt(4.16)
Shaft (13.8 & 7.2)
Crank Assembly
Bearing Bracket

Motor fl25v d-c)

Motor (250t d-c L 230v a-c)
Motor (48t d-c)

I2HGA11H54

Relay (48v d-c)

12HGA11H52

Relay (125v d-c)

12HGA11H51

Relay (2S0v d-c)

12HGA11H71

Relay (230v a-c)

12HQA11H56
6190421 P-8
619C421 P-4
619C421 G-3
619C421 G-4

Relay (24v d-c)
Trip Lock Rod
Trip Lock Link
Trip Lock Pin L Crank (4.16, 7.2 & 13.8-500)
Trip Lock Pin & Crank (13.8-750)

688C511 G-2

Trip Interlock Complete (4.16)

688C511 G-1
688C511 G-6
688C511 G-3
6443518 P-2

Trip Interlock Complete (13.8 6 7.2)

Trip Interlock Crank Only (4.16)
Trip Interlock Crank Only (13.8 & 7.2)
Shaft (4.16)

6443518 P-1

Shaft (l3.8 & 7.2)

8360190 P-1
215D472 P-13
802B795 G-3

Crank
Chain

802B795 G-4

2540738 P-64

Secondary Disconnect Device Complete (#14 Wire)
Secondary Disconnect Device Complete (#12 Wire)
Spring Blocking Plate Switch (N.O.)

GEI-50143

GBI-6014S Stored-Snergjr Operator

BIL-ll

eUtufd

Sutler-

AtVitw't

Fig. i7A Cooplete Opening Spring Asteably

uw/r

Ref. iHS

Vmtn
/35=

I
Vilw P

VtKW ff
h

ail

VltW G

V/CMT K
Fig. 17

Cross Section

Stored-Energy Operator T^e ML-11

REF.
NO.

CAT. NO. FOR

125

215D465 P-34
215D465 P-3S
258C635 P-11
121A7436 G-1
104A2472 G-1
421A244
82BC758 G-1
215D473 G-53
2150473 G-52
258C627 P-10
215D473 G-51
456A876 P-102
414A112 P-1
414A110 P-S
2580628 P-4
456A820
6370567 P-51
456A876 P-104
414A10S P-10
6509799
456A876 P-105
258C630 G-4
256C630 G-6
2150473 G-54
258C609 P-9
828C7S8 P-7
421A209 P-101
383A926AE P-39

125

126
127
128
129
130
132
133

1S4
135
136
137
138
139
140
141
142
143
144
145
146
146
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163

164
165
167
168
169
170
171
172
173

174
175
176
177
178
179
160
181A
182

ML-11

NO. PER
MECH.

2150473 G-55

2150473 G-56
265C189 G-1

OESCRIPTI(»(

Latch Shaft (4.16)
Latch Shaft (13.8 b 7.2)

Step Bar

Dry Bearing Assembly
Stop Bar
Spring
Latch & Pin

Link & Bushing
Link 6 Bushing
Prop Pin
Link & Bushing
Stoacer

Needle Bearing
Pin
Pin

Spring
Bushing
S^»cer
Washer

^acer

$rlng Assembly Complete
Spring Assembly Complete (13.8- 750)
Crank & Bushing
Pin
RoUer

Spacer
Pin

Crank & Bushing
Crank & Bushing
Prop

258C627 P-13
4S6A885 P-1

688C5S3 P-10

Pin
Link

258C627 P-4
4S6A876 P-19
258C627 P-11
6176109 P-168
414A112 P-8
6176109 P-174
258C627 P-12
258C630 P-7
25BC630 P-8
258C630 P-3
456A808
456A807

Bushing
Spacer
Pin
Etoacer

Needle Bearing
Spacer
Pin

Clevis
Rod

Spring Retainer

Inner Spring

Outer ^ring

2S8C630 P-4

^rlng Base

383A926AE P-1
258C630 G-3
414A109 P-8
258C630 P-5
383A926AF P-20
258C609 P-4
6190478 P-19
68BC568 P-8
0258C0611 P-15
2150473 G-57

» (1) For Std.

GEI-S0143

Plate
Buffer

Retaining Plate
Pin
Crank

Pin for End Pole
Pin for Center Pole

Opening Spring Cover (Left Hand Spring Only)
Closing Crimk & RoUer Assembly Complete

(2) For 13.8-750

A Not Shown

; ;L

3;i5S.:^,.^A,;;-';; ?,j;
^ ••{,'•' **•
I.'-"-,

':'."i
3;? 1 'S •

V> i]SA

"S-.iSA

esm^.

WWVWWI—S-5

Stored-Enerey Operator Type ML-11

tOJ

GEI-S014S

2oa

SlG^O

' --'"ft ..

CAT. NO. FOR
215D472 G-1

NO. PER
MEOB.

OESCRIPnON

2150472 G-2

Reduction Gear Unit Complete (ML-llA, ML-llB)
4.16-150, 250; 7.2-250; 13.8-150, 250, 500
Reduction Gear Unit Con^dete (ML-llA, ML-llB)

2150472 G-3

Reduction Gear Unit Complete (ML-110)

215D472 G-S

Reduction Gear Unit Complete (ML-llD)

2650189 P-4
2650189 F-7
104A2451 P-2
2650189 P-S

Retainer
Nut

258C625 F-7
2650189 F-6
21SD472 G-50

215D472
215D472
215D472
2580626

G-51
G-S3
G-S2
P-10

2150472 P-37

7.2-500. 13.8-750

Spring Washer
Washer

Sprocket
Clutch Washer

Gear Assembly

Shaft, Bearing & "O" Ring (ML-11, ML-llA, ML-llB, ML-110)

Eccentric (ML-11, ML-llA, ML-llB. ML-110)
Pinion Gear & Bearing (ML-ll, ML-llA, ML-llB, ML-llC)

Gasket

Woodruff Key
Washer

Spacer

2580622 P-1
2580622 P-3

"O" Ring
"O" Ring
"O" Ring

Gear Housing
4.16-150, 250; 7.2-250; 13.8-150, 250, 500
Gear Housing
7.2-SOO & 13.8-750

104A2470
2560624 P-1
3150472 P-26
414A112 P-5

Spring

2580626 P-12

Gasket

6880553 P-8

Plug

2580626 P-20

Rachet Pin

N901P334
1S7A6028 P-1

137A6028 P-2

. 414A112 P-7
414A112 P-44

215D472 G-54
414A105 P-18

1/8 Dia X 1/2 Le

2580625 P-1
414A112 P-9
6404419 P-1
104A2407 P-2

2580626 P-19
2580626 P-14
2S8C626 P-13

2580626 P-21

Cover (ML-ll, ML-llA, ML-llB, ML-llC)
Plug

Bearing (Inner & Outer Race)

Retaining Ring
Spacer
Spacer

Bearing (ML-11, ML-IIA, ML-llB)

Bearing (ML-llC, ML-11D>
Roller 6 Bearu^
Washer
Cotter Pin

Latch Prop

Bearing

Ring Gear CmL-11)

(ML-llA, ML-llB, ML-110, ML-llD)

Motor Shims 1/64" Thk.
Motor Shims 1/32" Thk.
Motor Shims 1/16" Thk.
Spacer"

2580626 P-22

Screw

2650189 P-9

Gear Box Shims
Chain "
Sprocket

456A864
2580626
2150472
2150472

P-50
G-2
G-S6
0-55

2150472 G-57
2560624 P-1
Not Sbown

7.2-500; 13.8-750

2580625 P-10
121A5g98 P-S
12U5998 P-6

•

4.16-150, 250; 7.2-250; 13.8-150, 250, 500

414A105 P-10

121A5998 P-4

Pinion Gear & Bearing (ML-llD)

Shaft, Bearing 6 "O" Ring (ML-llD)
Eccentric (ML-llD)
Cover (ML-llD)

Fig. 24

(6026372)

ue'''

ro r^ rord
(0 o ao*
ro •g roc»

|r|1"'''

-i.'

Fig. 23

(8026371)

.'.KllidibnU^-

i 'lb;'' .1'".,

I II

" "M

Fig. 22

(8024797)

"•iii.'i 1!

•a
,r-

ro
A

Fig. 21 (80247S9)

ro r« N
ur t9 A

Stored^Enerey Operator Type ML*11

GEI-S0149

•

M. m

&270 266 283
i

278 257

m-':f1

S.
./ :

5'''

r277-i^

Fig. 25

REF.
NO.

CAT. NO. FOR
ML-11

HL-liB

NO. PER
M£CH.

OESCRIPTION

21SD466 G-1

Control Mechanism Complete (Less Coll)

215D466 G-1

(4.16-150, 250)
Control Mechanism Complete (Less Coll)

6880592 G-1

Control Frame

21SD465 P-32
215D465 P-15

Pin for Plun^r

619C421 P-8

Crank

215D464 G-3

Switch Trip Assembly

414A13S P-1

firing (ML-11 & ML-llA)
^rlng (ML-11 & ML-llA)

(7.2-250, 500; 13.8-150, 250, 500, 750)

104A2456
104A2456
215D465 P-49

21SD464
414A105
215D465
688CS53

P-13
P-10
P-38
C-1

Plunger

^rlng (ML-llB)

^rlng Retaining Washer
Spring Rod (ML-11 6 llA)
Washer

Pin (ML-11 & llA)
Crank Assembly

2I5D464 G-2
215D46S P-31

Prop

NBOOP-75
215D465 P-23
6176110 P-201

NP 166999A

2150466 G-3
215D465 P-36
2150465 P-1
6176109 P-77
215D465 G-2
414A112 P-2

688C592 G-2
2150465 P-27
2150465 G-7

Retaining Rli^
Spacer

Nameplate (Indicator)
Rod Assembly
Pin

Trigger Assembly
^acer

Prop Assembly
Bearing
Paddle Assembly
Support for NP
Swort

104A241D

^rlng

9921661 P-l

Switch (Open)

• Not Shown

(Continued on Next Page)

GSt-S0143

Stored-Ennrgy Op«ratar Type lOj-ll

REF.
MO.
280
281
282
283
284
286
288
287
288
288
280
281
282
282
282
282
282
283

CAT. Ma FOR
UL-U

104A24B5
8821881 P-2
258Ceil P-8
215D464 P-21
2150485 P-33
M80QP100P
1438840
2150485 P-30
2150484 P-30
414A108P-3
414iU08 P-5
414A112 P-3
6174582 0-1
6174582 G-2
6275070 G-1
6275070 0-2
6174582 G-14
121A7436 G-3

Ma PER
MBCH.

DBSCRlPTiaM

Heleaae Rcdler Storing

Switch (Closed)
Pole PlMO
Pin
Pin

Retaining Ring
Terminal Board

CoUSqpport

Pin (For BO. 11-B)
Washer
Washer

Bearing

Release Coil (12Bt d-c)
Release Coil 125(hr d-c)
Release Coll 24t d-c)

Release Coil i48vd-c)

Release Coil (2307 a-c)

Pry Bearing

ri9< 2<
REF.
NO.

4.16 STD.

301
302
303
304
305

6176109 P-285

306
306
307
308
• 309
310
310

310

2S8C638 G-1
258C628 P-3

7.2 6 13.8 STD.
258C638 G-2

Sprlns AttMbty Rtf. Ul

13.8 - 7S0
7.2 - SOO

NO. RSQ.
PER. MECR

DESCRIPTION

Spring Assembly Complete

6176109 P.28S
6176109 P-639

254D738 G-SO

2SBC628 F-3
6176109 P.28S
6176109 F.6S9
254D738 G-50

258C638 G-7
2S8C628 P-3

Spacer
Spacer

2S40738 G-SO

Crank & Bushing Assembly

254D738 G-Sl

254D738 G-51

2540738 G-Sl

Crank & Bushing Assembly

258C636 G-3
383A962
383A683

2S8C638 G-3
383A9B2
S83A983

2S8C63e G-3

Rod & Guide

S83A982

Spring (Inner)

456Ae09

6176109 P-639

2S8C642 P-12
258C642 P-11
25eC642 P-10

Not Required
Not Shown

258C642 P-12
258C642 P-11
256C642 P-10

(ML-llA, ML-llB)
(ML-llC)
383A983

2SeC642 P-12
258C642 P-11
258C642 P-10

^rlng (Outer)
$rlng (Inner)
Pillar Block Shims 1/64"
Pillar Block Shims 1/32"
Pillar Block Shims 1/16"

Fig. 27

REF.

Fig. 28

CAT. NO. FOR

NO.

118

HECH.

802B795 C-3
802B795 G-4

6319964 P-2

Secondary Disconnect Device Complete (*14 Wire)
Secondary Disconnect Device Complete (#12 Wire)
Plug

322

6505244 P-1

Socket

324
325

3663094 P-38

3
2

Spacer

366A234 P-1

326
327
328
329
330
331
332
333

6558756 P-1

366A6C0 P-1
6477418AA P-10

Ref. ii9

DESCRIPTION

848768 P-1

366A234P-2
366A234 P-3
6551725
366A611 G-1
6558748 P-1

1
1
16
16

320

325
325

Current Trip Hechanien

NO. PER

ML-11

118

319

Ref. 118

14
14
1
1
3
1
1

6076401 P-307

1
1

6477427AA P-8

L.KWasher for Plug
Contact Nut

Contact Nut (*14 Wire)

Contact Nut (*12 Wire)
^ring
Trip Pan
Bracket

Trip Latch

Trip Arm
Ball Bearing
Pin
Pin

OEZ.2800J

GENERAL ELECTRIC SALES OFFICES
UASY TO ASSIST YOU ... Wbta Yo« Hav* BwMod fnbttm ... NmU IHiitlwr lafefnwHan ... Ibqatra OnMng Imtivclltm
MAME
i OaralaRd 4..,
. .4966 Weedtend Ave*
Aogmla.
..IS] SlataSt.
Col»tabtfE 15o.,
^ t
.....aSOSE. Brood St.

SAu; omcE code key
* bdatMal EqvipaMal (bttlmRag Agwl oad

tElMrit UHll y EqsIpaiMl Sain

Soaaor.,

Di>lrilHriar)SalM

Mariaa and DofwiM Equlpmaal Sain
Conpoaaal Sain OpanHan

BlmlaalianS..
i MobSa 13....,

.21SI HlgMond Avo.
.704 Gavantmaftf SI.

* t 2

Batlimora 1....

Hagantam....

Phaaah 12
Tonoa

3550N.Ca.
1B3S Broadway

If.

IndioiiapoOt 8..
SiMtb Bond 1...

if-

Cadar RapUt.
....210 Socoad St.. S.E
Davaapatt.. 1039 Stala St, Battoadorf, lowe
DnMolan 12
2118 W. Oroad Ava.

Pert Wayno 6.

tOWi

KANSAS

* 1;..., ..W!«Mte 2

KB4IUCXT

200 E. PintSt.

Latdagten

B28 E.«/teIa St.

^^^^^teabrltla IS

2300Maadow Dr.

LOUKM

*
*:

. a. .303 NoOfoorfwoy

..l03Na Wyom{i>9 St.

Omaho 2..,

Alaaoadita.....
BetoaRougaB
Ma
Ml*, Onilti
vnan.1. . . .

.720 Murray St
3170 FteiMa BM.
422 Savaalh St

shrarnorl

20B Bodk BUg.
701 a SoraaHi St

• t t IfiwOifaoBS 12.

"•"t""

Wad Moaroa

837 Grcnrlar St

1420 Union Avn.
1717 W. End Ava.

......255 Main St., ^d

AbUoilO. a a. a •
Amaritlo
Boovfltoot

1583 CaUar Ava.

TEXAS

•409 S. Sovootoonth St.

442 Codar St.
SOSPelkSL

Carpui Chrlrtia.

NEVADA

UiVRGat..
Manchaitar.

. . . . . .215 N. Stoateo SL
408 W. Sovtatb St.
4219 Elcbotoad Ava.
5302 Avanu. "A"
704 S. Johaian St.

HouiIob 27. a • •
lubhodc
Midland
Sen Antonio 5. •

.1662 BaSt

NEW JERSEY

• t t * Naworfc2a..

20S N. Ctiaparral
.8101 Stammont Fnavray

DeUat7
D PolO
a.
Pert Worth2..

.17ri SpSHiSt.

NEW HAMPSHnifi

832 Gaargia Ava.
522 Coamwrca St.

.1501 Haaaoh Ava^ N.W.

Noihvlllo 3....
I OekRSdoo.....

NSOAASXA

. .108 W. Waibiagtea SL

Ktogiport
KooxviUo 16...
4....

t
T

OltliftQt
0«H*...,.aa

*t i

1310 lody SL

GrooflvUlo... •.

t S I Otattaooego 2.

SlOOliva St.

434 S. Mala Ava.

.520 Broad St.
UTAH

a120 Medtlra DrNogNaE.

Abegoorqaoaa a

•t

f SaltlakaOty 10...

....200 5. Mala St

VBMONT
NEW YORK

I i^anyS

•ft
%
*

Rutlaad

Boffalo2

VIROtNIA

} NnrpoitN.w«,P.O.Box1038.NawportNawS|Vo.

B2S Dakmrara A>a.

•Mala and Woodte^ Ava.
Ettniro
I Now Yeifc22... .......S70 loatngtea Avo.
NIogcra PeHi«..
44 Folb St

*I I SyrooiM
^hoitorBd

S9 EAyo.

Ullca2

3S32 Jamn St
509KaBlSt

NORTH CAROIMA

* t

Ckaitotta 1..

129 W. Tredo St

Gr..aibare.

4 t

RotNgb....

801 Svmmlt Avo.
IB W.MorHaSt

Bllmar^....

.418 Rotter Avo.

OHIO

BWiaaad 17
Roonoka IB

Coatoa 4.,

4 f t

Gncloaotl B.

Paico

• t t . SooltlaB

...824 W.UwbSt
...710SacoadAva.

...550 W.Mabo St.
S. 1B2 Pod St

I Soottla4.....

Spoiwna 4....

WEST VIROINIA

4
4

BknflaU
Charlaftea 28.

4 t
4

Folrewat
WkaaEag....

704 Stead St.

.30B MaeCaikl. Avo., S.E.
310 Jocabi BUg.
40 Fanitaaalh St.

«•

i Applaten............,510 W.CoUcga Avo.

BBS W. Maikot St

AkreaS.

5001 W. Bread St
920 S. JoHanaa St.

WASHBIOTON

VfBCONSIN

4 t
4 t

... .38W Caatar St

B CoMa A>a.

.19 Cbanongo St.

Blnghefflten. a. a.

NORTH DAKOTA

t
.

St lovit I

*
* t

Calvmbia 1..,»

TDMESSEB

MONTANA

...3750aMaiUlaaSt

BIO a MkMgan St

. .207 Ja-Fraa BUg.
.203 W. Capitol St

JopRn
220V^ Wo Povrth St.
Koaret Oty 5.. ... a.. 106 Wa FovrtaRftHi Sta

...200BN£ Parry An.

MDIAHA

•kcniw^

Gvlfpott.
Jodiwa 1

B40S.CaiMlSt

Rodcford

SOUTH CARCUNA

MISSISSIPPI

it!

3 Pana Caatar Plato

Pttlibtfrok22.. .Tba Olhtar BUg, Malton Sq.
755 Waihtegtea Bd.
Yoric
50-BB N. Hairlwa SL

S Pitti6er9(i28..

12 S.StethSt

NEW MEXICO

t I ChieaGo 00.

Naiby Bldo„ Raea 4

MISSOURI

Koitford 5

* I

t i PhMotphio 2 •

MtanaopoBi 3...

f
* T

752 Narlh IBib Si.
loot State SL
841 Oak SL

ErJo 2
Jottattown

14 W. Svpirlor St

201 UnNanily BM.

COmECTICUT

* t t

1170PaariSt.
107 E. Mala SI.
.2929 N.W.29lhAva.

PofHofMl 10

NtSYLVANIA
Aflootewd

927 S. Batdldt St

B14 Mkhlgon NaHoaal Towar
, .Socoad Nattonol Bonk BUg.

Oululh 2.......
Paigat PoRt

12407lliA»a.

COLORADO

a
MNOSOTA
tov

SaaB«maidlna.337aRIldaAva.,RlaIlo,Cal.

f SaaOlogaS

Euoono

lontlag 8..
Sagfam

321 Pallanaa BUg.

• t . LaiAagalnSA
^ t t
AngtinS

OMON

700 Aalolnalta St

B53 S. Saglaaw St.
Gread RopMs8, ... .2821 Modlna Avo., S.E.
Jadtrea.
2r0 W. FranUla St.

CAIIPORNIA

•

..272 lladleaoloAvoB

OUohana Qly 2
119 a Roblawa St
Talta 4
Columbia Bldg, 2B51 E. 2ltl St.

...31 StiannAva.

Darren 2
Paat2

•. a. .420 M^tioa Avo.

Yoaa9«towa7o

MIOilOAN

* t

Bldg*

119 Wb Pint St.

OKLAHOMA

•t

* t 2
*

.11 Wb

...137 Pork AvOagWotl

talRda 4

Ill PoikAao.
.1095 Jaffanaa BM.

ARIZONA

• t t
• t

Doytan 2 ,

Momfltld.a...

I DoytOQ

MASSACHUSETTS

ALABAMA

* t
•

.77 Ctatral St

MARYLAND

if
HAWAII:Afitgricctii FaNerti Ud., P.O. Box 3230, Honolata 1

...122BMaAatAva.a

Modlfoa 5

2B21 Victory Pkwy.

CANADA: CbasdlaaOtaeral DdclikCoinimy, ttdf Toronto

5317 Old MUdtetoa Rd.

MOwoukaa 3

940 W. St Pool Avo.

GENERAL ELECTRIC SERVICE SHOPS
WHBI YOUNSI SBIVICE . . . Thna O.E Mtvlca riwpt will repair, ncaadlttea,
aadrobolld yoar atecMc apparatea. Tba tadlHtea an availabte d^ oad algbli
nvaa day. a wnk, ler work la Mi. .hep. or on yoar protaitn. lotnt lacMty
ALABAMA

Biimtoghaoi. .P.O. Baa 3BB:%7—IBlh SL, S.W.

ARIZONA

matbodi and gmolaa 0*E raaowol port, an and to nMUotala paak-paifatniaBn
of yaw aqalpmtat. Par fall Infarewtlan oboaf Hion ncvlcn, coatacT yaur aaami
ttrvtea drep or tain oHba.
40anotet Aircraft Scivica Sbopt

KENTUCKY
•lovlrdno 9.

Tolodo 5.......a
g .3900 CrIttOAdon Orlvo

(PbooaliilOlmdala

4911 Wad Cotter St

Now OHoens.

2B15 N. Robortsen St

6900 Stenferd Avo.

MAXYLANO
Boifttnoro 30.

920 E. Pert Avo.

CAIIPORNIA

los Aagolot 1

*|Ui Angoloi] Ontorle
*
Onkkad

Portland 10
PEPMSYLVANIA

MASSACHUSETTS

(Bertoo) Modford 55

....OnlerielntomnHottol Airport
3400 Wood St

Seeromonte14

.99 North 17lh St,

$00 Noociice 3

..1098 Horrisea 8t'

COLORADO
Doavor5
cMCEcncur

Yegngttewo 7.

MICHWAN

Dotro{t2

5950 Third St

FLORIDA.

Jecboovillo 4
P.O. Box 2932.2020 W. Soovor St.

StleoUlO..NEW YORK

1115 Eotr Rood

5035 Poechtroo lAdutirlal Blvd.

1611 W. EQsobotfi Avo.
(Now York) North Borgon. N. J
. a. aa
6001 TOfmoQo AVOa

(Adeotol Cboabloo...
ItLINOIS

CMcoge 32

PtWoyoo
lodienepellt 22

Sehoftoctody (lotlmcxoRtotlon Sotvleol

4360 W. 47lh St

DJDtANA

1731 EdMllAvo.
1740 W. Vonnonl St

IOWA

1 RNof ROOd
NORTH CAROLINA

Choflfttto 8

*2328 Thrift Road

OHIO

(Dovooport) Boltnnderf
1039 Sioto St
KANSAS

*(Streth«f1AikomotOty. G.& Co., P.O. Bex 797

OncfoiMll 2
KlnctoftoH 32
a«v#tend 4

Midlood

115 Woee St

3202 Monor Way

5^4 Korvoy Wtlm Orivo

704 S. Jokfirton St

UTAH

1062 & 28»h St
P.O. Bex 1245

IMIoibI) Hiotooh
Tenpo 1.

Heuitoa 20

.3525 Gordnor Avo.

ABwny.
1097 Control Avo.
I^flolo 1 1 . a.31S Urheo St
*(Now York) Undon. N. J.

GEOROIA

841 Oak St

Dedot35

MISSOURI

Kormi City 20.

^httttown

CorpusChrfit).

Mtrnioopetlt 12 ........ 2025—-49th Avo.. N.

370 Alwalor St

; .665 E. HlgMond St

TEXAS

MDWESOTA

(Sooltdngtea) Pleofrvino

2727 N.W. 29tb Avo.

AUontewo

Phitodolpldo 24
1040 E. Erfo Avo.
(Pitfsburgbl Homottoed.
Box 308. RD 1g Bottoroulk HoDow Rd.
York
54 N. Horriseo St.

.3960 My^ VoHoy Poriimy

.3353 lortmor St

405 Dto'rbom Avo

272 E. ladlenolo Avo.

OREGON

LOUISIANA

444 W. Thfid St
260 W. Mttcbon Avoa
4966 Woodland Avo.

SotI Uko aty 4

301 S,7th Wort St

VIROINIA
Rkhmoad 24.
Rooaoko.a a a

..a.aa.»al403 fftgrom Avo.
P.O. Box 1327

115 i^ormoflo Avo.*$.&

WASHINOTON

3422 First Avo., S.
Soottio 4
220 Dowson St.
*Soattlo 8
Spokeno 3.... .. •».SooHi 155 Shonnen St
WEH VIROMIA
306 MocCorklo Avo.
Cheiiorton 28..
WISCONSIN

CoKtmbvt 23. .P.O. Box 6198* 2128 EofclnRd.

GENERAL ElEaRIC COMPANY, PHILADELPHIA, PA.

ApplolOn. a a a.

Midway Industrial Aroo
KO. Box 83 County Trunk P

Mitwotfkoo 3. a • ,..*....940 W.St Paul Avo.

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