(GE) Magne Blast Breakers 5k V Vol 2 Of 3

2018-02-16

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GEMGBLT2.XLS

G.E. - MAGNE-BLAST BREAKERS AND SWITCHGEAR (Volume 2 of 3)
TAB#! CATSECTI
noN
GEH-2003C

DESCRIPTION

Instruction Book and Renewal Parts

CONTENTS

AM-7.2-250-3
AM-7.2-250A-3
AM-7.2-500-3
AM-7.2-500A-3

with MS-13 Mechanism
GEF-443SA

Renewal Parts

AM-7.2-250/500-4

AM-7.2-250/500-6S
with MS-13 Mechanism
GEI-88763F & D

Instruction Book and Renewal Parts

AM-7.2-500-5/6 with ML-13 Mech

Instruction Book and Renewal Parts

AM-7.2-500-6

AM-13.8-150-3&A-3
AM-13.8-250-3 & A-3

AM-13.8-500-3 &A-3

AM-13.8-500B-3 & AB-3
With MS-13 Mechanism

Recommended Parts for Maintenance

AM-13.8-250-4, 6S. 6U & 4ML

AM-13.8-500-4, 6S, 6U, 4ML & 4V
With MS-13 & ML-11 Mechanisms

GEK-311118

Instruction Book and

AM-13.8-500-7 1200 & 2000A

Recommended Parts for Maintenance

Instruction Book and Renewal Parts

AM-13.8-500-5A, SAB, 5C, 5CB, 5H, 5HB

GEI-88764E

Instruction Book and

AM-13.8-500-5C, 5CB, 5H, 5HB, 5HV, 5HVB

Recommended Parts for Maintenance

AM-13.8-500-6C, 6CB, 6H. 6HB

AM-13.8-500-5C & 5H
AM-13.8-500-6C&6H

Instruction Book and Renewal Parts

GEK-7345B

Instruction Book and Renewal Parts

AM-13.8-750-5 (1200&2000A) with ML-13 Mech
AM-13.8-750-5 (1200&2000A) with ML-13 Mech

GEI-8876SA

Instruction Book

AM-13.8-750-2C. 2CB, 2H. 2HB

AM-13.8-750-3C, 3CB, 3H, 3HB

GEK-7347B

Instruction Book and Renewal Parts

Page 2

AM-13.8-1000-4H

MAGNE-BLAST CIRCUIT BREAKER
TYPE

INTRODUCTION
The magne-blast circuit breaker is the

and cooling iL

This is accomplished by

called upon to operskte at voltages or cur

removable interrupting element for use in

means of a

strong magnetic field that

vertical-lift metal-clad switchgear, toprovide reliable controlandprotection of power

rents greater than those given onthename-

lengthens the arc and forces it into intimate
contact with cool dielectric material.

systems.

sturdy, reliable operating mechanism as

plate. Since this book is written to cover
several ratings of breakers that are of (he

Among the many advantages of

metal-clad switchgear are added protection
to equipment and personnel, compactness,
simplified installation and reduced main
tenance.
In keeping with these features
the magne-blast breakers are designed for

interchangeabillty and maneuverability, to
gether with reliability and low maintenance
requirements.

The magne-blast circuit breaker oper
ates on the principle that an arc can be

interrupted in air by sufficiently elongating

sures low maintenance and long life, and
the use of Self-X insulation r^uces fire
hazards to a minimum.

be of a general character and all illustra

tions will be

^Ical, unless otherwise

specified.

The AM-7.2 magne-blast breaker is

available in a number of current ratings.
Refer to the breaker nameplate for the
complete rating information of any par
ticular breaker.

same general design, all instructions will

The short circuit condi

tions to be imposed on the breaker must
not exceed its rating, nor should It be

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

OF THE BREAKER.

The following In

structions will provide information for
placing the magne-blast breaker in service

and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
RECEIVING AND HANDLING

crate or any part of the breaker.

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

proper handling and packing of electrical
equipment. Immediately upon recelptofthe

ways Included in the same crate.

sure that no parts have been overlooked.
STORAGE

made for any ctemage sxistained in transit.

If Injury or rough handling is evident, a
damage claim should be filed Immediately

It is recommended that the breaker

^earest GeneralElectricSalesOfficeshould

be put Into service immediately In its
permanent location. If this Is not possible,

the transportation company and the

e 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 handlhig, or
from ezqMSure to moisture or dirt.

nail puller should be used to open the
crates, and care should be exercised to

prevent tools from striking either the

is available and the heatersare Inoperatlon
to prevent condensation.

Check

all parts a^lnst the packing list to be

circuit breaker, an examination should be

Loose

parts associated with the breaker are al

the following precautions must be taken to
insure the prefer storage of the breaker:

1. The breaker should be carefully
protected 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 should be

stored In the equipment only when power

2. The breaker should be stored in a

clean location, free from corrosive gases
or fumes; particular care should be t^en
to protect the equipment from moisture
and cement dust, as this combination has a
very corrosive effect on tnany parts.

3. Machined parts of the operating
mechanism, etc., should be coated with a

heavy oil or grease to prevent rusting.
If the breaker is stored for any length
of lime, 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.

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

element comprises threesimilarpoleunits,
each pole unit consisting of mainandarclng
contacts, an interrupter, and an enclosing

1. Secondary Coupler
2. Auxiliary S«itch
3. Position Indicator

box barrier that segregates the Internqjting
units from each other to provide insulation

4. Opening Spring Unit

between phases as well as from each

6. M^uai Trip

phase to ^ound. The primary connecUons
to the associated metal-clad equipment are
made through the primarydisconnectstuds.
The MS-IS operatingmechanlsmshown

5. Operation Coixiter
7. Control Device

8. Control Device

Plunger Guide
9. Closing Solenoid

in Fig. 1 Is of the solenoid type designed
to give h^ speed closing and opening.
The closing operation is controlled by the

control device (7). The control device also

fig. I

KS-13 Operating Hechanisn

There fnrfrvcfionr do not purporf to cover oM de»oi7i or variations in equtpmofi/ nor to provide (or every potable

confingeney fo be mel in connexion vrilh inslollation, operation or mainletianee. Should further information be desired

or ahwid parlieular problems etitewhich orenot covered suffkiently for fhe purchorer'r purposes, the matter should
be referred to the General Efecfn'c Conipan}'.

GEH-2003

Magne-blast Ctrcbll Breaker Type AM-7.2-3

gives high speed closing and opening. The

closing operation Is controlled bythecontrol
device (7). The control devlce^opermtte

trip free operation (tripping the Isreaker at

any time during the closing operation), and
prevents solenoid pumping (recloslng) after

a trip-free operation.

operates.

For a-c closing

The breaker can be cpened

electrically, by remote control, or manual
ly, by means of the manual trip device (6).
AU secondary connections from the breaker

to the metal-clad unit are made throu^the
coupler (1).

switch are provided between the breaker

breakers are identified by the "A" suffix

and metal-clad unit to prevent the raiaing

or lowering of the breaker in the unit while

(AM-7,2-250A-3). This mechanism is con-

In the closed position and to prevent a

trolled by a relay scheme mounted In the

closing operation when
breaker Is not
In either the fully ralaed or lowered posi

metal-clad unit and a cut-off swltchloca^

tion.

A plunger type Interlock can also be

provided to prevent the closing of two
adjacent breakers at the same time or to
^erate an additional auxiliary switch

positive

Interlock

and Interlock

The operating mechanlsmused on those
breakers designed for MI-6 metal-clad
equipment differs somewhat from those
for

operation Is principally' the same. These

on the breaker Instead of the control de

vice.

Two seven-terminal

secondary

couplers also replace the one slxteen-ter-

mlnal coupler.

The positive Interlock

between the breaker and metal-clad unit Is

the breaker can be accompltsned. A forktype lever can be furnished lo operate an
auxiliary switch mounted in the metal-clad
unit. For detailed explanation of theoperatlott of the breaker and mecltanlsm refer

to the secuon OPERATION.

INSTALLATION
All adjustments should be

The following InstrucUons explain the

checked

not only during the initial Installation of

necessary steps to be taken bmore the
This Includes a complete check of all of

the breaker but also during periodic In
fections and whenever It becomes nec

the breaker adjustments, in addition to a

essary

thorough inspection. For final installation

have become worn or defective while in

breaker is placed In the metal-clad unit.

instructions refer to the metal-cladswltch-

gear Instruction book.

service.

repair or replace parts that

The following aitJustments are

listed In the order in which they are to

Reference should

also be made to the connection diagram

'-''f •
t

^ t Is furnished with each unit.

be checked.

First, however, remove the

breaker from the metai-clao unit and re
move the box barrier and the mechanism

DO NOT WORK ON EITHER THE
BREAKER OR THE MECHANISM WHILE
IN THE CLOSED POSITION UNLESS THE

cover.

PROP

When the breaker is closed, as shown
In Fig. 3, the stationary primary contacts

AND

PRIMARY CONTACT WIPE

TRIP LATCH HAVE BEEN

SECURELY WIRSDORBLOCKBDTOPRE
VENT ACCIDENTAL TRIPPING.

(1) should rise 5/18" + 0-1/6". To obtain

this adjustment, open the breaker and,

ADJUSTMENTS

referring to Fig. 4, loosen the check nui

(4) and turn the adjusting nut (3). Screw

Althou^ the breaker has been com

pletely adjusted and tested at the factory.
It is possible that unusually rou^ handling
during transportation may have caused

some loosening or disturt^ce of parts of
the apparatus. It is therefore advisable to
review all adjustments before placing the

breaker in service, making readjustments
wherever necessary.

ing up on the adjusting nut will decrease

the primary contact wipe, down will in
1. Closing Armature Cover
2. Handle

i . Meintenance (grating Device
4. Belease Valve

crease It.

Tighten the check nut, close

the breaker and recheck the wipe.

With

the primary contact wipe correctly ad
justed. the clearance between the contact
arm (7) and the buffer block should be

1/16" or greater (as shown In Fig. 3)
Fig. 2

Method of Mounting Maintenance

when the breaker Is (uUy closed.

Operating Device

A maintenance operating device Is
provided for operation of the breaker dur

ARCING C

ing these adjustment checks, lilount the
device as shown in Fig. 2, and turn the
release valve (4) llrmly to the right. To

armature will return to Its normal posi

with a pumping motion. By turning tiie
release valve (4) to the lef^ the closing

several

tion.
Electrical operation must not be
attempted until the breaker has been aer

close the breaker, merate the handle (2) ated manually throu^ Its complete stroke
times and final

Installation In

spection has been completed.

-NTACT WIPE

Refer to Fig. 3.

Close the breaker

until the arcing contacts just touch. This
can be determined with the use of a cir

cuit continuity tester such as a U^t in
dicator or bell set In this position, the
t>etween thestationary primary contacts

1. Stationary Prisury Contact!
2. ibvable Prlnary Contaeta
3. Buffer Block

4. Stationary Arcing Contaeta
5. Movable Arcing Contaeta
6. Coll Protector
7. Arc Sunner

Pplesry Contact Bipe

Arcing Contact Kipel
Fig. 3 Cmtact Adjuataents

replaced with a trip Interlock that trips the
mechanism before raising or lowering of

mounted In the metal-clad unit.

designed
A

the

Magne-blast Circuit Breaker Type AM-7.2-3

1- Operating Bod
2. Operating Rod

5. Stationary Primary
Contacts

6. Movable Primary

3. Adjuating Nut

-26

Contacts
7. Contact Am

4. Check Nut

GEH-2003

Fig. <1 Adjustable Coupling for Making
Primary Contact KIpe Adjustnent

(1) and the movable primary contact (2)

should be 5/16" or greater.

This setting

has been made In the factory and no ad
justment is provided. A wipe of less than

5/16" is usually an indication that the arc
ing contacts need to be replaced.

When

making this check, also see thatthe movable

arcing contact (5) passes through the slot

in the upper arc ninner(e)wlthouttouching.
I^tlMARY CONTACT GAP

Refer to Ftg. 4.

With the breaker

closed,
press the manual trip button
allowing the breaker to trip open nor

mally.

Do not force the contact open

wider by hand.

The

gap between the

^^tetlonary primary contacts (5) and the

^«vable primary contact (6) should be
/4" + 5/16" -1/8". To change thU
p, loosen the check nut (25), Fig. 5, and

turn the adjusting nut (26) on
on stud (9).
Screwing the adjusting nut down will de
crease the primary contact gap.

Ti^iten

the check nut and reneasure the contact

gap

(close and trip the breaker before

checking the measurement).
TRIP LATCH WIPE

Refer to Fig. 5. The wipe of the trip

latch (4) on the trip roller (6) should be
—• - w

ured by putting a film of grease on the

latch (4), closing the breaker part way,

and tripping. ThemechanismhasUieproper
trip latch wipe when the latch rests against
the stop pin (5). No adjustment is provided
and a visual inspection is usually all that is

required.

If &is setting is not correct,

. look for insufficient travel of the trip
—
W

1], Opening Spring Housing
Trip Shaft
12. Opening Spring, Inner
Trip Latch
13. Opening Spring, Outer
Trip Latch Stop
14. Closing Roller
Trip Holier
IS. Prop
Position Indicator 16. Closing Coil
Clevis
17. Closing Plunger
Adjustable Stud
16. Piston Ring

19. Set Screw
20. Slims

21. Closing Armature
22. Stop Nuts
23. Ameture Guide Bolts

24. Stop Nuts
25. Check Nut

26. Adjusting Nut

WHEN WORKING ON THE MECHAN

ISM IN THE CLOSED POSITION, KEEP
FINGERS CLEAR OF THE LINKAGE, AS
ACCIDENTAL TRIPPING CAN CAUSE SE
VERE INJURY.

With the breaker

closed as far as possible with the main
tenance device, the clearance between the

closing pin (10) and the prop (15) should

be 1/32'' to 3/32".

Measure the prop

Plunger Guide

at which the contacts make can be deter

The point

mined with a circuit continuity tester such

as a light indicator or bell set To obtain

adjustment on the latch checking switch (7),

Control Device

With the breaker in

To change this adjust

ment, add or remove washers (3).

3. Top Aueliiary Switch
4. Plunger
5. Operating Ana

latch checking switch arm (5).

Refer to Fig. 9.

the open position, the vertical distance "A"
from the top of me Interlock bolt (2) to the
bottom of the elevating bar (13) should be

. AUXILIARY DEVICES

2> Mounting Screw

After checking all the mechanical ad

justments as outlined above, operate th^
devices manually to make certain (hat they ^
A
trip and reset properly.

adjustment.

bend the latch checking switch arm (6). ITie

AUXILIARY SWITCH LINKAGE

(FURNISHED SPECIAL ON 7.2-150A, 250A,
500A)

Refer to Fig. 10. With the breaker

the open position, the distance from tK
centerline of the front bushing (1) to tl.

Magne-blast Circuit Breaker Type AM-7.2-3

1^,

GEH-2003

FINAL INSPECTION AND TEST

For ease In reviewing the adjustments,
the following are recapitulated:

a. Primary contact wipe: S/16"
- 1/16".

greater (gap at primary contacts).

c. Primary contact gap:

8-1/4" + 5/16" -T/S".

d. Trip latch wipe: 3/16" to 1/4" with
trip latch resting against stop pin.
e. Prop clearance:

1/16" + 1/32".

f. Clqslnjg plunger clearance:

1/16"

g. Interlock switch w^ie: 1/32" to 1/16"
overtraveL

h. Control device switch overtravel:

1/32" mln.
L Cut-off switch overtravel:

1/32"

]. Latch checking switch wipe:
to 1/16" overtraveL

1/32"

k. Impoct trip roller wipe:

1/6" *

- 1/16" (150A, 250A, SODA).

1/32*'.

cleara^:

3/64"

m. Undervoltage trip hammer clearance:
3/64" + 1/64".
n. Plunger Interlock: 10-7/32" + 1/16".

o. Auxiliary switch linkage:

(ISQA,

250A, S(^) 13-7/32"breaker closed,

1. Front Disconnect Stud
3. Interlock Bolt
3. Washers
4. Osnnecting Bod
S. Boiot Plate
6. Reset Boiler
7. Main Operating Shaft
8. Beset Am

Fig. 9

9. Trip Plate
10.
11.
13.
13. Elevatint Bar
14. Inpact Trip Plate
IS. Trip Latch
16. Trip Roller

17. Trip Armature
18. Trip Lever

19.
30.
21.
32.
33.

Undervoltage Trip Baaner
Adjuating Rod
Manual Trip Button
Trip Setting Plate
Undervoltage Device

12-1/4" bredker open.

p. Auxiliary switch, "a" contacts close

when breaker primary contact gap Is
1" or greater.

Adjustnents On Current
Tlie Breaker In The Closed Positien

center of the switch operatl

be 12-1/4" as shown.

(13-7/32" with the
breaker In the closed position). To change
this setting, loosen the locking nut (6),
remove the pin (4) and turn the clevis (5).
Reassemble and check adjustments.
Auxiliary Switch

1. Front Bushing

The auxiliary switch is mounted on the

3. Fork Lever

right side of the operating mechanism (2),

3. Operating Pin

Fig. 1.

4. Pin
5. Cievis
4. Qwek Nut

The shaft of the position indicator

operates the auxiliary switch shaft which
opens and closes the "a" and "b" contacts.

(The "a" contacts are openwhen the breaker

Is open and the "b" contacts are open when
the lureaker is closed). The "a" contacts

should close when the breaker primary
contacts are 1" apart

The "b" contacts

need only to be checked to see that they

are open when the breaker is closed

Fig. 10 Auxiliary Switch Linkage Shown With The Breaker In The Open Position

GEH-2003

Hagne-blast Circuit Breaker Type AM-7.2-3

2. Check all nuts, washers, bolts, cotter
pins, and terminal connections lor tight
ness.

3. Inq;>ect all wiring to make sure that no
damage has resulted during Installation,
and test lor possible grounds or short

RECTIPIER REPEHEMCE CHART
Cloalng Coll
Dug. no.

6. Operate the breaker slowly with the
maintenance closing device and note that
there Is no'excesslve binding or IrlcUon
and that the breaker can be moved to the

Resistor

62.0

4. See that all bearing surlaces ol the

fully opened and fully closed positions.

Silicon

Tans

circuits.

mechanism have been lubricated, Reler
to the section on LUBRICATION.

Rectifier Resistor Setting
uenuaniuB

6. See that any place where the surface ol

•3SI

the paint has been damaged during In
stallation Is repainted Immediately.
HI-POTKNTIAL TEST

If the breaker had been stored lor a

long period ol time, it is recommended
that the insulation be checked before the

operatbg ranges lor beclosbgandtrlppbg
volbges are given on be breaker namepbte. Ordinarily, standard ranges apply

tmeaker Is placed In service. A standard
60 cycle Ugh potential test at 27,000 volts
RMS will normally indicate whether the

which are as follows:

breaker is satis&ictory lor service. With
the breaker contacts in the fully opened

NOMINAL
VOLTAGE

terminal of the breaker Individually lor

position, ^ply the high potential to each
one minute with all other terminals and the

breaker frame grounded.

Alter high po

tential tests are made on organic insulaUng

materials, these materials should be In
spected for visible leakage current paths,
and necessary action must be taken to
rqtlace Insulntlnn that may have been

affected by moisture absorption. The high
potential test is also recommended lor
breakers which have been removed from

service and stored over an extended period
of time under unbvorable atmospheric
conditions.

On breakers that are equipped with

anxOlary devices such as current trip,
. undervoltage trip or capacitor trip, the
device should be checked for proper elec
trical operation. The current trip device

should &lp the breaker at 3 amperes. The
undervoltajge trip device should trh> the
breaker when the control voltage drq;>8
below 30 to 60% of rated voltage, and It

NOTE: When repetitive operation b re
closed circuit voltage at be closbg coll
'should not exceed llSv d-c and 230v d-c

at be nominal voltages ol 125v d-c and
250v d-c, reflectively.

coll termlnab, proceed as follows:
1. Mechanbm wlb a control device. Fig. 7.
Close be breaker by manually fieratbg
be control device. Hold be ceratlng voltages should be checked

at be closing coU
trip coll termlnab.
For electrlcu operation ol be breaker,

be control power may be elber an alter

nating or direct current source.
8

The

read be d-c voltage at be closbg coll

de-energbe the circuit.

If the closed cbcult voltage at be
termbab of be closbg coll does not fall
In be specified range, proceed as follows:
1. A-c conbol power source using copper

A-c volte as measured across be recti
fier and a-c serbs resbtor.

The preceding tabubtlon b bcluded as
a guide for adjusting be resbtors for

t e particular combination of ambient

temperature and a-c sumly voltage.
Summer settings are used where ambient
temperatures are normally above freez-

bg (SS^'F).
wbbr

2. Mechanism wlb cut-off switch. Fig. 8.

Resbtor Settbg for

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

quired from a direct current source, be

termbab. Release be closing reby to

the undervoltage device colL The device
should pick tm at thb value. Do not b-

110 to 120 volts d-c.

be volta^ should be set at 105 to 115

TRIPPING
RANGE

on the &ont of the undervoltage tr^ device
as an aid b obtaining the desired settbg.

equal to 80% ol normal control volbge to

circuit volta^ at be breaker closbg

CLOSING
RANGE

or less. An adjustment plate is provided

NOTE: When checkbg be pick-iq> value ol
the undervoltage devbe, apply a voltage

The resbtor settbg

Where repetitive operation b required,

Close be breaker by manually operatbg
be control reby located b be metalclad unit. Hold be reby closed and

should pick iq> at 80% of the control voltage

be d-c vblbge.

should be adjusted so that be closed
coll termlnab b

To check be d-c volbge at be closbg

AUXILIARY DEVICES

vided b each rectifier circuit to control

It b necessary to use

settings where

the

ambbnt

temperature may drcp to 20t'F or bss

at any time.

For a more detailed ex

planation of cfiper-oxlde rectifiers for
cbcult breaker application, refer to
instruction botdc GEI-11308.

2. When a «*ri»niiHiim (color-black, flanged base) - or a sUleon (color-blue
hex base) - recUfbr bridge assembly b

used, it b mounted b the metal-clad I
unit. Ibese rectifiers are ofbebutton-

. type and are hermetbaUy sealed units.
TbOT have been testedand the associated

Decrease be serbs

resimr properly set at be factory.

resbtance to Increase be d-c voltage,

Vidbe cfiper-oxlde rectifiers be Otttout
of be germanium or silicon unit b
auected very little by ambbnttomperature changes and it mould not be neces
sary to disturb be factory setting.

oxide rectifiers.

or bcrease be series resbtance to

decrease the d-c voltage. Recheck
voltage at be closing colL
2. D-c control power source. Check volt
age at be source of power and Ibe
drop between be power source and
breaker.

DO NOT MAINTAIN VOLTAGE ON THE
CLOSING COIL ANT LONGER THAN THE

TDIE
FOR A-C OPERATION

1. When copper-oxide rectifiers are used
bey are mounted b be metal-cladunlt.

A tapped 1-1/2 ohms resbtor b pro-

REQUIRED

THE

BREAKER. (20 Cyctes maxlmnmatnorn
voltage.) Bobbecolbandthegermaniu
and sllbon rectifiers are designed fc
btermittent operation and may be damageo
by prolonged current flow.

Magne-bUst Circuit Breaker Type AM-7.2-3

When two or more breakers, operating

the same control power source, are

jlred to close simultaneously, the closed
..cult voltage at the closing coil of each

broker must fail

within the specified

clad unit

It is also possible to trip the

breaker manually by pressing the manual
trip button (6), Fig. 1.

NOTE: This breaker mechanism com

safely placed In service.

Before the

complished by merely energizing thecloslng

breaker Is finally raised into position in
the metal-clad unit, rub a small amount of

or trip coil circuit.

G.E. Contact Lubricant D50H47

Electrical closing or opening is ac
Control switches are

provided lor this purpose on the metal-

silvered portion of the breaker studs to

form a thin coating forcontactlngpurposes.

bination is designed on^ for electrical

When all the foregoing inspection de

tails have been checked, the breaker maybe

limits.

GEH-2003

on the

closing when in use, nFver 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 mechananism. The closing sequence is initiated
from

control

switch

1. Shunting and Antl-puip Saitch

mounted on the

2. Seal-in Switch

door of the metal-clad unit or at a remote

3. Operating Coil

operating station. Operation of the closing

4. Crank

control switch energizes the pickup coil

5. Stationary Contact Aasenbly

6. Movable Omtact Asaeobiy

device closes, seal-in contacts shunt the
closing control switch to allow the open
ing of the closing control switch contacts
without
affecting the overall closing
operation.

Tbis

7. Am
8. Arc Quite

9. Trip Lever
10. Plunger Qiide

of arrangement as

sures complete closing of the breaker with

only momentary con&ct of the closing
control switch.

Fig. II

Control Device

Operation of the control device ener
gizes the breaker closing coll by closing

&ie main control device contact ^ and 6),
Fig. 11.

Once the control device contacts

e picked tqt, they are electrically held
the closed position until the breaker
islng operatloa is completed. Energizing

r—

•e breaker closing coil raises the arma

ture (6), Fig. 12, which In turn lifts the
closing roller (4) throu^ plunger (14).

1. Main Crank

This motion is transmitted through the
mechanism linlo^ and rotates the main

crank (1), closing the breaker contacts.

2. Trip Latch
3. Trip koller
4. Closing Roller

As the armature reaches the end of its

5. Piston Sing

travel, the prop (12) rotates twneath the

6. Closing Araaature

pin (11) latching the breaker in the closed

7. Anuture Ouide Bolt*
8. Spring Retainer

position. During the closing operation, the

opening springs (9 and 10) are compressed

9.
10.
11.
12.
13.

in readiness for an opening operation. Air
trapped above the armature acts as a dash
pot to absorb the energy of the mechanism
as it approaches the end of ite stroke.

Opening
Opening
Closing
Prop
Closing

Spring, Inner
Spring, Outer
Pin
Coll

14. Closing Plunger Rod
When the solenoid armature is near the

end of its stroke the control device plunger

(5), Fig. 22, mechanically trips the main
control device contacts, de-energizing the

•

closing coil and allowing the armature to
return
by gravity to its original position.
The con&ol device plunger also mechani

cally trips theseal-inswitch, de-ener^ztng

the control device coll if the closing control

switch is not closed. If the closing control

switch is held in the closedposition Oirougb
and after the breaker closing operation,

Fig. 12

the control device linkage will remain
picked up and be unable to reset to prepve

for another breaker closlngoperation. ^is

arrangement insures that "pumping" of the

breaker will not occur during a ^ip-free

Crosa Section of MS-13 Operating Hechanlen In the Open Position

(Fig. 6) is used to replace the mechanical
trip arrangement of the control device.
The cut-off switch energizes an auxiliary
relay to de-energize the main relay.

for those

^.M^breakere designed for Ml-6 metal-clad
Equipment is similar to that described

bove except that a relay mounted else-

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 iqiper
arc runner to the tangent position.

The closing speed of the arcing contact
should be 7 to 10 feet per second for the

iSO, 250 MVA breakers and 9 to ISfeet per

.vhere in the metal-clad unit replaces the

second

control device.

rated closed circuit voltage at the closing

Also, a cut-off switch

coU terminals.

for the 500 MVA breakers with

OPENING OPERATION

An electrical opening operati<» Is in
itiated by energizing the trip coU. This is

GEH-2003

Magne-blast Circuit Breaker Type AM-7.2-3

accomplished either by actuating the opening
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 plunger rotates the trip latch (2),
FU ; 12, causing the operating mechanism
linkage to collapse. The energy stored in
the opening springs (9 and 10) is thus
released, cg>ening the breaker. During this
operation, the trip coil circuit Is de-ener-

^ed, and upon completion of the opening

introducing a magnetic field between the

is so long and the gases produced lav

pole pieces which tends to draw the arc
away from the arcing contacts. The 150

establish Itself, and Internption occur

and 250 MVA interrupter contains three
upper magnetic blowout colls and one lower
blowout coil each individually connected In

series with its respective section of arc
runner. The 500 MVA interrupter contains

three «q>per blowout colls and three lower
blowout colls each Individually connected in
series with Its respective section of arc
runner. As the arc is forced outwardalong

operation, the (gierating mechanism is re
turned to its normal position, ready for
closing.

the diver^^ arc runners, the magnetic
field is progressively increased wflh the

As the breaker opens, the main contacts

At the same time, the arc Is being
forced Into the arc chute (8) which is

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

addition of each coll in the circuit.

composed of a series of gradually Inler-

the arc so cooled that the arc cannot r^'^^X

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

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

The (penlng speed of the arcing eontact should be 10 to 15 feet per second at
rated control voltage. 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 on the unfailing

performance of the power circuit breaker.
To maintain such service, it is recommend

or if the arc chutes are removed for any

reason. When Inspecting an arc chute, it

should be disassembled and the following
points noted:

ed that a definite inspection and maintenance
schedule be set im and followed, as serious

1. Scale formed over the surface of the

shutdowns can often be avoided by locating

arc chute must not be removed, but

potential sources of trouble in an early
stage. A periodic lubrication of parts sub

loose articles collected in the chute
should be blown out.

ject to wear is also vitally important for the
successful operation of the breaker.

2. Cracks which have formed in the fins of

BEFORE ANY MAINTENANCE WORK
IS PERFORMED. MAKE CERTAIN THAT
ALL CONTROL CIRCUITS ARE DE-ENER-

fine cracks do not interfere with the

GIZED AND THAT THE BREAKER IS RE
MOVED FROM THE METAL-CLAD UNIT.

DO NOT WORK ON THE BREAKER OR
MECHANISM WHILE
IN THE CLOSED
POSITION UNLESS THE PROP AND TRIP
LATCH HAVE BEEN SECURELY WIRED
OR BLOCKED TO PREVENT ACCIDENTAL

ed to the severe hea. of an arc. Ibese

operation of the device in any way and

should be disregarded.
3. If the arc chute has suffered any mech
anical injury
due to
dropping or

accidental striking, resulting In the
actual breaking off of fins, replacemeht
of the chute will be necessary. Small
broken corners in the exhaust end of
the chute will not interfere with its

TRIPPING.

performance and can be disregarded.

PERIODIC INSPECTION

The frequency of periodic inspection
should be deternwed by each operating

company on the basis of the number of oper
ations (including switching), the magnitude

y hardening and dark
ening in color. Elimination of the hardened

lubricant is essential for the proper cgierj ^

ation of circuit breakers. Also freque:
retaining rings. All cam, roller and latch
surfaces should be inspected for any evi
dence of damage or excessive wear. Lub
ricate the mechanism as outlined below,
then, using the maintenance operating de
vice, open and close the breaker several
times to make certain that Hie mechanism

operates freely throughout its entire stroke.
Check the mechanism adjustments as spec
ified under INSTALLATION, ADJUST
MENTS,

Check all terminal connections.

BUSHINGS AND INSULATION

The surface of the Self-X bushings

should be kept clean and unmarred to pre
vent moisture absorption. If the insulation

surface should become damaged, it should
be sanded and cleaned, and should be
refinlshed with either clear varnish (GE-

1170) or clear Glyptal* resin (GE-1202).

Allow to dry smooth and hard.
All other insulation parts on the break
er 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 to
insure dryness.

LUBRICATION

In order to maintain reliable operation,
it is important Uiat all circuit breakers be

properly lutoicated at all times. During
assembly at the factory, all bearing sur

faces, machined surfaces, and all othe^
parts of ihe breaker and mechanism sub'

Ject to wear have been properly lubricated

* Reg. Trade-Mark of General Electric Co;

Magne-blast Circuit Breaker Type AM-7.2-3

GEH-2003

1. Box Barrier Catch
3. Box Barrier
3. Arc Chute

4. Arc Rumeri Upper
5. Biow out Coil, Upper
6. Blow (Xit Core, Upper
7. Movable Arcing Ctatact
8. Arc Runner, Lnrer

9. Blow Out Coil, Lower
10. Blow Out Core, Lower

11. Pole Pieces

31. Stationary Prioary Contact
33. Movable Prlaury Contact

13. Front Bushing
13. Rear Bushing

33. Movable Contact Arsi Assesd>ly

14. Upper Rorlsontal Barrier

34. Ckip Bearing

15. Main Operating Craqk
16. Arc Chute Support
17. Spring Retainer

35. Booster Tube

36. Front Vertical Barrier

18. Lower Rorlsontal Barrier

37. Check Nut
38. Cannection Bar

19..Operating Rod
30. Stationary Arcing Contact.

30. Side Barrier

Fig. 13

39. Booster Cylinder and Piston

Cross Section of Breaker Pole Unit

GEH-2003

BAagne-blast Circuit Breaker Type AM-7.2-3
RECOMMENDED MAINTENANCE FOR

•

Alternathre Lubrication

LubrlcaUon at
Maintenance Period

Part

(Reqatres Disassembly)
Wipe clean and apply OSOHIS.

OrottDd KiTfMM (iich as

Wipe clean and apply

eamfl, roUsrs, latehss, etc.

DSOHIS.

Steere Bcarbigs

Very light appUeatlos of light

(Mtchanlsm and Breaker
Untage)

oU 8AE-20 or -SO.

Remove pins and links and clean

as per cleaning Instmetloas below.
Apply DMBlSliberaUy.

REPETITIVE SWITCHING DUTY

Magne-blast breakers applied to re
petitive eration such as switching arc

furnaces, capacitors and motors sho^ be

machine oU SAE-20 or -20.

Clean as per cleaning Instructions
below and repack with DSOBtS.

serviced and maintained according to the
following schedule:

Wtgeleu and apply

Wipe clean and apply DS0H4T.**

A. Every 2000 Operations, or Every Six

Do not lubricate.

1. Cop Bearing

No lubrleatlon re 14

No lubrleattoa required.

also the inside of the box barriers.

using the finest grade of lubricants avail

amount - of G.E. Lubricant DS0H15 to the
entire surface of the bearing and pin just
before reassembling.

ening in cRIDE. If

badly oxidized, it may be necessary to use

alcohol (^e used for thinning shellac) to

remove it Ordinarily, by agitating ihe
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 onto the bearings
are indnctve to corrosion. If the-bearings
are touched, the contamination can be

slower.

General Electric Lubricants D50H1S

and DSOEdT areavailable in 1/4#collapsible
tubes. It is so packaged to insure clean
liness and to prevent oxidatian.
UBTHOD OF CLEANING BEAHING

Vherever clearing is re^piired, as in
dicated inthe lubrication chart, the fulowing
procedures are recommotded:
Sleeve Bearings

The pins should be'removed-and all

old oxidized grease removed by immersion
in clean petroleum solventor similar clean
er. DONOTUSBCARBONTETRACHIXIR-

IDE. Wipe the bearingclean.Applya small

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 conmcts indicate the prob
able need for arcing contact re
placement). If the contact surfaces
are only roughened or galled, they
should be smoothed with crocus
cloth or draw filed. After contact

dressing the contacts should be
greased ll^tly with D50H47.

4. Arcing Contacts - When the arcing
contact wipe is less than the mini

mum specified under "Adjustments",
the contacts should be replaced. The
Contacts should be inspected for un

even wear and/or damage using a
mi ror to inqiect the stanonarycon
tacts. Nornuuly it will not be neces
sary to remove the arc chutes for
this 2000 operation servicing unless
inadequate wipe or contactconditions
indicate a need for replacement.

When the arc chutes are removed,
the contact braids, coil protectors,
and other parts subject to arcing

' removed by washing in alcohoL After the

should be checkedfor possible clean
ing or replacement. Do not grease
the arcing contacts under any cir

Allow this oil to drain oH and thmi rqack

5. Check the breaker and mechanism

bearings have been moroughly cleaned, spin
them in cleap new li^t machine oil unnl the
cleaner or solvent is entirely removed.

them immediately with 6. E. Liubrlcant

OSOHIS being sure all metal parts are
Seased.
The removable seals should then
replaced.

cumstances.

a^ustments as summarized under
"Final Inspection & Test". The
necessary readjustments should be

made as described under "Adjust
ments".

overhatil or disassembly for other reasons,

or if the operation of the breaker becomes

2. Wipe all in8ulatingparts,withaclean

dry cloth, including the bushings,
clean of smOke deposit and dust,

Replace rings showing evidence

Lubrication Chart

able. However, even the finest oils and
greases have a tendency to oxidize with
age, as evidenced by hardening and dark

ating mechanism covers.

of excesstve wear.

** DS0H41 nperMdM DSOHSB.

MAGNE-BLAST BREAKERS APPLIED TO

NOTE: If

it liecomes necessary to

clean the bearings in alcohol (shellac

thinner), be sime the alcohol is perfectly

clean, and do not allow the bearings to
remain in the alcohol more thanafew hours.

U 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 witmn

twenty-four hours.

Esso Anti-Freeze and

Du Font Zerone are satisfactary for this

purpose.

Precautions against the toxic

effects of the alcohol must be exercised by

wearing rubber gloves aiui by using the
alcohol inawellventilated room; excessive
exposure to the fumes Is sometimes un-

Sleasant to personneL Washingthebearings

1 li^t ou and draining Sionld follow

immediately, then apply the the lubricant.

6. The breaker and operating mecha
nism should be carefully Inspected
for loose nuts,bolts, retainingrings,
etc., all cam, latch and roller sur
faces should beinspectedfor damage
or excessive wear. The buffer blocks
and their retainers on the bottom of

the stationary contact smport should
be inspected for possible need of
replacement.

7. The main contacts of the control

device should be inspected for wear
and possible replacement.
6. Lubricate

the

breaker operating

mechanism in accordance with the

Magne-blast Circuit Breaker Type AM-7.2-3 GEH-2003
Inspect all wiring lor tightness of
connections and possible damage to
Insulation.

10. Alter, 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
friction and that the breaker contacts

can move to the fully openedandfully

closed positions. Its electrical (der

ation should then be checked using
either the test (mblnet or the test
couplers.

B. After Every 10.000 Operations

1. In addition to the servicing done
each 2,000 (derations, the arc chutes
should be removed from the breaker

to Instruction b(x>k tolerances. This

overhaul and Inspection Is more

detailed

and will

require dis

assembly of mechanism and breaker
operating parts.

with INSTAiLATfON, ADJUOT-

as described under "Lubrication".

3. Theciqi bearingat the hinge pointof
the contact blade shoiM be dis
assembled, inspected, cleaned and
re-lubrlcated with G.E. contact lub

ricant OSOH47. Con^ct rings at the

hinge point between the contact blade
and bushing may be lubricated for

placed when reduced In thickness to
less than 1/32";

taminated by arc products should be

paper. This cleaning should be
performed any time the arc chute Is
removed. The arc chute fins should

not be cleaned. Whenever the arc
chute Is removed, loose dust and

dirt should be blown out before re
placing arc chutes.
3. The blow-out colls should be care

should be Inspected for wear.andre-

4. The stationary primary contactfin
gers should be disassembled and the
silver-plated pivot area of the con
tact and contact support cleaned and
lubricated with G. B. Lubricant
DS0H47.

5. The breaker and operating mecha
nism should be serviced as des

cribed for every2,000operations and
properly adjusted before being put
back Into service.

fully examined and If the tmniintinn
has been cracked, shrunk or eroded
from arc action and heat so that the

TROUBLE SHOOTING

sulated from each other the coils
should be replaced. All connections

will generally fall within three general

turns of the colls are not fully In

should be checked for tli^tness.

The arc runners should beInspected

-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. Checkthe stationary arcing contacts
to assure that the arcingcontacts are
In good condition and that their con
nections are tl^t

6. Insulating material that is car

bonized and Cannot be satlsfoctorily

cleaned should be replaced.

7. Any parte damagedor severelyburn

ed an(i/or eroded from arc action
should be replaced.

NOTE: Fine cracks may develm In

the fins of the arc chute sides. This
Is to be expected with ceramic ma-

toials when subjected to the high
heat ot an are and may be dis
regarded unless they are long and

Failure ofabreakertO(q;>erateproperly

classes; failure to trip, failure to close or

latch closed, andoverheating. Thefollowing
ls.a bHef outline showing^rUhular ^es
of distress that might be ^countered,
together with suggestions for remedying
the trouble:
FAfLURE TO TRIP

1. Mechanism

binding or

sticking

caused by lack of lubrication.

REMEDY:

Lubricate complete

binding or sticking

caused tw being out of adjustment.
REMEDY:

Check all mechanism

adjustments, latches, sfa^s, auxi
liary devices, etc.. In accordmtce
with mSTALLA'nON, ADJUST
MENTS. Examine latxdi and roller
surfaces for corrosion.

REMEDY:

Replace damaged coll.

be disregarded.

5. Faulty (mnnections in trip circuit

mately Everv Five Years - Whichever
Comes First

excessively worn parts In both the

mechanism and tmeaker replaced.
Such wear will usually be indicated

whenthe breaker cannotbe adjusted

erating properly.

REMEDY: Check and adjust control
device, or replace.

4. Damaged or dirty contacts In con

REMEDY: Recondition or replace
contacts.

5. Dainaged control device colL

REMEDY:

Replace damaged colL

6. Damag^ closing coll.

REMl^Y: Replace damaged colL

7. Defective

cut-off

switch, latch-

checklng switch, or interlock switch.
REMEDY: Replace defective switch.
REMEDY: Replace ol(nni fuse after
determining cause of foUure.

9. Faulty connections In closing cir
cuit.

REMEDY: Repair broken or loose

wires and see matall bindingscrews
are tight.

10. Insufficient control voltage (mused
by excessive drop in leads.

REMEDY: Inst^ luger wires and

Improve electrical contact at can-

11. Insufficient control voltage caused

by ,poor regulation (a-c control).

REMEDY:

Install luger control

transformer. Check rectifier to be
sure It is delivering adecniate d-c
supply.

REMEDY: Repair broken or l(Mse

wires and see tnatallbfauUng screws
are tight

6. Damaged or dirty contacts In trip
REMEDY:

Recondition or replace

contacts.

REMEDY: Recondition or replace
burned and pitted contacts. (C(mtacts should be recondltkmed very
(mrefully and only when absolutely
necessa^).

2. Contacts not properly aligned or
adjusted.

REMEDY: Checkall adjustments in

accordance with INSTALLATION.
adjustments.

3. Breaker kept closed or (^en for

FAILURE TO CLOSE OR LATCH CLOSED

1. Mechanism

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

REMEDY; Replace blown fuse after
determining cause of failure.

circuit

1. At this time the breaker should be
given a mneral overhaul and all

3. Control device sticking or not op

OVERHEATING

3. Damaged trip coll.

4. Blown fuse In trip circuit

C. Every 20,000 Operations or Aonroxi-

MENTS. Examine latch anS roller

surfaces for corrosion.

necUons.

mechanism.

2. Mechanism

llan devices, etc., in accordance

8. Blown fuse In closing circuit.

present a possibility of fin sections
breaking completely off. Snmii
broken corners on the exhaust end
of the arc chute will not Interfere

^th Its performance and can also

ed by being out of amustment

repacked withG.E. Lubricant D50H15

out (dUs and arc runners.

thoroughly cleaned by using sand

2. Mechanism bindingor stickingcaus

ings In the operating mechanism

should be disassembled, cleaned and

prolonged fife. The contact rings

2. All areas In the throat area of the
arc chute assembly which are con

Lubricate (mmplete

mechanism.

REMEDY: Check all mechanism
adjustments, latches, stops, auxl-

2. The trip roller and trip shaft bear

and disassembled to permit a de

tailed InspecUtm of Insiilatlon,blow

REMEDY:

binding or

sticking

(mused by lack of lubrication.

t(M long a period.

REMEDY: Operate breaker more
often to w^e contacts clean. Re

place contacts if necessary.

CEH-2003 Magne-blast Circuit Breaker Type AM-7.2-8
A. Overloading.

REMEDY; Replace breaker with one
of adequate rating tor present or
toture load, or re-arrange circuits
60 as to remove excess load.

6. Primary connections ol Inadequate
capacity.
REMEDY: Increase sire or number

6. Loose connections or terminal con
nectors.

REMEDY: Tighten.

1. Crsnk
2. Arc Oiute Remover

3. Support CaUhel

7. Ambient temperature too high.
REMEDY:
Relocate In a cooler

4. Uounting Bolee
5. Arc Otute Aeseobly

place, or arrange some means of

6. Uounting Stud

cooling.
REPAIR ANDREPLACEMEMT

The following information covers in
detail tee proper method of removing vari

ous parts of the breaker In order to make
any necessary repairs. ITils section in
cludes only those repairs that can be made
at the insbllatlon on parts of the breakers
that are most subject to damage or wear.
IMPORTANT:

UPON COMPLETION

ANY REPAIR WORK, ALL BREAKER AND
MECHANISM ADJUSTMENTS MUST BE
CHECKED. RefertothesectiononlNSTAL-

Fig. 15

Method of Removing Arc Chute

LATIOM, paying particular attention to

ADJUSTMENT and FINAL INSPECTION.
ARC CHUTES AND LOWER ARC RUNNERS

To remove an arc chute, first iy Bolt

1. Open the breaker and remove the

box barriers and side barriers (90),

contacts Fig. 17, compress and re

move the contact springs (3), raise
the contact fingers (4) and slide

13. Arc Riainer

the distance from that particular bushing
to adjacent bushings in both directions, so
that it may be reinstalled in the same
it is also possible to remove and re
assemble three bushings at one time. If

this Is preferred, alignment of the bushings
may be accomplished byplacingthebreaker

in a de-energized spare metal-clad unit

the hinged portion of the contacts.

are reinstalled.

5. To remove the stationary arcing
contact (19), Fig. 18, first remove
the arc chute as described above

and remove the side pieces (11).
Remove the screw holding the con-

tact braid (18), then turn the con

tacts 90 degrees and ffull out the
arcing conUct finger assembly.

6. Reassemble in the reverse order,
then check all contact adjustments

described under INSTALLATION
ADJUSTMENTS.

Rear Bushing and Are Runner Assemblv

barriers and arc chutes as already des
cribed.

2. Remove the upper and lower horizontal

DO NOT REMOVE ALL

SIX BUSHINGS AT ONCE.

The bushings

have been carefully aligned with the brewer
frame, during assembly at the factory, and
it is Important that this alignment bemaln-

x^SiJained to facilitate InstaUatlonofthe breaker
the metal-clad unit.

It is therefore

ecommended that the bushings be removed

and reassembled one at a time. Also,
before removing any one bushing, measure

18. Arc Runner

19. Stationary Arcing Oxitact
20. Stationary Primary Contacts

2. Remove the upper and lower horizontal

barriers (14 and 18), Fig. 13.
connection bar (13) and cup bearing(12).
4. Remove the four bolts at the mounting
flange of the front bushing being re
moved, and lower the bushing.
5. When reassembling, first mount the
bushing and assemble the ctg) bearing

(12) and contact arm (5), Fig. 17. Hie
contact surfaces at the hinged point of
the contact blade and bushing should
have a thin coating of D50H26 grease.
6. Reassemble and check all contact ad
justments outlined

under INSTALLA

TION, ADJUSTMENTS.

barriers (14 and 18), Fig. 13.

3. Remove the four bolts at the mounting

flange of the rear bushing being re

moved, and lower the bushing and arc
runner assembly.

4. For further disassembly refer to Fig. 18.

CLOSING COIL

The closing coil Is contained within

the solenoid pot (1), Fig. 19. To remove
the closing coll, proceed as follows:

Remove the bolts (8) and spring retainer

1. Open the breaker.

move the bushing (1). The stationary

2. Remove the two closing coil leads

(7).

Remove the bolts (5 and 6) to re

primary contacU (10) may also be re
moved If necessary.

5. Remove the upper and lower side pieces

BUSHINGS

OdPORTANT:

This must be done before the arc chutes

1. Open the breaker and remove the box

4. Remove the two bolts (8) to remove
the movable arcing contact (9).

16. Contact Braid
17. Blow-out Coil

3. Referring now to Fig. 17, remove the

location.

before tightenlngthebushingmountingbolts.

(6).

14. Blow-out Coil
15. Arc Runner

Disasssnbly of Upper Arc Runner Unit

them out. When reassembUngappiy
a thin coating of D50H28 grease to
3. Remove the ttvo bolts (7) to re
move the movable primary contacts

Side Piece

12. Blov>out Coil

Fig. 13.

2. To remove the stationary primary

•

10. Coil Protector
11. Class Bended Mica

GEH-2003

(2 and 11) and the Insulation (3), making
It possible to remove the arc runner
segments and blow-out colls.

6. Reassemble in the reverse order.
Front Bushings

1. Open the breaker and remove the box

barriers and arc chutes as already
described.

(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).
4. Loosen the four

nuts under the

bottom plate (4) approximately 1/2".
Support the

tnttorn plate with a

rope sling or hoist and remove the
two rear nuts.

GEH-2003 Magne-blast Circuit Breaker Type AM-7.2-3
5. Remove the nuts (8) at the top ot
the front studs.

This permits the

bottom plate, closing coil, solenoid

pot (1) and control device plunger
guide (9) to be removed.

6. To reasemble, first place the clos
ing coil and spacers on the bottom
plate (4).

Raise into position, in

serting the control device plunger
guide (9) and compreasingthepiston
ring on the upper pole piece,

7. TUt 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 pre
caution to center the closing coll

around the pole piece. If the closing
coil is not firmly held in place,

add spacers above the closing coil.

9. Replace the controidevlcetrlpplun-

ger ($) and armature (6).

10. Recheck themechanismadjustments

as explained under DISTALLATION,
ADJUSTMENTS.
TRIP COIL

To replace the potential trip coil (3),

Fig. 21, proce^ as follows:

1. Open the breaker and remove the
opening spring unit (2), Fig. 20

by removing the pivot pins (landS).
2. Disconnect the two trip coil lead

9. Plunc^er Guirir
10. ClosinK Coil Leads

5. Control Device Trip Plunger Rod

11. Cuirlc Studs

6. Closing Armetiire

12. Stop Nuts

3. Secondary Wire Cleats

wires (4), Fig. 21.
3. Remove the two mounting bolts (2)

and the trip coU support (l).

Stop Nuts

fig. 19

Closing Solerolj Asseeibly

4. Remove the trip coil (3).
5. After reassembling (In the reverse
order) check the primary contact
gap adjustment as e:q)lained under
tNSTALLATION, ADJUSTMENTS.
INTERLOCK SWITCH

To remove the Interlock switch (4),
Fig. 6, remove the two mounting screws
and disconnect the lead wires. Reassemble

in the reverse order and check the switch

adjustments as explained under INSTALLA
TION, ADJUSTMENTS.
LATCH CHECKING SWITCH

To remove the latch checking switch

(7), Fig. 8, (whenfurnlshed), remove the two
mounting screws and disconnect the lead
wires. Reassemble in the reverse order and

check the switch adjustments as e:q>lained

under INSTALLATION, ADJUSTMENTS.
CUT-OFF SWITCH

To remove the cut-off switch (I) Fig.
8, remove the two mounting Imlts and

disconnect the lead wires.

When reas

sembling, check the cut-off switch adjust
ment as explained under INSTALLATION,
ADJUSTMENTS.

1. Pivot Pin

2. Opening Spring Unit
3. Pivot Pin

Fig. 20

Opening Spring Assembly

1. Trip Coil Support
2. Moulting Bolts

Fig. 2!

3. Trip Coil
4. Trip Coil Leads

Potential Trip Coil

tfagne-blast Circuit Breaker Type AM-7.2-3

GEH-2003

RENEWAL PARTS
It Is recommended that sulficlent re

newal parts be carried in stock to enable

the prompt replacement of any worn, broken
or damaged parts. A stock of such parts

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

be carried, the amount depending tqion the
severity of the service and the time re

quired to secure replacements.

NOTE: TOe llst^ terms "ri^t" and "left" apply when facing the solenoid mechanism endof
the breaker.

ORDERING INSTRUCTIONS

!• always specify the COMPLETE NAMEPLATE DATA OF BOTHTHE BREAKER AND
THE MECHANISM.

OUAHTTTY, CATALOG NUMBER (IF LISTED), REFERENCE NUMBER (IF

LISTED), AND DESCRIPTION OF EACH PART ORDERED, AND THIS BULLETIN NUMBER.

J!f^"^ARE. SUCH AS SCREWS, BOLTS, NUm WASHERS, ETC., IS NOT
LISTED IN THIS BULLETIN. SUCH ITEMS SHOULD BE PURC^ED LOCALLY.
4. FOR PRICES, REFER TOTHE NEAREST OFFICEOFTHE GENERAL ELECTRIC COMPANY.

PARTS RECOMMENDED FOR NORMAL hlAlNTENANCE

In the teb^tion below are listed the parts of those breakerswhich are usually
recommended for stock for normal ntaintenance. Other parts are listedonthefoUowing
pages.

REF.
NO.
9
16
121
151
152
153
154
172
184
186
189
192
211
211

212
213
261
261
261
261
370
370
370
370
370
663
663
663
738
736
753
753
753
753

MVA.

AMPS.

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

250
500
ALL
ALL
250
250
500
500
ALL
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

263B292 P-2
281B708 G-1
6592346 P-2
383A903 G-1

3
3
6
3
3

6445087 P-2
6557243 P-2
236C791 P-8

6509787 P-1
6592336 P-2
6591742 P-1
17SV232 P-1
366A413 G-1
e02B742 G-3

802B742 G-4
6591644 P-7
6591644 P-8
6375521 G-1
6375521 G-2
6375522 G-1
6375522 G-2

6174582 G-1
6174582
6174582
6275070
6275070
6275017
6275017
6275017
6174599

G-2
G-14
G-1
G-2
G-19
G-20
G-33
G-2

6174599
6275017
6275017
6275017
6275017

G-6
G-33
G-34
G-19
G-20

6
24
24
6
6
3
3
3
3
6
6

DESCRIPTION

Booster Cylinder
Operating Rod Asm.

Lower Insulation (Mycalex)
Arcing Contact Asm.
Buffer

Clamp For Buffer

PrimiuT Contact Finger

Priman Contact Finger Spring

Upper Runner Insulation Bottom

Upper Runner Insulation Top
Coil Protector
Flex. Connection

Movable Arcing Contact
Movable Arcing Ccmtact
Movable Primary Contact
Movable Primary Contact
Closing Coil (250v d-c)
Closing Coil f125v d-c or 230v a-c)
Closing Coil (250v d-c)
Closing Coil (125v d-c or 230v a-c)
Potentml Trip Coil (125v d-c'
Potential
Potential
Potential
Potential

Trip
Trip
Trip
Trip

Coil 1250v d-c
Coil I230v a-c
Coil i 24v d-c
Coil
48v d-c

Undervoltage Device Coll (12Sv d-c

Undervoltage Device Coil (250v d-c
Undervoltage Device Coil (230v a-c

Coil For Current Trip (3A. a-c)

CoU For Cadacltor Trip (230v'a-c)

Control Device Coil (230va-c) Cont
Control Device Coil (230v a-c) Inter.
Control Device Coil (125v d-c)
Control Device-Goll (250v d-^)

GEH-2003

Hagne-blast Circuit Breaker Type AM-7.2-3

(2000 AMP)
Fig. 22
18

Cross-sections Type AH-7.2-3

31
30

(1200 AMP)

Magne-blast Circuit Breaker Type AM-7.2-3 GEH-2003
PARTS REFERENCED IN FIG. 22

8
9
10
11
11
12
13
13
14

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

14
IS
16

ALL
ALL
ALL

17
18
19
20
21
21
22
23
24
25
26
27
30
31
32
33
34
35
36
37
38
39
40
40

ALL
ALL
ALL
ALL
ALL

4
5

6
7

ALL
£>.
ALL
ALL
A
&
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

250,500
250,500

1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
1200
2000
ALL
1200
2000
1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
A
ALL
A
ALL
ALL
A
A
1200
1200
1200
ALL
ALL

2000
2000
2000
2000
2000
ALL
ALL

AM 7.2 (MVA)-3
258C680 P-11
258C680 P-10
215D479 P-14
215D479 P-23
281B764 G-1
265C151P-28
6442376 P-1
6442375 P-1
258C614 P-S
9915624 G-1
263B292 P-2
265C1S1 P-30
265C188 G-4
26SC188 G-S
6048229 P-1
2S8C614 G-4
258C614 G-1
2580614 P-31
258C614 P-32
26SC162 P-17
281B708 G-1
6501800 P-1.
281B739 G-2
265C170 G-1
265C170 P-S
26SC170 P-11
265C170 P-12
2580683 G-2
2360768 G-10
2580683 P-18
2580683 P-19
6597296 P-7
2360768 G-7
421A239 P-1
6442371 P-1
414A106 P-4
6441617 P-1

2360792 P-2
6442258
6442246
6441630
6442257

P-1
P-1
P-1
P-1

369A407 P-1
281B726 G-2
2580672 G-2

NO. PER
BREAKER

DESCRIPTION

Top Plate
Top Plate
Angle
Angle

1
1
1
1
1
3
6
6
3
3
3

Handle

Box Barrier Clamp

Arc Chute Support
Coupling
Block
•

Bushing (Long)
Bushing (Long)

•

Shim

3
3
6

Horizontal Barriers (Lower)
Horizontal Barriers (Ijower)

Horizontal Barrier (Upper)
Horizontal Barrier (IQ^r)

6
2

Side Barrier

3
3
3
1
1
1
1
1
1
2
2
2
2
3

3
3
3
6
3
6
3
3
3
1
1

Those Breaker Model Llet Numbers with "W" Suffix.

As Rerlng
Bearing
Screw
Washer

Washer
Stud

Bpacer
Washer

Bearing
...

Solenoid Mechanism Cover (Standard)

Solenoid Mechanism Cover (Interchangeable)

GEH-2003

Magne-blast Circuit Breaker Type AM-7.2-3

i./' ' .'i'' 'C'J*

Fig. A

Fig. B

Arc Chute Asseably with Side Cover Kenoved

Fig. 23

Coaplete Arc Chute AeeeDbly (Ref. 100)

Arc Chute (Ref. 100)

PARTS REFERENCED IN FIGS. 23A «t 23B FOR ALL RATINGS
CAT. NO. FOR

AM 7.2 (MVA)-3

NO. PER
BREAKER

DESCRIPTION

21SD4U G-2
264B100 G-8
6445050 P-3
6442365 P-2
6591756AB
6591755AB

Arc Chute Asm. Complete

6591765AA

Lower Coll

6442390
6441722 P-2
6593316 P-1
6557249 P-1
6441638
366A631 G-1
6442377
647740IDA P-13
6597401 P-1
6591B12 P-11
6591767AA
6S91764AB
6592346 P-2
6593319 P-1

247C906
247C906
6591481
247C906
6442389
6557249
6442380

P-1
P-2
P-l
P-3
F-3
P-S

Arc Chute Sides

S^cer

^acer for Arc Runner

Arc Runner (Intermediate)
Arc Runner (Lower)
Lower ^cer for Arc Chute
Core

Lower Coil Support
Insulation for Pole Piece
Insulation Tube for Core

St^er for Lower Arc Runner
Barrier for Lower Arc Runner

^acer

^ring Wast er

placer
l^er Coil (Upper)

Arc Runner (Upper)
Lower Insulation (Mycalex)
Shield

Upper Pole Piece (Lower)

Upper Pole Piece (btermediate)
latch

Upper Pole Piece (Upper)

Upper^acer for Arc Chute

^ulatlon (or Pole Piece
Insulation for Pole Piece

^>acer

6445051
6445072 P-3

Stud

6442380 P-4
6477414AC P-13

Stud

6445050 P-8
1404030

Washer

247C907
247C907
247C907
6557249
6442380
6442380
384A324
384A324
6445050

P-1
P-2
P-3
P-2
P-1
P-2
G-1
G-2
P-7

Insulation for Pole Piece

%>acer

Lower Pole Piece (Lower)
Lower Pole Piece (Intermediate)
Lower Pole Piece (Upper)
Insulation for Pole Piece
Insulation for Pole Piece
Insulation for Pole Piece

Brace ti Latch Asm. (Left)

Brace & Latch Asm. (Right)
Spacer

Magne-bUst Circuit Breaker Type AM-7.2-9

[ISOJ I6II5S II62IS9B

Rear Bushing Assembly

SldeVisH

(Ref. iSO)

PARTS REFERENCED IN FIGS. 24A, 24B & 24C
REF.
NO.
ISO
1S0»
151
152
159
154
155
156
157
158

159
160
161
162

163
164
165
166
167

CAT. NO. FOR
MVA.
ALL

180
180*
181
181 •
182
183

ALL

169

1200
2000
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL

168

AMPS.

ALL
ALL
ALL
ALL
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

1200
2000
2000
ALL
ALL
ALL

ALL

AM 7.2 (MVA)-3
175L295
175L295
383A903
6445087
6557243
236C791
175V539

G-9
G-10
G-l
P-2
P-2
P-8
P-1

6442369 P-1

NO. PER
BREAKER

DESCRIPTION

Bushing & Arc Runner Aam. Complete

Bushing Sc Arc Runner Asm. Complete
Arcing Contact Asm.

3
3
6
24
3
3

Buffer

Clamp for Buffer
Primary Contact Fingers
Spacer

Arc Runner Filler Plate (Upper)
^acer

6477401AA P-29

6591755AB
6591770AA

I^per Arc Runner (Top)

6
9
9
9
6

Coll No. A & B

6477415 P-3
6441638 P-1
6441722 F-1
6442370 P-2
6442368 P-1

6591756AB
6597401 P-i
6591612 P-5
456A302 G-l
6S91750AB
175V230 P-1
6445085

6509787 P-1
175L295 P-50

Nar.Wash. 1/4-20
2S6C761
236C791
236C791
6591812
6592331
363A904
176V932
6591787
6591737
2650187
265C187
6593317
6597402
6592336
6591738

P-20
P-3
F-4
P-15
P-2
G-2
P-1
P-l
P-2
G-a
G-9
P-2
P-1
P-2
P-1

3
3
19
24

Groove Pin

kiaulation Tube for Core
Core

Spacer for Arc Runner

Arc Runner Filler Plate (Intermediate)
Upper Arc Runner (Intermediate)
Spring Washer

S^cer

Coll No. C

l^per Arc Runner (Lower)

3
3

Insulation

Arcing Contact Barrier

3
3
3

Spring
Spring Guide
Washer for Spring Guide
Retainer for Primary Contact Finger
Retainer for Primary Contact Finger
Retainer for Primary Contact Finger
Bushing
Spring Retainer

24
24
24
3
3

Contact Siqtport Asm.

Upper Runner Insulation (Top)

175L295 P-117
432249
175V232 P-1

188*

ALL
ALL
ALL

18
3

Washer
Coll Protector

2S8C666 P-4
366A413 G-l

Bushing (short)
Coll Siqjport
Cover

Upper Runner Insulation (Bottom)

Magne^blafit Circuit Breaker Type AM*7,2-3
21 i 220 213 212 213 212 2i7.2l6A 220 211 213 212 213 212219

Maene-blast Circuit Breaker Type AM-7.2-3

PARTS REFERENCED IN FIGS. 26A, 268 & 26C FOR ALL RATINGS

(»

CATALOG NO. FOR TYPE
REF. NO.
324
325

326
327
326
329
330
331
332

AM 7.2 (MVA)-3 A
236C769 G-1
6442255 P-1
2360769 G-2
6509728
6477427AA P-9
6443714

6477427CA P-2
6597228 P-1
236C769 P-9

AM7.2(MVA)-3 0
236C787 G-1
236C787 P-12
2360787 G-2
6509728 P-1
383A926AD P-1
2360787 P-14
236C787 P-S
2360787 P-16
2360787 P-6

NO. PER
MECHANISM

DESCRIPTION

Plunger Interlock, Complete

1
1

Plunger For Interlock

Spring For Interlock

1
1
2

Pin
Roller
Pin
Crank
Front Guard

Bracket For Interlock

A This plunger interlock frame Is wider than the mechanism frame.
0 This plunger interlock frame is narrower than the mechanism frame.
23

GEB-2003 Magne-blast Circuit Breaker Type AM-7.2-3
zes

-I—T

[SEE VIEW 6)
[SEE VIEW
(SEE VIEW B)

Conplete Spring Assenbly (Ref. 273)

ie-i3 Hechaniso for AM-7.2-3

Magne-blast Circuit Breaker Type AM-7.2-3 GEH-2003
PARTS REFERENCED IN FIGS. 27A, 27B ti 27C FOR ALL RATINGS
REF.
NO.
250
251
252

253
254
255
256
257
258
259
260
261
261
261
261
262
262
263
264
264
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
290
291
292
293
294
295
296
299
301
302
303

304
305
306
307
308
308

CAT. NO. FOR

AM 7.2 (MVA)-3
6443518 P-1
258C608 P-6
258C608 P-7
215D470 G-54
215D470 G-55
6551742
258C604 P-8
6192382AB P-1

21SD470 G-61
281B711 G-1
258Ce09 P-1
6375521 G-2

6375522 G-2
6375521 G-1
6375522 G-1
236C796 P-6
296C796 P-7

6591632 P-1
236C79S P-4
296C795 P-5
2360796 P-12
414A109 P-4
236C796 G-2
236C796 P-8
383A926AE P-1
258C630 P-7
2S8C630 G-3
2580630 P-8
414A109 P-8
258C630 G-1
4S6A808
456A807
258C630 P-3
258C630 P-5
258C630 P-4

383A926AF P-20
2580630 P-9
2580611 P-1

2580611 P-11
121A7436 G-1
421A256 P-1
21SD470G-S3
21SD470 G-S2
2580611 P-3
414A110 P-1
414A112 P-1
215D470 P-16
6509799
414A110 P-3
6477097
2580609 P-8
104A2474 P-1
421A210 P-1
2580608 P-3

2580611 P-S
25BO609 P-9
421A209 P-101

2580609 p-6
" ~"P-39
421A208

NO. PER
MECHANISM

DESCRIPTION
Shaft
Crank

Latch
Crank
Link

Spring

Spring Clip
Veeder Counter
Unk

Indicator Assembly
Prop

Closing OoU (125v d-c or 230v a-c) 250 MVA
Closing Coil ll2Sv d-c or 230v a-c) 500 MVA

ClosingOoU (250v d-e) 250 MVA

Closing OoU (250v d-c) 500 MVA
Plunger 250 MVA
Plunger 500 MVA
Piston Ring
Pole Piece 250 BIVA Pole Piece 500 MVA
Guide for Pole Piece

Washer
Arm Plate
Stud
Pin
Clevis
Plate
Rod
Buffer

Complete Spring Assembly
Inner Spring

Outer%riim

Spring Retainer

Retaining Plate

Spring B^se
Pin
Bracket
latch Shaft
Stem Bar

Trm Shaft Bearing

Spring
RoUer
Link

Prop Pin
Pin

Trip RoUer Bearing
Spacer

Spring
Pin

Prep Spring
Pin
Pin

l^cer
Latch Guide
Pin
Pin

Magne'blast Circuit Breaker Type AM-7.2-3

m'rir T

mmamrn 357

•23359

i^U362
'-^^*-356
I.I.H259

HS-13 Hechanisa for Type 7.2-3 Breaker

PABT8 REFERENCED IN FIGS. 28A, 283 L "SC FOR ALL RATINGS
REF.

Man. Trip Rod Siqiport

236C795
236C795
174V394
174V394

857
358
359
360
361
362
863
364
365

25O,250A
500,500A
250,250A
500,500A
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
Not Shown

ALL
ALL
ALL
ALL
ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

Insulating Tube
Aux. Switch

258C609 P-4
456AB76 P-4
236C788 P-6
104A2476

Crank

236C788 P-3

Interlock Prop

258C601 G-3
25BC601 P-15

Bearing Bracket

236C786 P-8

236C7BB P-30

Link
Crank
Crank
Bracket

4S6AB66 P-1
456AB66 P-1

Interlock Switch

236C78B P-7
2S8C601 P-16

6174582 G-1
6174582 G-2

^acer
Interlock Prop Shalt

^rlng
Shaft

Latch Checking Switch

Potential Trip Coil (125v d-c)
Potential Trip Coll (250v d-ci

6275O70 G-1

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

6275070 G-2
Z15D470 G-5

Potential Trip Crank

6174582 G-14

Potential Trip Coll ( 48v d-c)

left Side View

Magne-bl26t Circuit Breaker Type AM*7.2-3

GEH-2003

%
r'.ij.

wt.-rSr-r^-v.

Maintenance Closing Device (Ref. 510)

Secondary Olaconnect Device (itef. 500)

PARTS REFEREMCEO IN HGS. 29 6 SO

CAT. NO. FOR

AM 7.2 (MVA)-3
802B79S
802B79S
2&4BX73
2MB173
366A234
36QA234

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

Secondary Disc. Dev., complete: 16 point
Secondary Disc. Dev., complete: 16 point
Secondary Disc. Dev.,complete: 7 point
Secondary Disc. Dev., complete: 7 point
Contact Nut

Contact Nut

Plug

Lockwasher for Plug

3663094 P-38
6505244 P-1

Spacer

2S8C669 G-1

Maintenance Closing Device

Socket

GBH-2003

Magne-blast Circuit Breaker Type AM-7.2-3

Partial View of MS-13 Hechanin with Current Trip

Undarvoitage Device (Kef. 6Ung
Trip Arm
Spring

Coll (I25v d-c)

CoU (230v a-c)

Coll 250v d-c)

Magne-bUst Circuit Breaker Type AM-7.2-3 GEH-2003

Fig. 33

Impact Trip Device for All Hechanisoa (Ref. 702)

PARTS REFERENCED IN FIG. 33 FOR ALL RATINGS
CAT. NO. FOR

AM 7.2 (MVA)-3
6S94553AA

6591817 P-1
6591388 P-ig

6076403 P-315
6477425BA P-3
6076403 P-311

6592554 0-1
6557106
6558791
6509706
6443516
6557105
6558746
6558747
6076401

Impact Trip Device Complete
Lever

Locking Plate
Pin

RoUer
Pin
Crank

Adjusting Screw
Eyebolt Asm.

Spring
P-1
P-1
P-1
P-315

6477401AA P-8
6509794
174V378
174V378

6443666

295B227 G-3
6502505AA
6558752 C-1

6558751 P-1
6049320

6557068 P-9

6076401 P-385
2236575

4905058 G-4
6443667

6174599 G-2
6174599 G-6
4S6A334 P-l

Coi^llng
Bracket
Switch

Frame Assembly
Core Assembly

Angle
Felt Washer
Pin
Pin

Guide

CoU Frame
Bracket

Coll for Current Trip 3 Amp. a-c

Coil for Capacitor Trip (230v a-c)
Rubt>er Guard

GEH-2003

Magne-blast Circuit Breaker Type AM-7.2-3

Fig. 34

Control Device (Ref. 750)

PARTS REFERENCED IN FIG. 34 FOR ALL RATINGS
CAT. NO. FOR

Control Device, 125v d-c

403A128 0-1

Control Device, 230v a-c (Continuous)

6375988 G-6
6375988 G-9

Control Device, 250v d-c

295B227 G-2
295B227 G-1
6275017 G-19

6275017 G-33
6275017 G-20
6275017 G-34
6591455 P-1
6442392 P-1
6591411 G-1
6591450 P-1
6412255 P-1
6412251 P-1
6591440 G-1
6592161 P-1
6592162 P-1
6477041 P-1
6591412 G-l

6591404 G-1
6272844
365A458
6370699

6477063

Control Device, 230v a-e
Auxiliary Switch, Top or Back
Auxiliary Switch, Top, 230v a-c Only
Coll, 125v d-c
Coil, 230v a-c (Continuous)
Coll, 250v d-c

Coil, 230y a-c (Intermiltent)
Support for Contact Tip
Insulation

Support for Stationary Contact
Core
Blowout Coil

Support for Coil
Connector

Siqiport for Movable Contact
Shield

Spring
Movable Contact

Arc Chute Assembly
Spring

Spring (a-c Intermittent and d-c)
Spring (a-c Continuous)

^ring

GENERAL BKTRIC SALES OFFICES
MAWtoassbitoi;...
AISU

ISY tOCAft O^CIUTIQMS

t-...«««.-•••

BtiueMOli*4«*"

M • UATla* * (Mmm rictftci** Sri**
• • aMUUMtMMitMWtMClVWMnV
O -

•lmli0*e«W..tlSlBl*«**dAw.
Itattavtm SS4CI. Mitt m•****» Sk«? ioi

OMttaaMCO19409 ... BSIOaOdlHAva.
I

0080 BIOS.BialfiaCaeM
Ki^igan010*4... U10K.BIKW44 M.

AV
AISU
A

KmmIUo 91091. IMlMaMaKAw.M.W.
H««wkU OHIO...« 1901 AlPMM DM.
MvrtrwMoM 911M. til M.«. BiMO BL

Atf
C
u

Ot*BMM19890 . . . 901 MaMBbtbat

ttedntilo 11209... tinWMtMBUf.
HaaOfttI*91M4
atMBMooDrlw

tboab
$V
ou
AISU

AfelMMTIOei
44IC4«arBL
AaMfUlo 19181
OOOPMfcSL
BMMMAl 11184..... .IMO CU*4r Aw.

CarpM Csnatt 10481
jOOtCOBoamlM.

ACISU

ealUs1«41...ll018l«BiWSrWMwar

ISU
A

UPaMlOOOl
tUICittMMSb
apaaoMOCt
SSMICttaMMSt.
A
Nn OMnAlOIST
t08M.lM«.Dr.
SO
ACISU MawlMlien....*4118BIiObmIAw.
I iBMlS 10400

HtfUl ClaM* 44tM

Also

SaMtakaCl^ 84110.. MIS. IMMBSL

vcMooi'r

umaad 00189

JO 1/9 C«4ar St.

BMO ttMsM* Aw. K.4M MKtw A* ..

ami
AISU

KeipMtiuvatlOOl
lllMaaaSb
aicawM 9*198.. ISO*WiUo* U«a Or.

Also

llMaafc*94810.. .MUCaUaaal AW,S«

AB V
AI
U

CtiaheeeCii? 19104.MMCta*t«a ftlw.
ThM*14101 ...... 0199S.P«««e Av«.
TwiMtilOS
«Mt4M»SI.

Tclaa 14101

P.O. BM 1*44, SwOulOvSUMoR
TMaa 141*0
B 41tt puc*

BmAMuu 10984 .... 4lOB.MatoAw.

44*01.. 913 C.Udwaata A«c.

tekaOM 4*119
oat Bfran Aw.
CillOii in*1
IllOMarwitA
Oai««o414M.......MMS.DUM t(«y.
Maaafind 44008
1Mp»n(Aw..w.

28k 1/2 iMMlA AW..W.

uesisstpi^1
P.O. Bm 99
c«up»n IHH....
u
JachaM 90104.... . 999 M. Mart Plua
AS
JmKmaIOMI.. PW.T11 SlwlrtcDMl.
U

4ie*we*Aw.
.119 UMwraltO Ot.

ACIBU CiMiMaa41900....toilVkaBrrPPn.
c
OcwIaM 44110. BOOMCwkwAMC* PA
AIMSU C9*wtU044IU....9nNUkKCid«Aw.

MAAIXAND
. ^
ISO
SalOMrcSUOl
l|I.CMrla4S4.
AU
OaiMMtt tuea.. tOMIWIacopMCtftI*

OrweviUv 90000 .... Moo

Aimg Attaay UMI..•»•*' CoBp"**Bf.Wvn
V
fiifMBiii rtn
4epv«M*-

AMuMtm IIMI.. JOOl MMAfllHV Or.

IIM OyM SI.
102SM.BttUlSl.

Affiiiirova

fCCW TOKK

UlMAM(«10«0«...Mim»rMABlvd.

«UK«e^ ITMI .... 9980 fM AW.
TOrOWtl
mtS.MaMnil.

RiBvfSt.

CaatOtmsv OMII. M aioloM* GuOcm
wtttara 0104S
1SC.Wiiib»M.

Pta*w-tktMt9 ... leOOMAw.BMS.

...teosputuvo.
IMdhtaMA.

M»Ptm«a.

c
AtSO

ruwoo
AtMBO
c
AlO
At
0

. . . «M M.t!*« ftfMawcfe OOMt . . . 9 Uwaacs Bu

• iflMiWM mat.

BOlOakBMM

•PMUddpMA MIS4 . .9848 Be* Brt* Aw.

• tlecincaUMeciatcalSMwSaap

3-60

VASKWorgH

genekal Euatic company, philaoelphia, pa.

WBOOttW

•MBSMmI KaMdOA 94818
.....••.•••...••a itmi
cICUw^ 11989 . tMW.fBtlMl Aw.

PDS/ERfiM MERRILLVILLE: IN

P.1/10

RENEWAL PARTS
MAGNE-BLAST CIRCUIT BREAKERS
TYPES
AM.7.2-250-4

1. Always spacUy the completa nameplate data a( both the breaker and the mechanlam.

2. Specuy the quantity, catalog number (it lleted), reference number (U listed), and description of each pact
order^, and this bulletin number.
3. Standard hardware, such aa screws, bolts, outs, washers, etc., Is not listed in this bulletin. Such Hens
should be purchased locally.

4. For prices, refer to the nearest office of the General Blectrlc Company.

Wfiair •rUafiHw ramwal parh. givi euwiUlTf (•!••••,nwnbarf

«incrl|ill«n

•ath !>••» Weelrae, •TtU

GENERAinliECTRIC
e«H i»k|«tl 10 UnRso mIAowo Rorln.

PDS/ERRM MERRILLVILLE IN

NO.225

P.2/10

TYPE AM-7,2 MAGNE-BLAST CIRCUIT BREAKERS

Gef^sa

Type AM'?.!! Breaker (Refer to Fig. 1)
Catalog Number for Type AM'7.2

AU
AU
AU
AU
AU
AU
AU
AU

AU
AU
AU
AU
AU
250

' B
9
10
10
11
11
11
11
12
12
12
12
13
14
IS
16

16
16

17
17
18
19
20

21
22
•23
•23
•24
•24
25
26
27
28
29
26

AU
AU
AU
AU
AU
Alt
AU
AU
1200
2000
All
AU
1200
1200
1200

500

AU
AU
AU
AU
AU
AU
AU
AU
AU
250
500
AU
AU

2000
1200
1200

2D0O
2000
AU
All
AU
AU

AU
All
AU

AU
AU
AU

0
AU
AU
AU
AU
AU
•AU
AU
AU
AU

78S.025BCQOaOP10

AU
AU
AU
All
AU
AU
AU
All
All
All
AU
Alt

A. B
A.H

oosBcoeaiPooB
osaecoisipoaa
QB36C018OF0ia

—

Top plate
Angle

Box barrier eup

Arc ehnte support (rtght)

Arc chute airport (left)
Arc chute supinrt
Arc chute eUsip

0802807646001
023BB02028002

oasscQoasGOoa
aBS8C0628F005

0868606836008
0968008288006
0959006288008

3
3
«*

Shim, 0.0D41a. thick
Shim, 0.010 In. thick

OBSacoeaaFoos
GB8BCDQBBF020
068SCOS86P081
^

—

0182027888004
0182027388006

026SC016aF017
O281B0708GOO1
oeaecosBBFOi?
026SC0176G002
0265Cai7BG001

Horizontal barrier (lover)
Horizanfel barrloi' (lower)

6
3

Horizontal barrier (lover)

Horizontal faarxler (upper)
Horizontal barrier (upper)
Borlzontal barrier (upper)
Horizontal barrier (upper)
Operating rod Baeemfaly.

Front wheel and caster

04S8AQB628O01
00B607296FOQ7
02S8C8768G007
0888802826007

OOBS972S8Pa87

Hbrlrootal barrier (lover)

0107898488007
0107898488005
0107898488008
Q46SAQ8eaFOpS

04SBA08B2PQ08
04B6A08a2P001

6
8
6
6
3

,02aiB07Q8GOPI
0668005888017
qr

0107BBa4BPOOT
OI07B9a48PG05
0107B93IBPOD2

0258006148082
0266001628017

Hide barrier
Cbiuiectlon bar

Box barrier Bimport
Box barrier support

Box barrier support

Wheel and spanner bushltiR

2
2
3

Wheel
Front wheel and caster

oBBBBoaaaraoe
0898802826001

0898802826096
OB99BO292GO01
0064422678001
03B8A040T800I
0414A010BFOD7
0064422468001
Dia4Aa49BP0pl

3
3

Hinge point assembty.
Hinge point assembly

03a9AO40TP0Ol
.a4i4AaX0BF0a7
0064422488001

0104A2495Pq01
a4S6Aoae488pi

0137A9iaB8002
0421A0239P001 '

FiB> 3. Arc chuts (confd.)

PDS/ERflM MERRILLVILLE IN

NO.226

P.7/10

type AM-7.2 MAGNE-BUST mCUIT BREAKERS

ABC tiBOTB ASSEMBLY (Refer to Fl^ 3)
Bef.

Cat. Xo. for I^pe AM'7. i
-4

-6B

Keq'd.

100
101
102

73S>08iaX02UGQOS
0264B0100G014

799,.0ai3Xa216G012
08B4B100001T

ail4C549SS002
an4C548SG0O4
09BZC07SDP—8
oseaciyTDiGOOB

Lowet; brace

O114CS40SGaO3
0114C849SG(I04

0108B1S43P002
oeascosBflpois

^^A^'retSwd'
* Not illustrated

3
8
3
3
3
6

01S2A873BG012
0132C2738F001

QB62C07SOP010
O962CO7E0P0Oa

0414A0102P008

0414A0108POOB

Upper pole pieces, left

Upper pole pleees, right
Bear brace
Core

Core, 2 ll/lB In.
Core, ssAetn.

Core Insulating tube

Core Insulating tnbafor 2 11/18-ln. core

3
3

Core inaulatlng tube for 3 3/16-in. core

3
3

Spacer
A/C support, right

Spacer (6/32 in.)
S^cer

aSBBCQSBSPOlB
0137A916SP00a
O0B17S1OBF089

042XA02O8P497
0265COZ50F015
0862C0730P003
OSB2CD750P002
0285C0163P008

O456ADBe8P0aB

oia7Aoieapoo2

OOB1761D8PP88
0421A0208P4B7
026SC01SOP015

^aeer
Bushing
Spacer (S/4 In.)

oaB5C0168F008
026SC0163Ffl09

0414A0ig4P0O2
0414AQX9BF001

6
6

Upper coil support
Bairler

QBiaXoifiepopi

6
8

Myealex, upper shield

Q2B5C01SOPOia

Spacer
Spacer
Spacer

02BSC01BOP01S
04X4A01S6P002
a9S2C0730P007

04l4AO19ePD02
09S2C0750Pa07

•

Upper pile places, ri^t

0619C0484FOOB

aQB442389F004

Vpper pole ^eees, left

DB19C04S4I>aog

0456A0S8Bp(H]6

9de brscO

a061676108P070
0421Aq208POS9
a084422B9PaQ3

Upper pole pieces, left
Upperpole pteees, ri^t

3
a
6
12
12

0431A0apBP08a

left
rlsM
left
right
left
left
left
right

Upper jmle pieces, left
Upper pole pieces, right

OSQSCaTSOFOlO
Q9B2C07a0P009

Lower pd}e plpceB^
Z4iw«r pble plms.
Lower pole pieees,
Lower pole pieces,
Lower pede pteees,
Lowell pele ^eces,
Lower pole plepes,
Lower pMe pleceak

3
9
a

O132Ca7S6G0OB

OOB446030F010

Lowerpole pieces^ (eft
lo?er pole pieces, rifliit

Upper pole pieces, right
Upper pole pieces, left

0132027366001
0132627366003
0ia2C2736G003
C1S2C2736G0O4
Oia2C27S6COOS

oasacosiBpozs
D25BCQB36F0aB

V|iper support
L^r support

0688C0589P014

121
122
123
124

*129
130
•131
132
133
124
136
136
137
138
139
140
141
142
143
144
14S
148

8
3
a

osBzcaToiGOoa
0114CS304G002
0U4CS30BLAST CltlCUtr BKAKKItS

0.5/10

GEr-4495A

A&C CBUTET ASSEUBLY (Refer to Slg. 3) (Cont'd)
Cat. No. for Type AM-7.2

Ref.
No.
147
148
149
160

ISl
162

163

733-061SC04B6F005
D6iacO489P0Qe
0414A0196F001
025BC0616F011
^265001506006
06iaC0400G001
oaescoissGooa

159
153

164

0265C0196O0Q8

155
166
157
156
IBS
160

026BGO155GO0B
O414A0116P00a
O414AO187;p001

161
162
163
164

Lower eoll eapport, left

3
a

Lower call anpport. right

0266001556003
0266001666008

a
3

CoUt upper
OoU, t^per
CoU» upper

0269C0B7660&2

Ceil, lower

0266001956008
010BBS580P001

6
3

CoQ, .lower
Rindatton plate

Q414A0197F001
a414AfllB7F00a

3
3

Shim

0132Ca74SF0ll
03B8C06ieF011
01SaC2746G0Q8

Xneidatlon aeal
Xtoner

sum

Rnnpar aeeemhl;
Runner MsemUy

Q26SC0154G0D9

O265CO164C00B
QdSSAOBBBFOOS

6
B
3
9

0421A0806F02a

12 •

Q421A02qBF017
ooBnBioopqpe

24
36
6

0456AOB8BP003
042lAa2018F02a

*172
173
174
175
*176
177

O138Ca7OBF00B
0132027466001

0265001546005
0266C01S4G001

Q421AOa08F017
QOemiGSFOOB
O456A03a6F001
04S6AQB01F210

165

0414A0197FQ02
026SC0154G003

-49

006176109FOB4
0481AD201F001

OB02B0726F001
odSOAOBeiPioa
010BB1B43F003

0456Aa801PaiO
04S6AQ891P020
01S2C270BG002
026BC0ieiFD17

O4l4A0iaiFQO4
04S6A0BeiF20B

04aiA020iF0ai
DB02B078SP004

0132027376003
0132027276004

Runner asseniMy
Runner awtembly

Spacer (3/4 (n. lonp)
Spaoer (21/32 In. loniO
3paeer (17/32 in. long)
Spaoer (5/32.In. long)
ZiiDwer ronOer liarrler

Lower runner aUeld
Lower runner Inenlatten

SUUd and cooler assembly, right
Shield and cooler assembly, left

MftY. 5.1998

10:06fiM

PDS/ERfiM MERRILLVILLE IN

TYPE AM-7.2 MAGNE-BUST CIRCUIT BREAKERS

GEF-443SA

213 212 213

219

A. 2000 omp. oil MVA rdlng.

B. 1200 amp. 500H e) 2E0A and 250H

dosing coll (250v d-ej BOqH

Closing coil (126v d-c, 1307 a-e) 500H
Closing coll (125v d^c, 290v a-c) 600A
Closing qcdl (126? d-e) OOOA
Plnnipr, SDOAaodSDOB

FlungsPr 200a, CQOB

0962007000002

Pole piece, 260A, 250H

0962007000012

Pole piece, BOCA, SOOS
BuHcir
Anadture plate
Stud, 250A sad 2508
ttud, 600A and SOOH

0236007980002

0236007968026
0296C07BBP008

0137A6066PDa2
025BC0630P007

02SBCQB30P031
O2SeC0B3OF00B
0414A0109P0G8
0256006300001
OBSBAOaOB
D466ADBaT

02S8C0630P003
O23BC063OPO0S
0268009300004
O137AB0B7P02O
0259006308002

. 02SBC0611P001
02S8COB11P002
D25aCQBllP011
0121A743BG001
0421A02E6

Pin
ClevlB

Plate
Rod
Bntfer

Complete epxing assembly
Inner spring
Outer spring
^ring reCnlner
Retaining plate

Rprlitgbasa
Pin
Bracket

Latdi shaft (2608 and SOOH)
Latch shaft (2S0A and SOOA)
Step bar
Latch shaft bearing
Spring

02SBCG60BP()04

Cranit

287

0215004700063
0215004700052

0486A(IB76P]03
008509790
0414A0110P003

Spacer
Spring

008477097

Prop spring
Trip roUer pin

206

292
293
294
285
236
299
301
302
303
304
305

O2S8C0608PQO3
O2SBC0B11PO0S
09SaC0897POD4
0481A0209P101

0619004788019
006442239PQ01

Bearing, 2S0A and 2608

006442239FOP3

Bearing, SOOA and SOOH

0236CO79SP026
oaSBCOBllFOlS
0236007958075

Armetore
Cover lor opening spring. 2S0A and SOOA

*311

312

^.^Oider 0414A01'09P010 tor 2-1^ inch O. D. baiter
Order 0414A0109P012 tor 3-3/4 Inch O.B. botfer
'Soc illustrated.

A 7, MS*13 mechanism
MS-ia Mechanism CBefer to Fig- 71
No, Par
Cat No.

350
361
352
352
353
353
354
358
353
359
360
362

363
>364
369
367
369

•363
>970
371
371
371

7a3-oas8Coeo4Goa3
oasacoBoapooa
02SSC07BSP04Q
Qa95C0765FD41
0174V0S94P0q3
0174V03S4P004
006445053
i
O45SAOB76F004
OaSBCOTBSCOSO
0137A912fl ,
0256CaB01G003

O23eca78BG0Ba

O23BC078BP00S
0236C0TaBG054
a2SBC07BBPD34
D4SBA0866P001

0456A08e8P001
D456A0BS6PD0a
0061745820001
OQ61745B2GC02
0081745820032

371

00627507QCD01

371
372

OQ6273070GOD2
T 0215D0470C005

DeSBrlrkJon

Mechanism

Manual trip rod

bbnnaltrip rod support
aSOA and 250fi

Rod, 5D0A and 50DK
TUra, SSOA and 250K

Tube, SOQA and 500H

Insuliddng tuba

Auxiliary switch
Spacer

Intertoek prop assembly
Spring

Bearinf bracket
Roller and link assembly
Llrik

Roller assembly

Bracket

interlock switch
Latch check switch, when used
Cut'OR switch, 3aOA and 500A

Potential trip coll (I25v d-c)
Poteisdal
Potential
PolcBlial
Potential

trip
trip
trip
trip

coil
coll
CoU
ooil

potential trip linkage ^

•Not illustrated.

jAtefer to breaker lor proper ntodel.

(250tf d-ej
(ZBOu a-c)
<24v d-e)
(4av.
.

Type SBM - Order cat. No. Oia7A9192GD03, Type S0"ia —Order Cat, No. 01STA9192C0U,

MftY. 5.199B

10:05ftM

P.4/10

TYPE AM-7.2 MAGNE-BLAST CIRCUIT BREAKERS

GEF-4435A

NO.226

PDS/ERflM MERRILLVILLE IN

Fig. 8. Stcendaiy dlieetwOlng dawiea (ll«f. Ne. SOO)

Flg> 9. Malotinanc* dutne davfea (Raf. No. 510)

SecoB^tey DiseooaKct Device ud Molntenanoe Closing Device (Eteler to Figs. 8 and 0)

733-0802BQ7BaGOO$
0264B0I73G0Q3
Q06n99S4P002
000S4S763P0O1

ossacoaesGOQi
OSBSAOaSdPOOl
OS66A0234P002
03B6A02MFD09

Deeerlptlon

Seeen^aiy dlsconnset device, complete, 16 points

Eeconduy disconvect device, cotnplate, i points
CoTitafit plug
Lockwadier lor contact plug
Contact socket, 16 point
Contact socket, 7 point

a
1

Contact nut for Ko. B vlre

, t
t

Contact nut lor Xo. 14 wire
Contact nut lor No, 12 wire

Mflintimasce closing device

- Not Illustrated.

IA total of 16 contact mils is used on the 2&QH and SOQH breakers and a total of 14 contact nuts Is used on the 250A and 5D0A
breakers. Order size and qaantity of contact nuts to correspond with, the size and quantity of vrires entering the secondary
disconnect device.

PDS/ERflM MERRILLVILLE IN

GEF-448BA

TYPE AM-7^ MAGNE-BLAST CIRCUIT BREAKERS

Rb> 11•

Flfl. 10. Partial vlaw of MS-13 machanism

P.8/10

Undarvaltoga dawk* (Raf. No. 647}

wilh curranMrip

Qtfffer to PIsB. 10 a&d 11}

CeBezi{iUaB

Cat. No.

Spring
Trip pan
Bracket
Trip latch

73^•006B6172SP001
oaesAOBiiGOOi
OOe5SB7«BP001

00607 e404Pai3
OZ18X0185G001

AC undervoltaga derica (Icsb coO)

0213X0217C001

BC undBTVoUage device (ieiia coU)

0175VOB74P001
oa66A044SP001
006S51726FDD1

Stop for d-e device only
Spring for d-e device aatj

for B^c device only
Pin lor d-c device only

0175V0578P001
OQBD7B4P1F300

Pin for a-c device only

ooBOTe40iPaos
029SB02a7G002

Switch

Pia
Bracket
Sttlni for d-c device only

017570676PQI)1
0374AOa46P001
O176Vaa62P001
03B4A03SOQ001

Link arm asm.lor d-c device only
Stud

. GlSTAeOSSPOSO

Coupling

QQB5S8711P001
0065687230001

Trip arm

QOSSOS79BP001

Spring

CoU U2Sv d-c)
Coll I230v a-cJ

0OB275017qO19

I 006275017Q039
0063750170020

CoU (2«0v'Ae)

;«,7

Termli^l Wrd (6 pqit^

' 0664006420001
• Net Uiusbued.

PDS/ERflM MERRILLVILLE IN

P. 3/10

TYPE AM-7.2 MAGNE-BLA5T CIRCUIT BREAKERS

Pie- 12. Impqer trip davic* (Raf, No. 703}
Imput Trip Device (Reler to ng. 12}

Cat. Ko.

TSS-OZiaXOlOOGOOl
QOeS91B17P001

0065913e8?0jg

Dsecrlptlea

Impact trip davlee, complete
Lever

LocUag plate

006076403PaiS

Fin

OX37Ae064POOS
00607&4QaP311
0069925540001
0O6B67108POO1
006SS87910001
0161A5&31P001
OOe443516PQ01
0065571097001

Eyelmit assembly
Spring

Jacket
SiBcer
Bracket

00855B747P001
0060764(^7318

Trip arm

0137A604BPQDa
006509704PD01
0174VOa78F001
01T4V0373P001

SEaesr
Spring

OOe44306SPOOl

Bracket.
Switch

D293B0227G003
OlO7B9a0SPO0t

006698752G001
OO65S8751P001
ooeofBszopooi
DO65S708aPO0d

00607 &401P385
00223e51SP001

00490SOBaG004
. 000443a6TP001

0061745990002
0O6174B99C006
04S6AOa34Paoi

Rod

Coupling

Frame assembly
Core assembly
Angle
Felt washer
Pin
Kn
Guide

Coll frame
Bracket

Current trip coll, O.ampa-c
Capacitor trip eoU (aspv o-c)
Rubber guard

MftY. 5.1998

10:ism

NO.225

PDS/ERRM MERRILLVILLE IN

P.9/10

OB7-4436A

TYP8 AM-7.2 MAGNE-BLAST CIRCUIT BREAKERS

Fig. 13. Cenlfol dtvlw foi* oil mwhonUw* ffof. 750)
•»CoM3"ol Dsvlee HflchanlBin (RbIw ta Fig. la)
Rel.
No.

00837BBBaGOOB
0D63759BBG00B

250
250

0403AD226G002
0409AOS24G003

Control devlao U95»'
Control doviM (126v d-c)
Control dwlca (2B0v d-c)

Control derico (gsOra-e) (intermittent)
Control device (2307 s-c) (inbermlttenl)
Control device (2307 Br.c) (intermitteirt)
Conta-ol devi<;e (230va-c] (continuoue)
Control device (330v a-c) (continuous)
Control device (2307 a-e) (eontlnaouo)
...

AuxUlsry soltel^ top aad.teck(125 and 2Bv d-c)

761

All
All

O29SB0a27C002
OZS9802270001

AuKiliary BuiUch, top (230v a-o only)

0002750170019

0002760176020
0002750170099
O0S275O17GO34
0006014068001

0084499628001
006S914110001

0065914508001

Supportfor contact tip
Ins^tlon
Support for statlonac; contact
Core

0064192518001
00eS9l44OGOOl
00059I440G001
OQ6SB1440G0D3
O0SS91440G004

Connector (126v d-e, 250v a-e) (Intermttteirt or ^inuenis)
Conneetor (2aOv o-e) (intermittent or continuous]

762
763
764
765
766
767

AU
All

0064770418001

767
769

006272044
0365A04S8
006370699

CoU (230v a-c) (contlnuouB)

Coll (230V a-c) (Intermittent)

Blowout coU

0000921618001

CoU (1207 d-c)
Coll {250v d-c)

0064122BSP001

AvKlllary switeh, bacls {330» b^c on^)

OD66021628Q01
0QeS9l4lSG00l

0065914046001

SuplDTt for coll
Connector (2B0v d-c)
Connector

Supportlor Rvovnblo contact
Shield

Spring

Movahle coptact
Are chute aaeembly
Spring

Spring (a-e Intermittent and d-c)
Spring (a-c continuous)

Spring
, , ^ .
Hardware lor mounting control device

t Not inustrated.

A liis control device has a single arc chuta.
* This control device has double are chutes.

*Quantity is (1) for cotrtrol device with a single arc chute.
Ousntitv is (2) for control device with double arc chutes.

" SSya sjc^ complete information from nameplate of control device »h«m ordering replacement parts.

MftY. 5.199B

10:04fiM

PDS/ERflM MERRILLVILLE IN

NO.226

P.2/10

TYPE AM-7.2 MAGNE-BUST CIRCUIT BREAKERS

CSF-4435A

PARTS RECOMMENDED TOR NORMAL iSTOCK
ng.

Ref,

No,

No.

14
73
79
73
74
74
74
76
78

Z
2

2
2
2
2
2
2
2
2
2
2
3
a
9
3
3
S
4
4

84
84
84
84

142
156
167
174
17B
178
211
211

812
212
212
212
213
219

261
261
261
261
261
261
261
261
971
371
971
371

971

^11
411

663

CUalog Nnmber for Typo AM-7.2
AMPS

7S3<0363B02B8Fa02
02SlB070BGOai

AXX
ALL
ALL
ALL
25Q
SOO
ALL
ALL
ALL
ALL
ALL
ALL

Flexible connector Qelt, etort)
Flexllile connector (right)
Flexible conneetoi!< (right, long)

0313X03446032

8
3

Arcing contact aseem^

DiaiA5Bfl4P001

3
12
IB
24
18

ALL
ALL
250
500
250
SOO
ALL

ALL
260
ALL
250
500
ALL

250
250
250
250

SOON
SOON
500B

SOOH
500A

SODA
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

413
4"

663
663
738
738
763
763
759

ALL
1200
1200
2000
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
1200
1200

1200
2000
1200
20001200

1200

2000.
ALL

ALL

ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL

02B1B0708Q(I01
02a6C0791C001

qf^OBABqiTGOOS

029BC078QG008
0414AOUeF08B

012lASfi64Pa01
0414A0180PQai
006SOS787P001
0414A01B4P002

O414A011BpqO2
04S6A0S36P0OI

p421A0801Pa01

0414A01BTP001
0132Ca736F007

0431A0201FaOl

0132037370003
Oe02Bq742C0D9

0132Ca737G004
OlOaBSSSSGOOl

OB02B0742G004

QlOBBSSpeOODl

O137A91S4pa03
0114CS3a8P004
OMTASlBtfODS
0137A9164P004
0137AS164P004

0235007920031
0298007620015
0236007020015

0P6S7SS21G004
0B03B0799GflQl
0063755210003
OBOaB079BG003
00B97SS22O00S

0083755220002
008S7S522G005

Req'd

0114C63B2P004
0114C63B2P004
0114C53MP004
0819X0343GPD4
0213X0343C094
0212XB34SGO04
0069755216004

DeacrtpUon
BoostOr cylinder
Operating rod asaambly
FleidUe connector (left)

Plexlblo connector Oeft, long)

Flexible connector (right, short)

Primary contact finger spring
Primary contact finger apring >

Primary contact finger spring
Primary contact finger spring

Upper shield (MyealetO

bisolatlen plate
Lower minner barrier

6
6
3
3

Lower runner shield

Shield and cooler adsembly, right

Shield andcooler assemli^, left

-.9

Bdovatale ardng enntaat

3
a
6
6

Movable atdng contact

6
3

Movable primary contact
Mdvable primary contact
Movable primary contact
Movable prlm'ary contact
Movable primary contact
Mbvable primary contact

Tiibe and piston aasembly
Tuba and piston assembly
Tqbe and piston assembly
CIoBlngcoU (llOvd-c)

0602607990001

Closing ooB (126v d-c or 230v a-c, 80 he)

0063765210009
0802607900003

Closing coB (220v d'-c)

0068765220005

Closing coU (SSOv d-e)
CloslBg cqU (llOv d-c)

Closing eoU (125v

and 290va-e, 60hz)

0053755220001
0063795220004
0053755220003

0063755220002
0D8975S22G005
0063755220001
OD6S75S22G0O4
0063765220003

0DB174982G001

0061745620001

0061745020002

Potential farip coll (laSv d-c)

0061745020002
0061749820032
0062760700001

Potential trip coil (250v d-e]

00B174SB2G0S2
OQ627S07OG00L
OOB2750TQGOD2

0062750700002
006275017G016
0062760170033

Clselng coll (320v di-c)
Closing coll (260v d-c)

Closing coll (185v d-c or 230v a-c)
Closing coil (260v d-e)

Potential trip coll (230v a-e. he)

Potential trip coU (24v d-c)
Potential tHp coll (48v d-e)
UndervDltage device call (12Sv d-c)

UndexvoUige davlee coil (230r a-c, hz)

0061746890002
0061745990006

00627S017G020
POS174SB9G002

CndezvDltage davlcs coll (2S0v d-c)

0061745990006

ALL
ALL

00627S017G01B .
O0S27SQ17GO20

006275017G019
006275017G02Q

Capacitor trip coil (890v a-e, 60he)
Control device coU (12Sv d-e)

ALL

0C6275017Q033

Control device coll (250v d-c)

Current trip coil (9 apip, 60he)

(230v a-B, BOhe eontinuans)
(230va-e. BOhe intermittent)

d'Hefer to n^RiepUte or sunnnary for proper voltage ratlPB,

PDS/ERflM MERRILLVILLE IN

PDS/ERftM MERRILLVILLE IN

NO.226

P.1/10

>s-

GENERAL ELECTRIC COMPANY

SWITCHGEAR business DEPARTMENT

Philadelphia, pa I9i4a

RECOMMENDED PARTS
FOR

GEI-88763F •

Supersedes

MAINTENANCE

MAGNE-BLAST CIRCUIT BREAKER

TYPES:

AM-7.2-500-5
AM-7.2-500-6

1200 Si 2000 Amperes
With ML-13 Stored

Energy Mechanism

& •
fe ia '

Contents:
INTRODUCTION

. . 3

RICtlVINC. HANOLINC AND STOIAGi .

. ,

#3 yM
m

INSTALLATION

OISCRIRTION OT OPIIATION
ADJUSTMINTS

OINitAL MAINTiNANC
•INiWAL

RARTS.

general® ELECTRIC

magne-blast circuit breaker
AM-7.2-S00-5 (A)

AM-7.2-500-6 (A)

WITH TYPE ML-13 STORED ENERGY MECHANISM

Letter Designation B, C, H, K, N, and R, used immediately following
the model number indicates basic design features.
INTRODUCTION

The magne-blast breaker is the removable

and interchangeable interrupting element used in

^
Kr

its voltage, current, and interrupting ratings are
never exceeded.

Since this book is written to

metal-clad s^tchgear to provide reliable control
and protection of electrical apparatus and power

include all ratings of the breaker as well as several
design variations, the instructions will be of a

systems.

general character and all illustrations wiU be

The AM-7.2-500 Magne-blast Breaker is available with continuous current ratings of 1200

typical unless otherwise specified.

ang)eres and 2000 amperes in accordance with
applicable industry standards. Refer to the breaker

PROPER INSTALLATION AND MAINTE
NANCE ARE NECESSARY TO INSURE CONTINUED
SATISFACTORY OPERATION OF THE BREAKER.

nameplate for complete rating information of any

particular breaker. The nameplate also describes
the control power requirements for that breaker.
The supplication of a breaker must be such that

The following instructions will provide congilete
information for placing magne-blast breakers in
service and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
Receiving and HanHiinpr

against condensation, preferably by stor
ing it in a warm dry room, since water

Each breaker is carefullyinspectedandpacked
for shipment. Immediately upon receipt of the

absorption has an adverse effect on die
insulation parts. Circuit breakers for
out-door metal-clad switchgear should be
stored in the equipment only when power

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 com

is available and the heaters are in opera
tion to prevent condensation.

pany and the nearest General Electric Sales Office
should be notified.

The breaker should be stored in a clean

location, free from corrosive gases or

It is e]q)ected that due care will be exercised
during the uig)acking and installation of the breaker
so that no damage will occur from careless or

fumes; particular care should be taken to
protect the equipment from moisture and
cement dust, as this combination has a
very corosive effect on many parts.

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

be coated with grease to prevent rusting.

It is recommended that the breaker be put

•k
^

into service immediately in its permanent location,
If this is not possible, the following precautions
must be taken to insure the proper storage of the
breaker.

Unfinished surfaces of rollers, latches
etc., of the operating mechanism should

If the breaker is stored for any length of time,

should be inspected periodically to see diat
resting has not started and to insure good mechan

ical condition. Should the breaker be stored under

The breaker should be carefully protected

unfavorable atmospheric conditions, it should be
cleaned and dried out before beingplaced in service.

Cover Photo (8034807)

These instructions do not purport to cover ell deteils or variations in eqaipaent nor to provide for

every possible contingency to be met in connection with instaiJetion, operation or maintenance.

Should

rather information he desired or should particular problem arise which are not covered sufficiently for
the purchaser's purposes, the natter should be referred to the General Electric Conpany.
To the extent reguired the products described herein meet applicable AKSZ, IEEE and NEHA standards:

but no such assurance is given with respect to local codes and ordinances because they vary greatly.

•V a

' ..A

GEI-86763 Magne-Blast Circuit Breaker
INSTALLATION

* Kr
and Inspected
before shipment from the factory; however
before
facing the break®r in service the following items

BEEN TRIPPED OPEN OR MECHANICALLY
BLOCKED. THIS PRECAUTION IS REQUIRED TO
PREVENT ACCIDENTAL CLOSING OR TRIPPING

r%ould be checked to assure that no change has o™^urred during shipment and storage.

The closing springs should now be unblocked Ro
tate the driving eccentric until the indicator reads

1. Remove the box barriers and mechanism cover
and Mke a visial inspection to ascertain that the
breaker wdmechanism isin satisfactory condition
Check all bearing surfaces of the mechanism for

CHARGED" and the ratchet wheel does not advance.
The spring blocking device can now be removed.

n and^Rg^^^^^^^^

have remained tight, they should be checked during

3. To assure that the electrical connections

LUBRICATIONpage

installation as well as during each maintenance in

spection. This check of electrical connections is
particularly necessary on breakers used in nuclear

2. Charge the breaker closing sprinas mannoiiir

using a 5/^' ratchet wrench to turn the driving ec-

generating stations and other criticalapplications.

centric (4)n^rel. Turning the eccentric counteJ-

The bolted braid connections on the stationaryarcing

clockirae will advance the ratchet wheel and com

contacts should bechecked for tightness by removing
the arc chutes as described on page 15.

press the springs.

When the springs have reached the fully chara^d

4. Connect the test coigiler to the circuit breaker
Md operate it electrically seveKl times. Check

position the indicator (1) will read "CHARGED" Sd
the giving pawl will be raised from the ratchet
wheel teeth. Additional turningof the eccentric will

the control voltage as described under "CONTROL
POWER CHECK" (Page 14).

not advance the ratchet wheel.

5. Disconnect the test coupler and before replacing
the box barrier the primary bushings and other

iMert the ^ring blocking device (6) and manually

discharge the springs against the pins by pushing
the m^ual release button (3). The springs !ve now

^ckedandslowclosingof the breaker contacts can
i-»c with a 5/8 ratchet wrench.

driving eccen-

insulation should be wiped clean.

6. If the breaker has been stored for a long period
u .™®i' irtth
i astandard
recommended
insulationtest.
be
checked
60 hertzthat
highthepotential

Refer to Insulation Test (Page 17).

During the slow closing operation check to insure
that the mechanism does not stick or bind during
the enUre stroke, that it latches securely in the
closed iwsition, and that it trips freely when the
m^ant^ trip lever is operated. At this time also

bottthe motor leads from the terminal connection.

check the following-adjustments:

may cause damage to the winding insulation.

a. Arcing contact wipe (Refer to page 111
b. Primary contact wipe (Refer to page 11)

c. Primary contact gap (Refer to pa^ n)

DO NOT WORK ON EITHER THE BREAKER OR
MECHANISM UNLESS THE CLOSING SPRINGS ARE
BLOCKED
AND THE OPENING SPRmS HAVE

NOTE: If the breaker secondary wiring is to

be given a hi-potential test at 1500 volts, remove
Failure to disconnect the motor from the circuit

t^® sWv®r portion of the ball contact

° "^® ' *'®®^®'^ bushing and the rear porK
contact Ilubricant
D50H47. by applying a thin film of
8. Refer to metal-clad instruction book GEH-1802

Pescriptign of operation

The Magne-blast Breaker has two princmni

°P®'^ting
ML-13
of the
stored'^^®energy
tj^emechanism
designed ^typegi^
Ughis^d
closing and opening. The mechanism will onerate

on a-c or d-c voltage as indic^Si the bSr

parts, m^wd arcing contacts, interrupter^nd
Pe "^®*^system
insulation
b^#d»e^en poles,
or phases that
and-provides
to ground.
The

connections to the associated n^tk-clad

switchgear are made through the baU Sntecte
at
the top of the breaker bushings.
t-oniacts at

• Indicates revision

nameplate.

Closing and opening operations are

metal-clad
remote location, or mechanically
by the
manuU close and trip levers on the breaker All

secondary connections from the breaker to ^

(img5« 2."°"

the cSpfer

M
"

Magne-Blast Circuit Breaker GEI-88763

A spriT^ release interlock, Figure 3 is

provided to discharge both the cloknglnd opemS

springs when the breaker is withdrawn from or
inserted into the metal-clad unit.

Figure 1. (8040935) Spring Blocking Device
Charge-Dischai^e Device

Driving Pawl
Manual Close Button
Eccentric

Manual Charging Wrench

spring Blocking Device

Figure 2. (8040932) Left Side View ML-13
Operating Mechanism

Closing Roller
Power Switches
Closmg Latch

Figure 3. (8038805) Spring Discharge Linkage

10.
1.

Link

2.
3.
4.
5.
6.

Adjusting Bolt
Trip Latch Crank
Discharge Crank
Adjusting Clevis
Spring Release Crank

Interlock Switches

Latch Checking Switch

Closing Springs
Motor

I ?:
discharged against the positive tateJhS tJ
mechamsm wUl be jammed and be

The mechanism can be released and rebirn^H fn

the reset position by pushing in on
lever (8) . Figure 5, It mav rprnH.2

normal force to release the interlock"

When the breaker is used interchaneeablv

MS-13 solenoid operated breaklrs

M-36 metal-clad units, fuses are mounted on the

^TV,

of the motor and closing

fa "C"
^1®"tifled
by eithef
u or
or "ic"
K suffix in the breaker
nomenclature.
In cases where breakers with type ML-13
mechamsms must match and line up with bre^^ers

having type ML-11 mech^isms the spring chareiS
both mechanisms should be fused with
Buss Company Fusetrons as follows:

''L::g=l

Figure 4. (8038804) Right Side View ML-U
Operating Mechanism
Upper Spring Pin —
0C>U>7^.^PffS
Latching Pawls
Positive Interlock Roller
Opening Spring
Cam Shaft

Ratchet Wheel
Bearing Block
Driving Pawl

Lower Spring Pin
Driving Pawl Lever
Eccentric

Closing Spring

Figure 5. (8040934) Fiont View ML-13 Operating
Mechanism

Prop Springs
Operation Counter

Trip Latch

n*
8.
9.

£^^^®!"P^®^barge
Manual Trip Lever Indicator
Manual Close Button

10.

Motor

Magne-Blast Circuit Breaker GEI-8e763
Cont. Volt

Fuse Size

48v d-c
llOv d-c
125v d-c

lOA
4A
4A
4A

llSv a-c

220v d-c
250v d-c
230v a-c

2.5A
2.5A
2.5A

Cat. No.

^ straight
through
the
eccentric (11) Figure
4, and astroke
lever that
carries
a spring loaded driving pawl (2), Figure 1.

FRN 10
FRN 4

"^e pawl advances the ratchetwheel (6) Figure
4 a few degrees each stroke where it is held in
pawls (2). When the ratchet
wheel h^ been rotated approximately 180 degrees
the cl^osing springs (12) will be fully compressed
As the ratchet wheel continues to rotate, the

FRN 4

FRN
FRN
FRN
FRN

4
2.5
2.5
2.5

spn^ load will shift over center and attemot
to discharge. After a few degrees of rotation the
(10)
^
motor
uuy pig^ire 3, that compresses
a set sear
nf rinQino-

springs through the action of an eccentk? rSf

and pawl assembly. The rota?? Lt?on 3^he mo?o?'

springs will be
held by the latch compressed
until a closing
operation is
Wheel
vSl^rotnr^^^fh
rotation the power switches
degrees(7)of are
the ratchet
opened
•vUiUK

Figure 6. (8040933) Control Mechanism

SwSc''h?am'''"'

Switch Striker

Switch Support Bolts
Switch Support
Closing Latch Roller

Power Switches

Closing Latch

posing Latch Shaft

Latch Adjusting Screw
Closing Coil Bolts

Closing Latch Spring

Latch Monitoring Switch
Switch Mounting Bracket
Closing Solenoid
Closing Coil Support
Control Relay

Q£I«88763 Magne«Blafit Circuit Breeucer

and the driving pawl Is raised from the ratchet

wheel surface, this ^ows the motor wd dri^lna

power is suddenly restored without warning. In

this event, the motor drive will overri& the

ratchet wrench and continues to charge the springs.

Closing Operation

nold the closing circuit open. The relay femaina

The breaker can be closed electrlcallv bv
energizing the closing solenoid (15) Figure 6 or
manually by pushing the close button (9) Figure 5

The clostag springs may be charged manuaUv
If control voltage Is lost. A 5/8" ratchet

under the closing roller to release toe ciosSS

energized until the springs are fully chweed^d
the control switch contecte are re^el ®

T
in aSS
clockwise direction until eccktrlc
the Indlcator^adl

Charged '• and the drlvli^ pawl is raised fmnf
wtchet wheel. The use of the ratchet wrench pro

vides for maximum safety in the event that coK

In either method tbTe closing latch Is rotaWrom

OTrings (9) Figure 2. The energy in toe springs
is used to rotate a cam (8) Figure 7 and close toe

brewer throiwh the operating mechanism linkage.
During the closing operation toe mechani^is

trip-free at all times. The breaker Is held closed

toe prop pin (4).

position under
During toe closing
operation

Figure 7(0134C3583) Sectional Side View of Mechanism
1.
2.
3.
4.
5.
6.

Main Shaft Bearing
Crank Shaft
Cranks

Prop Pin
Prop
Cam Shaft

Cam Shaft Bearing
Cam

Handle

10.
11.
12.
13.
14.
15.

16.
17.
18.

Trip Coil
Upper Prop Spring
J rip Armature
Lower Prop Spring

Lam Follower Roller

Trip Shaft
Trip Latch

Stop Pin

20. Trip Latch Roller
21. cKSS"
22. Stop
Plate
23! Spring
Rod

24.
Spring
25 Spring
26* Spring Guide

(

Magne-Blast Circjiit Breaker GEI-88763

Jin

trip llt^h

4, are compressed

f?JmS ?Ph"^ operation with the

ul?h roUer (19K^

«"P

comets

"P®"';®? °t ttie breaker Is

«?«
*
closing
latch isswitch
fully closes
reset
the 5i
contecte
of S^®
the latch
monitoring

released to provide the required opening speed

for successful internq)tion of the circuit.

xu
to interrupt
a current,
me arc ^®
firstbreaker
starts atopens
the arcing
contacts
(5 &2li

Figure 8, transfers to the arc runner (3 &8) and
ener^zes the blow-out coils (2 &7). This action

to pern^t the spring charging motor to be enerrized

tatro^ces a mapetic field between the pole pieces
(4 &9) of the inter™ter thatforces the arc deeper

Opening Operation

mcts part a dischaiige of air is eiroelled through
tte booster tube (22) across the arc. This air

and recharge the closing springs.

®oergized

The breaker can be opened either eJectricallv

bv Suishii?^*^f
coil (3) Figure
5, or manually
^® operating
P lever off
the trip latch
rollerto
mechanism
linkage
collapse. The energy stored in the opening^ings

hito the arc chute (6). At the time the arcing con-

flow assists the arc transfer and internmtion by
mowing the arc away from the contacts and into
me ^c chute. As the magnetic field forces the

arc deeper into the interrupter along the diverging
^c runners, the field is progressively increased
by the iMertion of each additional blow-out coil
mto the circuit.

)

Figure 8(0152C5904) Cross Section of Breaker Pole
Box Barrier

Upper Blow-Out Coil

Upper Arc Runner
Upper Pole Pieces

Stationary Arcing Contact
Arc Chute Side

Lower Blow-Out Coil
Lower Arc Runner

Unit
9.
10.
11.
12.
13.
14.
15.
16.

Lower Pole Pieces
Front Bushing

17
13*
Rear Bushing
jg]
Upper Horizontal Barrier 20*
Main Operating Crank
21*
Spring Retainer
22'
Lower Horizontal Barrier 23*
Operating Rod
24*

Stationary Primary Contact
Movable Primary Contact
Hinge Cup Bearing

Contact Arm Assembly

Movable Arcing Contact

Booster Tube and Piston
Connectlin Bar

Booster Cylinder

iiii;i-887S3 Magne-Blaat Circuit Breaker

ceraL^S.-;
toe
interrupter it is lengthened in the

Trip Free Operation

the electrical resistance of toe mc £

breaker is closing, the trip armature will force
toe trip latch (17) Figure 7 away from the trip
roller (19) causing toe mechanism linkaae to
collapse and the breaker to re-open. The (^sin?
cam (8) will complete its closing stroke and the

deepeiUng serpentine path between the finJ s^thS
^^crewed Md its heat is absorbed by toe ce??JSc
.aterial. The increased resistance reAr/fJif^ka
magnitude and-phase angle of the current
M early current zero the arc caJnot reSLSSich
itself and interruption occurs,
®stabllsh

If toe trip coil circuit is energized while the

lllriLT

^ a^ornT^Sostal

Primary Contact Wipe

, .
Arcing Contact Wipe

Figure 9A, "-5" Contact Structure (0114C5320)

Primary Contact Wipe

Arcing Contact Wipe

Figure 9B. "-6" Contact Structure (0132C2778)
Figure 9 Contacts Adjustments
9*

^*'^™ary Contacts

I; S
4. Stationary Arcing Contacts
10

5.
6.
7.

Arcing Contacts

Contact Arm
Throat Baffle

Magne-Blast Circuit Breaker GEI-88763
ADJUSTMENTS

^^i"^strnents should be checked during

®-S^lcSsarv
^lecessary

to repair or replace
whenever
partsit that
becomes
have

oecome worn or defective while iS «rvS ThI
following adjustments are Usted in the order ^
which they are to be checked aiter remov'n^ thS
box barriers and front cover from the breaker.
DO NOT WORK ON EITHER THE rrfaktt?

are" BL'S'c'Jgn
_

HAVE BEEN^mo^/S^ OPENING SPRINGS
BLOClSrn
MECHANICALLY
PREVF^*Arrmrvri?A^T^^^
^ REQUIRED
TO
PREVENT ACCIDENTAL CLOSING
ORTRIPPING.

Arcing Contact Wipe

ta^feTSfch
ihfi

At?

a?"indicator
^="•=""
or bell'oXuii
set. In

setting h^ been made in the factory mid no adf

gustment is provided. A wipe of less ulli 5/f6"

repSc^d l^en"^m
" ®aking

this

contactsseeneed
be
check,
thatto the

Figure 10. (8038802). Adjustable Coupling For
Making Primary Contact
Wipe Adjustments

1.
2.
3.

Operating Rod
Operating Rod Pin
Adjusting Nut

Check Nut

5. Stationary Primary Contacts

Movable Primary Contacts

breaker is closed

contacts (1) should rise

breiS?"aiS® ?efer^^"^ct'adjustment.^penTe

ehSSKL
checking th^
the

ON THE MECHANISM INTHE

sPrimarvEsHSSContact r.ap

fi7i
S/Il®"
erea^o nn

Figure 7. The wipe of the trip latch

(19) should be from 3/16" to

measured
puttingpart
a fUm
of
closing theby
breaker
way.
mechanism has the proper trip

FnLin?,-; ^ adjustment is provided and a visui

b5«?H«F=FS5:
J -l-aen the chack nSt (21) F'iJre

S.1?ini

IS usually all that is required. If this

of ^tr^, sSljfal)°"'

ihBoffiofent travel

Trip Armature Travel

have^^/16"
have 1/16 to 3/16" travel plus
armature
1/32"(13)
minimum
should
" Indicates revision

GEI-88783 Magne-Blast Circuit Breaker
2Y®rtravel
thebytrip
latch the
(17)trio
starts
' This
can bebefore
adjusted
moving
coilto

(^t 180 degrees rotation of cam). At this point

the clearance between the striker and the switch

Figure 11. A locking screw located behinH fiT * •

^mature screw must first be iSsened

,>*sklng screw after ma^g adjustment. "
Closing Latch Wipe

Interlock Switch Wipe

Refer to Figure 8.

f
1/4

. If re-setting

support (5) should be 1/32" or lessT Twl S he
bSifff?!
bolts
(4) and rotating the support. support mounting

The wine betwoet,

(®) sho?ad
be 3/l6"^o
isroll®!required,
loosen
set

retighten adjustment nut and screw (10),'

tn
WitJ^ti^®POsiUveinterIock
hlnHi
position
be^een the interlock switch
armthe(2)clearance
and the
plate by
(3) bending
should bethe1/W"
or arm.
lesTs!
This can be adjusted
switch

Closing Latch Monitoring Switch
Driving Pawl Adjustment

Refer to Figure 6. The closing latch mnef
f®:®®t and the latch monitortng switch flst
operated before the motor wiU start Whil ♦k '

latch is fuUy reset theclearancebe^^ntoel^t^h

uieVtriir arml'"''

pawl (8)
must advance the ratchet Th®
wheeldriving
(6) sufficientlv

on each stroke to allow the latchiigTawIs (2^

mounting bSet

benSi^

Motor and Relay Switches

charged. Slowly®?ot5I

wreS iS

the drivu^ pawl has traveled thrmTgh iS remS

striker (3) has traveled the maximum aSmS

fhl
the maximum
clearance
between
the pawland
andcheck
the ratchet
tooth. Rotate
the charrtner

wrench until the driving pawl has advanced^

Figure a. (8040934) Auxillery Switch and Trip Coll
1.

Trip Latch Spring

Switch Arm

3.
3.
Spring Discharge Crank

Cotter Pin

5.
5.

Trip Coil Support
Trip Coil
Mounting Bolts
Latch Set Screws
Trip Latch

8.
7.
J.
•i.

11.
I.

Trip Arm Screw

Manual Trip Lever
• Indicates revision

Figure 12. (8040933) Positive Interlock Switch
1.

Positive Interlock Shaft

Switch Arm

Switch Support

Interlock Switch

5. Latch Checking Switch

6.
7.

Switch Arm
Trip Shaft

Magne-Blast Circuit Breaker GEI-88763

ratchet tooth to its maximum travel. Now check
and. the
latch^ pawl. The clearance shouldtooth
be approxi-

mately equal for both the driving and latchiS pawls

,^and not less than .015" in either case.

If adjustment is required for either pawl the
T
besupport
fully charged
andFigure
blocked.
Loosen
seven ^trst
motor
bolts (1)
15
jmd move entire motor assembly to the rear if
the minimum at the latching

pawls, ^d to tte front if the clearance is under

the m^mum at the driving pawl. Move the motor
assembly approximately twice the dimensional
mcrease required at the pawl. Be certain the
motor ^sembly is moved straight forward or
and tighten
the one
the right
side
of the ^ mounting
frame
firstbolt
toonassure
proper

^^®i j ^^^tening
remaining
bolts
^e spr^s should
be releasedtheand
the clearance

again checked as described above.

AUXILIARY DEVICES
Latch Checking Switch

Chargethe linkage.
closing springs
^ficiently to^^''®
reset the mechanism
Rotate
1
pressingswitch
the manual
to open Ih
toe latch
checking
(2). trip
Allowlever
toe
^®®?* slowly
point
at whichu the contacts
are and
madedetermine
by using atoecircuit
continuity tester (light indicator, beU set, etc),
^he contacts of the latch checking switch should
ust make when toe gap between toe trip latch

Hnwv\^® 1

1? located on the latch roller

Z • toe switch
should
be (3)
a minimum
of 1ill.'
1/64 I,be^een
arm
and toe
switch ^pport (1). To obtain adjustment of toe

Figure 13. (0114C5320) Latch Checking Switch
1.
2.

Switch Support
Latch Checking Switch

Latch Roller Link
Latch Roller Pin

Plunger Interlock

Refer to Figure 14. With the breaker in toe
closed position, the vertical distance "A" from

wSr im® Pl'^fr^^lt (1) to toe bottom of toe
Vi
^
should be 11-7/32" to
il' y washers
•u
/S?^®
remove
(2).

'-88763 Magne-Blast Circuit Breaker
»

METHOD OF CLEANING
BEARINGS

Whenever cleaning of bearings is required, as
^i»d,icated in the lubrication chart, the following pro.ures are recommended.

Sleeve Bearings

The sleeve bearings used in the prop (5) Fig
ure 7 and the bearings for the trip shaft (16) utilize
Teflon surfaces and do not require lubrication.
After a number of operations, the surface will ac
quire a thin black film. Do not remove this film

unless there is evidence of outside contaminants,
such as dry or hardened grease. If contaminants

are present they should be removed by immersing
theprop andbearing in clean petroleum solvent, or
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
frame should be cleaned and relubricated with G-E
D50H15 lubricant at general overhaul periods. This

includesthe bearings in the driving link (8) Figure
15, driving pawl lever (10) Figure 4, driving pawl

(8), latching pawls (2), trip latch roller support

(20) Figure 7, cranks (3), and the bearings in the
mechanism frame and interconnecting links. Bear -

i^thatarepressed into the frame or other mechr

members should not be removed.

G-E lubricant D50H15 being sure all metal parts
are greased.

The inner races should then be

assembled.

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 antifreeze should be
used. Even then the bearings should be removed
from the alcohol within twenty-four hours. Pre
cautions 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 the bearings in

the light oil, draining and repacking with lubricant
D50H15 should follow immediately.
Bearings that are pressed into the frame or

other members such as the motor support (9)
Figure 15, should not be removed. After removing
the shaft and inner race the bearing can be cleaned
satisfactorily 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
race and shaft.

Rolling Surfaces

A number of rolling and rubbing surfaces in
the mechanism have been lubricated with a baked-

on dry, molybdenum disulfide coating.

This

lubrication, which can be recognized by its d^k

The cup bearing (19)'Figure 8 of the primary
contact arm should be disassembled, cleaned,
and lubricated with G-E D50H47 lubricant at gen

almost black color (e.g. Face of switch cam (5)

eral overhaul periods.

Other rolling or rubbii^ surfaces that are not
lubricated with molybdenum disulfide should have
the dried, dirty grease removed and a thin film
of fresh lubricant D50H15 applied.

The main shaft bearings (1) Figure 7 should
be removed, cleaned, and lubricated with G-E

D50H15 lubricant a^eneral overhaul periods.
Roller and Needle Bearings
Refer to Figure 7. Bearings in the cam follower

(15), latch roller (19), and cam shaft bearings (7)

should be removed from the mechanism and the
inner race disassembled. They should then be
placed in a container of clean petroleum solvent
or similar cleaner.
DO 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
remove it. Ordinarily, by agitating the bearings

Figure 2) requires no maintenance and should

last the life of the breaker.

MAINTENANCE

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 of the applications.

The following schedule is recommended for such
breakers:

Every 500 Operations:
1.

Remove the box barriers.

Wipe all insulating parts clean of
smoke deposit and dust with a clean

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 bands as deposits from the
skin onto the bearings are inductive to corrosion
If the bearings are touched, the contamination can
be removed by washing in alcohol. After the
have been thoroughly cleaned, spin them in
c; 1 new light machine oil until the cleaner or
solvent is entirely removed. Allow this oil to

drain off and then repack them immediately with

* Indicates revision

dry cloth, including the bushings, and

the inside of the box barriers.
All flat parts in the throat area of the

interrupters should be thoroughly
cleaned by using sandpaper. This
cleaning should be performed any time
the interrupter is removed. The arc
chute sides and throat cooler fins
should not be cleaned. Whenever the

mterrupter is removed, loose dust and

dirt should be blown out before re-

Magne-BloBt Circuit Breaker OEI-86763
eary readjustments should be made as
described under ADJUSTMENTS.

it should be operated manually to
be sure there is no binding orfriction

B. Every 2000 Operations, or Every Six

and

Months, Whichever Comes First:

In addition to the servicing done each
500 operations, the following inspec

tion should then be checked using

tion shoiild be made and work done

couplers.

Primary Contacts (3 and 10 Figure
23).
Inspect the condition of the
stationary contact fingers and mova
ble contact blocks. Badly pitted or
tarned contacts should be replaced.

either the test cabinet or the test

C. After Every 10,000 Operations:
1.

they should be smoothed with crociis
cloth or draw filed. After contact

dressing the primary contacts should
be greased lightiy with D50H47.

and disassembled to permit a detailed
inspection of insulation, blow-out

coils, arc runners and assemblies
which can become contaminated by
arc products.
2.

from arc action and heat so that the

turns of the coils are not fully in
sulated from each other, the coils
should be replaced. All connections
should be checked for tightness.

than the minimum specined \mder
ADJUSTMENTS, the contacte should
be replaced. The contacts shotdd be

area h^ been reduced to 25% of the
original metal thickness as a result
of

need for

checked for possible cleaning or re

The breaker and operating mechanism
should be carefully inspected for loose
nuts, bolts, and loose or damaged set
screws or other locking devices. All
cam, latch and roller surfaces should

be inspected for damage or excessive
wear.

Insulating material that is carbonized
and cannot be satisfactorily cleaned
should be replaced.

Any parts damaged or severely burned
and/or eroded from arc action should

The buffer blocks and their

be replaced.

NOTE:

is to be expected with ceramic ma
terials 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. Small broken comers

The contacts of the control relay
(17) Figure .6, should be inspected

for wear and cleaned if necessary.

Lubricate the breaker operating mech

on the exhaust end of the arc chute

anism in.accordancewito instructions

will not interfere with its performance
and can also be disregarded.

under LUBRICATION, page 17 and
the lubrication chart Figure 17.

Inspect all wiring for tightness of
connections and possible damage of
insulation.

Fine cracks may develop in

the fins of the arc chute sides. This

placement.

Check the stationary arc contacts to
tions are tight.

tionary contact support should be
inspected for possible need of re

On arc runners

good condition and that their connec

retainers on the bottom of the sta

erosion.

assure that the arming contacts are in

placement. Do not grease the arcing
contacts under any circunistan<^flfl.

arc

with arc resistant surface coating,
replace runner when surface coating
has been penetrated.

replacement. If the interrupters are

removed, the contact braids, and other
parts subject to arcing should be

The arc runners should be inspected
and replaced when any part erf their

not be necessary to remove the inter
rupters for this 2000 operation ser
vicing unless inadequate wipe or con
tact condition indicate a

The blow-out coils should be care

fully examined and if the insulation
has been cracked, shrunk or eroded

Arcing Contacts (5 and 21 Figure 8).
When the arcing contact wipe is less

inspected for uneven wear and/or
damage using a mirror to inspect the
stationary contacts. Normally it will

In addition to the servicing done
each 2000 operations, the interrupters
should be removed from the breaker

(Note: Burned primary contacts in
dicate the probable need for arcing
contact replacement.) If the contact
surfaces are only roughened or galled,

that the breaker contacts can

move to the fully opened and fully
closed positions. Its electrical opera

when required.

After the breaker has been serviced,

The cup bearing and the contact ring
at the hinge point of the contact blade
should be (Usassembled, inspected,
cleaned, and relubricated with G-£
19

GEI-88763 -Magne-Blast Circuit Breaker

Figure 18A. (8036083) "-5" Design

Figure 18B (8040393) "«6" Design

Figure 18. Interrupter Assembly
Assembly Bolts
Assembly Bolt
Upper Pole Pieces
Rear Brace

Assembly Bolt
Side Brace

Assembly Bolts
Upper Supports
Assembly Bolt

.4.

Assembly Bolts

'3.

Upper Interrupter Support

contact lubricant D50H47. The con
tact ring should be inspected for
wear and replaced when reduced in
thickness to less than 1/32". When
reassembling the cup bearing, be sure
^e cotter pin is properly assembled
m the castle nut on the hinge pin {?)

Figure 23,

This assures proper

contact pressure at the hinge.
D. Every 20,0000perationsorApproximatelv

Every Five Years- Whichever comes first:
1. The breaker should begiven a general
inspection and overhaul as required
All excessively worn parts in^oththe
mechanism and breaker should be
replaced. Such wear will usually be
indicated when the breaker cannot be
adjusted to indicatedtolerances. This
overhaul and inspection is more de

15.
16.

Upper Insulation
Assembly Bolts

Assembly Bolts
Assembly Bolt

19. Lower Interrupter Support

tailed and will require disassemblyof
mechanism and breaker operating
parts.

2. All roller and needle bearings in the
operating mechanism should be dis

assembled, cleaned, and repacked
with G-E lubricant D50H15 as de
scribed under LUBRICATION.

3. The stationary primary contact fin

gers (3) Figure 23, should be disas
sembled and the silver-plated pivot
area of the contact and contact sup
port cleaned and lubricated with G-E

lubricant D50H47.

4. The breakerand operating mechanism
should be serviced as described for

every 2,000 operations and properly
adjusted before being put back into

service.

MasneoBlast Circuit Breaker GEI-88763

Figure 19A.(8021965) "-5" Design

Figure 19B. (8040391) "-6" Design

Figure 19, Interrupter Assembly with Side Removed
1. Upper Arc Runner Spacers
6. Arc Chute Side
11. Lower Arc Runner Spacers
2. Upper Arc Runner Assembly 7.
Upper Insulation
12.
Lower Arc Runner Assembly
3. Blowout Core
4.

Lower Arc Runner
Lower Insulation

REPAIR AND REPLACEMENT

section covers the proper method of

those parts of the breaker
Pn^TA^T UPON COMPLETION
the installation.
IMPOnTANT:
OF ANY RF
^AIR WORK, ALL BREAKER AND MECHANISM
ADJUSTMENTS
MUST BE CHECKED.
Refer to
the
section on INSTALLATION,
paying particular

subject to damage and wear that may require

TION

adjustments and FINAL INSPECCH^TE (To inspect or replace blow-out

coils and arc runners):

the breaker open and the closing springs
o position, remove the box barriers

♦ *1,
can now be
assembled to
the tbreaker and lifter
the interrupter

Lower Coil Connection

described under INTERRUPTER RE

MOVAL AND REPLACEMENT page 16 .

To ^sassemble the arc chute 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., will be found that cannot be identified in
these instructions. Care should be taken to collect
and identify these items so they can be reassembled
correctly.

1. Remove the assembly bolts (2, 5, 8, 10.
14, 16, and 18) Figure 18.
' ' ' »
®lde brace (6) and rear brace

(4), the upper pole pieces (3), and the
lower pole pieces (7).

GEI-88763 Magne-Blast Circuit Breaker

To remove the upper supports (11), and
upper interrupter support (13) removethe

assembly bolts (1 and 12), and the bolted
connection between the upper interrupter
support and the blowout coil.

Remove the assembly bolt (21) to remove
the lower brace (9).

Remove the lower interruptersupport(19)
by removingthe assembly bolts (20) Figure
18 and the connection nut (8) Figure 20.

6. At this point, the side shields (5) Figure
20, and the upper arc dinner assembly
(2) can be removed. On the "-6" design
the throat coolers (8) Figure 19b, are

permanently affixed to the side shields.

Further disassembly of both the upper and
lower arc runner assemblies can be done
by removing the various screws and
assembly bolts (not illustrated) as shown
in Figure 19.

The arc chute sides (6) Figure 19, canalso
be separated for inspection.

Reassemble the interrupter in the reverse
order. The following items should be noted during
reassembly:

4ure 20. (8040392) Interrupter Assembly
1.

Upper Support

Insulation

Upper Arc Runner Assembly

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 should

be parallel and in line.

The gap between the fins at the rear of

Upper Arc Runner

Side Shield

the arc chute sides measured at least
1" in from the back end of the arc chute

7.
8.

Lower CoU Connection
Connection Nut

on the "-5" design and 0 to 1/16" on the
"-6" design interrupter.

(See Figure 21) should be 3/64" to 3/32"

Lower Arc Runner Assembly
3.

Check to insure that electrical connections
to the blowout coils are tight.

When reassembling the arc runner as

semblies, check that the spacers (1 and
11) Figure 19, are correctly installed.

5. Before bolting the uppersupportsinplace,
make certain that the upper arc runner
assembly is tight against the arc chute

side so that the gap between the upper
insulation (7) Figure 19, and the arc
chute sides (6) is a minimum.

On the

-6" design the throat coolers (8) should
also be assembled tightly against the arc
chute sides.

Make certain that the electrical connec
tions are tight.

Figure 21. (8029373) Arc Chute Fin Spacing

Reassemble the Interrupter on the breaker
as described under ARC CHUTE REMOVAL AND
REPLACEMENT, page 16 .

Magne-Blast Circuit Breaker GEI-88763

I: t
II
/, 52C IIZI <15 ^o.
.1

Figure 22A. (8025170) "-5" Design

Figure 22B. ,(8039457) "-6" Design

Figure 22. Rear Bushing Assembly

i*
5®??" Bushing
MountingBraid
Bolt
2. Guide
and Support for Interrupter 7.6. Flexible

11
Sorina Baffle
12 Sftinfpiate

5* Bort^SrTlSbL
RrfliH
Boit :or riexibie Braid

14. Throat Barrier

3. Bolts for Contact Support

8. Connection Bolt

13 S i ®

Stud for Mounting
Arcing Assembly
Fingers
10. Stationary
Arcing Contact

CONTACTS

On the "-6" design, grasp the lower
end of the contact fingers with pliers
and move the contact assembly to

Open the breaker and remove the box barriers
and interrupters as previously described. To

wards rear of stud to remove from

remove the contacts, proceed as follows:

A. Stationary ArcingContacts (10) Figure22.
1.

Disconnect the contactbraids (7) from
the contact fingers by removing two
bolts and locking plates (8),

On the "-5" design, grasp the lower
end of the contact fingers with pliers
and pull contact assembly downward
to remove from stud assembly.

plate remove one bolt (5).

To disassemble stud plate from con
tact support, remove two bolts (6).

Reassemble in the reverse order,
make sure locking plates are properly
reassembled with bolts (8).

GEI-80763 Magne-Blast Circuit Dvei'.ker

Movable Arcing Contact (14) Figure 23.

Remove the assembly bolts (12) mak
ing note of quantity and location of
shims and spacers used between con
tacts and contact arms.

Reassemble in reverse order, re
using the shims and spacers.

Close the breaker slowly to check
that the movable arcing contact is
approximately centered on the sta
tionary arcing contact and that it
does not rub on either side of the
throat barrier (9).
NOTE:

• r ?

Whenever it is found neces

sary to replace arcing contacts on any
pole of a breaker it is recommended
that both the stationary and movable
contacts on that pole be replaced at
the same time.

C. Stationary Primary Contacts (9) Figure 24.

1. Compress the contact spring (6) by
use of the spring compressor.

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

Figure 23.

(8038805) Contact Assembly

a time.

To replace the Stationary Primary Contacts:

Apply a thin coating ofD50H47 grease
on the hinged edge of the finger (9)

then place it on the contact support
(7) so tliat it is retained by stoo

plate (8).

Open spring compressor (3) and as
semble spring guide, spring and
spring compressor (Figure 24A).
Turn nut (2) in clockwise direction

to compress contact spring (Figure
24B). Hold spring firmly in yoke

Front Bushing
Contact Springs
Stationary Primary Contacts
Operating Rod Pin
Buffer

Cup Bearing
Hinge Pin
Contact Arm
Throat Barrier

Movable Primary Contacts
Assembly BoltsT

Assembly BoltsJ MoTPiston Assembly
Movable Arcing Contact
Connection Bar

on spring compressor to prevent
spring from slipping out of the com
pressor.

Place washer (not shown) on guide on
t^op of spring, place top of guide into

hole in spring retainer (4) and the
round end of spring guide in cutout
m primary finger (Figure 24C).

bolts (11) and remove the movable

primary contacts (10).

5. Hold spring assembly firmly in place

Movable PrimaryContacts(10) Figure23.

tacts on a 2000 ampere breaker it is first

and remove spring compressor.

tacts on a 1200 ampere breaker proceed

To replace the movable primary con-

Reassemble in reverse order.

To replace the movable primary con
A

& I- ^

Magne-Blaflt Circuit Breaker GEI-887e3

Figure 24. Method of Installing Primary Contact Springs
Using A Spring Compressor.
Spring Guide
Compressor Nut
Spring Compressor
Spring Retainer
Assembly Bolts
H

Stationary Primary
Finger

GEI-88763 Magne-Blast Circuit Breaker

Disassemble operating rod pin (4)
first noting quantity and location of

washers in the assembly.
2.

Pry contact arms (8) apart enough

to disengage pivot pins of piston
assembly (13) allowing piston to drop

To replace the bushing, proceed as follows:
Rear Bushing
1.

Rotate the two parts of the contact
arm assembly away from each other
so assembly bolts (11) are accessible

and movable primary contacts ho)

scribed.

Reassemble in reverse order.

Remove connection bar (15).

Disassemble hingepin (7), cupbearing

(6), and operating rod pin (4) noting

NOTE:

moimting flange on some, or all bolts.

bushing and may be required when new
bushings are assembled.

be removed.

When reassembling,
first insert
piston tube assembly (13) into the
booster cylinder and reassemble the
cup bearing, making sure the silvered

Disassemble the spring retainer (4) by
removing mounting bolts (5).

Referring to Fimre 22, disassemble the
contact support (4) and interrupter mount
ing bracket (2) removing two bolts (3).
Reassemble in the reverse order.

The

interrupter mounting bracket (2) is not

contact washers between the bushing
and contact arms (both sides) are
5.

Referring to Figure 24, disassemble the
primary contact springs (6) as previously
described.

and spacers used in assemblies.

The contact arm assembly includine
the piston assembly (13) can now

Shims may be foimd between the

These shims are for squaring up the

quantity and location of any washers

Remove the four t)olts at the mounting

breaker mounting plate and the bushing

Contact Arm Assembly (8, 10 13 14)
Figure 23.
'
'
1.

Remove the upper and lower horizontal
barriers (12 and 15) Figure 8.

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

can be removed.

symmetrical and must be assembled cor

in place.

rectly to orient the interrupter properly
on the breaker. The longest projection

Reassemble operating rod pin (4) and

of the bracket should be toward the lower
end of the bushing.

connection bar (15).

F. After disassembly and reassembly of any
contactsv check all contact adjustments

Front Bushing

as described under ADJUSTMENTS.

Open the breaker and remove the box
barriers and interrupters as already de
scribed.

BUSHINGS

IMPORTANT: DO NOT REMOVE ALL SIX
BUSHINGS AT ONCE. The bushings have bera
carefully aligned with the breaker frame, during
assembly at the factory, and it is important tiiai
this alignment be maintained to insure interch^eability of the breakers in the metal-clad
units. 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 ad

jacent bushings in both directions, so that it mav

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 the bushings may be
^^coraplished by placing the breaker in a de' lergized spare metal-clad unit before tightening
aie bushing mounting bolts. This must be done
before the interrupters are reinstalled.

barriers and interrupters as already de

down into its booster cylinder.
3.

Open the breaker and remove the box

Remove the upper and lower horizontal
barriers (12 and 15) Figure 8.

3' Remove the connection bar (15) Figure

23, cup bearing (6), and hinge pin (7).
4. Remove the four bolts at the mounting
flange of the front bushing being removed,
and lower^ the bushing. (See note under
rear bushings concerning use of shims).

When reassembling, first mount the bush
ing and assemble the cup bearing (6),

contact arm (8), and replace pin (7) being

sure the silvered contact washers between

me bushing and contact arms are in place.
surfaces
at the
hingeshould
point
of* the contact
blade and
bushing

have a thin coating of D50H47 grease.
6. Check ^ contact adjustments as outlined
under ADJUSTMENTS.

(

Magne-Blast Circuit Breaker GEI-88763
INTERLOCK SWITCH

7. Shaft, latch, etc., may now be removed
by driving it to the left. Note quantity
and location of washers used as spacers
in the assembly.

To remove the interlock switch (4) Figure

jp^ 12, remove the two mounting screws and disconnect

the lead wires. Reassemble in the reverse order

and check. the switch adjustments as explained

under ADJUSTMENTS.

trip latch roller and that the latch spring

LATCH CHECKING SWITCH

is properly installed.

adjustments as e.^lainsd under ADJUSTMENTS.

MOTOR. RELAY AND LIGHT SWITCHES
Two or three switches (7) Figure 6, are
mounted in tandem as required by the application.
1.

Remove the opening spring per instruc

TRIP LATCH ROLLER BEARING

1.
2.

Remove two mounting bolts (4)from switch

Remove two cotter pins at ends of trip
latch roller shaft (8) Figure 13.
Partially remove shaft out right side of
frame until latch roller (6) is free.

Reassemble in reverse order with proper
spacing of washers. Be sure latch roUer
rotates freely.

tions below.

Check latch ad

justment as described under ADJUST
MENTS.

To remove the latch checking switch (5)
Figure 12, (when furnished), remove the twomount
ing screws and disconnect the lead wires. Re
assemble in the reverse order and check the switch

Reassemble parts in reverse order. Be
sure trip latch is aligned in center of

CLOSING LATCH

bracket (5).

Remove cotter pins at both ends of closing
latch shaft (9) Figure 6.

Remove spring and paddle (12).

center switch.

Remove set screws from latch (8).

Remove the two mounting screws of the

Move shaft (9) to left (away from frame)
by tapping lightly on the inside end of shaft.
Rotate shaft and continue tapping until
shaft is free. Shaft will push outside
needle bearing from housing.

Remove the two mounting screws of the
lower switch.

Remove the two mounting screws of the

upper switch.

Disconnect the lead wires of switch to be
replaced.

Reassemble in the reverse order and

check switch adjustment as explained

under ADJUSTMENTS.

TRIP SHAFT AND LATCH (See Figure 11)
1.

Remove spring discharge crank (3), manual
trip lever (11) and if furnished, the latch
checking switch operating arm (2) from
the trip shaft.

Disengage trip latch spring (1).

Remove three (3) cotter pins from trip
shaft.

4.
5.

MOTOR SUPPORT

2.
3.

Remove six 3/8" bolts (1) Figure 15, on
bottom and one 3/8" bolt on the right
side (not shown).

Remove four moimting bolts from motor
(not shown).

around the keyway on the shaft to avoid

damaging the trip shaft bearings.

Remove motor leads from the terminal
board.

the key.

Check for and remove any burrs raised

Remove the retaining ring (6) Figure 15,
and driving link (8).

latch is free of the key, then remove
6.

To remove motor support (9) Figure 15,
first remove the closing latch spring (12)
Figure 6.

Place a block between the trip latch (9)
and the left side of the mechanism frame.
Drive the trip shaft to the left until the

Check closing latch adjustments as* de
scribed imder ADJUSTMENTS.

Remove trip arm screw (10) andtrip latch
set screw (8).

Reassemble in reverse order putting bear
ing into frame last. Use a small piece of
tubing or pipe when inserting bearing to
assure proper alignment.

Remove the retaining ring (4) from the
eccentric (5).

Magne-Blast Circuit Breaker GEI-88763

Reassemble all parts of the motor support
in the reverse order and re-align it

properly as described under DRIVING

PAWL ADJUSTMENTS.

Remove the left hand closing spring as

described in CLOSING SPRINGS below.

CAM

Block the closing springs as described
in INSTALLATION.

Remove two set screws from ratchet

wheel (6) Figure 4 and remove wheel

3. Remove two mounting bolts (11), coil
support (16), and spacers.

from main shaft (5).

Remove two set screws from switch cam

Cut wires at the butt connectors and
remove coil.

(5) Figure 2.

Remove prop reset springs (4) Figure 5.

Remove two set screws from cam (8)
Figure 7, and move cam to the right on

the shaft as far as it will go. Slide the

Remove shaft out left side of frame.

Reassemble in reverse order using the

correct number of washers and spacers
to properly locate the parts.

Rotate the mechanism through a closing

Check the location of the cam

follower (15) Figure 7, on the cam (8).
If necessary, move the cam to correct

the alignment.

Complete the closing

operation and check the location of the

CLOSING SPRINGS

The closing springs (12) Figure 4, can be
removed as follows:

1. Charge the springs with the manual charg

ing wrench and apply the spring blocldng

device as described in INSTALLATION.

2. Discharge wrings by pushing manual
close button (9) Figure 5.

3. Rotate cam shaft (5) Figure 4, b-y using
the manual charging wrenchuntil the gap
between the spring (12) and the bearing

prop pin (4) on the prop (5). It should

block (7) is 2 inches or more.

be approximately centered.

4.
To replace the potential trip coil (6) Fieure
11, proceed as follows:

Remove trip coil support (5) and spacers.

Cut wires at the butt connectors and
remove coil.

When replacing the coil be sure to assem
ble the correct fiber spacers at the ends

Adjust coil locationto allowapproximately
1/4" of armature travel before latch
starts to move.

Butt connect wires and check operation

of solenoid electrically and mechanically

jeed as follows:

the opening springs witha suitable blocking

device.

OPENING SPRINGS
To remove the opening springs (4) Figure 4.
1.

Charge and block the closing springs as
described under INSTALLATION.

2. Push manual trip lever (8) Figure 5,

to be sure the opening springs are fully

discharged.

3. Remove iroper pin (1) Figure 4, and
lower pin (9).

primary contacts as described

/^To remove the closing coil (15) Figure 6

pushing the manual trip lever or block

4. After re^sembling springscheck the open

CLOSING COIL

5. Either discharge the opening springs by

proceed as follows:

before bolting support (5).

the top supports are free.

With the breaker in the open position
remove the two mounting bolts (7).
'

Lift both springs until they clear the lower
supports, then pull forward and down until

TRIP COIL

Butt connect wires and check that the
armature is not binding. Check coil for
electrical operation.

shaft to the left until key is fully exposed.

Remove key and check shaft for burrs.

Replace the coil and the correct number

of fiber spacers before bolting support.

under PRIMARY CONTACT GAP.

Magne-Blast Circuit Breaker GEI-88763

RENEWAL PARTS

It is recommended that sufficient renewalparts
be carried in stock to enable the prompt replace
ment of any worn, broken, or damaged parts. A
stock of such parts minimize service interruptions

ORDERING INSTRUCTIONS

data of both the breaker and the mech
anism.

c^sedby breakdowns, and savestimeand expense.

When continuous operation is a primary consider
ation, more renewal parts should be carried, the

amount depending upon the severity of the service

NOTE: The listed terms "Right" and "Left"

apply when facing the mechanism end of the breaker.

Specify the quantity, catalog number (if
listed), reference number (if listed), and
description of each part ordered, and this

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.

Always specify the complete nameplate

bulletin number.

3. Standard hardware> such as^crews, boltsjnuts, washers, etc., are not listed and
should be purchased locally.

For prices, refer to the nearest office
of the General Electric Company.

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In toe following tabulations are listed those parts of toe 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.

GEI-88763 Magne-Blast Circuit Breaker

RECOMMENDED RENEWAL PARTS FOR
TYPE ML-13 STORED ENERGY MECHANISM

USED FOR AM-7.2-500-5

(♦)

&-6(*), 1200 &2000 AMPERE

(*) SUFFIX LETTERS
Fig
No.
5

Spring Charging Motor - •*
48 V-DC

110 & 125 V-DC St 115 V-AC, 60 Hz
220 & 250 V-DC St 230 V-AC, 60 Hz
17

48 V-DC
110 & 125 V-DC

0137A7575P004

220 St 250 V-DC
115 V-AC. 60 Hz

0108B5565G002
0137A7575P005
0137A7575P002

115 V-AC, 60 Hz
230 V-AC, 60 Hz
24 V-DC
48 V-DC
15

Closing Coil - **

115 V-AC, 60 Hz
230 V-AC, 60 Hz
48 V-DC
7

7
1
12
4
8
2

5
1
1
1
1
1
2

006174582G001
006174582G015
006174582G002
006174582G010
006174582G014

064174582G34

Switch, Normally Open
Switch, Normally Closed
Auxiliary Switch
Closing Latch Spring
Prop Spring (Lower)
Driving Pawl Spring

Latchi^PawlSpi^-6

Prop Spring (Upper) (When Req'd)
B«

006174582G001
006174582G015
006174582G002
006174582G013
006174582G032
006275070G001

064174582G34

110 & 125 V-DC
220 V-DC
250 V-DC

6
6
5
6^
5
4
4

0137A7575P001

Potential Trip Coil - *•
110 & 125 V-DC
220 V-DC
250 V-DC

0105C9393P001
0105C9393P002
0105C9393P003

Relay -

230 V-AC, 60 Hz
5

Catalog No.

0456A0866P005
0456A0866P006

0161A4231P001
0137A9252P001
-D161A4241P001
•noi61A5909P001
00607123 IPOOl

Quantity Two (2) relays required on special control circuits. Check
breaker and connection diagram.
without closing spring discharge

-f

Relays on Early "-5" design.
0137A7575P043 - 48V-DC
0137A7575P042 - llOV-DC & 125 V-DC
0137A7575P041 - 220V-DC & 250 V-DC

0137A7575P045 - 235v-AC, 65 Hz

0137A7575P047 - 115V-AC, 60 Hz
Refer to breaker auxiliary switch for proper model
TypeSBM - 0137A9192G003
Type SB-12 - 0137A9192G011
30

• Indicates Revision

Magne«Blast Circuit Breaker GEI-86763

Fig.
No.

Ref.
No.

Ampere Type
Rating

Catalog No. for Type AM-7.2-500- *
-5

Operating Rod Assembly
Operating Rod Assembly
Operating Rod Assembly
Booster Cylinder
Flexible Connector (Right)
Flexible Connector (Left)
Flexible Connector (Left, Long)
Flexible Connector (Right, Long)
Flexible Connector (Left, Short)
Flexible Connector (Right, Short)
Insulating Plate
Arcing Contact Assembly
Primary Contact Finger Spring
Primary Contact Finger Spring
Primary Contact Finger ^rlng
Primary Contact Finger Spring
Primary Contact Finger
Primary Contact Finger
Primary Contact Finger
Primary Contact Finger
Throat Barrier Assembly
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact

0137A9164P003

Movable Primary Contact

0137A9164P004

0802B0742G004

0227A5306G001

Movable Primary Contact
^ Movable Arcing Contact

0213X0343G046

0213X0343G094

Tube and Piston Assembly

Upper Insulation
Throat Cooler Assembly (Right)
Throat Cooler Assembly (Left)

Upper Runner Insulation

—

0134C3595G001

E
•^1

GE.^86763 Mag|ne-Blast Circuit Breaker

TYPICAL elementary WIRING FOR MAGNE-BLAST BREAKER*;
OR
X

REQUIRED FOR 220a250V-dc
OPERATION ONLY.

CLOSING COIL (SPHG. REL. SOL'D)

CLOSING LATCH MONITORING
SWITCH

SM/LS
52

•nr

POWER SWITCHES

LATCH CHECKING SWITCH

SPRING CHARGING MOTOR

MUTUU

3-80 6-72

COMPANY.SWITCHGEAR BUSINESS DEPARTMENT.PHILADELPHIA. PA 19142

INSTftUCTIONS

GEK-41907

MAGIME-BLAST CIRCUIT BREAKER

Type AM-7.2-500-6, 2500 Amperes
The AM-7.2-500-6, 2500 ampere Magne-Blast circuit breaker is basically
the same as the 2000 ampere breaker except for the current-carrying and
associated parts required for the higher continuous current. All of the in
structions given for the 2000 ampere breaker in Instruction Book GEI-88763
are applicable for the 2500 ampere breaker.
The Renewal Parts required for the 2500 ampere breaker are the same as
those required for the 2000 ampere breaker except as tabulated below:

0258C0666P020
0619C0443P008
0828C0782P008
0828C0782P005
0121A5964P001

0236C0790P114
0236C0791P008
0108B1971P006
0108B1971P005
006442258P001

8
9
10

Figure 3

0213X0343G159
0137A9164P003

11
12

0137A9164P004

006176109P006

006591738P002
0132C2722P014

Rear Bushing Assembly
Contact Support
Arc Chute Support
Contact Finger Retainer
Spring Retainer
Spring
Spring Guide
Primary Contact Finger
Spacer
Washer
Stud

Contact Arm Assembly
Primary Contact
Primary Contact
Spacer (For Ref. 6)
Jumper on Rear Bushing
Baffle on Rear Bushing
* Not Illustrated

The information in this book supplements the
instructions covered in GEI-88763.

Instruction

book GEI-88763 is included as part of this book.

SWITCHQEAR PRODUCTS DEPARTMINT

MA©Mi== BLAST CiaCIJIT SaiAKiil
r1%

'Ay
•"31

Types
Ir^KT'f-

AM.13.S-150-3

AM-13.8-150A-3
Afta-13.S.250.3
AM-13.8-250A.3
Am.l3.8-500-3
AM-13.8-500A-3
Am.13.8-5GOi-S

OEiEBAl# ELEgTiiC
?HILAD£L?HU.

PA.

/
J'

GEH-S.

Transmitted Message; 1126 @1/21/9^ 7:54:56 AM
HTN17

4 50; CGEW8 0 5; 01; P; 3; 12 84 84; 0 0 0; ;; 9 8 0 721; E E ;
454;01;**********CLOSE JOB**********;;
-A

comEms

PAGE

INTRODUCTION

RECEIVING, HANDLING AND STORAGE

RECEIVING AND HANDLING

STORAGE

DESCRIPTION

INSTALLATION

ADJUSTMENTS
Primary Contact Wipe
ArcingContact Wipe

Prop Clearance ..!..!!!!!!!!!!ii||[

ClosingPlunger Ciearan'ce.. 111"1'1
Interlock Switch Wipe
111111'1
Control Device Adjustment. .111111111111111111111
Cut-off SwitchAdjustments . 11111111111111

•

Auxiliary Devices
Auxiliary Switch Linkage
FINAL LNSPECTION AND TEST

Hi-poteaUal Test
Control Power Checkl 1111111111111111111111111111

7
i
7

OPERATION

CLOSING OPERATION
OPENING OPERATION

a
t

TRIP FREE OPERATION

UMll 11111111 111 111111111111111111111111111'l 9

GENERAL MAKTENANCE

PERIODIC DJSPECTION
Ill 11111111111111111111111*1
Arc Chutes
1111111111111111111 ' "1
Breaker Contacts
111.111
Mechanism
11.. 11111111111111111111111111111
Bushings and Insulation
LUBRICATION
...lllll.'llllllllllllllllllllllllllllH""
Method of Cleaning Bearings
1111111111111111
Recommended Maintenance for Magne-blast Breakers Apolied to
Repetitive Duty

Failure to Trip
FaUure to Close or Latch Closed

H.l

Overheating

REPAIRAND REPLACEMENT
Arc Chutes
Trip Shaft Ball Benrings
Trto Latch Roller Bearings
Contacts

1..111111

Bushings
Trip CoU
InterlockSwitch

ORDERING INSTRUCTIONS

Latch Checking Switch

!i!!!lllllllllllllllllllllllllll n

INTRODUCTION
The magne-blast circuit breaker is
the removable interrupting element for use
in vertical-lUi metal-clad switchgear, to

not exceed its rating, nor should it be
called upon to operate at voltages or cur
rents greater than those given on the nameplate. Since this book is written to cover
several ratings of breakers that are of the

interrupted in air by sufficiently elongating
ami cooling it. This is accomplished by

provide reliable control and protection of

means of a strong .magnetic field dial
lengthens the arc and forces it into in

power systems. Among the many advantages

timate contact with cool dielectric material.

of metal-clad switchgear are added pro
tection to equipment and personnel, com

A sturdy, reliable operating mechanism

pactness, simplified installation and re

the use of Self-X insulation reduces fire

trations will be typical, unless otherwise

duced maintenance.

haz.irds to a mini.mum.

specified.

features

the

In keeping with these

magne-blast breakers

same general design, all instructions will
bo of a general character and all Illus

assures low maintenance and long life, and

are

designed for interchangeability and maneu
verability, together with reliability and low

PROPER fNSTALLATION AND MAIN
TENANCE ARE NECESSARY TO INSCRE
CONTINUED SATISF.^CTORY OPERATION

maintenance requirements.

The AM-13.8 magne-blast breaker is
available in a number of current ratings.
Refer to the brea.ker nameplate for tiie
complete rating Informiation of any par-

The magne-blast circuit breaker oper
ates on the principle that an arc can be

ditions to be imposed on the breaker must

ticul.tr

breaker.

OF THE BRE.\KER. The following instruc
tions will provide complete information for

placing the magne-blast breaker in service

The short circuit con

and for maintaining satisfactory operation.

RECEIVING, HANDLING AND STORAGE
RECEIVING AND HANDLING
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

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

with the transportitlon company and the
nearest General Electric Sales Office should
notified.

It is expected that due care will be
exercised during the unpacking and instal

lation of the brewer so that no damage will

occur from careless or rough handling, or
from exposure to moisture or dirt.
A
nail puller should be used to open the
crates, and care should be exercised to
prevent tools from striking either the

2. The breaker should be stored in a

It is recommended that the breaker be

put into service immediately in its perinaii'.'iit location.

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

If this is not possible,

the following precautions must be taken to
insure the proper storage of the breaker:
1. The

breaker

K the breaker is stored for any length
of time, it should be inspected periodic
ally to see that rusting has not started and
to insure good mechanical condition. Should

should be carefully

protected against condensation, preferably
by storing it In a warm dry room, since
water absorbtion has an adverse effect on

the breaker be stored under unfavorable

the insulation parts.

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

Circuit breakers for

outdoor metal-clad switchgear should be

stored in the equipment only when power

DESCRIPTION
The magne-blast breaker is composed
of two major parts, the breaker element and
the operating mechanism.
The breaker
element comprises threesimllar 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 primary connections to the as
sociated metal-clad equipment are made
through the primary disconnect studs.

The MS-13 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 con
trol device (7). The control device also

permits trip-free operation (tripping the
breaker at any time during the clo.<3ing

operation) and prevents solenoid pumping
(reclosing) after a trip-free operation.
The breaker can be opened electrically, by
remote control, or manually, by means of
the manual trip device (6). All secondary

I
5'

1. Secondary Coupler
7, Auxiliary Soiich

3. Position Indicator

4. OpcninK Sprinc Unit
5. Operation Counter
6* Uicnufll Trip

u i i :

7. Control Device
8. Control Device

Pluncier Guide
9. Closing Solenoid

9 4^.

Ju..

connections from the breaker to the mctal-

d unit ore made through the coupler (1).

Fig. I

HS-13 Operating Nechar.tpa

TbeM inatrvdibm do not purport to cover off detoi/i or vortoliont in oquipmant nor to provide for evsry pouAlo
contingency to i>e met in connection with inrtallaiion, operation or mointenonce. Should furlhitr infomcHon be detirad

or ihouldpartizular probfeoii orito which ore not eovei^ tuffkionlif for tho purchoxr'r pwipoMt, the mctter ahowfd
bo referred to the Ganaral Elaetrk Company.

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.

STORAGE

be made for any damage sustained in trans

it. If injury or rough handling is evident,
a damage claim should be filed immediately

is available and the heaters are in opera
tion to prevent condensation.

crate or any part of the bre.aker. Loose
parts associated with the breaker are al

GEH-2004 Magne-blast Circuit Breaker Type AM-13.8-3

IfKHir

« A

J
; r
w

1» Qosing Araature Cover

Prioarjr Contact Wipe

2. Hmdle

3* llointenance Operating Device
4. Seleese Valve

Fig. 2

Arcing Contact Wipe

l«Stationary Primary Contacts
2.!iiovable Primary Contacts

Method of Mounting Maintenance
Operating Device

3.Buffer Block

4.Stationary Arcing Contacts

Fig. 3

5.Uovabie Arcing Contacts
6.Upper Arc Bunner

Contact Adjusteentc

^A-7 8--^
1. canting Rod

S. Stationary Prinsry

2. Operating Rod

Contacts
6- Movable Prisary
Contacts

3. Adjusting JAit
Che^ Mut

Adjustable Coupling for Making

^i_ ^-'1

Pritsary Contact Wipe Adjustsent

a-'5
=j

\/LH
y
f- - i\V''^
i i'
/\|-

III
t. Main Oper. Shaft

11* Opening Spring

2. Main Crank

Routing

3e Trip Shaft
4. Trip Letch

12. Opening Spring.

!• Interlock 9iaft 5* Lstch Oiecking

5- Trip Latch Stop

a. Interlock Seitch
Seitch Ara
*to
6. Boiler

13. Opening Spring.

6. Trip Boiler
7. Positior Indicator

8®II®r

4. Interlock Seitch

7, thatch Checking
Seitch

8' Trip Shaft

Fig. 6

Interlock Switch «d Latch
Owcking Switch

8. Qevis

9. Adjustable Stud
10. Closing Pin

Fig. 5

18. Pialon Ring
19. Set Screw
20. Shiots

s
a

14. Qosing Boiler
15. Prop
16. Closing Coil

23. Amature Guide
Bolts

22. Stop fiiiR!.ls (2) to the
bottom of the elevating ba.- USl should be
10-7/32" i 1/16". To change this adjust
ment, add or remove washers 13).
AUXILIARY SWITCH LINKAGE „ „

(FURNISHED SPECIAL ON 13.8-150A,
250A, 500A)

Refer to Fig. 10. With the breaker in

In order to trip properly, the clear
ance between the trip bolt (11) and tiie uip

the open position, the distance from the
centerline of the front bushing (1) to the
center of tlie switch operating pir (3)shou!c.

can be altered by releasing the checs nut

setting, loosen the locking nut (6). remove
the pin (4) and turn the clevis (5). Reas

plate (9) should be 1/32" to 1/16". This
and screwing the trip bolt '.11) in or cat of

the reset arm (8).

12-1/4" as shown.

To change this

semble and check adjustments.

BEFORE
MANUALLY OPERATING
>«!«!!!The control device, make certain

^kat all control power to the
breaker has been disconnected,

manual OPERA'nON OF THE CONTROL
DEVICE WITH CONTROL POWER CON
NECTED WILL ENERGIZE THE CLOSING
COIL AND PRODUCE A CLOSING OPER
ATION.

CUT-OFF SWITCH ADJUSTMENTS

(13.8-150A-3, 250A-3, 500A-3)
Refer to Fig. 8.

The operating 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 l)e 1/32" to 1/16

clearance lietween the depressed roller of
the switch and the striker (3).

Washers

4/:

(4) should be added or removed if neces

sary to correct adjustment

..r2' isi,

AUXILIARY DEVICES
I.ateh Checking Switch Wipe

Referring to Fig. 6, rotate the trip
shaft (8) manually clockwise to release the
latch checking switch arm (5). The point at
which the contacts make can be determined
with a circuit continuity tester such as a

Ujdst indicator or bell set To obUin ad
justment on the latch checking switch (7i,

bend jhe latch checking switch arm (S).

Front Difconnect Stud

9. Trip Plate

The roller and crank on the latch checking

Interlock Bolt

W. Spring

travel after final adjustment.

naeher*

H- Trip Bolt

Connect in;; Rod

Impact Trip, Current Trip, Capacitor Trip,

Seiet Plete
Beiet Boiler

13. Bleveting Bar
14. Impact Trip Plate

Ueln Operotin* Shaft
Beeet Aro

IS. Trip Letch
16- Trip Bolter

switch (7) should have 1/32 to 1/16 over-

-^^"•'^'iand Undervoltage Trip Devices

W-

Clevis

17. Trip Amoture
18. Trip Lever
19. Undervoltage Trip Banner

20. Mjusting Rod
21. Manual Trip Button

22. Trip Setting Plete
23. Undervoltage Device

Fig. 9 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)

Fig. 9

Adjustnoflts On Current Trip Device And Undervoltage Trip Oevice,
Shown ftith The Breaker In The Closed Poaition

\aszsra

Magne-blast Circuit Breaker Type AM-13.8-3

'\\uxUiary Switch
The auxiliary switch is mounted on the

right side of the operating mechanism (2),
Fig. 1. The shaft of the position indicator
operates the auxiliary switch shaft which

o. Auxiliary switch linkage:
250A, 500A) 12-1/4".

(ISOA,

p. Auxiliary switch "a" contacts close
when breaker primary cor.iact gap
is 1" or greater.

opens and closes the "a" and "b" contacts.

(The "a" contacts are open when the breaker
is open and the "b" contacts are open when
the breaker is closed). The "a" conticis
The "b" contacts

need only to be checked to see that they
are qicn when the breaker

is closed.

The capacitor trip should be capable
of tripping the breaker as late as 25 sec
onds after the control voltage is removed.
If the auxiliary devices do not perform in
accordanre with these' specifications, a
careful examination should be made for

defective parts.

2. Check all nuts, washers, bolts, cotter
pins, and terminal connections for tight

CONTROL POWER CHECK

ness.

should close when the breaker primary
contacts are 1" apart.

GEH-2004

After the breaker has been closed and

3. Inspect all wiring to make sure that nu
damage has resulted during installation,
and test for possible grounds or short
circuits.

opened slowly several times with the main
tenance closing device and the mechanism
adjustments checked as described above,
the operating voltage.<5 should be cheeked

at the closing coil and trip coil terminals.
4. See that ail bearing surfaces of the
mechanism have been lubricated. Refer
to the section on LUBRICATION.

5. Operate the breaker slowly with the
maintenance closing device and note
that there is no excessive binding or

For electrical operation of the breaker,
the control power may be either an alter
nating or direct current source. Tbe oper

ating ranges for the closing and tripping
voltages are given on the breaker nameplate. Ordinarily, standard ranges apply
which are as follows:

friction and that the breaker can be

moved to the fully opened and fully closed
positions.

1. Front Bushing

4. Pin

2. Fork Lover
3. Operating Pin

S. Clevis
6. Check Nut

If the breaker had been stored for a

breaker Is placed in service.

A standard

60 cycle high potential test at 27,000 volts

with the Breaker in the Open Position

RMS will normally indicate whether the
breaker is satisfactory for service. With

FINAL INSPECTION AND TEST

the breaker contacts in the fully opened
position, apply the high potential to each

1. For ease in reviewing the adjustments,
the following are recapitulated:

one minute with all other terminals and the

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

tential tests are made on organic insulating
materials, these materials should be in

b. Arcing
contact wipe: 5/16" or
greater (gap at primary contacts).
5-1/4" +

trip latch resting against stop pin.

e. Prop clearance: 1/16" ^ 1/32".
3/16".
1/32"

switch overtravel:

1/32" min.

After high po

spected for visible leakage current paths,
and necessary action must be taken to
replace insulation that may have been af
fected by moisture absorption. The high
potential test

is also recommended for

service and stored over an extended period
of time under unfavorable atmospheric
conditions.

On breakers that are equipped with

auxiliary devices such as a current trip,
undervoltage 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

undervoltage trip device should trip the
breaker when the control voltage drops

1/32" -

below 30 to 60% of rated voltage, and it
should pick up at 80% of the control voltage

j. Latch checking switch wipe: 1/32"

or less. An adjustment plate is provided
on the front of the tmdcrvoltage trip device
as an aid in obtaining the desired setting.

i. Cut-off switch overtravel:
1/16" (150A, 250A, 500A).
to 1/16" overtravel.

k. Impact trip roller wipe:
1/32".

1. Impact trip bolt clearance:

1/8" +

3/64"

+ 1/64".

breaker frame grounded.

AUXILIARY DEVICES

f. Closing plunger clearance: 1/16" to

device

terminal of the breaker individually for

m. Undervoltage

NOTE: Where repetitive operation is re
quired from a direct current source, the

closed circuit voltage at the closing coil
should not exceed 115 v d-c and 230 v d-c

at the nominal voltages of 125 v d-c and

250 V d-c respectively.
For a-c operation, copper-oxide rec
tifiers, mounted elsewhere in the mefcilclad unit, are used. A tapo.-jd 1-1/2 ohm
resistor is provided in each rectifier circuit

to control the d-c voltage. The resistor
setting should be adjusted so thatLhe .iosed

circuit voltage at the b.-eaker closing coil
terminals is 110 to 120 volts d-c. Where

repetitive operation is required, the voltage
should be set at 103 to 115 volts d-c.

breakers which have been removed from

d. Trip latch wipe: 3/16" to 1/4" with

h. Control

TRIPPING
RANGE

250 v d-c

that the insulation be checked before Use

g. Interlock switch wipe:
1/16" overtravel.

RANGE

stallation is repainted immediately.

long period of time, It Is recommended

Fig. 10 Auxiliary Switch Linkage Shown

c. Primary contact gap:
5/16" - 1/8".

CLOSING

6. See that any place where the surface of
the paint has been damaged during in
HI-POTENTIAL TEST

NOMINAL
VOLTAGE

trip hammer clear-

ance: 3/64" + l/64".

n. Plunger interlock: 10-7/32" ♦ 1/16".

NOTE: When checking the pick-up value of
the undervoltage device, apply a voltage
equal to 80% of normal control voltage to
the undervoltage device coil. The device
should pick up at this value. Co not in

Resistor Setting for

• A-c Volts

(Closed Circuit)

Each Resistor
Summer
Winter

214-226
224-236
234-246
244-250

♦ A-e volts as measured across the rectifier

and a-c series resistor.

The preceding tabulation is included as
a guide for adjusting Ihe resistors for the
particular combination of ambient tem|>e.'ature and a-c supply voltage.
Summer
settings are used where ambient tempera

tures are normally above freezing (32''F).
It is necessary to u.se winter settings where

the ambient tem^rature may drop to 20°F

or less at any time.

For a more detailed

e^Ianation of copper-oxide rectifiers for
circuit breaker application, refer to In

crease the voltage gradually on this coil
as it will overheat the coil, producing a

struction Book OEl-11306.

false reading, and may damage the coil if

To check the d-c voltage at the closing
coil terminals, proceed as follows:

excessive overheating occurs.

GEH-2004

Magne-blast Circuit Breaker Type AM-13.8-3

Close the breaker tay manually oper

ating the control device, Fig. 0, Hold the
co.itacts in the closed position and re.td
the d-c voltage at the closing coil terminals.

To de-energize the circuit, release the

d-c voltage, or increase the series
resistance to decrease the d-c voltage.
Recheck voltage at the closing coil.

2. D-c control power source - Check volt
age at the source of power and line

control device.

drop between the power source and the
DO NOT MAINTAIN VOLTAGE ON
THE CLOSLNG COIL ANY LONGER THAN

THE FEW SECONDS REQUIRED TO READ
THE VOLTMETER.

These coils are de

signed lor intermittent operation and will
be damaged by prolonged current flow.
If the closed circuit voltage at the ter
minals of the closing coil does not fall in

the specified range, proceed as follows:

1. A-c control power source - Decrease
the series resistance to increase the

breaker.

When two or more breakers, operating
from the same control power source, are

clad unit. It is also possible to trip the
breaker manually by pressing the manual
trip button l6). Fig. 1.
When all the loregolng inspection de
tails have been checked, the breaker may
be safely placed in service. Before the
breaker is finally raised into position in
the mctal-clad unit, rub a small amount of
G.E.

silvered portion of t.he breaker studs to

required to close simultaneously, the closed
circuit voltage at the closing coil of each
breaker must fall within the specified

form a thin coating for contacting purposes.

limits.

bination

NOTE:

This breaker mechanism com

is designed only for electrical

closing when in use.

NEVER ATTEMPT

Electrical closing or opening is ac
complished by merely energizing tlie clos

IN SERVICE, for under such conditions,

ing or trip coil circuit. Control switches
are provided for this purpose on tlie meul-

sufficient closing force and speed cannot
be applied.

hLAia'AL CLOSING WITH THE BREAKER

OPERATION
CLOSING OPERATION

?!:

The closing operation of the breaker
is primarily controlled by the control de

vice, Fig. 11, mounted on the operating
mectianism. ^e closing sequence t.s ini

.Vi.

tiated from a control switch mounted on
the door of the metal-clad unit or at a

remote operating station. Operation of the
Closing control switch energizes the pickup
coil of the control device.

As the control

device closes, seal-in contacts shunt the
closing control -switch to allow tiie opening
of the closing control switch contacts with
out affecting the overall closing operation.
This type of arrangement assures com
plete closing of the breaker with only
momentary contact of the closing control

Operation of the control device ener
gizes the breaker closing coil by closing

the main control device contacts (5 and 6),
Fig. 11.

Once the control device'contacls

are picked up, they are electricaly held
In the closed position until the bre-oker

closing operation is completed. Energizing
the breaker closing coil raises the arma
ture (6), Fig. 12, which in turn lifts the
closing roller (4) through plunger (14).
This motion is transmitted through the
mechanism linkage and rotates the main
crank (1), closing 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.
During the closing operation,
the opening springs (9 and 10) are com
pressed in readiness lor an opening oper
ation.
Air trapped above the armature
acts as a dash pot to absorb the energy of
the mechanism as it approaches the end of
its stroke.

When the armature is near tlie end of

Its stroke, the control device plunger (5),
Ftg. 22, mechanically trips the main control
device contacts, de-energizing the closing
coll and allowing the armature to return by
gravity to its original position. The 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

>!^s^held In the closed position through andafter

^•Jie breaker closing operation, the control
^cvicc linkage will remain picked up and be
unable to

reset to prepare for another

1. Shuntinc and Aiti-pimp Svitch

6. Uovoble Contact Assentbiy

3. Seal-in Saitoh

7. Ara
8. Arc Qiute

3. Operating Coil

9. Trip Lever
10. Plunger Guide

4. Crank

5. Stationary Contact Assenbly

Fig. II

Control Device

breaker closing operation. This arrange
ment insures that "pumping" of the breaker
will not occur during a trip-free operation.
The operating sequence
for those
breakers designed for MI-6 nictal-clad
equipment is similar to thaidescribedabove
except that a relay mounted elsewhere in
the metal-clad unit replaces the tonirol
device.
Also, a cut-off switch (Fig. 8)
is used to replace the mechanical trip ar
rangement of thecontruldevice. The cut-off
switch energizes an auxiliary relay to
de-e.nergize the main relay.
The closing speed of the arcing contact
should be 7 to iO feet per second icr the
150,250 MVA breakers and 9 to 13 feet
per second for the 500 MVA breakers with
rated closed circuit voltage at the closing
coil terminals.
These speeds represent
the average speed of the movable arcing

contact from a point 1" before the lip is
tangent to the lower surface of
upper
arc runner to the tangent position.

OPENING OPERATION

An electrical opening operation is ini
tiated by energizing the trip coil. This
is accomplished either by actuating the
Ojiening 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 ener

IJ I

gizing tliu trip coil, the trip plunger ro

tates the trip latch (2), Fig. 12, causing
the operating mechanism linkage to col
lapse. The energy stored in the opening
springs (9 and 10) is thus released, opening
the breaker. I>jring this operation, the trip
coil circuit is de-energized, and upon com
pletion of the opening operation, the oper
ating mechanism is returned to its normal
position, ready for closing.

As the breaker opens, tlie main conUcts part first, shuntingthc current through
the arcing contacts.

An arc forms as the

arcing contacts part (see Fig. 13).

the movable arcing contact (27) is with-

Magne-blast Circuit Breaker Type AM-13.8-3

GEH-2004

the arc is forced outward along the di
verging arc runners, the magnetic field is
progressively increased with the addition
of each coil in the circuit.

At the same time, the arc is being
forced into the arc chute (8) which is com

posed of a series of gradually interleaving
1. Unin Critnk

2.
3.
4.
5.
6.

Trip Latch
Trip Roller
Qostnii Roller
Piston Rine
Closing Anrature

AfTrotute Guide

8.
9.

Spriofi: Retainer
Opening Spring,

Bolts

Inner
10. Opening Spring
Outer

11.
12.
13.
14.

Closing Pin
Prop
Closing Coil
Closing Plunger

insulating fins. These fins, which project
alternately from the two opposite inner
surfaces of the chute, elongate the irc
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

resisunce reduces both the magnitude and
the phase angle of the current, and at an

early current zero Die arc path is so iong
and the gases produced by the arc so cooled
that the arc cannot re-establish itself, and
interruption occurs.

Manual tripping follows the same pro
cedure except that instead of energizing
the trip circuit, the manual trip (6), Fig. 1,
is used.

Rod

TZ777

The opening speed of the arcing con
tact should be 10 to 15 ieet per second at

/777V!

rated control voltage.

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.

Fig. 12

Cross Section of M^I3 Operating Mechanism in the Open Position

TRIP-FREE OPERATION

drawn 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 I'Oiiit, a stream oi air
is emitted from th- ' ooster tube (28) and

to draw the arc away from the arci.ng con
tacts. The 150 and 250 MVA interrupter
contains three upper niagiieiic blowout cuil?.
and one lower blowout coll each individually
connected in series with its respective

forces the arc onto the lower arc runner

section of arc rur..ncr.

(lOj. Establishment of the arc on the run
ners automatically inserts the first blowout

terrupter

coil into the circuit, introducing a magnetic
field between the pole pieces which tends

and three lower blowout cuiis each

individually connected in series with its
respective section of arc runner.
As

If the trip coil circuit is energized
while the 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
tite breaker to re-open. The closing arm
ature (6) completes its closing stroke,
but the closing coil is de-energized at the
end of the stroke, and the armature is
returned to its original position by gravity.

GENERAL MAINTENANCE
^.Dependable service and safer power
equipment are contingent upon the unfailing
performance of the power circuit breaker.

To maintain such service, it is recom

mended that a definite inspection and main
tenance 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 lubrication of parts
subject to wear is also vitally important
for the successful operation of the breaker.
BEFORE ANY MAINTENANCE WORK

B PERFORMED, MAKE CERTAIN THAT
ALL CONTROL CIRCUITS ARE DE-ENER
GIZED AND THAT THE BREAKER IS RE
MOVED FROM THE METAL-CLAD UNIT.
DO NOT WORK ON THE BREAKER OR
MECHANBM WHILE
IN THE CLOSED
POSITION UNLESS THE PROP AND TRIP
LATCH HAVE BEEN SECURELY WIRED OR
BLOCKED TO PREVENT ACCIDENTAL

operations which occur from time to time.

(Iterating experience will soon csublish a
maintenance schedule which will give as
surance of proper breaker condition. On

installations where a combination of fault

duty and repetitive operation Is encountered,
an inspection is recommended after any

severe fault operation.

in an inspection, and a number of general
recommendations.

ARC CHUTES

It is not necessary to inspect the arc
chutes unless there is evidence of rfamai^e

or if the arc chutes are removed for any
reason. When inspecting an arc chute, it
should be disassembled and the following
points noted:

1. Scale lorrced over the surface of the arc

TRIPPING.
PERIODIC INSPECTION

The frequency of periodic inspection
should be determined by each operating
company on the basis of the number of oper

ations (including switching), the magnitude
.of currents interrupted, and any unpsuai

The following in

structions list the main points to be included

operation of the device in any way and
should be disregarded. Small brol-.en
corners on the exhaust end of the chute

will not interfere with its performance
and can also be disregarded.
3. if the arc chute has suffered any mech
anical injury due to dropping or ac
cidental striking, resulting in the actual
breaking off of fins, replacement of the
chute will be necessary.
BREAKER CONTACTS

By removing the box barrier the mov
able and stationary primary contacts and
the movable arcing contacts can be inspect
ed. The stationary arcing contact.s c.an be
inspected only after removing the arc chute
assembly, as explained under REPAIR AND
REPLACEMENT.

If the contactsare burned

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

chute must not be removed, but loose
particles collected in the chute should

After completing inspection of the con
tacts, check the contact adjustments as

be blown out.

specUied under INSTALLATION, ADJUST

Cracks which have formed in the fins

MENTS.
MECHANISM

of the arc chute are to be expected in
ceramic materials of this type when
subjected to the severe heat of an arc.

check for loose nuts or bolts and broken

These cracks do not interfere with the

retaining rings.

A careful inspection should be made to

All

cam, roller, and

GEH-2004

Ma.^e-blast Circuit Breaker Type AM-13.8-3

ir^l

♦) i
1. Box Sorrier Catch
. 2e Box Barrier
3* Arc Chute

II. Pole Pieces
12. Front Bushing
13, Bear Bushing

4* Arc Skmer. Ui;»per
5. Bio« (Xit Coil. tJ^per
6. Elev Out Core, Upper
7.
6.
9.
10,

14. Upper Roritontal Barrier
IS. Bain Operating Crank
16. Arc Otute Support

Vovable Arcing Omtact
Arc &jnner. Lover
Blov Out Coil, Lover
Blov Out Core, Lover

17.
18.
19.
20.

Fig* 13
10

Spring Betaaner

91. Stationary Priaary Contact
22. Ilovable Privary Contact

23. Bovable Contact Am Asseobly
24. Cup Bearing
25. Booster Tube
26. Front Vertical Barrier
27. Check Nut

Lover Horizontal Barrier
Operating Sod

28. Connection Bar

Stationary Arcing Contact

30. Side Barrier

29. Booster Cylinder and Piston

Cross Section of Breaker Polo Unit

Magne-blast Circuit Breaker Type AM-13.3-3 GBH-2004

^,.-~4atch surfaces should be inspected for any

Part

Yldcnce 'of damage or excessive wear,

Lubrication at

Alternative Lubrication

Maintenance Period

(Requires Disassembly)

Lbricate the mech^ism as outlined below,

uien, using the maintenance operating de
vice, open and close the breaker several

Ground surfaces such as

Wipe clean and apply

times to make certain that the mechanism

cams, rollers, latches, etc.

D50H15.

Check the mechanismadjustments as speci

Sleeve Bearings

Very light application
of light machine oil

Remove pins and links
and clean as per clean

SAE-20 or -30.

ing instructions below.
Apply DSOHIS liberally.

Light application of
light machine oil

Clean as per cleaning

Type Ball, Roller and

should be kept clean and unmarred to pre

Needle Bearings

SAE-20 or -30.

vent moisture absorption. If the insula
tion surface should become damaged, it

Sliver Plated Contacts and

Wipe clean and apply

repack with DSOHIS.
Wipe clean and apply

Primary Disconnect Studs

No lubrication required.

Wipe clean and apply

2. Loose rings between
bushing and contact

No lubrication required
except on highly repetitive

Replace rings showing
evidence of excessive

duty.

wear.

.No lubrication required.

No lubrication required.

operates freely throughout its entire stroke.
fied under
MENTS.

INSTALLATION,

(Mechanism and Breaker
Linkage)

AJ3JUST-

Check ail terminal connections.

BUSHINGS AND INSULATION

Removable Seal and Open

The surface of the Seif-X bushings

sl\,ould be sanded and cleaned, and should

refinished

(GE-1170)
(GE-1202).

with either clear varnish

or
clear Giyptai*
resin
Allow to dry smooth and hard.

CONT.ACT ARM HINGE
ASSEMBLY

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 t>e installed to
insure dryness.

In order to maintain reliable opera

tion, it is important that ail circuit breakers
properly lubricated at ail times. During
assembly at the factory, ail bearing sur
faces, machined surfaces, and ail other
parts of the breaker and mechanism sub
ject to wear have been properly lubricated
using the finest grade of lubricants avail
able.
However, even the finest oils and
greases have a tendency to oxidize with
>.ge, as evidenced by hardening and darkeng in color. Elimination of the hardened
bricant is essential for the proper operauon of circuit breakers.
Also frequent
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 disturbances
which might be mistaken for more serious

NOTE - PS0H47 supersedes D50H28.
Fig. |i|

Lubrication Chart

indicated in the lubrication chart, the fol
lowing procedures are recommended:

If it is desirable to leave the bearings in

Sleeve Bearings

alcohol such as is used for anit-freeze

Du Font Zerone are satisfactory for this;

clean' petroleum solvent or similar

cleaner.

DO NOT USE CARBON TETRA-

CHLORIDE. 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.

. A definite lubrication schedule should

The t)earings should be first removed
from the mechanism and disassembled l>y

local conditions.

the rendoval of the seals or inner race in

cated at each periodic inspection and also

the case of needle bearings. They should
then be placed in a container of clean petro

whenever it is overhauled, in accordance
with the lubrication chart, FJg. 14. It is

leum solvent or similar cleaner. DO NOT
USE CARBON TETRACHLORIDE. If the

also recommended that all circuit breakers

grease in the l)earings has t>ecome badly

be operated at regular intervals to insure
the user that the equipment is operating
freely.

oxidized, it may be necessary to use alco
hol (type used for thinning shellac) to

The lubrication chart is-divided into
methods of lubrication.
The first
method outlines the maintenance lubrication

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 onto the bearings
are inducive to corrosion. If the bearings
are touched, the contamination can t>e re

two

which should be performed at the time of
periodic maintenance, and requires no dis
assembly. The second method outlines a
lubrication procedure similar to that per
formed on the breaker at the factory, but

should be used only In case of a general
overhaul or disassembly for other reasons,

remove it.
Ordinarily, by agitating the
bearings in the cleaning solution, and using

moved by washing in alcohol. After the
bearings have t>ecn thoroughly cleaned,
spin them in 'clean new light machine oil
until the cleaner or solvent is entirely

or if the operation of the breaker becomes

removed.

slower.

then repack them immediately with G. E.
Lubricant DSOHlS Iteingsure all metal parts

General Electric Lubricants D50H15

and D40H47 areavailable in 1/4# collapsible
tubes. It is so packaged to insure clean••'^ess and to prevent oxidation.

Whod of cleaning bearings
Wherever cleaning is required.

Even then the bearings

should be removed from the alcohol within

twenty-four hours.

be sdt- iq> taking into consideration the
frequency of operation of the breaker and

worked out, the breaker should be lubri

the alcohol for a longer time, an inhibited
should be used.

The pins should be removed and all

and Needle Bearings

Until such a schedule is

main in the alcohol more than a few hours.

old oxidized grease removed by immersion

Removat)le- Seal and Open Type Ball. Roller

trouble.

instructions below and

Allow this oil to drain off and

are greased. The removable seals should
then l)e 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 re

• Registered Trade-Mark of General Electric Company

purpose.

Esso Anti-Freeze and , "

Precautions against the toxic

effects of the alcohol must be exercised

by wearing rubber gloves and t>y using the
alcohol in a well ventilated room; exces

sive exposure to the fumes is sometimes
unpleasant to personnel. Washing the bear
ings in light oil and draining should follow
immediately, then apply the lubricant.
RECOMMENDED MAINTENANCE FOR
MAGNE-BLAST BREAKERS APPLIED TO
REPETITIVE SWITCHING DUTY

Magne-biast breakers applied to re
petitive operation such as switching arc

furnaces, capacitors and motors should be
serviced and maintained according to the
following schedule:
A. Every 2000 Operations, or Every Six
Months - Whichever Comes First

1. Remove the box barriers and oper
ating mechanism covers.

2. Wipe all insulating parts, with a clean
dry cloth, tncltiding the tnishings,
clean of smtdce deposit and dust, also
the inside of the box barriers.

3. Primary Contacts - Inspect the con
dition of the stationary contact fin
gers and movahie contact blocks.
Badly pitted or burned contacts should

be replaced.

(Note:

Burned pri

mary contacts indicate the protable
need for arcing contact replacement).
If the contact surfaces are only
roughened or galled, they should be
smoothed with crocus cloth or draw

filed.

After contact dressing thef:-''''-'

contacts shoidd be greased lightly
with D50H47.

GEH-2004

Magne-blast Circuit Breaker Type AM-13.8-3

of arc erosion.

vice should be inspected for wear

and possible replacement.
8. Lubricate

the

breaker

operating

mechanism in accordance with the

table under.paragraph heading"LDB-

the fins of the arc chute sides.

insulation.

10. After the breaker has been serviced,
it should be slowly closed and opened
with the maintenance closing device
to be sure there is no binding or
friction and that the breaker contacts

can move to the fully opened and
fully closed positions. Its electrical
operation should then be checked
using either the test cabiqet or the
test couplers.
B.

After Every 10.000 Operations

1. In addition to the servicing done each
2,000 operations, the arc chutes
should be removed from the breaker

and disassembled to permit a de
tailed inspection of insulation, blow
out coils, arc runners and assem

blies which are contaminated by arc
products.
2. All areas in the throat area of the

arc chute should be thorou^y
cleaned by using sandpaper. This
cleaning should be performed any
time

the

arc chute is removed.

The arc chute fins should not be
cleaned.

Whenever the arc chute

is removed, loose dust and dirt
should be blown out before replac
ing arc chutes.
3. The blow-out coils should be care

fully examined and if the insulation
has been cracked, shrunk or eroded
from arc action and heat so that the

This

is to be expected with ceramic mat
erials when subjected to the high heat
of an arc and may be disregarded
unless they are long and preser.t a
possibility of fin sections breaking

completely off.

Small broken cor

ners on the exhaust end of the arc

chute will not Interfere with its per
formance and canalsobe disregarded.
Every 20.000 Operations or Approxi
mately Every Five Years - Whichever
Comes First

1. At this time tlie breaker should be

given a general overhaul and all ex
cessively worn parts in both the mech
anism and breaker replaced.- Such
wear will usually be indicated when
the breaker cannot be adjusted to in
struction book tolerances. This over

RICATION".

9. Inspect all wiring for tightness of
connections and possible damage to

binding

sticking

nections are tight.

edn and/or eroded from arc action
shotdd be replaced.
NOTE: Fine cracks nuy develop i.i

2. Mechanism
REMEDY:

7. Any parts damaged or severely burn-

nism should be carefully inspected
for loose nuts, bolts, retaining rings,
etc., all cam, latch and roller sur
faces should be inspected for damage

REMEDY: Lubricate complete me

caused by being out of adjustment.

ized and cannot be satisfactorily
cleaned should be replaced.

6. The breaker and operating mecha

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

in good condition and that their con
6. Insulating material that is carbcs-

made as described under "Adjust

F.AILURE TO TRIP

chanism.

5. Check the stationarary arc contacts
to assure that the arcing contacts are

ments".

7. The main contacts of the control de

die trouble:

t)e checked for tightness.

and replaced when any part of their
area has been reduced to 25% cf t.*.e
original metal thickness as a resuit

the breaker and mechanism

bottom of the stationary contact sup
port should beinspectedforpossible
need of replacement.

should be replaced. All connections
4. The arc runners should be inspected

adjustments as summarized under
"Final Inspection & Test".
The
necessary readjustments should be

or excessive wear.
The buffer
blocks and their retainers on the

types of distress that mightbe encountered!
together with suggestions for remedying

should

cumstances.

5. Check

sulated from each other the coils

turns of the coils are not fully in

4. Arcing Contacts - When the arcing
contact wipe Is less than the mini
mum spedUied under "Adjustments",
the conta'cts should be replaced. The
contacts should be inspected tor un
even wear and/or damage using a
mirror to inspect the stationary con
tacts. Normally it wiil not be nec
essary to remove the arc chutes
for this 2000 operation servicing un
less inadequate wipe or contact con
dition indicate a need (or replacement.
When the arc chutes are removed,
the contact braids, coil protectors,
and other parts subject to arcing
should be checked for possible clean
ing or replacement. Do not grease
the arcing contacts under any cir

haul and inspection is more detailed
and will require disassembly of mech
anism and breaker operating parts.
2. Tlie trip roller and trip shaft beartngs
In the operating mechanism should be

disassembled, cleaned and repacked

with G.E. Lubricant DS0H15 as des
cribed under "Lubrication".

Check

all

mechanism

adjustments, latches, stops, auxi
liary devices, etc., in accordance
with
INSTALLATION, ADJUST
MENTS. Examine latch and roller
surfaces for corrosion.

3. Damaged trip coil.
REMEDY: Replace damaged coil.
4. Blown fuse in trip circuit.
REMEDY: Replace blown fuse after
determining cause cf 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 me
chanism.

2. Mechanism binding or sticking
caused by being out of adjustment.
REMEDY:

Check

all mechanism

adjustments, latches, stops, auxi
liary devices, etc., in accordance
with

INSTALLATION,

MENTS.

ADJUST

Examine latch and roller

surfaces for corrosion.

3. The cw> bearing at the hinge point of
the contact blade should be disas

sembled, inspected, cleaned and relubricated with G.E. contact lubricant

D50H47. It is not necessary to grease
the self-Iubrlcating contact ring at the
hinge point between the contact blade
and bushing. The contact ring should

be inspect^ 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 ol the contact
and contact support cleaned and lub
ricated with G.E. lubricant P50H47.

3. Control device sticking or not op
erating properly.
REMEDY: Check and adjiist con
trol device, or replace.

4. Damaged or dirty contacts In con
trol circuit. Including control de
vice.

REMEDY: Recondition or replace
contacts.

5. Damaged control device colt.
REMEDY: Replace damaged colL
6. Damaged closing coil.

REMEDY: Replace damaged coil.

5. The breaker and operating mechan
ism should be serviced as described

for every 2,000 operations and prop
erly adjusted before being put back

switch.

into service.

REMEDY: Replace defective switch.

TROUBLE SHOOTING

Failure of a breaker to operate prop
erly will generally fall within three general
classes; (allure to trip, failure to close or

latch closed, and overheating. The follow
ing is a brief outline showing particular

8. Blown fuse Ir. closing circuit. REMEDY: Replace blown fuse after
determining cause of failure.

9. Faulty connections in closing cir\
cult.

REMEDY: Repair broken or loose

Magne-bbist Circuit Breaker Type AM-13.8-3 GEH-2004
I *

7. Arc Chute Uounting

1. Rear Buthinit

2.,Su()iiortini Bolt

Bracket

4. Movable Arcing Contact
S> Assrably Bolts

8. Lover Mounting Support
9. Lover Supporting Bolt
10. Upper Horixontal Borrier

6. Side Brace for Arc Quite

11. Lower Horixontal Barrier

3. Upper Uounting Support

Fig. IS

3.
3.
4.
5.
6.
7.
8.
9.

Asse^ly Bolts
Upper Pole Pieces
Lover Pole Pieces
Bear Brace

AssesAly Bolt
Assesbly Bolt
Lover Brace

Asseobly Bolts

Fig. 16

Reeoval of Arc Chute Asseobly

wires and see that all binding screws

are tight.

of adequate rating for present or
future load, or re-arrange circuits

REMEDY: Install larger wires and
Improve electrical contact at con-

necUons.
lA

J.1. Insufficient control voltage caused

by poor regulation (a-c control).

«o

REMEDY: ' Install larger control

be sure It Is delivering adequate
d-c supply. *

transformer.

Check rectifier to

Primary comiections of inadequate
capacity.
REMEDY:
Increase size or num
ber of conductors or remove excess
current.

1. Poor condition of contacts due to

lack of attention after severe duty
or too frequent operation.

-j,

tiw

REMEDY: Tighten.

adjusted.
~
REMEDY: Check all adjustments in

accordance with INSTALLATION,
ADJUSTMENTS.

3. Breaker kept closed or open for
iy>v., '

place, or arrange some means of
cooling.
REPAIR AND REPLACEMENT

detail the proper method of removing vari
ous parts of the breaker In order to make
any necessary repairs. This section in

2. Contacts not properly aligned or

too long a period.
REMEDY: Operate breaker more
often to wipe contacts clean. Re-

place contacts if necessary.

4. Overloading.

REMEDY: Replace breaker with one

Arc Chute Asseabl jr Cospl ete

bolts (2), Fig. 15, and the one lower suy! •
porting bolt (9), Fig. 15, using a 3, 4"
assembly about 1/2" and sliding it toward
the rear of the breaker, it can be removed.
This operation may be accomplished with
the aid of an arc chute lifter.

ceed as follows:

1. Remove the assembly bolts (2, 7,
9, 10. 12, and 15), Fig. 16.

tacts should be reconditioned very
necessary).

Assesbly Bolts
Lover Uounting Support
Assesbly Bolts
Assesbly Bolts

nectors.

The following information covers in

carefully and only when absolutely

15.
16.
17.
18.

To disassemble the arc chute after it

REMEDY: Recondition or replace

burned and pitted contacts.. (Con-

14. Side Brace

has been removed from the breaker, pro
6; Loose connections or terminal con

7. Ambient temperature too high.
OVERHEATING

AssexbJy Bolts •
Assembly Bolts
Assesbly Bolts
Upper Mounting Support

wrench. By raising the complete arc chute

so as to remove excess load.

10. Insufficient control voltage caused
by excessive drop in leads.

10.
11.
12.
13.

cludes only those repairs that can bu made
at the installation on parts of the breakers
that are most subject to damage or wear.
IMPORTANT:

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 ADJUSTMENTS and FINAL INSPECTION.
ARC CHUTE - TO INSPECT OR REPLACE
BLOWOUT COILS

To remove an arc chute, first open the
breaker and remove the box barrier (2),

Fig. 13.

Loosen the two upper supporting

2. Remove the side brace (14), the
rear brace (5), the upper pole pieces

(3), and the lower pole pieces (4),
Fig. 16.

3. To remove the upper mounting sup
port (13), Fig. 16, remove the as
sembly bolts (1 <[ 11), Fig. 16, and
the connection bolt (2), Vig. 18.
4. Remove the assembly bolts (18) to
remove the lower brace (8), Fig. 16.

5. Remove the lower mounting support
(16) by removing the assembly bolts
(17), Fig. 16, and the connection
nut (8), Fig. 18.
6. At this point, the fiber side shields
(5), Fig. 18, and the upper arc
runner assembly (3) can be re
moved.

7. Further disassembly of both t>
upper and low arc runner assem

blies can be done by removing the
13

GCH-2004 Magne-blast Circuit Breaker Type AM-13.8-3
I

r^.'7'?.-v=
'•.V-'" ' ~

1. Upper UountiriR Support
2. Connection Bolt

t. upper Arc Eunner Spacers

3. Upper Arc Bimner Assecbly
3. SloTOUt Core
4. SloTCUt Gail

5- Upper Arc Runner

3. Upper Arc fejnner Assembly

9. Lower Arc Eunner Asseebly
10. Lower-Arc Runner Spacers
11. Lower Coll Connection

6. leow^r Arc Runner Assembly
7a Lo«cr Coil Connection

bolts (not illustrated) as shown in
Fig. n.

8. The arc chute sides (6), Fig. 17,
can be separated by removal oi the
-• assembly bolt (6), Fig. 16.
Reassemble the arc chute In the re

verse order.

The following items should

be noted during reassembly:
chute sides before bolting together.

2. Check to insure that electrical con
nections to the blowout coils
tight.

remove snap rings and washers next
to bearing on Icit side.
, ,e..
7. Using a brass rod approximately 15

2. Slide the arc chute forward and lilt

bearing out, taking the right one out
lirst using the opening In the lelt side

(7) as shown in Fig. IS.

it slightly to engage the supporting

bolts (2), Fig. 15, in the slots ol the
upper mounting "support(3).

are

3. When reassembling the arc runner

assemblies, check that the spacers

(1 and 10), Fig. 17. are correcUy
installed.

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 in

sulation (7). Fig. 17, and the arc
chute side (e) is a minimum.

5. Make cerUIn that the electrical
connections (2 and 8), Fig. 18, are
tighU
To reassemble the arc chute to the

breaker, proceed as follows:
1. Rest the lower mounting support.

Front View - Arc Chute Assctibly

(8) on the arc chute mountingbracket

long and 3/8" diameter, drive each
ol meclianism Iramc and the lelt one

out Irom the opening made Irom the

3. Tighten the supporting bolts (2 and

removal ol the right hand bearinj^

both the electrical and mechanical

bearing, brass rodas mentionedabove

9), Fig. 15. These bolts serve as

connections between the bushing and

1. Equally space the fins ol the arc

Fig. 18

Are Chute Aasesbly with Sides Recoved

vArious screws and 1/4" assembly

NOTE: When removing the lelt hand

may have to be bent in order to clear

latch.

8. To reassemble, reverse the above

4. Check that the movable arcing con

tact (4), Fig. 15, passes through
the slot in the upper arc runner

(6) without touching.

TRIP SHAFT BALL BEARINGS

Procedure except to drive bearings

ack in the mechanism Irame, a pipe
should be used so as not to damage

bearing surlace.
NOTE: II latch is to be replaced, the

first seven steps as listed above
should be followed. Also remove the

1. Remove mechanism cover.

set screw holding the latch on shalt

2. Remove mounting bolts lor control

frame to slop movement, and drive

device. Fig. 1, Part 7, letting control
device hang Iree.

Do not remove

firing.

3. Remove the trip coil Irame mounting

bolts. Fig. 24, Part 2, letting Ira me
hang Iree. Also, remove trip coil
leads Irom terminal boards. Fig. 24,
Part 4.

4. Remove the trip coll and plunger
. bracket irom trip, shalt using snap

ring pliers on ring holding trip coii

plunger assembly.
5. Remove switch tar, Fig. 23, Part 5,

Irom latch shalt and snap ring and

washers near bearing.

6. Remove stop bar. Fig. 31, View A,

Part 282, for manual trip rod. Also,

then place block between latch and
Shalt out ol latch. When replacing,
make sure spring is in proper place
and one hall turn has been made to

wind spring. .Also, make sure latch
is in place on stop bar roller before

bearings and shalt are reassembled.

TRIP LATCH ROLLER BEARING
1. Remove mechanism cover.

2. Remove moimting bolts on control

device. Fig. 1, Part 7; letting control
device hang free.
wiring.

Do not remove .

3. Place block between manual trip rou

Fig. 1, Part 6, and stop bar on trip

Magne-btast Ctrcait Breaker Type AM-13.8-3

7.Flexible Braid
8*Connection Bolt

for Arc Chute
3.Bolts for Contact

Support
4.Contact Support
5.Bolt for Flexible

9.Stud -for Uountins
Arcing Fingers

10.Stationary Arcing

Contoct Assetably

-1. Spring Guide
2» Handle for Spring
Coiepressor
3. Spring Cotnpressor
4. Spring Retainer

6.Spring

7.Contact Sitpport
8.Stop Plate

9. Stationary* Prisory
Contact Fingers

5^ Assembly Bolt for
Spring Retainer

Contact

8.AsseBd»ly Bolts
9.Connection Bar

5.yovoble Primary

10«Piston Assesbly

Contacts

Rear Buahins Assembly

Shalt. This holds trip shaft in trip
position and allo%-s trip llnl-.agc to be
free.

Working through hole on left hand side

of mechanism, remove snap ring and
washer from trip rollerpln, Farf 289,
Fig. 31, .View C, using snap ring
pliers.
Slide trip rollerpin. Part 289, Fig. 31,
Just enough to the right to allcrw room

to hook snap ring pliers on ring on
other end of pin. Compress pliers to
free snap ring and pry the pin to the

left with screwdriver to complete the
3

6.Assembly Bolts
7.Movable Arcing

Contacts

3. Cup Bearing
4.Contact Am

Braid

Fio. 19

1.Contact brings
2.Stationary Primary

removal of snap rings.
Trip roller bearing can now be re
moved for lubrication (see section on
LUBRICATION). Particular attention
should be paid to the location of
washers and spacers.
To reassemble, reverse the above
procedures.

Fig* 20 Method of Installing Prir^ary Con
tact Springs Using a Spring Compressor
B. Stationary Primary Contacts (9), Fig. 20

1. Compress the contact spring (6).

2. Removesprmgandspringguide (1).
3. 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

To . replace the Stationary Primary
Contacts;

thin coating of D50H28

grease on the hinged edge of the
finger (9) then place it on the con
tact support (7) so that it is retained
by stop plate (8).
2. Open spring compressor (3) and
assemble spring guide, spring and
spring compression (Fig. 20A).

3. "^rn handle (2) In clockwise direc
tion to

compress contact spring

(Fig. 18B).
Open the breaker and remove the box
barrier and arc chutes as previously de
scribed. To remove the contacts, proceed

vent the spring from slipping out of
the compressor.

4; Place washer (hot shown) on guide
on top of spring, place top of wide
into hole in spring retainer (4) and
the round end of spring guide in
cut-out in primary finger (Fig.ZOC).

as follows:

A. Stationary Arcing Contacts (10), Fig. 19

5. Hold spring' assembly firmly in
place and remove spring compres

1. Disconnect the contact braids from

contact fingers by removing two
bolts (8), Fig. 19.
Orasp the lower end of the contact

finfers with pliers and pull contact
assembly downward to remove from
stud assembly.

Hold spring firmly in

yoke on spring compressor to pre

CONTACTS

sor.

C. Movable Arcing Contact (7), Fig. 21
1. Remove the assembly bolts (8).
2.

Reassemble in reverse order.

D. Movable Primary Contacts (5), Fig. 21
(1200 Amp. Breaker)

To disassemble braids from stud

assembly, remove one bolt (5).

Reraval of Contacts

(2000 Amp. Breaker)
1. Remove the nuts from'"assembly,
bolts (6).
<
2. Remove the connection bar (9).\

3. Remove Uie cup bearing (3).
4. Spread the contact arms (4) and
remove the primary contacts (5).
5. Reassemble in the reverse order.

a time.

1. Apply a

Fig* 2i

To disassemble stud assembly from
contact support, remove two bolts
(6).

1. Remove the nuts from assembly
bolts (6).
2. Remove the primary contacts and
spacers (not illustrated).

Reassemble in the reverse order.

3. Reassemble in reverse order.

E. Contact Blade Assembly (4,5,7) Fig. 21
1. Remove the connection bar (9).
2. Remove the cup bearing (3) and the
pin (2), 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 connec
tion bar (9), Fig. 21.

F. After disassembly and reassembly of
any contacts, check all contact adjust
ments as described under INSTALLA

TION, ADJUSTMENTS.
BUSHINGS
IMPORTANT:

DO NOT REMOVE ALL

SDC BUSHlNfSATONCE. The bushings have
been carefully aligned with the breaker

frame, during assembly at the factory, and
it is important that this alignment be main
tained to facilitate Installation of the break
er in the metal-clad unit.

It is therefore

recommended that the bushings be removed
and reassembled one at a time. Also, be

fore removing any one bushing, measure
the distance from that particular bushing to
adjacent bushings in both directions, so
that it may be reinstalled in the same
location.

It is also possible to remove and re-'.
assemble three bushings at one time. If
IS

GEH-2004 Magne-blast Circuit Breaker Type AM-13.8-3

1. Soleroici Pot
2. Tersinoi Board

Cleats
4. Hot ton plate

_:! I

5* Control Device Trip
Plunger Bod

6. Qosing Areiature
7* Stop Nuts

'2.

B. Front Stud Nuts

9. Plunger Guide

10. Qosing Coil Leads

2. Opening Spring Unit
3. Pivot Pin

4. Trip Coil Mounting Frene
5. Soitch Bar

6. Trip Ceil Plunger Bracket

Fij. 22

jis Is preferred, alisnment of the bushhgs may
accomplished by placing the
oreaker In a de-energized spare metal-clad
unit before lightening the bushing mounting
bolts.

Fig. 23

Closing Solenoid Assesbljr

This must be done before the arc

chutes zre reinstalled.

To replace the bushing, proceed as
follows:

Rear Bushing

1. 'Open the breaker and remove the
box barrier and arc chutes as al

2. Remove the upper and lower hori
zontal barriers (10 and 11), Fig. 15.
3. Remove the connection bar (9),

Fig. 21, and cup bearing (3).

Opening Soring Asseably

4. Loosen the four nuts under the bot

tom plate (4) approximately 1/2".
Support the bottom plate with a
rope sling or hoist and remove the

two rear nuts.

4. Remove the four bolts atthe mount

ing flange of the front bushipg being
removed, and lower the bushing.

5. Remove the nuts 18) at the top of
the front studs. This permits the

5. "Vben reassembling, first mount the
bushing and assemble the cup bear

bottom plate, closing coil, solenoid
pot (1) and control device plunger
guide (9) to be removed.

ing (3) and contact arm (4\ Fig.
21.

TTie contact surfaces at the

hinge point of the contact blade and

ready described.
2. Remove the upper and lower hori
zontal barriers (10 and 11), Fig. IS.

bushing should have a thin coating
of O50H28 grease.

3. Remove the lour bolts (12) at the

6. Check ail contact adjustments as

mounting flange of the rear bushing

outlined under

being removed and lower the bushing

adjustments.

iNSTALLATION,

To reassemble, first place the clos
ing coil and spacers on the bottom
plate (4). Raise into position, in
serting the control device plunger
guide (9) and compressing Uiepiston
ring on the uppr pole piece.

' assembly.

4. Referring to Fig. 20, disassemble
the primary contact- springs (6) as
previously described.

5. Disassemble the spring retainer (4)
by removing mounting bolts (5).
6. Referring to Fig. 19, disassemble
the contact support (4) and^arc
chute mounting bracket (2) by re

CLOSING COIL

replace the solenoid pot (1) and

The closing coil is contained within
the solenoid pot (1), Fig. 22. To remove

8. Tighten the lour nuts under the

moving two Imlts (3).

arc chute properly on the breaker.
The longest projection of the brack
et should be toward the lower end

of the bushing.

bottom plate taking special pre

1. Open the breaker.

2. Remove the bvo closing coil leads
(10). Remove the terminal board
(2) from the solenoid pot and let it

hand by the wires, ^so, remove
the wire cleat band (3).

.Front Bushing

1. Open the breaker and remove the
box barrier and arc chutes as al

ready described.
16

two front studs and nuts (8).

the closing coil, proceed as follows:

7. Reassemble in the reverse order.

The arc chute*mounting bracket (2)
is not symmetrical and must be
assembled correctly to orient the

7. Tilt the bottom plate downward and

3. Remove the stop nuts (7 and 12)on guide studs (II), lower the arma
ture plate (6) and control device
trip plunger (5).

caution to center tJfie closing coil

around the pole piece. If the clos
ing 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

mecnanism adjust

ments as explained under INSTAL
LATION, ADJUSTMENTS.

Magne-blast Circuit Breaker Type AM-13.8-3
\TRIP COIL

' To replace the potential trip coil <3),
Fig. 24, proceed as follows:
rn\
I -fj,

1. Open the breaker and remove the

opening spring unit (2), Ftp;. 23,

by removing the pivot pins (1 and

GEH-2004

INTERLOCK SWITCH
To remove the interlock switch

' Fig. 6, remove the two mounting screws ai
disconnect the lead wires. Reassemble in
the reverse order and check the switch ad

justments as explained under INSTALLA
TION, ADJUSTMENTS.
LATCH CHECKING SWITCH

To remove the latch checking switch

2. Disconnect the two trip coil lead
wires (4), Fig. 24.

h
fV

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

Fig. 24

3. Trip Coil
4. Trip Coil Leads

Potential Trip Coil

two mounting screws anddisconnect the lead
wires. Reassemble in the reverse order and

check the switch adjustments as e.\piained
under INSTALL.ATION, ADJUST.MENTS.
CUT-OFF SWITCH

4. Remove the trip coil (3).
1. Trip Coil Support
2. UountinR Bolts

(7), Fig. 6, (when furnished), remove the

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

8, remove the two mounting bolts and dis
5. After reassembling (in the reverse
order) check the primary contact
gap adjustment as cxpiained under
INSTALLATION, AD.IUSTMENTS.

connect the lead wires. When reassembling,
check the cut-off switch adjustment as ex
plained under INSTALLATION, ADJUST
MENTS.

xisr

GEH-2004 Magne-blast Circuit Breaker Type AM-13.8-3

RENEWAL PARTS
It Is recommended that sulllclent re

newal parts be carried In stock to enable
the prompt replacement ofany worn, broken,
or damaged parts. A stock of such parts
minimizes service interruptions caused by

When continuous operation is a primary

consideration, more renewal parts should
be carried, the amount depending upon the
severity of the service and the time re
quired 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.

bre^downs, and saves time and expense.

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
MECHANISM.

2. SPECIFY THE QUANTITY. CAT-tLOG 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 NEAREST OFFICE-OF THE GENERAL ELECTRIC COMPANY.

ILLUSTRATION REFERENCE
FIG.

Arc Chute

PAGE

22
32

Control Device for All Mechanisms

Cross-sections - Type AM 13.8-3

Impact Trip Device for All Mechanisms

Interlock Plunger
Maintenance Closing Device

Movable Contact Arm Assembly

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

Rear Bushing Assembly

Secondary Disconnect Device and Mechanism ^rts

Undervoltage Device

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

Magne-blast Circuit Breaker l^e AM-13.8-3

GEH-2004

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

to the tabulation below arc listed the parts of those breakers which are

usially recommended for stock for normal maintenance. Other parts are listed
on the following pages.
FIG.
NO.

Operating Rod Assembly

165

(150, 250, 500
(ISOA, 250A, 500A

Movable Primary Contact

5C0B, 500AB

Contact Finger
Contact Finger
Contact Finger
•» Movable Arcing Contact
Stationary Arcing Contact Assembly

212

(ISO, 250, 500
(150A, 250A, 500A
500B, 500AB

Movable Primary Contact
Movable Primary Contact

213

(150, 250, 500
(150A, 250A, 500A

1200

6591644 P-8

Movable Primary Contact

213

1230

6591644 P-8

Movable Primary Contact

Movable Primary Contact

160

(ISO, 250, 500
(150A, 2S0A, 500A

(Mycalex) Lower Shield

Insulation Plate (Mycalex)

Clamp For Duffer
Closing Coil 125 v d-c or 230 v a-c
Closing Coll 125 v d-c or 230 v a-c

Closing Coil 250 v d-c
Closing Coil 250 v d-c
Closing Coil 110 V d-c
Closing Coil 220 v d-c
Potential Trip CoiM2S v d-c
Potential Trip Coil 250 v d-c
Potential Trip Coil 230 v a-c

370

ALL

6275070 G-1

Potential Trip Coil 24 v d-c

Potential Trip Coil 48 v d-c
Undervoltage Device Coll 125 v d-c
Undervoltage Device Coil 230 v a-c
Undervoltage Device Coil 250 v. d-c
Control Device Coil 125 v d-c

Control Device Coil 250 v d-c

753

ALL

6275017 G-34

Control Device Coll 230 v a-c (intermittent)

Control Device Coil 230 v a-c (cont)

GEH-20(M Magne-blast Circuit Breaker Type AM-I3.8-3

i f
C4

BeS5i35R5™

U^Aft:\v»yrKrreCrtsai;-^ -

Cross Section Type AH-13.8-3

SECTIONS "AA"

CRFqjCP

(2000 AMP)
(1200 AMP)
Fig. 26

Cross Section

Magne-blast Circuit Breaker Type AM-13.8-3
REF.
NO.

Box Barrier Clamp
Arc Chute Support
Arc Chute Clamp

Bushing (Long)
Bushing (Long)

Horizontal Barriers (Lower)
Horizontal Barriers (Lower)
Horizontal Barriers (Upper)

Horizontal Barriers (Upper)

Operating Rod Assembly

ALL

2650160 P-22

Connection Bar

(150, 150A
(250, 250A

ALL

26SC176 G-2

Box Barrier Assembly

(500, 500A
(500B, 500AB

Box Barrier Guide Support

ALL

265C170 P-11

265C170 P-12

Box Barrier Guide Support
Box Barrier Guide Support

Wheel Assembly Complete
Wheel Assembly Complete

Front Wheel & .Caster

Wheel & Spanner Bushing

Mechanism Cover (Std.)

ALL

2580672 G-2

Mechanism Cover (Int.)

(500, 500B

(150A, 250A
(SOOA, 500AB

GEH-2004

A Those Breaker Model List Numbers With "W" SuIIlx.
* As Required.
21

GEH-2004

Magne-blast Circuit Breaker Type AM-13.8-3
153.135.137

102-p'

PARTS REFERENCED IN FIGS. 27A, 273 & 27C FOR AI.L RATINGS

Upper Support
Lower Sujiport
Lower Brace

Upper
Upper
Upper
Upper

Rear Brace (Rijiht)

Side Brece IRight)
Upper Pole Piece

Lower Pole Piece
Lower Pole Piece

Lower Pole Piece
Lower Pole Piece
Core

Core Insulating Tube
Spacer

^acer
Gaeket
Stud

•

1674^'
It!.:''^
163-W

Spiicer
Spacer
Spacer

456AB83 P-1
43GA310 P-l
42XA293 p.78

Spacer

421A208 P-497
265C150 P-15

Coil (Upper) (A .and B)
Coi! (L-jwer) (Dj
Coil (Lower) (E and F)

265C155 C-B

l?7

,-1—^26

Piece
Piece
Piece
Piece

265CI62
265C162
265C162
263C162
2G5C162
265Ci62
265CI62
265C162
265C162
2S3C615
253C6I5
421A208
253C615
456A899

• .L23

DESCRIPTION

Arc Chute Assembly, Complete

234D770
2S4D100
263C150

Runner Assembly
Runner Assembly
3
3

Runner Assembly
Runner Assembly
Spacer

Ru.mer Assembly and Coll Support

^acer

619C488 G-l
456A891 P-210
ClA6eeC583 0-1
265C161 P-17
414A131 P-4

^ Adciillonal Drilling Necessary on 619C438 P-3
AAFurnish Drawings tor Additional Work

^acer

(Mycalex) Lower Shield

^acer
^acer

Magne-blast Circuit Breaker Type AM-13.8-3 GEH-2004

Component Part&
Fig. 28C

Rear Bushing issemtly (Ref. Ko. ISO)

Back View

PARTS REFERENCED IN FIGS. 28A. 28B AND 28C

150
151
151
152
152
152
153
153
154
155
156
158
159
160
160
160

ALL

ALL
ALL
«

SOOB, 500AB
ALL
ALL
ALL
ALL
ALL
ALL
ALL
ALL
•

SOOB, 500AB
ALL
*

181
161
161

162
162
162
163
164
164
164
165
165
165
166
166
166

166A
167
168
168
168
169

SOOB, 500AB
ALL
•

SOOB, SbOAB
ALL
ALL
*

1200
1200
2000
1200
2000
1200
1200
2000
1200
2000
ALL
ALL
ALL
ALL
ALL
1200

1200
2000
1200
1200
2000
1200
1200

2000
ALL
1200
1200
2000
1200
1200
2000
1200
1200
2000
2000
1200
1200
1200
2000

236C790 G-6
236C790 0-7
236C790 G-8
269C841 G-2
265C187 G-5
6592330 P-2
6592331 P-2

6592331 P-2
236C791 P-9
236C791 P-19
236C791 G-3

236C791 G-1
236C790 G-9
414A116 P-4
6445087
414A180
6509787 ?-l
6509787 P-1
236C790 P-22
236C790 P-22
236C790 P-22

Nar. Wash. 1/4-20
Nar. Wash. 1/4-20
Nar. Wash. 1/4-20
175V557
258C6G6
258C6G6
258C666
236C791
236C791
236C791
2580666
2360791
2360791
2360791
2580666
6557243
6557243

P-l
P-I
P-3
P-2
P-8
P-3
P-8
P-5
P-20
P-4
P-3
P-4
P-l
P-2

6557243 P-2
265C151P-25

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

24
24
3

3
3
3
3
6
6
6
3

DESCRIPTION

Rear Bushing Assembly
Rear Bushing Assembly
Rear Bushing Assembly
Rear Bushing
Rear Bushing
ing Retainer

Spring Retainer
Spring Retainer
Support
Support

Arcing Contact Support
Flexible Connectors

Arcing Contact Assembly
Insulating Plate
BuKer

Spring
Spring
Spring

Spring Guide
Spring Guide
Spring Guide
Washer For Spring Guide
Washer For Spring Guide
Wa.sher For Spring Guide
Lork Plate

Contact
ConCict
Contact
Contact
Contact
Contact

Support
Support
Support
Finger
Finger
Finger

Primary Contact Finger Retainer
Primary Contact Finger Retainer

Primary Contact Finger Retainer
Primary Contact Finger Retainer
Spacer

Clamp
Clamp
Clamp
Spring

For Buffer
For Buffer
For Buffer
Baffle

* s ISO, 250, 500, 150A, 250A, SOOA
23

GEH-2004

^lagne-blast Circuit Breaker Type AM-13.8-3
217

211 220213 212 213 212

210

220 211 213 212 213 2:22!9 215 220211

For 2000 Anp. Breakers

Fig. 29C For 1200 Asp.. ISO. 250, SOO.
ISOA. 2S0A, 500A MVA Ratings

For 1200 Anp. SOOB, SCOAB
HVA Ratings

Movable Contact Arr. Assesbly

PARTS REFERENCED IN FIGS. 29A, 29B AND 29C
REF.
NO.

(150, 250, 500
150A, 250A, 500A)

1200

23GC792 G-12

Movable Contact Arm Assembly

210
210
211
212

500B, 500AB

1200
2000
ALL
1200

236C792
236C792
802B743
6591644

3
3
3
3

Movable
Movable
Movable
Movable

1200
2000
1200

6591644 P-7
6591644 P-7
6591644 P-8

6
6
3

Movable Primary Contact
Movable Primary Contact

212
212
213
213
213
214
215
216
217
218
21SA

218A
218A
219
220
221

ALL
ALL

(150, 250, 500
150A, 250A, 500A}
500B, 500AB
ALL

(150, 250, 500
150A, 250A, 500A)
SOOB, 500AB
ALL
ALL
ALL
ALL
ALL
ALL

(150, 250, 500
150A. 250A, SOOA)
SOOB, SOOAB
ALL
ALL
ALL

SOOB, SOOAB

1200

2000
ALL

ALL
2000
ALL
ALL
1200

1200
2000
ALL

ALL
1200

G-14
G-13
G-3
P-7

6591644
6591644
258C666
236C792
258C666
421A248
456A874
456A874

P-8
P-8
P-7
G-15
P-6
P-1
P-3
P-2

6
6
6
3
6
3
3
3

456A874
456A874
414A146
414A146
256C619

P-2
P-2
P-4
P-3
P-2

6
6
12
6
6

Contact Arm Assembly
Contact Arm Assembly
Arcing Contact
Primary Contact

Morable Primary Contact
Movable Primary Contact
Movable Primary Contact
Contact Arm

Tube St Piston Assembly
Contact Arm

Piston Ring
Piston Ring Expander
Piston Ring Equalizer

Piston Ring Equalizer
Piston Ring Equalizer
Flex Nut
Flex Nut

Spacer

i
24

At
a

Magne-blast Circuit Breaker Type AM-13.8-3 GEH-20p4

Present Design
Interlock Plunger

PARTS REFERENCED IN FIGS. 30A, 308 AND 30C FOR ALL RATINGS
REF.
NO.

Plunger Interlock, complete
Plunger for Interlock

'Bracket for interlock

/\ ThU plunger interlock frame is wider than the mechanism frame.

This plunger interlock frame is more narrow than the mechanism frame.
25

GEH-2004

Ktagne-blast Circuit Breaker Type AM-13.8-3
\

(SEE VIEW C)
SEE VIEWAL.

(SEE VIEW C)
SEE VIEW 01

Csoslete Spring Assecbiy

HS-13 ltechanis;n for AK-I3.S-3

307

Magne-bUst Circuit Breaker Type AM-13.8-3

GEH-2004

PARTS REFERENCED IN FIGS. 3U, 31B. ti 31C

6443518
258C608
258C608
215D470

255
256

6551742
258C604
6192382
21SD470
281B711
258C609
6375521
6375521
6375521
6375521
6375521
6375521
236C796
65916S2

257
258
259

260
261
261
261
261
•261
261
262
263

P-1
P-6
P-7
G-54

215D470 G-55
P-8
AB P-1
G-51
G-1
P-1
G-2
G-6
G-1
G-5
G-3
G-4
P-6
P-1

236C795 P-45
236C7S6 P-12

1
1

2B4A
265
266

236C796 P-14
414A109 P-4
236C796 G-2

383A926 AE P-1
258C630 P-7
2S8C630 G-3
2S8C630 P-8
414A109 P-8
258C630 G-1
369A411
369A468
258C630 P-3
25BC630 P-5
258C630 P-4
383A926 AF P-20
258C630 P-9
258C611 P-1

270
271
272
273
274
275

276
277

278
279
280

281
281A
282
283
284
285
286
287
288
289
290
291
292
293
294
296
296
299
301
302
303
304
305
306
307
308
308

258C611 P-2
258C611 P-11
414A111 P-1

421A256
258C60S
215D470
215D470
2580611
414A110
414A112

P-1
P-4
G-53
G-52
P-3
P-1
P-1

1
1
1

1
1
1
1
1
1
1
1
1
1
1
1
1
1

619C478 P-19

Spring
Spring Clip
Veeder Counler
Link

Indicaior Assembly
Prop

Closing Coil 125 v d-c or 230 v a-c 500 MVA
Closing
Closing
Closing
Closing
Closing

Coll
Coll
Coil
Coil
Coil

125 V d-c or 230 v a-c 150 & 250 MVA
(250 v d-c) 500 MVA
(250 v d-c) 150 & 250 MVA
(220 v a-c) 500B MVA
(110 V a-c) 500B MVA

Piston Ring AM 13.8-150A, 5C0B, 500AB
250A, 500, 500A
Piston Ring AN! 13.8-150, 250
Piston Ring A.M 13.8-150, 250
Pole Piece AM 13.8-150A, 500B, 500AB
250A, 500, 500A
Pole Piece AM 13.8-150, 250

Guide for Pole Piece AM 13.8-150A, 500B, 500AB
250A, 500, 500A
Guide for Pole Piece AM 13.8-150, 250
Washer
Arm Pbis
Stud
Pin
Clevis
Plate
Rod
Buffer

Complete Spring Assembly
Inner ^ring

Outer ^ring
Spring Retainer
Retaining Plate

Spring Base
Pin
Bracket

Trip Shaft (Standard)

Trip Shaft (interchangeable)

Stop Bar
Trip Shaft Bearing
Spring
Crank
Roller
Link-

1
1
1

215D470.P-18
6509799 •
414A110 P-3
6477097
258C609 P-8
104A2474 P-1
421A210 P-1
25BC608 P-3
258C611 P-5
258C609 P-9
421A209 P-101
258Cf)09 P-6
383A926AE P-39
421A208 F-143
619C478 P-20

Shalt
Crank
Latch
Crank
Link

Plunger

6591632 P-1
6591632 P-2
236C795 P-4

263
263A

DESCRIPTION

Prop Pin
Pin

Trip Roller Bearing
^acer

^ring
1
1
1

Prop ^ring
Trip Roller Pin
Pin

^acer
Pin (Center Phase)
Pin (End Phases)

^•--

GEH-2004

Ntagne-blast Circuit Breaker Type AM-13.8-3

§
:t

361 360 253 355 359 363 356

S^irS^^ajti .dij ^-.>-

I4S-I3 Mechanism for Type AN I3.S-3 Breaker

PARTS REFEREKCED IN FIGS. 32A, 32B AND 32C FOR ALL RATINGS

REF. NO.

350 .
35X
352
353
354

356
358
359
360

361
362
363
364
385
366
367

368
369
370
370
370
370
370
371
26

CAT. NO. TYPE

AM 13.8 (MVA)-3
258C604
25BC604
236C795
174V394
6445059
415A489
456A876
236C788
414A190
236C788

G-3
P-2
P-40
P-1
G-1
P-4
P-6

P-3
2S8C601 G-3
25BC601 P-15
236C788 P-8

236C788 P-7
258C601 P-16

236C788 P-30
456A866 P-1
456A86G P-1
6174582 G-1
6174582 G-2
6174582 G-14
6275070 G-1
6275070 G-2
21SD470G-5

NO. PER
MECHANISM

DESCRIPTION

lilanual Trip Rod
Manual Trip Rod Support

Insulating Tube
Auxiliary Switch
Spacer
Interlock Prop Shaft
^ring
Interlock Prop

Bearing Bracket

Shaft
LirJc
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 (230 v a-c)
Potential Trip Coil ( 24 v d-c)
Potential Trip Coil { 48 v d-c)
Potential Trip Linkage

Masne'^blast Circuit Breaker Type AM-13.8-3 GEH-2004

Fig. 36 LV^icrvoUege Cevice (Kef. 617)

Partial Viex of HS-13 Hechanisn with Current IriP

PARTS REFERENCED MFIGS. 35 AND 36 FOR ALL RATD.CS
r
REF.NO.

CAT. NO. FOR TYPE
aM-13.8-(MVA)-3

607640) P-307
6477427 AA P-S

9915617 AA
I75V574
369A443
6551726
173V578
6076401 P-309

Bracket

Ball Bearing
Pin

U^er^'cliage Device Complete
Stop for d-c only

Spring for d-c only
^ring for a-c only
Pin for d-c only
Pin for a-c ouiy
Pin

n5V562 P-l
38AA330 G-1
^
6477414 AC P-20

2|t
III

2|5
661
662

663
663
Iti

n5V576
374A246 P-l
6558711 P-1
6558723 C-1
6509798

6275017 0-19
6275017 0-33
6275017 O-20

Bracket

Shim for d-c only

Link Arm Assembly for d-e only
Stud

Coupling

Trip Arm
Spring

Coil (125 V d-c)
Coll (230 V a-c)

Coil (250 Vd-c)

v:'!:c^-;r55Icc-TWa.r?-"Sii5r7

M:igne-blast Circuit Breaker Type AM-13.8-3

PARTS REFERENCED IN FIG. 37 FOR ALL RATINGS
REF.
NO.

702
703
704
705
706
709
710
711
713
715
716
717
718
719
720
721
722
723
725
726
727
728
729
730
731
732
734
735
736
737
738
738
• 739

CAT. NO. FOR TYPE

AM-13.8-(MVA)-3
6594553
6591817
6591388
6076403
6477425
6076403
6592554
6557106
6558791

AA
P-1
P-19
P-315
BA P-3
P-311
G-l
P-1
G-l

6509706
6443516
6557105 P-1
6558746 P-1

6558747 P-l
6076401 P-315
6477401 AA P-3
6509794
174V378
174V373
6443666

295B227 G-3
6592505 AA
6558752 G-l
6553751 P-1
6049320

6557068 P-9
6076401 P-385
2236575
4905058
6443667
6174509
6174599
456A334

NO. PER
MECHANISM

DESCRIPTION

Impact Trip Device Complete
Lever

Locking Plate
Pin
Roller
Pin
Crank

Adjusting Screw
Eyebolt Assembly
Spring
Bracket

Spacer
Bracket

Trip Arm
Pin

Spacer
Spring
Rod

Coupling
Bracket
Switc.'i

Frame Assembly
Core Assembly
Angle
Felt Washer
Pin
Pin
Guide

G-4

Coil Frame

G-2
G-6
P-1

Coil for Current Trip 3 Amp a-c
Coil for C.apacilor Trip 230 v a-c

Bracket

Rubber Guard

* Not Shown
31

GEH-2004 Magjiic-blast Circuit Breaker Type AM-13.8-3

Fig. 38 • Control Device for all Mechanises (Ref. 750)

PARl'3 REFERENCED IN FIG. 38 FOR ALL RATINGS
CAT. NO. FOR TYPE

REF. NO.

AM 13.8 (MVA)-3
750
750
750
750
751
752
753
753
753
753
754
755

403A225
403A224
6373988
403A224
295B227
293B227

756
757

6591411 G-1
6591450 Prl
6412255 P-1
6412251 P-1
6591440 G-1
6592161 P-1
6592162 P-1

758
759
760
761
762
763
764
765
766
767
767
768
*769

NO. PER

Control Device, 123 Volt, d-c

G-1
G-4
G-6
G-3
G-2
G-1

Control Device. 230 Volt, a-c (continuous)
Control Device, 250 Volt, d-c
Control Device, 230 Volt, a-c

Auxiliarv Su itch, top or b;ick

Auxiliary Switch, top, 230 Volt, a-c only
Coil, 125 Volt, d-c

6275017 G-19
6275017 G-33
6275017 G-20
6275017 G-34
6591455 P-1
6442392 P-1

6477041
6591412
6591404
6272844
365A458
6370699
6477063
456A812

P-1
G-1
G-1

DESCRIPTION

MECHANISM

Coil, 230 Volt, a-c (continuous)
Coil, 250 Volt, d-c

Coll, 230 Volt, a-c (intermittent)

2
2
2
2
2
2
1
2
2
2
2
2

Support for Contact Tip
Insulation

Support lor Stationary Contact
Core
Blowout Coil

Support for Coil
Connector

Support for Movable Contact
Shield

Spring
Movable Contact

Arc Chute Assembly
Spring

Spring (a-c Int. & d-c)
Spring (a-c Conl.)
Spring
G-1

Hardware for Mounting Control Device

* Not Sbown

12.S8

GENERAL ElECTRIC COMPANY, PHIIADEIPHIA, PA,

INSTRUCTIONS AND
RECOMMENDED PARTS
FOR

GEI-77055E

SUPEHSEOfS G€l-7705Sb

MAINTENANCE
EDWARD LWALENGA
515 45th ST.

MUNSTER, IN46321

GESupply

(219)922-4211
(TO8)709-<»87
FAX: 219-922-4225

MAGIME-BLAST CIRCUIT BREAKER
Types
AM-13,8-150-4
AM-13.8-150-4ML

AM-13.8-250-4, 6S, 6U
AM-13.8-250-4ML

AM-13.8-500-4, 6S, 6U
AM-13.8-500-4ML
AM-13.8-500-4V

With MS-13 & ML-11 Mechanisms

Contents:
INTRODUCTION

, 3

RCCEIVING, HANDLING AND STORAGE . . . 3

INSTALLATION

DESCRIPTION OP OPERATION

ADJUSTMENTS

GENERAL MAINTENANCE . . . . . . . . . . .
RENEWAL PARTS

15
30

SWITCHGEAR PRODUCTS DEPAHTMEIMT

GENERAL^ELECTRIC
PHILADELPHIA, PA.

MAQNE-BLAST CIRCUIT BREAKER
AM-13.8-150 ( A) -4
^

AM-13.8-250 { A )-4, -6S, -6U

AM-13.8-500 ( A )-4, -4V,.-6S, - 6U

A Letter designation A, B, H, and Rused immediately foUowing MVA rating to indicate basic design features
INSTRUCTION BOOK GEI-50I43) SUPPLEMENTS THIS BOOK FOR BREAKERS WITH ML-11 STORED
ENERGY OPERATING MECHANISM (INDICATED BY ML SUBSCRIPT IN TYPE DESIGNATION).
INTRODUCTION

The Magne-blast breaker is the removable and
interchangeable interrupting element used in metalclad switchgear to provide reliable control and
protection of electrical apparatus and power
systems.

its voltage, current, and internipting 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.

The AM-13.8 Magne-blast Breaker is available
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
particular breaker. The nameplate also describes
the control power requirements for that breaker.
The application of a breaker must be such that

PROPER INSTALLATION AND MAINTENANCE
ARE NECESSARY TO INSURE CONTINUED SAT
ISFACTORY OPERATION OF THE BREAKER.

The following instructions will provide complete
information for placing magne-blast breakers in
service and for maintaining satisfactory opera
tion.

RECEIVING, HANDLING AND STORAGE
against condensation, perferably by storing

Receiving and Handling

it in a warm dry room, since water absorp
tion has an adverse effect on the insulation

Each breaker is carefully inspected and packed

parts. Circuit breakers for outdoor metal-

for ' shipment. 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

clad switchgear should be stored in the

equipment only when power is available
and the heaters are in operation to prevent
condensation.

should be filed immediately with the transportation

company and the nearest General Electric Sales

Office should be notified.

The breaker should be stored in a clean

location, free from corrosive gases or
fumes; particular care should be takep

It is e:qpected that due care will be exercised
during the unpacking and installation of the breaker

to protect the equipment from moisture

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

so that no ^mage 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
coated with grease to prevent rusting.

Storage

It is recommended that the breaker be put into
service immediately in its permanent location.
If this is not possible, the foUowing precautions
must be taken to insure the proper storage of
the breaker:

The breaker shotild be carefuUy protected

If the breaker is stored for any length of

time, it should be inspected periodicaUy to see
that rusting has not started and to insure good
mechanical condition.
Should the breaker be
stored under unfavorable atmospheric conditions,
it should be cleaned and dried out before being

placed in service.

(Cover photo 8021741)
Tlvtaa Instraceiona do not purport to cover all datoila or variations in equipment nor to provide for

ovary possible ccntinyoncy to be met in connection ifitb installation, operation or aMintenonee.

Should

further information be desired or should particular problems arise which are not covered sufficiently for
the purchaser's purposes, the matter should be referred to Che Oeneral Electric Company.
To the extent required the products described herein meet applicable AESI, IEEE and t/EMA standards/
but no such assurance is given with respect to local codes and ordinances because they vary greatly.

GEI-77055 Magne-Blast Circuit Breaker
INSTALLATION
1.

cover and make a visual inspection to as
certain that the

breaker and mechanism is

in satisfactory condition.

Check all beari:^

surfaces of the mechanism for lubrication.

Refer to section on lubrication, page

If the breaker has been stored for a long
period of time, it is recommended that the
insulation

checked

with

standard

Hertz high potential test. Refer to Insulation

Test (Page 18).

18 ,

and Figure 17.

Lubricate the silver portion of the ball contact

Operate the breaker manually using the main
tenance closing device provided with the

portion of

at the top of the breaker bushing and the rear

breaker. Mount the device as shown in Figure 1

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

the ground shoe by applying a

thin film of contact lubricant D50H47.

Refer to raetal-clad instruction book GEH-1802

for instructions on inserting the breaker into
the metal-clad unit.

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 com

pleted.
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 manual trip lever is
operated.
At this time,
also check the
following adjustments:

Arcing contact wipe (Refer to page 7 ).

b. Primary contact wipe (Refer to page 8 ).^
c.
3.

Primary contact gap (Refer to page 10 ).

Connect the test coupler to the circuit breaker

and operate it electrically several times.
Check the control voltage as described under
"CONTROL POWER CHECK" (Page 14 ).
4.

Figure 1. (8022396) Method of Mounting Mainte
nance Operating Device

Closing Armature

Handle

Disconnect the test coupler and replace box

Maintenance Operating Device

barriers.

Release Valve

DESCRIPTION OF OPERATION
The Magne-blast Breaker has two principal
components; the breaker element and the operating

metal-clad imit are made through the coupler

(1) Figure 2.

mechanism:

The breaker element is three similar pole
units, each of which includes the current carrying
parts, main and arcing contacts, interrupter, and

an enclosingbarrier system thatprovides insulation
between poles, or phases and to ground. The
primary connections to the associated metal-clad
switchgear are made through the ball contacts at
the top of the breaker bushings.

The operating mechanism can be either a type
MS-13 solenoid mechanism or a type ML-11
stored energy mechanism. Both mechanisms are

designed to give high speed closing and opening.
All secondary connections from the breaker to

The type ML-11 mechanism will operate on
a-c or d-c voltage as indicated on the breaker
nameplate.
Closing and opening operations are
controlled either electrically from the metal-clad
unit and remote location, or mechanically by
the manual close and trip levers on the breaker.
Refer to GEI-50143 for complete description of

operation and maintenance on the type ML-11

stored energy operating mechanism.

The closing'solenoid of the type MS-13 mechanism operates on d-c voltage only as indicated A

on the breaker nameplate.
For a-c voltage ~
closing, rectifiers mounted in the metal-clad
unit are used to supply the direct current on which

Magne-blast Circuit Breaker GEI-77055
the closing coil operates. Closing operations are

.rffc^controlled electrically from the metal-clad unit
Old

operate on a-c or d-c voltage as indicated on the

breaker nameplate. Opening operations are con
trolled either electrically from the metal-clad
unit and remote location, or mechanically by

lock that trips the mechanism before raising or
lowering of the breaker can be accomplished.
A fork-type lever can be furnished, when required,
to operate an auxiliary switch mounted in the
metal-clad unit.

CLOSING OPERATION OF MS-13
SOLENOID OPERATED BREAKER

the manual trip lever (6) Figure 2 on the breaker.

A positive interlock and interlock switch (7)
Figure 10, are provided between the breaker and
metal-clad unit to prevent raising or lowerii^
of 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 raised or
lowered position.

The closing sequence is initiatedfrom a control
switch mounted 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, Figure 3, which is
mounted on the operating mechanism and controls
the closing operation of the breaker. As the
control device closes, seal-in contacts shunt the

A plunger interlock, Figure 13 can be provided
when required to operate a stationary auxiliary
switch and/or a rod interlock mounted in the
metal-clad unit.

The operating mechanism used on those
breakers designed for MI-6 metal-clad equipment
differ somewhat from those designed for M-36

—3

equipment but its operating principal is the same.

Breakers for MI-6 equipment are identified by
an "A" suffix in the breaker nomenclature thus:
AM-13.8-250A-4 or AM-13.8-500A-6S, In lieu of
the control device mounted on the breaker the
solenoid mechanism is controlled by a relay
scheme located in the metal-clad unit and a
cut-off switch located on the breaker.
Two
seven-terminal secondary couplers are used in-

stead of the single sixteen-terminal coupler. The

positive type interlock between the breaker and

the metal-clad unit is replaced bv atrip type inter-

• I . r

-7

Figure 3 (8030928) Control Device

Figure 2 (8029611) MS-X3 Operating Mechanism
1.
2.

Secondary Coupler
Auxiliary Switch

Control Device
Closing Solenoid

Trip Paddle

Back Auxiliary Switch

GEI-77055 Magne-blast Circuit Breaker

contacts of the closing control switch, permitting

them to open without affecting the overall closing
operation. Once the control device contacts are
picked up, they are electrically held in the closed
position until the breaker closing operation is
completed.
This assures complete closing of
the breaker with only momentary contact of the
closing control switch.
As

the

main

contacts

of the control device

close, the breaker closing coil is energized. This

raises the armature (6) Figure 4 which in turn
lifts the closing roller (4) tiirough plunger (14).
This motion is transmitted through the mechanism
linkage, and rotates the main crank (1), closing

When the solenoid armature is near the end

of its stroke the control device plunger (9) Figure
3 mechanically trips the main control device
contacts, de-energizing the closing coil and allow
ing the armature to return by gravity to its
original position.
The control device plunger
also mechanically trips the seal-in switch, deenergizing 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

As the armature reaches

"pumping" of the breaker will not occur during
a trip-free operation.

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

The operating sequence for those breakers
designed for MI-6 metal-clad equipment is similar

the breaker contacts.

mechanism is trip-free at all times.
During

springs (9 and 10) are compressed in readiness
for an opening operation.
A rubber buffer (5)
above the armature absorbs the energy of the
mechanism as it approaches the end of its stroke.

Main Crank

2.
3.

Trip Latch
Trip Roller

to that described above except tihat a relay mounted
elsewhere in the metal-clad unit replaces the
control device. Also, a out-off switch (Figure 5)
is used to replace the mechanical trip arrange
ment of the

control device.

The cut-off switch

energizes an auxiliary relay to de-energize the
main relay.

evening Spring, Inner
Opening Spring, Outer
Closing Prop Pin
Prop
Closing Coil
Closing Plui^er Rod

T7T7\

Figure 4.(0137A7682) Cross Section of MS-13 Operating Mechanism in the Open Position.

Magne-blast Circiiit Breaker GEI-77055

The breaker can be opened either electrically

by energizing the trip coil (1) Fimre 25 or

manuiily by pushing the trip lever (6) Figure 2.

In each meUiod the trip latch (2) Figure 4 is
rotated off the trip latch roller (3) permitting the
operating mechanism linkage to collapse. The
energy stored in the opening springs is released
to provide the required opening speedforsuccessful
interruption of the circuit. During this operation
the trip coil circuit is de-energized, and upon
completion of the opening operation, the operating

\r>H,

-v- .

mechanism is returned to its normal position,
ready for closing.

As the breaker opens to interrupt a current,
the arc first starts at the arcing contacts (7 & 20)

Figure 6, transfers to the arc runner (4 & 8) and

energizes the blow-out coils (5 & 9). This action
introduces

magnetic field between the pole

pieces (11) of the interrupter that forces the
arc deeper into the arc chute (3). At the time
the arcing contacts part a discharge of air is
expelled through the booster tube (25) across
the arc. This air floV/ assists the arc transfer
and interruption by blowing the arc away from
the contacts and into the arc chute.
As the

magnetic field forces the arc deeper into the
interrupter along the diverging arc runners, the
field is progressively increased by the inser
tion of

Figure 5. (8021970) Cut-off Switch
1.
2.
3.
4.
5.

Cut-off Switch
Switch Roller
Striker
Washers
Lever Arm

each additional blow-out coil into the

circuit.

The arc chute has a series of interleaving

ceramic fins, Figure 19, As the arc is forced
into the interrupter
it is lengthened in the

gradually deepening serpentine path between the

fins so that toe electrical resistance of toe arc

is rapidly increased and its heat is absorbed
by the ceramic material.
The increased re
sistance reduces the magnitude and phase angle
of toe current and at an early current zero
the arc cannot re-establish itself and interruption
occurs.

Trip Free Operation

K toe trip coll circuit is energized while
the breaker is closing, the trip armature will

force the trip latch (2) Figure 4 away from the
trip roller (3) causing the mechanism linkage to

collapse and toe breaker to re-open. The closing
armature (6) completes its closing stroke, the
closing coil is de-energized at toe end of the
stroke and the armature is returned to its original

position by gravity.

ADJUSTMENTS
All adjustments should be checked during
periodic inspections and whenever it becomes
necessary 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
toe box barriers and front cover from the breaker.
DO NOT WORK ON EITHER THE BREAKER

OR THE

MECHANISM WHILE IN THE CLOSED

POSITION UNLESS THE PROP AND TRIP LATCH
HAVE BEEN SECURFLY WIRED OR BLOCKED
TO PREVENT ACCIDENTAL TRIPPING.

Arcing Contact Wipe

Refer to Figure 7. Close toe 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. 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 making this check,

GEI-77055 Magne-blast Circuit Breaker

see that the movable arcing contact (5) passes
-*»«».hetween the probes on the upper arc ninner
vithout touching. On the "-6" design, 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 7,

when the breaker is

closed the stationary primary contacts (1) should
rise from 1/4" to 5/l6". Before checking this
dimension be sure the mechanism is re-set so

Figure 6. (0634D0372) Cross Section of Breaker Pole Unit
1.

Box Barrier Catch

2.
3.

Box Barrier
Arc Chute Side

21.

22.
23.
Upper Arc Runner
14. Upper Horizontal Barrier 24.
Upper Blow-Out Coil
15. Main Operating Crank
25.
Upper Blow-Out Core
16. Upper interrupter Support- 26.
Movable Arcing Contact 17. Spring Retainer
27.

8.
9.

Lower Arc Runner
Lower Blow-Out Coil

4.
5.
6.

Pole Pieces
12. Front Bushing
13. Rear Bushing

11.

10.

Lower Blow-Out Core

18. Lower Horizontal Barrier 28.

19. Operating Rod
29.
20. Stationary Arcing Contact

Stationary Primary Contact
Movable Primary Contact

Movable Contact Arm Assembly
Cup Bearing
Booster Tube and Piston
Front Vertical Barrier
Check Nut
Connection Bar

Booster Cylinder

Magne-blast Circuit Breaker GEI-77055

that the prop pin (11) Figure 4 is resting on

increase it.

loosen the check nut (4) and turn the adjusting

be^een

decrease the primary contact wipe, down will

the breaker is fully closed.

the prop. To obtain the proper contactadjustment,
open the breaker and, referring to Figure 8,
nut (3).

Screwing up on the adjusting nutwm

Tighten the check nut, close the

breaker and recheck the wipe. With the primary

contact wipe correctly adiusted, the clearance

contact arm (6) Figure 7 and the

buffer block (3) should be 1/16* or greater when

Arcing Contact Wipe

Primary Contact Wipe

Figure 7A. (0114C5320) "-4" Contact Structure

Primary Contact Wipe

Arcing Contact Wipe

Figure 7B. (0132C2709) "-6" Contact Structure
Figure 7. Contact Adjustments
1.
2.

Stationary Primary Contacts
Movable Primary Contacts

Buffer Block

Stationary Arcing Contacts

Movable Arcing Contacts

6.
7.

Contact Arm
Throat Baffle

GEI-77055 Magne-blast Circuit Breaker
P-rimary Contact Gat

Prop Clearance

Refer to Figure 8.

With the breaker closed,

vpress the manu^ 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
contacts (8) measured between the closest points,

should be 5-1/8" to 5-9/16". To change this gap,
loosen the check nut (25) Figure 9, and turn the
adjusting nut (26) on stud (9).
Screwing the
adjusting nut down will decrease the primary
contact gap. Tighten the check nut and re-measure

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

Refer to Figure 9.

With the breaker closed

as far as possible with the maintenance 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 deter
mine 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 armature from the
mechanism and remove the two set screws (19).
Remove the closing plunger (17) from the armature

MECHANISM IN

and add or subtract the necessary thickness of

THE CLOSED POSITION, KEEP FINGERS CLEAR

shims (20) to give the required adjustment, then
replace the closing plunger, screwing it down

WHEN

WORKING

ON THE

OF THE LINKAGE, AS ACCIDENTAL TRIPPING
CAN CAUSE SEVERE INJURY.

against the shims. Using a small drill, spot the
closing plunger through toe set screw hole. Re

Trip Latch Wipe

place

Refer to Figure 9. The wipe of the trip latch
(4) on the trip roller (6) should be from 3/16"

to 1/4".

the set screws.

Remount the armature

on the breaker. After reassembly, remount the
maintenance closing device and check the ad
justment.

This can be measured by putting a film

of grease on the latch, closing the breaker part

Closing Plunger Clearance

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 usually all that is required.
If this setting is not correct, look for insufficient
travel of the trip shaft (3).

Refer to Figure 9. With the breaker in toe
open position, toe 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 toe 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 clearance.
Interlock Switch Adjustment

Referring to Figure 10, rotate toe interlock
shaft (4) manually clockwise to release the inter
lock switch arm (6).
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 toe interlock switch

(7), bend the interlock switch arm (6). The roller
and crank on the interlock switch should have

1/32" to 1/16" overtravel after final adjustment.
Control Device Adjustment
BEFORE MANUALLY OPERATING THE CON

TROL DEVICE MAKE CERTAIN THAT ALL CON
TROL POWER TO THE BREAKER HAS BEEN
DISCONNECTED. MANUAL OPERATION OF THE

Figure 8. (8038802) Adjustable Coupling For Making
Primary Contact Wipe Adjustments
1.
2.

Operating Rod
Operating Rod Pin

Adjusting Nut

Check Nut

Stationary Primary Contacts

6.
7.

Yoke
Contact Arm

Movable Primary Contacts

CONTROL DEVICE
CONNECTED WILL

WITH CONTROL POWER
ENERGIZE THE CLOSING

COIL AND PRODUCE A CLOSING OPERATION.
Referring to Figure 3, measure the overtravel

of the two auxiliary switch plimgers.. Manually
operate the control device by pressing the operating
arm

(6)

toe full extent of travel to the rear.

With the device in this position, further depress
the plunger (5) on the top auxiliary switch (4).
The gap between the plunger and operating arm
should be 1/32" or greater. To increase toe

Magne-blast Circuit Breaker GEI-77055

Main Crank

3.
4.
5.

Trip Shaft
Trip Latch
Trip Latch Stop Pin

Trip Roller

7.
8.

Position Indicator
Clevis

9.
10.
11.
12.
13.
14.
15.
16.
17.

777y7r////////777777X

Main Operating Shaft

Adjustable Stud
Closing Pin

Opening Spring Housing
Opening Spring, Inner
Opening Spring, Outer
Closing Roller
Prop
Closing Coil
Closing Plunger

18.
19.
20.

Rubber Buffer
Set Screws
Shims

21.
22.

Closing Armature
Stop Nuts

Figure 9. (0962C0772) Cross Section of MS-13 Mechanism in closed position.
overtravel, loosen the screws (3) 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 (2).

Operate the solenoid armature plate (12)
with the maintenance closing device. The control
device plunger (9) should not travel more than

3/32" from the point where the control device
trips until the prop (15) Figure 9 falls in place.
The plunger should travel a minimum of l/32"
after tripping the control device.

The control

device arm (7)' Figure 3 should have a minimum

of 1/32" overtravel with the plunger fully raised
by the armature plate.

If adjustments are necessary, loosen nut (11)
and raise or lower adjusting screw (10) the
correct amount. Tighten nut after adjusting and
again measure the travel of the control device
plunger.

Cut-Off Switch Adjustnients

(Breakers with "A" Suffix)
Refer to Figure 5. 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
(4) should be added or removed if necessary to
correct adjustment.
AUXILIARY DEVICES

Latch Checking Switch Adjustment

Referring to Figure 11, rotate the trip latch
(4) clockwise by pressing the manual trip button
to open the latch checking switch contacts and to
release the latch checking switch operating arm
(3).
Allow the trip latch to reset slowly and
determine the point at which the contacts make
by using a circuit continuity tester, such as a
light indicator or bell set. The contacts of the
latch checking switch should iust make when the

jap between the trip latch (4) and the stop pin
5) located on the crank (6) is 1/16". The roller
.2) on the latch checking switch should have a
minimum of 1/32" overtravel after final adjustment.
To obtain adjustment of the latch checking
switch (1). bend the latch check switch oper
ating arm (3).
11

GEI-77055 Magne-blast Circuit Breaker

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.

y.
ese*Meie

-J

After checking all the mechanical adjust
ments as outlined above, operate the devices
manually to make certain that they trip and reset
properly.
Plunger Interlock

Refer to Figure 13.

eII

With the breaker in

the close position, the vertical distance "A"
from the top of the interlock bolt (2) to the bottom
of the elevating bar (13) should be 11-7/32" to
11-11/32".

To change this adjustment add or

remove washers (3).
Inspection and Test

Figure 10. (8024689) Interlock Switch and Latch
Checking Switch

1.
2.

Mounting Screw
Latch Checking Switch

3.
4.
5.
6.
7.
8.

Latch Check Switch Arm
Interlock Shaft
Trip Shaft
Interlock Switch Arm
Interlock Switch
Mounting Screw

For ease .in reviewing the adjustments the
following are recapitulated:

Primary contact wipe:

1/4" to 5/16".

Arcing contact wipe: 5/16" or greater

Primary contact gap; 5-1/8" to 5-9/16".

Trip latch wipe:

Prop clearance: 1/32" to 3/32".

Closing plunger clearance: l/l6"to3/16".

gap at primary contacts.

3/16" to 1/4" with

trip latch resting against stop pin.

g. Interlock switchovertravel: l/32"to 1/16".
Auxiliary

Switch

Linkage

Control device switch overfravel: 1/32"
minimum.

(Furnished Special on Breakers with "A" Suffix)
Refer to Figure 12. With the breaker in the
open position, the distance from the center line
of the front bushings (1) to the center of the

Cut-off switch overtravel: 1/32" to 1/16".

Latch checking switch contacts make when
the gap between trip latch and stop pin

switch operating pin (3) should be 12-1/4" as

is 1/16".

shown. To change this setting, loosen the locking
nut (6), remove the pin (4), and turn the clevis
(5). Reassemble and check adjustment.

Impact trip roller wipe: 3/32" to 5/32".

Impact Trip, Current Trip and Undervoltage

Impact trip bolt clearance: 1/32" to 1/16".

Undervoltage

Plunger interlock: 11-7/32" toll-ll/32".

Figure 13 shows the necessary settings that
are to be

nished.

checked when these devices are fur

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 plate (14) stops. In order to trip properly,

Auxiliary switch linkage ("A" breakers

only) 12-1/4".

y-^fje clearance between the trip bolt (11; and the

Check all nuts, washers, bolts, cotter pins,
and terminal connections for tightness.

can be altered by releasing the check nut and
screwing the trip bolt (11) in or out of the reset

Inspect all wiring to make sure that no

rip plate (9) should be 1/32" to 1/16".

arm (8).

This

Magne-blast Circuit Breaker GEI-77055

Figure 11. (0137A6038) Latch Checking Switch
Adjustment

1.
2.
3.
4.
5.

1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.

Latch Checking Switch
Latch Checking Switch Roller
Latch Cheddhg Switch Operating Arm
Trip Latch
Trip Latch Stop Pin

Crank

Trip Roller

Figure 12. (0264B0153) Auxiliary Switch Linkage
1.

Front Disconnect Stud

Plunger Interlock Bolt
Washers

Connecting Rod
Reset Plate
Reset Roller

Main Operating Shalt
Reset Arm

Trip Plate
Spring
Trh? Bolt
Clevis

Elevating Bar

Impact Trip Plate
Trip Latch
Trip Roller
Trip Armature
Trip Lever
Undervoltiue Trip Hammer
Adjusting Rod
Manual Trip Button
Trip Setting Plate
Undervoltage Device

Figure 13 (0634D0336) Adjustments on Current Trto Device, Underroltage Trip Device,

and

Pliuiger Interlock ShownWith The Breaker in The Closed Position

GEI-77055 Magne-blast Circuit Breaker

.4.

. damage has resulted during installation and
test for possible grounds or short circuits.

should be a minimum of 15 feet per second at
rated control voltage. This speed represents the

See that all bearing surfaces of the mechanism

tip on the movable arcing contact is tangent
to the lower surface of the probes on the upper
runner. Proper servicing.and lubrication of the
breaker and its operating mechanism should
maintain these speeds and no adjustment is

have been lubricated.

Refer to the section

on LUBRICATION.

Operate the breaker slowly with the main
tenance 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 positions.

average speed over 3" from the point when the

provided.

Control Power Check

After the breaker has been operated slowly

See that any place where the surface of the
paint has been damaged is repainted imme

several times with the maintenance closing device,

diately.

scribed above, the operating voltages should be
checked at the closing coil and trip coil terminals.
Control power for electrical operation of the

Auxiliary Devices

On breakers that are 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 undervoltage trip device should trip the
breaker when the control voltage drops below 30 to

and the mechanism adjustments checked as de

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:
NOMINAL
VOLTAGE
125v d-c

60% of rated voltage, and it should pick up at
80% of the control voltage or less. An adjust

250v d-c
230v a-c

ment plate is provided on the front of the under-

CLOSING
RANGE

90-130V d-c
180-260v d-c
190-250V a-c

TRIPPING
RANGE

70-140vd-c
140-280vd-c
190-250va-c

voli^e trip device as an aid in obtaining the
desired setting.

^jg^IOTE:
'

When checking the pick-up value of the

mdervoltage device, apply a

voltage equal to

80% of normal control voltage to the undervoltage
device coil.
The device should pick up at this
value.
Do not increase the voltage gradually
on this coil as it will overheat the coU, producing
a false reading, and may damage the coil if
excessive overheating occurs.

The capacitor trip should be C£q)able of trip

NOTE:
When repetitive operating is required
from a direct current source, the closed circuit

115v d-c and 230v d-c at the nominal voltages

of 125v d-c and 250v d-c, respectively.

To check the d-c voltage at the closing
coil terminals, proceed as follows:

ping the breaker as late as 25 seconds after the

If the axixiliary devices do not perform in
accordance with these specifications, a careful
examination should be made for defective parts.
Opening and Closing Speed

The closing speed of the arcing contact should
be 7 to 10 feet per second for the 150 and 250 MVA
breakers and 9 to 13 feet per second for the 500

MVA breakers with rated closed circuit volt^e at

the closing coil 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 probes on the upper arc
/^^unner to the tangent position.
The opening speed of the arcing contact
14

Mechanism with a control device, Figure 3.
Close the breaker by manually operating the
control

control voltage is removed. The ST-230 trip
device is capable of tripping the breaker for a
limited period of time aEter the control voltage
is removed.
See instruction book for ST-230
for necessary checks.

voltage at the closing coil should not exceed •

device.

Hold the contacts in the

closed position and read the d-c voltage at
the closing coil terminals. To de-energize
the circuit, release the control device.

Mechanism with cut-off switch. Figure 5.
Close the breaker by manually operating
the control relay located in the metal-clad
unit. Hold the relay closed and read the d-c

voltage at the closing coil terminals. Re-

lease 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, check the voltage at the source of power
and line drop between the power source and
breaker.

For a-c operation a germanium (color-black-

flanged base) - or a silicon (color-blue, hex base)

rectifier bridge assembly is used, it is mounted

in the metal-clad unit.

These rectifiers are of

the button-type and are hermetically sealed units.

RECTlHim REPBagMCg CHART

Roctlflor Roolator Setting

Cloalng Coll
Owg. Ho.

RECTIFIER REFERENCE CHART

silicon

58.0

0,75X1
—»

COIL
RECTIFIER
AMPS. RESISTOR SETTING

l25nt.75 I75 1.25
1
0.75-^

125^.75 1.75 \25 1
1

Figure 14. (0176V0946) Rectifier Reference Chart

Figure 15. (0137A7676) Rectifier Reference Chart

They have been tested and the associated resistor

the same control power source, are required
to close simutaneously, the closed circuit voltage
at the closing coil of each breaker must f^

properly set at the factory. Unlike copper-oxide
rectifiers 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.
(See Rectifier Reference
Charts, Figure 14 & 15.)
DO NOT MAINTAIN VOLTAGE ON THE CLOS
ING COIL ANY LONGER THAN THE TIME RE

QUIRED TO CLOSE 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 flow.

within the specified limits.

Electrical closi^ or opening is accomplished

by merely 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 the breaker manually by pressing the
manual trip button (6) Figure 2.
NOTE:

This breaker mechanism combination is

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

When two or more breakers, operating from

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

GENERAL MAINTENANCE
General

BREAKER

Safe and dependable service from electrical

apparatus and power systems is contingent upon
reliable performance of power circuit breakers.
To obtain maximum reliability the breaker should

• be
inspected and maintained on aregular schedule.
The breakers are designed in accordance with
applicable standards which require that they 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
eveiTT 2000 operations, or once per year, which
ever comes first. If the breaker is also required
to interrupt fault currents during this period of
time additional maintenance and replacement of
jl^^arts may be necessary.
BEFORE ANY MAINTENANCE WORK IS PER

FORMED, MAKE CERTAIN THAT ALL CONTROL
CIRCUITS ARE DE-ENERGIZED AND THAT THE

IS REMOVED

FROM THE

METAL-

CLAD UNIT. DO NOT WORK ON THE BREAKER
OR MECHANISM WHILE IN THE CLOSED POSI
TION UNLESS THE PROP AND TRIP LATCH
HAVE BEEN SECURELY WIRED OR BLOCKED
TO PREVENT ACCIDENTAL TRIPPING.
PERIODIC INSPECTION

The frequency of the inspection and main
tenance operations required should be determined
by each operating company and will depend on
the application of the breakers and the operating
conditions.

Factors which should be considered

are:
Importance to overall plant or system
operation; number of operations and magnitude

of currents switched by breaker; frequency of
fault interruptions; 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.

Very clean dry operating conditions

with low current switching duty can justify a longer
15

GEI-77055 Magne-blast Circuit Breaker
breakers.

Interrupters

Since there are no moving parts, the interrup

ters of amagne-blastbreakerwillnormally require
little or no inspection unless there is evidence

of damage to the arc chutes sides or contam
ination in the throat area.

either of these

conditions are present the interrupters should
be removed from the breaker and the following

points noted:

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 the ceramic
fins of the arc chute sides or throat pieces.

Heavily contaminated parts should be replaced.
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.

injury due to dropping or accidental striking,
resulting in the actual breaking off of fins,
replacement will be necessary. Small broken

Figure 16. (8034809) Interrupter Removal
1.

If the arc chute has suffered any mechanical

corners on the exhaust end of the arc chute
sides will not interfere with its performance
and can be disregarded.

Arc Chute Lifter Bolt

6.
7.
8.

Grappling Hooks
Upper Horizontal Barriers
Upper Interrupter Support

Lifting Bolt

10.

Lower Horizontal Barriers

11.
12.

Supporting Bolt
Stationarj* Arcing Contacts

13.
14.

Mounting Bolts
Movable Arcing Contact

15.

Arc Chute Brace

16.
17.
18.
19.

Support Bracket
Lower Interrupter Support
Interrupter

The plastisol flexible covering for the pole
pieces (3 Si 8) Figure 18 and the upper
mounting support (12) should be inspected
for breaks

in the insulation.

If there are

holes or breaks in the insulation they should
be repaired or the part replaced.
Interrupter Removal and Replacement

Refer to Figure 16. An arc chute lifter is
normally furnished with the metal-clad switchgear
for use in removing and replacing the interrupters

Lower Supporting Bolt

of the AM-13.8-500 breakers.

When the lifter is

not available an overhead crane or portable hoist

may be used.

The arc chute lifter is assembled

to the top plate of the breaker as shown in the

reference figure using the bolt (5) located between
the front and rear bushings.
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 main
tenance be performed as soon after the interruption
as is practical.

It is also recommended that an

Lower the grappling hooks (6) by turning
the handle (1) until they can be placed over the
lifting bolts (9) on the interrupter.
Turn the
handle

the first 500 operations or six months after being

lift the interrupter.

that should be included in an inspection and
general recommendations on the maintenance of

is necessary to

remove the box barriers.

initial inspection be made of new breakers after

^*4^1 service, whichever comes first.

Before assembling
it

raise

the hooks until they begin to

To remove the interrupter, loosen the two
upper support bolts (11) and the one lower support
bolt (16) using a standard 3/4" wrench. Raise
the assembly approximately 3/8" and gently move

'• I" '^ir iTiiaiiiMiigMBMMBMiigaMWBBBBHBMMM

Magne-blast Circuit Breaker GEI-77055
contacts can be inspected. The stationary arcing
contacts c^n be Inspected only after removing
the interrupter. If the contacts are burned or

it from side to side until both upper and lower

supports are disconnected. More ^e trolley (3)
of me arc chute lifter .towards the rear cd the

breaker and lower the interrupter to a resting
position on the floor. Sufjport the Interrupterfrom
falling over and remove the grappling hooks.

pitted, they ''an be made smooth with a fine
file.

After completing inspection of the contacts,

To reassemble the interrupter to the breaker,
rest the lower interrupter support (18) on the
support bracket (17). Slide the arc chute forward,
lifting it slightly to engage the supporting bolts (11)
in the slots of the upper interrupter support
(8).
On the "-4" design check the spring baffle
(11) Figure 22, to assure that it closes the gap
between the ' upper insulation (17) Figure 18A
and the back surface of the contact support (4)

A carefiil inspection should be made to check
for loose nuts, bolts, and loose or damaged
set screws or other locking devices. All cam,
roller, and latch surfaces should be inspected for

Figure 22.

any

check the contact adjustments as specified under
AEJUSTMENTS.
Mechanism

On the "-6" design .check to assure

that the upper insulation (15) Figure 18B is
properly positioned within the barrier suspended
from the stationary contact support (9) Figure 23.

evidence

damage

excessive wear.

Lubricate the mechanism as outlined below, then,
using
and

certain that the mechanism operates freely through

Tighten the supporting bolts (11 and 16)

Figure 16. These bolts serve as both the electrical
and mechanical connections between the bushings

adjustments as specified under ADJUSTMENTS.

and the arc runners within the interrupter. Check

nections and damaged insulation.

that the movable arcing contact (14) passes be
tween the probes on the upper arc runner (5)

Bushings and Insulation

Check the control wiring for tightness of

con

Figure 19 without touching.
The surface, of the bushings should be kept

clean and unmarred to prevent moisture absorption.
If the insulation surface should become damaged,
it should be sanded and cleaned, and should be

Breaker Contacts

By removing the box barriers the movable and
stationary primary contacts and the movable arcing

Sleeve Bearings - links, trip shaft,

No lubrication required

etc. (Teflon coated bearings')

ALTERNATE LUBRICATION

(REQUIRES DISASSEMBLY)
No lubrication required

Sleeve Bearings - main crank shaft,

Light application of machine Remove bearings or links,

driving pawl lever. (Bronze or cast
iron)

oil SAE 20 or

Contact Arm Hinge Assembly
Cup Bearing
Loose rings between bushing and

No lubrication required

30.

clean per instructions and
apply D50H15 lubricantliberally.

Iwipe clean and apply D50H47.

contact arm

Light application of machine Clean per instructions and repack

Roller and Needle Bearings

oil SAE 20

or SAE 30.

with D50H15 lubricant.

No lubrication required

Ground surfaces such as cams, ratchet

No lubrication required

Ground surfaces such as latches,
rollers, prop, etc.

Wipe clean and apply

D50H15 lubricant

D50H15 lubricant.

Silver plated contacts and primary

teeth, etc. (Surfaces coated withMoS2)

Figure 17. Lubrication Chart

clear

GEI-77055 Magne-blast Circuit Breaker
resin. Allow to dry smooth and hard.

All other insulation parts on the breaker should

- 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

and requires no disassembly. The second method
outlines a lubrication procedure similar to that
performed on the breaker at the factory, and
should be used when a general overhaul of the
breaker is necessary.

General Electric Lubricants

D50H15

and

dryness.

D50H47 are available in 1/4 lb. collapsible tubes.
It is so packaged to insure cleanliness and to

Insiilation Test

prevent oxidation.

When insulation has been repaired or replaced,
or when 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 poten
tial test at 27,000 volts RMS for one minute

will normally indicate whether the breaker is
satisfactory for service. 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.

METHOD OF CLEANING
BEARINGS

Whenever cleaning of bearings is required,

as indicated in the lubrication chart, the following

procedures are recommended.

necessary action must be taken to repair or

outside contaminates, such as dry or hardened
grease. If contaminants are present they should
be removed by immersing the link and bearii^ in
clean petroleum solvent, or similar cleaner, and
using a stiff brush. Do not remove the bearings

by moisture absorption.
Lubrication,

After a number of operations, the

surface will acquire a thin black film.

important that all circuit breakers be properly
,'^jbricated at all times. Most of the bearings and
oiling surfaces utilize a new ^e of dry lubri

cation that will require no maintenance and will
last the life of the equipment. Only few bearings
and surfaces listed in the chart. Figure 17, 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 is essential for the proper operation
of circuit breakers. Also frequent operation of
the breaker causes the lubricant to be forced out

from between the bearing surfaces. A simple
lubrication will often clear up minor disturbances

Do not

remove this film unless there is evidence of

from the links.

In order" to maintain reliable operation, it is

DO NOT USE CARBON TETRA-

CHLORIDE.

The hinge of the primary contact arm (24)
Figure 6, should be disassembled, cleaned, and
lubricated with G-E D50H47 lubricant at general

The main shaft bearings should be removed

cleaned, and lubricated with G-E D50H15 lubricant
at general overhaul periods.
Roller and Needle Bearings

The bearings should be removed from the
mechanism

They should tiien 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 use alcohol (type used

A definite lubrication schedule should be set

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 clean

operation of th^''breaker and local conditions.
It

recommended that lubrication of the

breaker and its operating mechanism be a part of
the periodic inspection and maintenance program,
with not more than a two year period between
lubrications.

It is also recommended that all

ed.

Do not handle the bearings with bare hands

inductive to corrosion. If the bearings are touched,
the contamination can be removed by washing in
alcohol. After the bearings have been thoroughly

cleaned, spin them in clean new light machine

is in good condition and the breaker is operable.

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

The Lubrication Chart, Figure 17, is divided
mto two methods of lubrication. The first method
outlines the maintenance lubrication which should

be performed at the time of periodic maintenance,
18

a
w

as deposits from the skin onto the bearings are

circuit breakers be operated at regular intervals

at least once a year, to insure &e lubrication

a
W

overhaul periods.

which might be mi^aken for more serious trouble.
up taking intoV .cpn^deration the frequency of

The sleeve bearings used throughout the Ull
age utilize Teflon, surfaces and do not require
lubrication.

replace insulation that may have been affected

Sleeve Bearings

After high potential tests are made on organic
insulating materials, these materials should be

inspected for visible leakage current paths, and

all metal parts are greased. The inner races ^
should then be assembled.

NOTE:

If it becomes necessary to clean the

Magne-biast Circuit Breaker GEI-77055

bearings in alcohol (shellac thinner), be sure
the alcohol is perfectly clean, and do not allow

Inspect the condition of the stationary
contact
fingers and movable contact
blocks. Badly pitted or burned contacts

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

should be replaced.
(Note:
Burned
primary contacts indicate the probable
need for arcing contact replacement.)

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. Pre

If the contact surfaces are only roughened
or galled, they should be smoothed with

cautions against the toxic effects of the alcohol

must be 'exercised by wearing rubber gloves and

crocus cloth or draw filed. After contact

by using the alcohol in a well ventilated room;

dressing the primary contacts should be
greased lightly with D50H47.

excessive exposure to the fumes is sometimes

unpleasant to personnel. Washing the bearings
in the light oil, draining and repacking with
lubricant D50H15 should follow immediately.

similar cleaner and a stiff brush.

After

arcing contact wipe is less

for uneven wear and/or damage using
a mirror to inspect the stationary contacts.
Normally it will not be necessary to
remove the interrupters for this 2000
operation servicing unless inadequate wipe

the procedure outlined above using a light machine
oil and G-E lubricant D50H15 before reassembling
the inner race and shaft.

or contact condition indicate a need for

replacement.
If the interrupters are
removed, the contact braids, and other
parts subject to arcing should be checked
for possible cleaning or replacement. Do

MAINTENANCE

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 of tiie applications.
The following schedule is recommended for such

not grease the arcing contacts under any
circumstances.

Every 500 Operations:

The breaker and operating mechanism
should be carefully inspected for loose
nuts, bolts, and loose or damaged set
screws or other locking devices.
All

Remove the box barriers.

cam, latch and roller surfaces should be
inspected for damage or excessive wear.

Wipe all insulating parts clean of smoke
deposit and dust with a clean dry cloth,
including the bushings, and the inside

breakers:

the

than the minimum specified under AD
JUSTMENTS, the contacts should be re
placed. The contacts should be inspected

removing the shaft and inner race the bearing
can be cleaned satisfactorily with petroleum solvent
or a

Arcing Contacts ((7 and 20 Figure 6).
When

Bearings that are pressed into the frame or
other members should not be removed.

Primary Contacts (3 and 10 Figure 23),

The buffer blocks and their retainers on

the bottom of the stationary contact support
should be inspected for possible need of
replacement.

of the box barriers.

All flat parts in the throat area of the
interrupters should be thoroughly cleaned
by using sandpaper. This cleaning should
be performed any time the interrupter
is removed.

The fins on the arc chute

Whenever the interrupter is

blown out before replacing arc chutes.
Throat coolers which are heavily con
taminated should be replaced.

7.
8.

The necessary re

that the breaker contacts can move to the

checked using either the test cabinet or

Every 2000 Operations, or Every Six Months

the test couplers.

Whichever Comes First:

In addition to the servicing done each
500 operations, the following inspection
should be
required.

made

and work done when

After the breaker has been serviced,

fully opened and fully closed positions.
Its electrical operation should then be

under ADJUSTMENTS.

Inspect all wirit^ for tightness of con

it should be operated manually to be
sure there is no binding or friction and

adjustment should be made as described

accordance with instructions

nections and possible damage of insulation.

Check the breaker and mechanism ad
justments as summarized under INSPEC

TION AND TEST.

under LUBRICATION, Page 18 and the
Lubrication Chart Figure 17.

remoyed, loose dust and dirt should be

Lubricate the breaker operating mech
anism

sides and throat cooler fins should not

be cleaned.

The contacts of the control device. Fig
ure 3, should be inspected for wear and
cleaned if necessary.

After Every 10,000 Operations:

In addition to the servicing done each
2000 operations, the interrupters should
be removed from

the breaker and dis-

GEI-77055- Magne-blast Circuit Breaker
tolerances. This overhaul and inspection
is more detailed and will require dis

assembled to permit a detailed inspection
of insulation, blow-out coils, arc runners

assembly

and assemblies which can become con

taminated by arc products.

The blow-out coils should be carefully

operating mechanism should be disas
sembled, cleaned, and repacked with G-E

cracked, shrunk or eroded from arc
action and heat so that the turns of the
coils are not fully insulated from each
connections should be checked for tight

lubricant

(3) Figure 23, should be disassembled

and the silver-plated pivot area of the
contact and contact support cleaned and
lubricated with G-E lubricant D50H47.

replaced when any part of their area has

The breaker and operating mechanism
should be serviced as described for every

2,000 operations and properly adjusted

replace runner when surface coating has

before being put back into service.

been penetrated.
4.

Check the stationary arc contacts to
assure that the arcing contacts are in

good condition and that their connections

This section covers the proper method of

be replaced.

WORK, ALL BREAKER AND MECHANISM AD

PORTANT: UPON COMPLETION OF ANY REPAIR
JUSTMENTS MUST BE CHECKED. Refer to the
section on INSTALLATION, paying particular
attention to ADJUSTMENTS and FINAL INSPEC

be replaced.

TION.

NOTE: Fine cracks may develop in the
fins of the arc chute sides. This is to

ARC CHUTE

as described under INTERRUPTER REMOVAL
AND REPLACEMENT page 16.

corners on the exhaust end of the arc
chute will not interfere with its perform
ance and can also be disregarded.

To disassemble the interrupter after it has
been removed from the breaker, proceed as

The cup bearing and the contact washer
at the hinge point of the contact blade
should be Reassembled, inspected, clean
ed, and relubricated with G-E contact

and its components some small washers, spacers,

The contact washer

should be inspected for wear and replaced
when reduced in thickness to less than

1/32".
When reassembling the cup
bearing, be sure the cotter pin is properly

With the breaker open, remove the box barriers

(2) Figure 6. The interrupter can now be removed

contact pressure at the hinge.

Every 20,000 Operations or Approximately
Every Five Years-Whichever Comes First:

etc., will be found that cannot be identified in
reassembled correctly.

Remove the assembly bolts 5 (2, 6„ 9, 11,
13, 16, and 19) Figure 18.

Remove the side brace (7), rear brace

To remove the upper supports (12), and

upper interrupter support (15), remove

the assembly bolts (1 and 14), sind the

inspection and overhaul as required. All
excessively worn parts in both the mech

bolted connection between the upper in

terrupter support and the blow-out coil.

anism and breaker should be replaced.
Such wear will usually be indicated when

(5), the upper pole pieces (3), and the

lower pole pieces (8).

The breaker should be given a general

the breaker cannot be adjusted to indicated

When disassembling the arc chute

these instructions.
Care should be taken to
collect and identify these items so they can be

assembled in the castle nut on the hinge

(To inspect or replace blow-out

coils and arc runners):

be e^qjected 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. Small broken

lubricant D50H47.

REPLACEMENT

Insulating material that is carbonized and

cannot be satisfactorily cleaned should

6. Any parts damaged or severely burned
and/or eroded from arc action should

REPAIR AND

removing and replacing those parts of the breaker
subject to damage and wear that may require
repair or replacement at the installation. IM

are tight.

as described under

The stationary primary contact fingers

The arc runners should be inspected and

been reduced to 25% of the original meUl
thickness as a result of arc erosion. On
arc runners with arc resistant surfaces,

D50H15

LUBRICATION.

ness.

mechanism and breaker

All roller and needle bearings in the

examined and if the insulation has been

other, the coils should be replaced. All

operating parts.

Remove the assembly bolt (22) to remove

Magne-Blast Circuit Breaker GEI-77055
' the lower brace (10).

Remove the lower interrupter support (20)

by removing the assembly bolts (21)
Figure 18 and the connection nut (7)
Figure 20.

At this point, the side shields (4) Figure
20, and the upper arc runner assembly
(2) can be removed. On the "-6" design
the throat coolers (8) Figure 19B, are

permanently affixed to the side shields.

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

done by removing the various screws and
assembly bolts (not illustrated) as shown
in Figure 19.

The arc chute sides (6) Figure 19, can
also be separated for inspection.

9. On the "-6" design, do not disassemble the
muffler assembly (4) Figure 18.

Reassemble the interrupter in the reverse order.

The following items should be noted during re
assembly.

Figure 18A, (8036083)""-4" Design

•V/

/fy\- ' ./

Figure 18B. (8038702) Early "-6" Design

Figure 18C. (8039512) Later "-6" Design

Figure 18. Internjpter Assembly
Assembly Bolts
Assembly Bolt
Upper Pole Pieces

Upper Interrupter Support

Upper Insulation.
Side Shield

Assembly Bolts

Lower Interrupter Support
Assembly Bolts

Assembly Bolt

GEI-77055 Magne-Blast Circuit Breaker
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
should be parallel and in line.

The gap between the fins at the rear of
the arc chute sides measured at least
1" in from the back end of the arc chute

(See Figure 21) should be 3/64" to 3/32"

on the "-4" design and 0 to 1/16" on the
"-6" design interrupter.

Check to insure that electrical connections
to the blow-out coils are tight.
When reassembling the arc runner as

semblies, check that the snacers (1 and
11) Figure 19, are correctly installed.

Before bolting the upper supports in
place, make certain that the upper arc
runner assembly is tight against the arc
chute side so that the gap between the

. ^r[

Figure 19A. (8021965) "-4" Design

F^re 19B. (8038701) "-6" Design

Figure 19C. (8039510) Later "-6" Design

Figure 19, Interrupter Assembly with Side Removed
Upper Arc Runner Spacers
Upper Arc Runner Assembly

Arc Chute Side

Upper Insiilation

Blow-out Core
Blow-out Coil

8.
9.

Throat Cooler
Lower Arc Runner

Upper Arc Runner

10.

Lower Insulation

Lower Arc Runner Spacers
Lower Arc Runner Assembly
Lower Coil Connection

Magne-blast Circuit Breaker GEI-77055

upper insulation (7) Figure 19, and the
arc chute sides (6) is a

minimum.

the "-6" design the throat coolers (8)
should also be assembled tightly against
the arc chute sides.

Make certain that the electrical connec
tions are tight.

as described under INTERRUPTER REMOVAL AND

REPLACEMENT, page 16.

=) ^

qP>- i,

CONTACTS

Open the breaker and remove the box barriers

and interrupters as previously described.
move the contacts, proceed as foUov/s:

Disconnect the contact braids (7) from
the contact fingers by removing two bolts
and locking plates (8).

Grasp the lower end of the contact fingers

with pliers
downward

and

pull contact assembly

remove from

stud assem

bly.

Figure 20. (8029831) Interrupter Assembly
1.

Upper Support

Upper Arc Runner Assembly

Upper Arc Runner

Side Shield

Lower Arc Runner Assembly

6.
7.

Lower Coil Connection
Connection Nut

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 reassem

bled 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.

Reassemble in reverse order, re-using
the shims and spacers.

Close the breaker slowly to check that
the movable arcing contact is approxi

mately centered on the stationary arcing
contact and that it does not rub on either

side of the throat barrier (9).
NOTE:
Whenever it is found necessary
to replace arcing contacts on any pole of
a

recommended that both

and movable contacts on

that pole be replaced at the same time.

Figure 21. (8029373) Arc Chute Fin Spacing

GEI-77055 Magne-blast Circuit Breaker

•

-a

Figure 22. (8025170) Rear Bushing Assembly
1,
2,

Rear Bushing
5.
Guide and Support for Interrupter 6.

Bolts for Contact Support

Contact Support

Bolt for Flexible Braid
Mounting Bolt
Flexible Braid
Connection Bolt

Compress the contact spring (6) by use
of the spring compressor,

Remove spring and spring guide (1).

Raise

the contact finger to clear the
primary contact stop plate (8) and lift

12.

Insulating Plate

so that it is retained by stop plate (8).

Open spring compressor (3) andassemble
spring guide, spring and spring com
pressor (Figure 24A).

Turn nut (2) in clockwise direction to

compress contact spring (Figure 24B).

Hold spring firmly in yoke on spring
compressor to prevent spring from slip

the firmer out of contact support (7).
Remove

Stud for Mounting Arcii^ Fingers
Stationary Arcing Contact Assembly
Spring Baffle

then place it on the contact support (7) ^

Stationary Primary Contacts (9) Figure 24.
1.

9.
10.
11.

one contact finger at a time.

ping out of the compressor.

To replace the Stationary Primary Contacts:

4.
1.

Apply a thin coating of D50H47 grease
on Uie hinged edge of the finger (9)

Place washer (not shown) on guide on

top of spring, place top of guide into
hole in spring retainer (4) and the round

Magne-bl^t Circuit Breaker GEI-77055
end of spring guide in cutout in primary

finger (Figure 24C).
5.

Hold

spring

assembly firmly in place

and remove spring compressor.

Movable Primary Contacts (10) Figure 23.

To replace the movable primary contacts
on

Disassemble nuts from assembly bolts

(11) and remove the movable primary
contacts (10).
2.

ifii

Reassemble in reverse order.

To replace the movable primary contacts
on a 2000 ampere breaker it is first necessary
to disassemble the movable arcing contacts,
then proceed as follows:

ugfT

>.-ti>aagg.

Disassemble operating rod pin (4), first
noting quantity and location of washers
in the assembly.

Pry contact arms (8) apart enough to
disengage pivot pins of piston assembly
(13) allowing piston to drop down into
its booster cylinder.

Rotate the two parts of the contact arm
assembly away from each other so as
sembly bolts (11) are accessible and
movable primary contacts (10) can be
removed.

Reassemble in reverse order.

E. Contact Arm Assembly (8,10,13,14 Figure 23).
1.

Remove connection bar (15).

Disassemble hinge pin (7), cup bearing (6),
and operating rod pin (4) noting quantity
and location of any washers and spacers
used in assemblies.

The contact arm assembly including the

piston assembly (13) can now be removed.
4.

When reassembling, first insert piston

tube assembly (13) into the booster cyl
inder and reassemble the cup bearing,

making sure the silvered contact washers
between the bushing and contact arms
(both sides) are in place.

Reassemble operating rod pin (4) and
connection bar (15).

^F. After
disassembly and reassembly of any
contacts, check all contact adjustments as
described under ADJUSTMENTS.

Figure 23. (8038805) Contact Assembly
1.
2.

Front Bushing
Contact Springs

3.
4.

Stationary Primary Contacts
Operating Rod Pin

Buffer

6.
7.
8.
9.
10.
11.

Cup Bearing
Hinge Pin
Contact Arm
Throat Barrier

Movable Primary Contacts
Assembly Bolts

Movable Arcing Contact

15.

Connection Bar

rj-r.

GEI-77055 Magne-blast Circuit Breaker

Figure 24. Method of Installing Primary Contact Springs Using a Spring Compressor
1.

Spring Retainer
Assembly Bolts

Spring

Contact Support

Stop Plate

Stationary Primary Finger

Magne-blast Circuit Breaker GEI-77055BUSHINGS

IMPORTANT:

barriers
scribed.

and interrupters as already de-

DO NOT REMOVE ALL SEX

BUSHINGS AT ONCE. The bushings have been
carefully aligned with the breaker frame, during
assembly at the factory, and it is important that
this alignment be maintainedto insure interchange-

barriers (14 and 18) Figure 6.

ability of the breakers in the metal-clad units.

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, so that it may be
reinstated in the same location.

Remove the connection bar (15) Figure23,
cup bearing (6) and hinge pin (7).
Remove the four bolts at the mounting

flange of the front bushing being removed,
and lower the bushing. (See note under
rear bushings concerning use of shims).
5.

When reassembling, first mount the bush

ing and assemble the cup bearing (6),
contact arm (8), and replace pin (7) being

However, it is possible to remove and re
assemble three busMngs at one time.
If this

sure the silvered contact washers between

is preferred, alignment of the bushings may be
accomplished by placing the breaker in a deenergized spare metal-clad unit before tightening
the bushing mounting bolts. This must be done
before the interrupters are reinstalled.

To replace the bushing, proceed as follows:

Remove the upper and lower horizontal

the bushing and contact arms are in
place. The contact surfaces at the hinge
point of the contact blade and bushing
should have a thin coating of D50H47
grease.

Check all contact adjustments as outlined
under ADJUSTMENTS.

Rear Bushing
1.

TRIP SHAFT AND LATCH (3 & 4 Figure 9).

Open the breaker and remove the box

Remove the upper and lower horizontal
barriers (14 and 18) Figure 6.

Remove the four bolts at the mounting
flange of the rear bushing being removed
and lower the bushing assembly.

NOTE: Shims may be found between the
breaker mounting plate and the bushing
mounting flange on some, or all bolts.
These shims are for squaring up the
bushing and may be required when new
bushings are assembled.

Remove two bolts (3) Figure 25 and let
the trip coil (1) and support (2) hang frefe.
Remove latch check switch bar (5) Figure

Remove snap rings and washers adjacent
to bearings on both sides of mechanism
frame.

Using a 3/8" diameter brass rod approxi
mately 15" long, drive the bearing hous
ings out of the mechanism frame. Take

Referring to Figure 24, disassemble the
primary contact springs (6) as previously

the right bearing out first using the
opening in the left side of the frame and
then remove the left bearing using the

Disassemble the spring retainer (4) by
removing mounting bolts (5).

Referring to Fi^re 22, disassemble the

opening made from the removal of the
right bearing.

When removing the left bearing, the brass
rod may require a slight bend to clear
the trip latch.

contact support (4) and interrupter mount
ing bracket (2) removing two bolts (3).
Reassemble in the reverse order.

Do not remove wiring.

26, the trip coil plunger bracket (6), and
manual trip bar (1) Figure 3.

described.

Remove mounting bolts for control device
Figure 3, letting the control device hang

NOTE:
The trip shaft bearings are a
self-lubricatii^ type and do not require

The

interrupter mounting bracket (2) is not

lubrication. '

symmetrical and must be assembled cor

rectly to orient the interrupter properly
on the breaker. The longest projection
of the bracket should be toward the lower

end of the bushing.
Front Bushing

Open the breaker and remove the box

If the trip latch is to be replaced, remove
the set screw holding the latch on the
shaft.
Place a block between the latch
and the mechanism frame.
Drive the

trip shaft out of the latch imtU the key
can be removed.

Check for and remove

any burrs raised around the keyway to
avoid possible damage to the bearings.
27

GEI-77055 Magne-blast Circuit Breaker
7.

Reassemble parts in reverse order. Be
sure the spring is in the proper place
and has been wound one-half turn. Also
make sure the latch is in place on stop
bar roller before bearings and trip shaft

are reassembled. A pipe should be used
to drive the bearing back into the mech
anism frame so that damage does not
occur to the bearing surface.
Trip Latch Roller Bearing
1.

Remove mounting bolts on control device

Figure 3, leaving control device hang

paid to the location of washers and spacers.
6

cedures.

Closing Coil

The closing coil is contained within the solenoid

pot (1) Figure 27. To remove the closing coil,

proceed as follows:
1.

Open the breaker,

Remove the two closing coil leads (11).

free. Do not remove wiring.

To reassemble, reverse the above pro

Remove the terminal board (2) from the

solenoid pot and let it hang by the wires.

Also, remove the wires from strap (3). ^

Place block between manual trip rod (6)

Figure 2, and trip paddle (1) Figure 3

on trip shaft. This holds trip shaft m
trip position and allows trip linkage to

• be free.

Working through hole on left hand side
of mechanism, remove snap ring and

NOTE;

Slide trip roller pin just enough to the
right to 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 screwdriver to
complete the removal of snap ring.

. Armature rests on stop nuts

(12) only. Armature should be supported
during the removal of these stop nuts

washer from trip roller pin (3) Figure 9,
using snap ring pliers.

Remove the stop nuts (8 and 12) on guide
studs (6), lower the armature (7) and
control device trip plunger (5),

and then lowered.

Loosen the four nuts under the bottom

plate (4) approximately 1/2".

Support

the bottom plate with a rope sling or hoist
and remove the two rear nuts.

Trip roller bearing can now be removed

5. Remove the nuts (9) at the top of the 0

for lubrication (See section on LUBRI
CATION). Particular attention should be

plate, closing coil, solenoid pot (1) and

front studs.

This permits the bottom

Figure 25 (8029371) Potential Trip Coil
1.

Trip Coil

2.
3.
4.

Trip Coil Support
Mounting Bolts
Trip Coil Leads

Figure 26 (8020728) Opening Sprir^ Assembly
1.

Pivot Pin

2.
3.

Opening Spring Unit
Trip Coil Mounting Plate

4.
5.

Pivot Pin
Switch Bar

Trip Coil Plunger Bracket

Magne-blast Circuit Breaker GEI-77055

control device plunger guide (10) to toe

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

Remove the trip coil (1).

After reassembling (in the reverse order)
check the primary contact gap adjustment
as explained under ADJUSTMENTS.

removed.

To reassemble^ first place the closing
coil and spacers on the bottom plate (4).
Raise into position, inserting the control
device plunger guide (lO)andcompressing
the piston ring on the upper pole piece.
Tilt the bottom plate downward and re

place the solenoid pot (1) and two front
studs and nuts (9).

Interlock Switch

Tighten the four nuts under the bottom
plate taking special precaution to center

remove the two mounting screws and disconnect

the closing 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
rod (5) and armature (7).

10. Recheck the mechanism adjustments as
e:q}lained under ADJUSTMENTS.

To remove the interlock switch (7) Figure 10,
the lead wires.

Reassemble in the reverse order

and check the switch adjustments as explained
under ADJUSTMENTS.

Latch Checking Switch

To remove the latch checking switch (2) Figure
10, (when furnished) remove the two mounting
screws and disconnect the lead wires. Reassemble

justments as explained under ADJUSTMENTS.

To replace the potential trip coil (1) Figure
25, proceed as follows:

Cut-off Switch

Open the breaker and remove the opening
spring unit (2) Figure 26, by removing
the pivot pins (1 and 4).

Cut wires at butt connectors (4) Figure 25.

To remove the cut-off switch (1) Figure 5
remove the two mounting bolts and disconnect the

lead wires.

When reassembling check the cut-off

switch adjustment as explained under ADJUST-MENTS.

"V
n
jn_9
Solenoid Pot
Terminal Board

Wire Strap
Bottom Plate

Control Device Trip Plunger
Guide Studs
Armature

Stop Nuts
Front Stud Nuts

1 rW
12.

Figure 27. (8022045) Closing Solenoid Assembly

Plunger Guide
Closing Coil Leads
Stop Nuts

GEK-77D55 Magne-blast Circuit Breaker

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 interruptions
caused by breakdowns, and saves time and ejqpense.
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 th,e original parts since improve
ments are made from time to time.^ The parts

ORDERING INSTRUCTIONS

data of both the breaker and the mech
anism.

description of each part ordered, and

NOTE:! The listed terms "Right" and "Left"

Standard hardware, such as screws, bolts,

nuts, washers, etc., are not listed and
should be purchased locally.

apply when facing the mechanism end of the breaker.

Specify the quantity, catalog number (if
listed), reference number (if listed), and
this bulletin number.

which are fui^shed, however, will be inter
changeable. / /

Always specify the complete nameplate

For prices, refer to the 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 mechanism which are usually recommended for stock for
normal maintenance. C^er parts can be obtained by contacting the

nearest office of the General Electric Company.

Magne-blast Circuit Breaker GEI-77055
RECOMMENDED RENEWAL PARTS FOR TYPE MS-13 SOLENOID MECHANISM

USED FOR AM-13.8-150/250/500-4 (*), -6 (»)
1200 & 2000 AMPERE

# 125 V-dc &.230 V-ac, 60 Hz (500 MVA)
125 V-dc & 230 V-ac, 60 Hz (150/250 MVA)
#250 V-dc (500 MVA)

250 V-dc (150/250 MVA)

0802B0799G001
0802B0799G002
0802B0799G003
0802B0799G004

Potential Trip Coil ♦ *

Undervoltage Device Coil * *
125 V-dc

Control Device Coil * *

230 V-ac, 60 Hz (Continuous)
230 V-ac, 60 Hz (Intermittent)

006275017G033

Current Trip Coil
3 Amp., 60 Hz

Refer to nameplate or summary for proper voltage and current rating.
#

Used also on certain 150 & 250 MVA breakers with high current closing coil.

Some "-4" used 006174582G014.
31

RECOMMENDED RENEWAL PARTS FOR MAGNE BLAST BREAKERS
TYPES

AM-13.8-150/150A-4 (•)

AM-l3,8-250/250A-4 (*), 6 (*)

AM-13,8-500/500A-4 (*), 6 (♦)■
1200 and 2000 Amperes

(•Suffix Letters - S, U, B, R, V)

NOTE- On Breakers with suffix "-6" (*) two (2) different Design Interrupter Assemblies have
been furnished. Refer to Figures 18 and 19 to determine correct Renewal Part References.
Fig.
No.

6
6
22
22
22
22
22
23
23
23
23
23
23
23
23
23
23
23.
23
23
23
23

Ref.
No.

19
29
7
7

12
12
10
2
2
2
2
2
3
3
3
3

3
9

23
23
23
23
23
23
23
19A
19A
19A
19B
lOB

19B
19B
19C
19C
19A
19B
190
*
•

•

AA
*

12-73

10
10
10
10
10
10
10
10
14
13

13
7
7
7
7

7
8
8
7 & 8

7 & 8
10
10
10

Ampere Type
Elating
AU
All
All
All
All
AU
AU
1200

AU
AU
All
All

1200
1200
2000
2000
1200
1200

B
B
AU
All
AU

1200
2000
2000
AU
1200
1200
1200
1200
1200
2000
2000

B
AU
All
AU
AU
AU

2000
AU
1200
2000
AU
AU
AU
AU
AU
AU
AU
AU
AU

AU
AU
AU
AU
AU
AU
AU

AU
A

Catalog No.ForTypeAM-13.8-(MVA)
-6

-4

0281B0708G001
0263B0292P002
0236C0791G001
0236C0791G004
0414A0116P004
0108B1937P005
0236C0790G009
0414A0180P001
0121A5964P001

0281B0708G001
0263B0292P002
0236e0791G001
0236C0791G004
—

•

—

0236C0790G009
0414A0180P001
—

0121A5964P001
006509787P001
0121A5964P001

0114C5382P002

0114C5382P002
0114C5382P002

0114C5382P002

—

0114C5382PC02
0195A7388G002
0137A9164P003
0137A9164P004

—

0137A9164P003

0137A9164P004
0114C5382P004
0114C5382P004

B
AU
All
AU
All
AU
All
AA

V
V

AU
AU
AU
All
All
AU
All
AU
AU
AU
AU

AU
AU

••

•

0137A9164P003
0137A9164P004
0802B0742G003
0236C0792G031
0236C0792G015
0414A0ig4P002
0108B1937G001
0108B1937G002
_

—

0227A5306G004
0213X0343G094
0213X0343G094
—

—

0195A7349G001

0195A7349G002
0114C5442G001
0114C5442G002
0132C2737G001
0132C2737G002

0456A0336P001

—

0456A0336P001

0132C2735P007
0414A0116P002
0421A0201P001
0265C0163P009
0802B0735P001

0108B5520P001
0421A0201P001
0265C0163P009

0802B0735P001

No.

Req.
3
3
3
3
3
3
3
12
12
18
24
18
12
12
18
24
18
3
3
3
3
3
6

6
6
6
3
3
3
6
3
3

3
3
3
3
3
3
6
6
6
3

6
6
6

All Except Breakers with "B" in Suffix
All Except Breakers with "V" in Suffix
Not Illustrated

GENERAL ELECTRIC COMPANY, PHILADELPHIA, PA

Description

Operating Rod Assembly
Booster Cylinder

Flexible Connector (Right)
Flexible Connector (Left)
Insulating Plate
Insulating Plate
Arcing Contact Assembly
Primary Contact Finger Spring
Primary Contact Finger Spring

Primary Contact Finger Spring
Primary Contact Finger Spring

Primary
Primary
Primary
Primary
Primary
Primary

Contact
Contact
Contact
Contact
Contact
Contact

Finger Spring
Finger
Finger
Finger
Finger
Finger

Throat Barrier Assembly
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact

Movable Primary Contact
Movable Primary Contact
Movable Arcing Contact
Tube & Piston Assembly
Tube & Piston Assembly

Upper Shield

Upper Shield (Right)

Upper Shield (Left)

Upper Shield Assembly (Right)

Upper Shield Assembly (Left)

Throat Cooler Assembly (Right)

Throat Cooler Assembly (Left)

Shield & Cooler Assembly (Right)

Shield & Cooler Assembly (Left)
Lower Runner Barrier

Lower Runner Barrier
Lower Runner Barrier

Insulating Plate
Lower Runner Shield

Upper Runner Insulation
Lower Runner Insulation

.•x""" 'V
-•4-

GEP>4440
r

RENEWAL PARTS

MAGNE-BLAST CIRCUIT BREAKER
TYPE AM-13.8-500-7

NOTE: The ML-13 Mechanism is not included in this publication.
Refer to GEF-4379 for ML-13 Mechanism renewal parts.

ORDERING INSTRUCTIONS

I. Always specify complete nameplate dataof the breaker.

Ser.""®

('t listed), reference number (if listed), description, and this bulletin

'• sSrb?p"rc"hredbulletin. Such items
4. For prices, refer to the nearest office of the General Electric Company.
Wh«n erdtring r*ii*wal parti, giv* quantity, catalog numbar, datcription el each

GENERAL B
lo »ubi»ef to (hano* without nolle#.

item raquirad, end camplata nnmapleta reading.

ELECTRIC

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKER

CEF-4440

\
(21. FIG.2)

Breaker, Type AM-13.8- 500
\

Hinge pin assembly (Ref. No. 10)

Pig. 1. Cross-seclion views of breakerand hinge pin

NOTE: For recommended parts for normal maintenance, refer to back cover,
rev.
A.M-13. ft-SOO BREAKER (REFER TfJ
O FKJ.
FKJ. 1)
1)
Ref. No.
1
2
2
3
•4
5
6
7

8 •
9
10

Catalog Number for
1200 Ampere
2000 Ampere

Type

, 073-152C5910G00i"'

All
A

132C2738(F003
132C2738P004
802B0764G001
265C0162P017
281B0708G001
263B0292P002
2S8C0619G012
688C0589P001
845D0123G003
898B0282G001

B
All
All
All
AU
All
AU
AU
AU
T

A All except breakers with "B" in suffix
* Not iUustrated

073-152C5910G001
132C2738P005
132C2738P005
802B0764G001

26SC0162P017
281B0708G001
263B0292P002
258C0619G012
688C0589P001
958C0683G003
898302820002

No.

Req'd
3
6
6
3
2
3
3
3
-3
3
3

Description
Box barrier

Horizontal barrier
Horizontal barrier
Vertical barrier
Side barrier

Operating rod assembly
Booster cylinder

Interrupter clamp
Connection bar

Front bushing
Hinge assembly

type AM-13.8 MAGNE-BLAST CIRCUIT BREAKER

Fig. 2. Rear busking assembly (Re/. No. 20)

REAR BUSHING ASSEMBLY (REFER TO FIG. 2 AND 4)
Catalog Number for

1200 Ampere

073-213X0344G052

213C0344G053

2000 Ampere
073-213X0344G054

B45D0124G003.- ^

213X0344G054
958C0684G005^

236C0791G001

238C0791G002
236C0791G00I
236007910004

236C0791G004 $
152C5907G001 5

Description

152C5907G001
238C790G9
6445087P004
65S7243P002
6557243P002

Rear bushing assembly
___Beax bushing assejpbly

I
,
.

Re55.e connector, right
Arcing contact support
stationary arcing contact
Rii»fpr clamp

Primary contact finger spring

121A5964P001

Primary contact finger spring

114C5382P002
114C5382F002

H4C5382P002
828C0782P013

962C0778P002

962C0778P002
258C0666P009
962C0778P011

962C0778P002 ^
962C0778P011
962C0778P011

N312P2542B

Primary contact finger
Primary contact finger

Primary contact finger
Contact finger retainer
Contact finger retainer
uontact support

contact assembly"' "^

962C0778P007
195A7388G002

962C0778P007 ©

132C2722P005

132C27221STe>b^

a All except breakers with "B" in suffix

195A7388G002

^ring guide
-

spring retainer
Spring retainer

Throat barrier assembly
Baffle

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKER

GEF-4440

RECOMMENDED PARTS FOR NORMAL MAINTENANCE
Fig.
No.
1
1
3
3
3
4
4
4
4
4
4
3
4
4
4

32
32
32
37
108
108
108
108
107
109
89

90
78
81
76
•77
•80
•79

B
AU
AU

B
All
All
AU
AU
AU
AU
AU
AU
AU
AU
AU

263B0292P002
236C0791G001
236C0791G004
236C0791G002
414A0180P001
121AS964P001

263B0292P002
236C0791G001
236C0791G004
236C0791G002

108BS543G001
213X0343G092
132C2737G009
132C2737CH)10
132C2735P007
108B5S20P012
134C3547P016
134C3547P017
265C0163P009

802B0735P001

3
3
3
3
3
12

121A5964P001

114C5382Pa02
195A7388G002

12
18
18
3

114CS382P002
114C 5382 P002

195A7388G002
137A9164P003
137A9164P004
114CS382P004

No.

Req'd

114CS382P004
108B5543G001
213X0343G094
132C2737G009
132C2737G010
132C2735P007
108B5520P012
134C3547P016
134C3547P017
26SC0163P009
802B073SP001

3
6
6
3
3

3
3
6
3
3
3
6
6

Description

Operating rod assembly
Booster cylinder

Flexible connector, right
Flexible connector, left
Arcing contact assembly

Primary contact finger spring
Primary contact finger spring
Primary contact finger spring
Primary contact finger
Primary contact finger
Primary contact finger

Throat barrier assembly
Primary
Primary
Primary
Primary

contact
contact
contact
contact

Arcing tip, movable

Tube and piston assembly
Throat cooler assembly, right
Throat cooler assembly, left
Lower runner barrier

hisulating plate

Lower runner shield, right
Lower runner, shield, left
Upper runner insulatton
Lower runner insulatimi

• Not iUustrated

GENER.AL ELECTRIC COMPANY

SWITCHGEAR BUSINESS DEPARTMENT
PHILADELPHIA, PA 19142

MAGNE-BLAST CIRCUIT BREAKER
TYPES

AM-13.8-500-5A
AM-13.8-500-5AB
AM-13.8-500-5C
AM-13.8-500-5CB
AM-13.8-500-5H
AM-13.8-500-5HB

Receiving, Handling
and Storage
Installation.

Description of
Operation....

Adjustments
General Maintenance,

Renewal Parts

SWITCHGEAR

DEPARTMENT

GENERAL^ELECTRIC
PHILADELPHIA,

PA.

GBI-88764
MAGNE-BLAST CIRCUIT BREAKER

AM-13.8-500-5 (^)
^ Letter Designation A, B, C, and

used Immediately following

the model number Indicates basic design features.
INTRODUCTION

The magne-blast circuit breaker Is the removable Interrupting element
for use In vertlcal-llft metal-clad swltchgear^ to provide reliable
control and protection of power systems. Among the many advantages of
metal-clad mrltchgear 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 Interchangeablllty 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 I t Into Intimate contact with cool dielectric ma-

tezdal.

A sturdy, reliable operating mechanism assures low maintenance

and long life.

The AH-13.8 magne-blast breaker Is available In a number of current
ratings. Refer to the breaker nameplate for the complete rating Infor
mation of any partlcxilar breaker. The short circuit conditions to be
Imposed on the breaker must not exceed Its rating, nor should It be
csdled 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 typlceiL, unless
otherwise specified.
PROPER INSTALLATION AND MAINTENANCE ARE NECESSARY TO INSURE CONTINUED

SATISFACTORY OPERATION OP THE BREAKER. The following Instructions will
provide coag>lete Information for placing magne-blast breakers In ser
vice and for maintaining satisfactory operation.

These Instructions do not purport to cover £ai details or variations
In equipment 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 ax'lse
which are not covered sufficiently for the purchaser's purposes, the
matter should be referred to the General Electric Company.

GEI-88764
RECEIVING. HANDLING. AND STORAGE
Receiving and Handling

Each breaker Is carefxilly Inspected and packed by workmen experienced
In the proper handling and packing of electrical equipment. Immediate
ly 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 dameige claim should be filed Immediately with the transpor
tation company and the nearest General Electric Sales Office should be
notified.

It Is e:q)ected that due care will be exercised during the unpacking
and Installation of the bresiker so that no damage will occur from care
less or rough handling, or from exposure to moisture or dirt. Loose
parts associated with the breaker are alvays Included In the same crate.
Check all peu>ts sigalnst the packing list to be sure that no p£u>ts 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 pre
cautions must be taken to Insure the proper storage of the breaker:

1. The breaker should be carefully protected against condensation, pre
ferably by storing 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 operation to prevent
condensation.

2. The breaker should be stored In a clean location, free from corrosive
gases or fumesj particular care should be taken to protect the equip

ment from moisture zuid cement dust, as this combination has a very
corrosive effect on many parts.

3. Machined parts of the operating mechanism, 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 luifavorable

atmospheric conditions, steps should be ttiken to dry out the breaker

before It Is placed In service.
INSTALLATION

1. Remove the box barrier and front cover and make a vlsusQ Inspection
to ascertain that the breaker and mechanism Is In satisfactory con
dition.

Check all bearing surfaces of the mechanism for lubrication.

Refer to section on Lubrication (page 15).

csi-88|6%

2. Charge the breaker closing springs manually using a 5/8" ratchet
wrench to turn the driving eccentric (6) Fig. 4. Turning the eccen
tric coxmter clockwise will advance the ratchet wheel and congress
the springs.

When the ^^rlngs have reached the fully charged position the Indi

cator (10) Fig. 4 will read "CHARQED"« and the driving pawl will be
raised from the ratchet wheel teeth.

Additional turning of the ec

centric will not advance the ratchet wheel.

Insert the spring blocking device (4) Fig. 4 and manually discharge
the springs against the pins by pushing the manual release button
(1) Fig. 4. The springs are now blocked and slow closing of the
breaker contacts can be accomplished by again turning the driving

eccentric with a 3/8 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 se
curely In the closed position^ and that It trips freely when the manusd trip lever Is operated. The breaker should not be operated
electrically until It has been operated several times manually to

Insure freedom of action.

At this tlme« also check the following

adjustments:

f^.

a. Primary contact wipe
b. Arcing contact wipe

Refer to page 7]

c. Primary contact gap

Refer to page 7]

Refer to page t]

"DO NOT WORK ON EITHER THE BREAKER OR HBCHANISH UNLESS THE CLOSING
SPRINGS ARE BLOCKED AND THE OPENING SPRINGS HAVE BEEN TRIPPED OPEN
OR MECHANICALLy BLOCKED. THIS PRECATTTION IS REQUIRED TO PREVENT
ACCIDENTAL CLOSING OR TRIPPING."

After the adjustments have been checked, the springs can be imblocked. Rotate the driving eccentric until the Indicator reads
"CHARGED" and the ratchet wheel no longer Is advanced. GSie blocking
device can now be removed.

3. Attach test coupler to circuit breaker and operate electrically
several times. Check the control voltage as described under "CON
TROL POWER CHECK".

NOTE: If the breaker secondary wiring Is to be given a hl-potentlal
test at 1300 volts, remove both the motor leads from the termlneO.
connection. Failure to disconnect the motor from the circuit may
cause damage to the winding Insulation.

4. Remove the test coupler and replace box barrier.

OEI-88764

5. If breaker has been stored for a long period of tlmej it is recommended that the insulation be checked with a standard 60 cycle high ^

potential test.

Refer to Insulation Test (page 13).

6. Lubricate the silver portion of the primary disconnect studs by

rubbing a small amount of contact lubricsuit D30H47 to form a thin
coating on the ball contact.

7. Refer to metal-clad instruction book OEH-1802 for final instructions
before inserting the breaker into the metal-clad unit.
DESCRIPTION OF OPERATION

The magne-blast breaker is con^osed 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 interrtq>ting units from each other to provide insulation between
phases as well as from each phase to ground. The primary connections
to the associated metsQ-clad equipment are made through the primary
disconnect studs.

The ML-13 operating mechanism shown in Figures 1, 2, and 3 is of the

stored energy type designed to give high
The mechanism will operate on a-c or d-c
breaker name plate. Closing and opening
electrically by the metal-clad or remote

speed closing and opening.
voltage as indicated on the
operations are controlled
relaying, and mechsuiically

by the manual close and trip levers on the breaker. All secondary
connections from the breaker to the metal-clad unit are made through
the coupler (l) Pig. l.

A positive interlock (2) Pig. 3 and interlock switch (2) Pig. 1 are

provided between the breedcer and metal-clad unit to prevent raising
or lowering of 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 raised or lowered position.

A plunger can also be provided to

operate an additional auxiliary switch mounted in the metal-clad unit.

The operating mech£uiism used on those breakers designed for MI-6 metalclad equipment differs somewhat from those designed for M-36 equipment
but, its operation is principed.ly the same. These breakers are identi
fied by the "A" suffix in the breaker nomenclatiu*e.
This mechanism is controlled by a relay in the metal-clad unit to make

it compatable with solenoid operated breakers. Two seven point ter
minal secondary couplers also replace the one sixteen termineU. coupler.
The positive interlock between the breaker and metal-clad unit is re

placed with a trip interlock that trips the mechanism before raising
or lowering of the breaker ceui be accomplished. A fork-type lever can
be furnished to operate an auxiliary switch mounted in the metsd-clad
init. Motor circuit fuses are mounted on the breaker for protection.

GEI-88764

When the breaker Is interchangeable with MS-13 solenoid operated
breakers in M-36 metal-clad units, motor circuit fuses are mounted on
the breaker for protection. These breakers are identified by the "C"
suffix in the breaker nomenclature.
Spring Charging

The mechanism consists of a high speed.gear motor that compresses a
set of closing springs through the action of a simple eccentric, ratch
et, cuid pawl assembly. The rotary action of the motor (2) Pig. 4 is
converted to a short straight stroke pumping action through the eccent

ric (6) and a lever that carries a spring loaded driving pawl (5).

The pawl advances the ratchet wheel (3) Pig. 3 only a few degrees each
stroke where it is held in position by the latching pawls (1}.^ When
the ratchet wheel has been rotated approximately loO degrees the clos

ing springs (6) will be fully compressed.

As the ratchet wheel con

tinues to rotate, the spring load will shift over center and attempt
to discharge. After only a few degrees of rotation, the closing roller

(10) Pig. 1 will engage the closing latch (11) and the compressed
springs will be held in repose until a closing operation is required.
During the last few degrees of the ratchet wheel rotation the motor

and interlock switches (6) are released and the driving pawl is raised
from the ratchet wheel surface. This allows the motor and driving
mecheuiism to coast to a natural stop ejcpending all residual energy.

During the time the springs are being compressed a relay (6) Pig. 6
locks the closing power circuits open and the relay will remain ener
gized until the springs are fully charged and the control 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 eccentric in a counter
clockwise direction until the indicator reads "CHARGED" and the driving
pawl no longer engages the ratchet wheel. The use of the ratchet wrench
provides for maximum safety in the event that control power is suddenly
restored without warning. In this event, the motor drive will take over
£igain and continues to charge the springs.
Closing Operation

Closing the breaker is accomplished by energizing the closing solenoid
or by manually pressing the close button. In either case, the closing
latch is removed from the spring blocking location allowing the springs
to discharge. The energy of the springs is applied to the rotation of

a cam (I6) Pig. 3 that closes the breaker through a simple linkage that
remains trip free at all times. A monitoring switch (11) Pig. 6 on the
closing latch will start the spring charging motor after i t is fully
reset.

GEI-88764
Opening Operation

An electrlcea opening operation Is Initiated by energizing the trip
coll. This Is accomplished either by actuating the opening 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 coll, the trip plunger rotates the trip latch (7)j
Fig. 3, causing the operating mechanism linkage to collapse. The
energy stored In the opening springs Is thus released, opening the
breaker. During this operation, the trip coll circuit Is deenerglzed,
and upon completion of the opening operation, the operating mechanism
Is returned to Its normal position, ready for closing.

As the breaker opens, the main contacts part first, shunting the cur
rent through the arcing contacts. An arc forms as the arcing contacts

p«u»t.

See Pig. 7.

As the movable arcing contact (7) Is withdrawn

through the probes In the arc runner, the upper end of the arc Is trans

ferred to the upper arc runner (4). To assist the Interruption at this
point, a stream of air Is emitted from the booster tube (23) and forces
the arc onto the lower arc runner (8). Establishment of the arc on the
runners automatically Inserts the blowout colls Into the circuit. Intro
ducing a magnetic field between the pole pieces which tends to draw the
arc away from the arcing contacts. The Interrupter contains three up
per blowout colls and three lower blowout colls each Individually con
nected In series with Its respective section of arc runner. As the arc

Is forced outward along the diverging arc runners, the magnetic field
Is progressively Increased with the addition of each coll In the cir
cuit.

At the same time, the arc Is being forced Into the arc chute (3) which
Is composed of a series of gradually Interleaving Insulating fins.
These fins, which project alternately from the two opposite Inner sur
faces of the chute, elongate the arc Into a gradually deepening serpen- '
tine 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 maignltude and the phase angle of the current,
and at an early current-zero the ajco path Is so long and the gases pro
duced by the arc so cooled that the arc cannot reestablish Itself and.
Interruption occurs.

Manual tripping follows the same procedure except that Instead of ener
gizing the trip circuit, the manual trip (11) Pig. 2 Is used.
Trip Free Operation

If the trip coll circuit Is energized while the breaker Is closing, the
trip pluuiger will force the trip latch (8) Pig. 3 away from the trip

roller (9) causing the mechanism linkage to collapse and the breaker to
re-open. The closing cam (16) will complete Its closing stroke and the
springs will re-charge as In a normal closing operation.

GEI-88764
ADJUSTMENTS

All adjustments should be checked during periodic Inspections and when

ever it becomes necessary 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.

First, however,

remove the breaker from the metal-clad unit and remove the box barriers
and front cover.

"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. THIS MEASURE IS REQUIRED TO PREVENT ACCIDENTAL
CLOSING OR TRIPPING."
Primary Contact Wipe

When the breaker Is closed, as shown In Pig. 8, the stationary primary
contacts (l) should rise 5/l6"-|-0-I/16". Before checking this dimen
sion be sure the mechanism Is re-set so that the prop pin (13) Pig. 5
Is resting on the prop.

To obtain the proper contact adjustment, 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 Increase It. Tighten the check nut,
close the breaker and recheck the wipe. With the prlmcu:>y contact wipe

correctly adjusted, the clearance between the contact arm (6) and the
buffer block should be I/16" or greater (as shown In Pig. o) when the
breaker Is fully closed.
Arcing Contact Wipe

Refer to Pig. 8.

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 (l) and the movable primary
contact (2) should be 5/l6" or greater. This setting has been made In
the factory and no adjustment Is provided. A wipe of less than 5/l6"
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 between the probes on the upper euc*c runner without touching.
Primary Contact Gap

Refer to Pig. 9. 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 contact (6) should be 5-1/4"+5/16"—1/8".

To change this gap, loosen the check nut (17)> Pig. 5 and turn the
adjusting nut (I8) 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 mea
surement) .

GEI-88764
Trip Latch Vflpe

Refer to Pig, 5.

The wipe of the trip latch (8) on the trip roller (9)

should be from 3/l6" to 1/4". This can be measured by putting a film
of grease on the latch (8), closing the breaker part way^ and tripping.

The mechanism has the proper trip latch wipe when the latch rests

against the stop pin (23).

No adjustment is provided and a visu£il in

spection is usu£aiy all that is required.

If this setting is not cor

rect, look for insufficient travel of the trip shstft (7).
WHEN WORKING ON THE MECHANISM IN THE CLOSED POSITION, KEEP FINGERS
CLEAR OP THE LINKAGE, AS ACCIDENTAL TRIPPING CAN CAUSE SEVERE INJURY.
Trip Latch Clearance

Refer to Pig. 5.

With the breaker in the tripped position and the

closing springs charged, check the clearance between the trip latch (8)
and the trip roller (9). It should measure 1/32" to l/l6".
Prop Clearance

Refer to Pig. 3.

With the breaker closed as far as possible, that is,

with the springs blocked and the cam (l6) rotated so that the prop pin

(13) is at its maximum height over the prop (14), the clearance between

the prop and prop pin should be l/l6" to 5/32".

No adjustment is pro

vided and a visual inspection is usually all that is required.
Release Latch Wipe

Refer to Pig. 6. The wipe between the release latch (3) and roller (2)
should be 3/16" to 1/4". If re-setting is required, loosen, set, and
re-tighten adjustment nut and screw (4).
Release Latch Monitoring Switch

The release latch must be fully re-set and the monitoring switch opera
ted before the motor will start. The switch should be wiped by the
striker so that the clearance between the striker and switch mounting

bracket (20) Pig, 6 is 1/32" or less. To obtain this adjustment bend
the switch striker. Be sure the latch is fully re-set before making
euiy adjustments.

Motor and Relay Switches

With the closing springs blocked rotate the switch cam (1) Pig. 6 until
the switch striker (8) has traveled the maximum amount (about 180 de

grees rotation of cam). Loosen mounting bolt (14) and rotate switch
simport (15) until the gap between the striker (8) and support (15) is
1/32" or less.

a£I-88764
Interlock Switch Wipe

Refer to Fig. 10. Rotate the interlock shaft (l) manuailly clockwise
to release the Interlock switch ana (2). The point at which the con->
tacts make can be determined with a circuit continuity tester such as
a light Indicator or bell set.

To obtain adjustment on the Interlock

switch (3)« bend the Interlock switch arm (2) until there Is a maximum
of 1/32" clearance to the switch mounting plate (4).
Auxiliary Switch

The auxiliary switch (9)> Fig. 11 Is mounted on the left side of the
operating mechanism. The shaft of the position Indicator (8) operates
the auxiliary switch shaft which opens and closes the "a" and "b" con
tacts. The "a" contacts are open when the breaker Is open and the "b"
contacts are open when the breaker Is closed. The "a" contacts should
close when the breaker primary contact gap Is a minimum of 1". The "b"
contacts need only to be checked to see that they are open when the
breaker Is closed. No adjustment Is provided and a visual Inspection
Is usually all that Is required.
Driving Pawl Adjustment

The driving pawl (5) Fig. 4 must advance the ratchet wheel (3) Pig. 3
sufficiently on each stroke to allow the latching pawls (l) to fall
Into the ratchet teeth.

This should be checked with the maximum clos-

Ing spring load against the driving members.

With the mechanism un-

blocked, hand charge the closing springs with the manusQ. charging

wrench until they aa^e slightly more than half charged.

Slowly rotate

the charging wrench until the driving pawl (5) Pig. 4 has traveled

through Its return stroke and check the maximum clearance between the
pawl and the ratchet tooth. Rotate the charging wrench until the driv
ing pawl has advanced the ratchet tooth to Its maximum travel. Now
check the clearance between the ratchet tooth and the latching pawl

(1) Fig. 3.

The cle£u?ance should be approximately equal for both the

driving and latching pawls and not less than .015

In either case.

If adjustment Is required for either pawl the springs must first be

fully charged and blocked. Loosen seven motor support bolts (1) Fig.
15 and move entire motor assembly to the rear If the clearance is un
der the minimum at the latching pawls, and to the front If the clear
ance Is under the minimum at the driving pawl. Move the motor assembly
approximately twice the dimensional Increase required at the pawl. Be
certain the motor assembly Is moved stred-ght forward or rearward and
tighten the one bolt 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
above.

QEI-88764
AUXILIARY DEVICES

Latch Checking Switch

Refer to Fig. 12. Rotate the trip latch (4) clockwise (looking at the
left side of the mechanism) by pressing the manual trip lever to open
the latch checking switch operating arm (3)* Allow the trip latch to
reset slowly and determine the point at which the contacts make by using
a circuit continuity tester, such as a light Indicator or bell set.
The contacts of the latch checking switch should Just make when the

gap between the trip latch (4) and the stop pin (5) located on the
crank (7) Is l/l6". There should be a minimum of 1/64" between the
operating arm (3) Fig. 12 and the switch support (l). To obtain ad
justment of the latch checking switch (2) bend the latch checking switch
operating arm (3).
Plunger Interlock

Refer to Fig. 13.

With the breaker In the open position, the vertical

distance "A" from the top of the Interlock bolt (1) to the bottom of
the elevating bar (3) should be 10-7/32" plus or minus l/l6". To
change this adjustment, add or remove washers (2).
Auxiliary Switch Linkage

(Furnished l^eclal on Breakers With "A" Suffix)

Refer to Fig. l4. With the breaker In the open position, the distance
from the centerllne of the front bushing (l) to the center of the

S|^tch operating pin (2) should be 12^" as shown.

To change this set-

tlng, loosen the locking bolts (6), remove the pin (4) and turn the
clevis (5).

Reassemble and check adjustment.

Auxllletry Fuses

Refer to Fig. 15.

On breakers with "A" and "C" suffixes, a set of pro

tecting fuses (4) are mounted on the front of the breaker. These fuses

will be the primary protection devices for the closing control circuits
on those breakers that are used In metal-clad units designed for sole
noid operated breakers.
Inspection and Test

1. For ease In reviewing the adjustments, the following are recapitulated:

a. Primary contact wipe: 5/16"+ 0 - l/l6".

b. Arcing contact wipe: 5/i6" or greater (gap at primary contacts).
c. Primary contact gap: 5-1/4"+ 5/l6" - 1/8".
d. Trip latch wipe: 3/l6" to 1/4" with trip latch resting against
stop pin.

e. Trip latch clearance: 1/32" to l/l6".
f. Prop clearance: l/l6" to 5/32".

QEI-88764

g. Release latch wipe: 3/16" to 1/4".
h. Release latch monitoring switch: maximum clearance 1/32".

1. Motor and relay switch: maximum clearance 1/32",
J. Interlock switch: maximum clearance 1/32".

k. Auxiliary switch "a" contacts close when breaker primary contact
gap Is 1" or greater.
1. Driving and Latching Pawl:

minimum clearance to ratchet teeth

.015".
m. Latch checking switch contacts make when the gap between the trip

latch and the stop pin Is I/16".
n. Plunger Interlock: 10-7/32" plus or minus I/I6".
o. Auxiliary switch linkage: 12-1/4" ("A" breakers only).
2. Check all nutSj washers, bolts, cotter pins, and terminal connec
tions for tightness.

3. Inspect all wiring to make sure that no damage has resulted during
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.

3. 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.

6. See that any place where the surface of the paint has been danuiged
is repainted Immediately.

7. Check the trip coll plunger and the release coll 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. This represents 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.

The opening speed of the arcing contact should be a minimum of 13 feet

per second.

This represents the average speed over 3" from the point

when the tip on the movable contact Is tangent to the lower surface of
the upper x*unner.
Control Power Check

After the mechanism has been closed and opened slowly several times with
the maintenance closing wrench and the mechanism adjustments are checked
as described, the operating voltages should be checked at the release
coll, trip coll, and motor termlnsas. For electrical operation of the
mechanism, the control power rasiy be either an alternating or direct current source. The operating ranges for the closing and tripping voltages
are given on the breaker nameplate. The following ranges are ateuidard:
11

250v d-c
115v a-c
230v a-c

50v
115V
130v
230v
260v
125v
250V

d-c
d-c
d-c
d-c
d-c
a-c
a-c

60v
125v
l40v
25OV
28OV
125v
25OV

d-c
d-c
d-c
d-c
d-c
a-c
a-c

If the closed circuit volteige at the terminals of the coil or motor does

not fall in the specified range^ check the voltage at the source of pow
er and line drop between the power source £Uid breaker.
When two or more breakers operating from the same control power source
are required to close simultemeously^ 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 merely 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 (11) Fig. 2 or
the manual close button (7).

Before the breaker is finally raised into position in the metal-clad
unit, rub a small amount of Q-E contact lubricant D50H47 on the silver

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

GENERAL MAINTENANCE

Dependable service emd seifer power equipment eire contingent upon the
unfeULling performance of the power circuit breaker. To m£d.ntain such
service, it is recommended that a definite inspection and maintenance
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 lubrication of parts subject to wear is also viteilly im
portant for the successful operation of the breaker.

oei-8876%

—^
^ ^

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 MECHANISM WHILE IN
THE CIOSED POSITION UNLESS THE PROP AND TRIP LATCH HAVE BEEN SECURELY
WIRED OR BLOCKED TO PREVENT ACCIDENTAL TRIPPING. DO NOT WORK ON THE
BREAKER OR MECHANISM WHILE THE SPRINGS ARE CHARGED UNLESS THEY ARE
SECURED IN THAT POSITION BY THE MAINTENANCE SPRING BLOCKING DEVICE.
Periodic Inspection

The frequency of periodic Inspection should be determined by each

operating compsiny on the basis of the niMber of operations (including
switching), the magnitude of currents Interrupted, and any unusual
operations which occur from time to time. Operating ejiperlence will
soon establish a maintenance schedule which will give assurance of
proper breaker condition.
On Installations where a combination of
fault duty and repetitive operation Is encountered, an Inspection Is
recommended after any severe fault operation. The following Instruc
tions list the main points to be Included In an Inspection and, a num
ber of general recommendations.
Arc Chutes

It Is not necessary to Inspect the arc chutes unless there Is evidence
of damage or If the arc chutes are removed for any reason. When In
specting 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.
2. Cracks which have formed In the fins of the arc chute are to be ex

pected 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 arc chute has suffered any mechanical Injury due to dropping
or accidental striking, resulting In the actual breeddng off of fins,
replacement of the chute will be necessary. Small broken comers on
the exhaust end of the chute will not Interfere with Its performance
and can also be disregarded.

4. The plastlsol flexible covering for the pole pieces (3 & 4) Pig. l6
and the upper mounting support (13) Fig* l6 should be Inspected for
breaks In the Insulation.

If there are holes or breaks In the In

sulation they should be reped.red or the part replaced.
Arc Chute Removal

The arc chutes of the 13*8 KY breakers require a mechanical aid to re
move and replace them at general maintenance periods. This can be
accomplished by an overhead crane, a portable hoist, or by an arc
chute lifter especially designed for this purpose.

GEI-88764

The Arc Chute Lifter (l6) Pig. 19 holts on the top plate of the breaker,
in line with the chute to be removed, and will lift, transport, and re- '
lease the chute as necesseu*y.
To use the Arc Chute Lifter proceed as follows:

1. Remove box barrier (2) Pig. 7.
2. Remove one bolt (13) Fig. 19 from the top plate of the breaker on
the pole that the arc chute is to be removed.

3* Place the arc chute lifter over the reeir bushing and replace bolt.

4. Lower grappling hooks (17) by turning handle (14) clockwise until
hooks can be placed over lifting bolts (l8) in arc chute.

3. Turn handle counter clockwise until hooks begin to lift arc chute.

6. Loosen the two upper supporting bolts ( 2) Pig. 19 and the one lower
supporting bolt (9 ) Fig. 19 using a 3/4" wrench.
7* Tiu?n handle of arc chute lifter coimter clockwise and move chute

gently from side to side until both upper and lower supports are
clear.

8. Move trolly (15) Fig. 19 of the arc chute lifter to the rear.
9. Turn handle of arc chute lifter clockwise until arc chute is rest
ing on the floor and hooks can be removed.
Breaker Contacts

removing the box barrier the movable and stationary primary contacts

and the movable arcing contacts can be inspected. The stationary arc
ing contacts can be inspected only after removing the arc chute assembly, as e3q)lained under REPAIR AND REPLACEMENT.

If the contacts are

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

After completing infection of the contacts, check the contact adjust
ments as specified under 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 inspected for any evidence of danuige or excessive wear. Lubricate

the mechanism as outlined below, then, using the manual cheu?ging wrench,
open and close the breaker several times to make certain that the mecha

nism operates freely l^oughout its entire stroke. Check the mechanism
adjustments as specified under ADJUSTMENTS. Check all terminal connec
tions.

Bushings and Insulation

The surface of the bushings should be kept clean and unmarred to pre
vent moisture absorption.

If the insiilation surface should become

damaged, it should be sanded and cleaned, and should be refinished

with either clear va3?nish or clear resin.

Allow to dry smooth and hard.

GEI-88764

All other Insulation parts on the breaker should be kept clean £ind dry.
Smoke or dust collected between inspection periods should be wiped off,
and If dampness Is apparent, heaters should be Installed to Insure dryness.

Insulation Test

When Insulation has been repaired or replaced, or when 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 27,000 volts BMS will normally Indicate whether
the breaker Is satisfactory for service. With the breaker contacts In
the fully open position, apply the high potential to each terminal of
the breaker Individually for one minute with all other terminals suid
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 have been affected by moisture absorption.
If the breaker secondary wiring Is to be given a hl-potentlal test at
1500 volts, remove both of the motor leads from the terminal boards.
Failure to disconnect the motor from the circuit may cause damage to
the winding Insulation,
LUBRICATION

In order to maintain reliable operation. It Is Important that all clr-

cult breakers be properly lubricated at all times.

Most of the bear

ings and rolling surfaces utilize a new type of dry lubrication that
will require no maintenance and will last the life of the equipment.
Only few bearings and surfaces listed In the chart. Pig. 20, 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 evidenced by hardening and darkening In color.

Elimination of the

hardened lubricant Is essential for the proper operation of circuit

breakers.

Also frequent operation of the breaker causes the lubricant

to be forced out from between the bearing surfaces.

A simple lubrica

tion will often clear up minor disturbances which might be mistaken
for more serious trouble.

A definite lubrication schedule should be set up taking Into considera

tion 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 chstrt. Pig. 20. It Is eilso recommended
that all circuit breakers be operated at regular Intervsils to Insure
the user that the equipment Is operating freely.

GEI-88764

The lubrication chart. Pig. 20, is divided into two methods of lubri
cation.

The first method outlines the maintenance lubrication which

should be performed at the time of periodic maintenance, and requires
no 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 rea
sons, or if the operation of the breaker becomes slower.

General Electric Lubricants D50H15 and D50H47 are available in 1/4"*^
collapsible tubes.

It is so packaged to insure cleanliness and to pre

vent oxidation.

Method of Cleaning Bearings

Whenever cleaning is required, as indicated in the lubrication chart,
the following procedures are recommended:
Sleeve Bearings

The sleeve bearings used throiaghout the linkage utilize Teflon surfaces
and do not require lubrication. 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 contaminates, such as dry or hardened grease.
If contaminants are present they should be removed by immersing the link
and bearing in clean petroleum solvent or similar cleaner and using a
stiff brush. Do not remove the bearings from the links. DO NOT USE CAR
BON TETRACHLORIDE.

The hinge of the primary contact arm (24) Pig. 7 should be disassembled,
cleaned, and lubricated with G-E D50H47 lubricant at general overhaul
periods.

The main shaft bearings (24) Pig. 5 and the driving pawl lever bearing
should be removed, cleaned, and lubricated with G-E D50H15 lubricant
at general overhaul periods.
Roller & Needle Bearings

The cam follower bearings (6) Pig. 5, latch roller bearing (9)* and cam
shaft be6u»ings (25) Pig. 5 should be first removed from the mechanism
and the inner race disassembled. They shotild then be placed in a con
tainer of clean petroleum solvent or similar cleaner. DO NOT USE CARBON
TETROCHIDRIDE. If 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 be£u?ings in the cleaning solu

tion, and using a stiff brush to remove the solid particles, the bear
ings can be satisfactorily cleaned. Do not handle the bearings with
beire hands as deposits from the skin onto the bearings are inductive to
corrosion. If the bearings are touched, the contamination can be re
moved by washing in alcohol. After the bearings have been thoroughly
cleaned, spin them in clean new light machine oil luitil the cleaner or

aEI-88764
solvent is entirely removed. Allow this oil to drain off and then re
pack them immediately with G-E lubricant D30H15 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 sQcohol is perfectly clean, and do not allont the
bearings to remain in the alcohol more than a few hours.
If i t is desir
able to leave the bearings in the alcohol for a longer time, an inhibit
ed alcohol such as i s used for anti-freeze should be used.

Even then

the bearings should be removed from the alcohol within twenty-four hours.
Esso Anti-Freeze 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
room; excessive exposure to the fumes is sometimes unpleasant to person
nel. Washing the bearings in the light oil and draining should follow
immediately, then apply the lubricant.

Bearings that are pressed into the frame or other members such as the

eccentric drive bearings (7) Fig. 15 should not be removed.

After re

moving the shaft and inner race the bearing can usually be cleaned
satisfactorily with petroleum solvent or a similar cleaner and a stiff
brush. Follow the procedure outlined above using a light machine oil
and Q-E lubricant I15OHI3 before reassembling the inner race and shaft.
Rolling Surfaces

A number of rolling and rubbing surfaces in the mechanism have been
lubricated with a baked-on, dry, molybdenum disulfide coating. This
requires no msiintenance and should last the life of the breaker.

RECOMMENDED MAINTENANCE PGR MAGNE-BLAST BREAKERS APPLIED TO REP^ITIVE
swMCHim Dtmr:

1. Magne-blast breakers applied to repetitive operation such as switch
ing arc furnaces and motors should be serviced and maintained ac
cording to the following schedule:

A. Every 2000 Operations, or Every Six Months - Whichever Comes First
1. Remove the box barriers.

2. Wipe all insulating pai»ts clean of smoke deposit and dust with
a clean dry cloth, including the bushings, and the inside of
the box barriers.

3. All areas in the threat area of the arc chute should be thor

oughly cleaned by using sandpaper. This cleaning should be
performed any time the arc chute is removed. The arc chute

fins should not be cleaned. Whenever the arc chute is removed,
loose dust and dirt should be blown out before replacing arc
chutes.

aBI-88764

4. Primary Contacts - Inspect the condition of the stationary con-

tact fingers and movable contact blocks.

Badly pitted or biorn-

ed contacts should be replaced. (Note: Burned primary contacts
indicate the probable need for arcing contact replacement). If
the contact surfaces are only roughened or galled^ they should
be smoothed with crocus cloth or draw filed.

After contact

dressing the primary contacts should be greased lightly with
D50H47.
5. Arcing Contacts - Vfhen the arcing contact wipe is less than the
minimum specified under ADJUSTMENTS, the contacts should be re

placed.

The contacts should be inspected for uneven weeu? and/

or dametge using a mirror to inspect the stationary contacts.
Noi*mally i t will not be necessary to remove the arc chutes for

this 2000 operation servicing unless inadequate wipe or contact
condition indicate a need for replacement. When the aro chutes
are removed, the contact braids, coil protectors, and other

parts subject to arcing should be checked for possible cleaning
or replacement.

Do not grease the arcing contacts under any

circximstances.

6. Check the breaker and mechanism adjustments as summeu^ized under
INSPECTION AND TEST.

The necessary readjustments should be

made as described under ADJUSTMENTS.

7. The breaker and operating mechanism 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 contact support should be inspected for possible

need of replacement.

8. The contacts of the control relay should be inspected for wear
suid cleaned if necessary.

9. Lubricate the breaker operating mechanism in accordance with
the table under LUBRICATION.

10. Inspect all wiring for tightness of connections and possible
damage to insulation.

11. After the breaker has been serviced, it should be slowly closed
and opened, as described in INSTALLATION, to be sure there is
no binding or friction and that the breaker contacts can move
to the fully opened and fully closed positions. Its electrical
operation should then be checked using either the test cabinet

or the test couplers.

^
^

GEI-88764

B. After Every 10,000 Operations
1. In addition to the servicing done each 2,000 operations, the

^c chutes sho^d be removed from the breaker and disassembled
to permit a detailed inspection of insulation, blow-out coils,

arc rulers and assemblies which can become contaminated by sire
products.

2. The blow-out coils should be carefully examined and if the in
sulation has been cracked, shrunk or eroded from arc action and
heat so that the turns of the coils are not fully insulated
from each other, the coils should be replaced.
should be checked for tightness.

All connections

3* 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.

4. Check the stationary arc contacts to assure that the arcing con

tacts are in good condition and that their connections are tight.

5« Insulating material that is carbonized and cannot be satisfactor
ily cleaned should be replaced.

6. Any parts damaged or severely burned and/or eroded from arc ac
tion should be replaced.

NOTE: Pine cracks may develop in the fins of the arc chute
sides. This is to be expected with ceramic materials when sub

jected 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. Small broken corners on the exhaust end of the
arc chute will not interfere with its performance and can also
be disregarded.

7. 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 replaced when reduced in
thickness to less than 1/32".

C. Every 20,000 Operations or Approximately Every Five Years - Whichever comes p i r s t .

—

1. At this time the breaker should be given a general overhaul and
all excessively worn parts in both the mechanism and breaker re
placed. Such wear will usually be indicated when the breaker
cannot be adjusted to instruction book tolerances. This overhaul

and inspection is more detailed and will require disassembly of

mechanism and breaker operating parts.

OEI-88764
2. All roller and needle bearings in the operating mechanism
should be disassembled^ cleaned, and repacked with G.E. lubri
cant D5OHI3 as described under LUBRICATION.

3. The stationary primary contact fingers should be disassembled
and the silver-plated pivot area of the contact and contact

support cleaned and lubricated with G-E lubricant D30H47.

4. The breaker and operating mechanism should be serviced as des
cribed for every 2,000 operations and properly adjusted before
being put back into service.
2. Magne-blast breakers applied to repetitive operation such as capaci
tor switching should be serviced and maintained according to the
proceeding recommendations, and in addition, should have items lAl,
1A2, £Uid lk3f repeated at 300 operation intervals.
TROUBLE SHOOTING

brief outline showing particular types of distress that might be encoun
tered, together with suggestions for remedying the trouble:
Failure to Trip

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

Lubricate complete mechanism.

2. Mechanism binding or sticking caused by being out of adjustment.
RMEDY: Check all mechanism adjustments, latches, stops, auxiliary
devices, etc., in accordance with section on ADJUSTMENTS.

Examine

latch and roller surfaces for corrosion.

3. Damaged trip coil.
REMEDY: Replace damaged coil.

4. Blown fuse in trip circuit.
REMEDY:

Replace blown fuse after determining 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

Mechanism binding or sticking caused by lack of lubrication.
REMEDY: Lubricate complete mechanism.

GEI-88764
2. Damaged or dirty contacts In control circuit.
REMEDY: Recondition or replace contacts.

3. Blown fuse In closing circuit.
REMEDY: Replace blown fuse after determining cause of failure.

4. Faulty connection In charging circuit.
REMEDY: Repair broken or loose wires and see that all binding screws
are tight.
Overheating

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

REMEDY:

Recondition or replace burned and pitted contacts. (Contacts

should be reconditioned very carefully and only when absolutely neces

sary.)
2. Contacts not properly aligned or adjusted.
REMEDY: Check all adjustments In accordance with section on ADJUST
MENTS.

3. Breaker kept closed or open for too long a period.
REMEDY: Operate breaker more often to wipe contacts clean.

Replace

contacts If necessary.

4. Overloading.
REMEDY: Replace breaker with one of adequate rating for present or
future load, or re-arrange circuits so as to remove excess load.
3. Primary connections of Inadequate capacity.
REMEDY:

Increase size or number of conductors or remove excess cur

rent.

6. Loose connections or terminal connectors.
REMEDY: Tighten.

7. Ambient temperatin'e 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 InstSLllatlon on parts of the breaker that are most subject to damage or wear.
IMPORTANT:

UPON COMPLETION OF ANY REPAIR WORK, ALL BREAKER AND MECHA

NISM ADJUSTMENTS MUST BE CHECKED.

Refer to the section on INSTALLATION,

paying pau^tlcular attention to ADJUSTMENTS said FINAL INSPECTION.

OEI-88764

Arc Chute (To Inspect or replace blow-out colls)
To remove an arc chute« first open the breaker and remove the box bar

rier (2), Pig. 7.

Loosen the two upper supporting bolts (2) Pig. 19

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 Pig. 19.
To dlsetssemble the arc chute after I t has been removed from the breaker,
proceed as follows:

1. Remove the assembly bolts (2,6,7,9^10,12, and 15)» Pig* 16.
2. Remove the side brace (l4), and rear brace (5), the upper pole
pieces (3)« and the lower pole pieces (4), Pig. l6.
3. To remove the upper mounting support (13)* Fig. l6 remove the assem
bly bolts (1 and 11), and the upper connection bolt.

4. Remove the assembly bolt (l8) to remove the lower brace (8) Pig. l6.
5. Remove the lower mounting support (l6) by removing the assembly
bolts (17) Pig. l6 and the connection nut (7), Fig. 18.

6. At this point, the fiber side shields (4), Pig. i8, and the upper
arc runner assembly (2) can be removed.
7. Further disassembly of both the upper and lower arc riuiner assemblies

can be done by removing the various screws and 1/4" assembly bolts

(not Illustrated) as shown In Pig. 17.

8. The arc chute sides (6) Pig. 17, can also be separated for Inspec
tion.

Reassemble the arc chute In the reverse order.

The following Items

should be noted during reassembly:

1. Equally space the fins of the arc chute sides before bolting together.

2. The gap between the fins at the rear of the arc chute should be 3/64"
to 3/32" measured at least 1" In from the back end of the arc chute
(see Pig. 21).
3. Check to Insure that electrical connections to the blowout colls are
tight.

4. Vfhen reassembling the arc runner assemblies, check that the spacers
(1 and 10), Pig. 17* are correctly Installed.

GEI-88764
'

5* 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.
6. Make certain that the electrical connections are tight.
To reassemble the arc chute to the breaker, proceed as follows:

1. Rest the lower mounting support (8) on the arc chute mounting brack
et (7) as shown in Pig. 19.
2. Slide the arc chute forward and lift i t slightly to engage the sup

porting bolts (2), Pig. 19, in the slots of the upper mounting sup
port (3).
3. Check the spring baffle (11), Pig. 22, to assure that it closes the
gap between upper insulation (19)*
16 and the back of the con
tact support (4), Pig. 22.
4. Tighten the supporting bolts (2 and 9) Pig. 19.

These bolts serve

as both the electrical and mechanical connections between the bush
ing and the arc runners.

5. Check that the movable arcing contact (4), Pig. 19* passes between
the probes on the upper arc runner (5) Pig. 17 without touching.
Contacts

Open the breaker and remove the box barrier and arc chutes as previous
ly described.

To remove the contacts, proceed as follows:

A. Stationary Arcing Contacts (10)« Pig. 22.
1. Disconnect the contact braids from the contact fingers by remov

ing two bolts (8), Pig. 22.

2. 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.

GEI-88764

B. Stationary PrimgLcy 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 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. Apply a thin coating of D50H47 grease on the hinged edge of the

finger (9) then place it on the contact support (7) so that it
is retained by stop plate (8).

2. Open spring compressor (3) and assemble spring guidej spring and
spring con?)ressor (Pig. 23A).
3. Turn nut (2) in clockwise direction to compress contact spring
(Fig. 23B). Hold spring firmly in yoke on spring compressor to
prevent 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 cutout in primary finger (Pig. 23C).
5. Hold spring assembly firmly in place and remove spring compressor.

C. Movable Arcing Contact (7), Pig. 24

1. Remove the assembly bolts (8).
2. Reassemble in reverse order.

D. Movable Primary Contacts (5), Pig. 24 (1200 Amp. Breaker)
1. Remove the nuts from assembly bolts (6).
2. Remove the primary contacts.
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).

GEI-88764

4»

the contact arms (4) and remove the primary contacts (5).

5. Reassemble in the reverse order.

E. Contact Blade Assembly (4, 5, 7) Pig, 24
1, Remove the connection bar (9).

2, Remove the cup besucing (3) and the pin (11).

3. Vtfhen reassembling, first insert the piston assembly (10), into
the booster cylinder and reassemble the cup bearing (3).
4. Replace pin (ll), and connection bar (9).
F. After disassembly and reassembly of any contacts, check all contact
adjustments as described under ADJUSTMENTS.
Bushings

IMPORTANT: DO NOT REMOVE ALL SIX BUSHINGS AT ONCE. The bushings have
been carefully aligned with the breaker frame, during assembly at the
factory, and i t is important that this alignment be maintained to fa
cilitate installation of the breaker in 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 particuleu* bushing to adjacent bushings in both direc
tions, so that i t may be reinstalled 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 metal-clad unit before
tightening the bushing moimting bolts. This must be done before the
arc chutes are reinstalled.

To replace the bushing, proceed as follows:
Rear Bushing

1. Open the breaker and remove the box barrier and arc chutes as al
ready described.

2. Remove the upper and lower horizontal barriers (l4 and 18), Pig. 7.
3. Remove the four bolts at the mounting flange of the rear bushing
being removed and lower the bushing assembly.

4. Referring to Pig. 23, disassemble the primary contact springs (6)
as previously described.

5. Disassemble the spring retainer (4) by removing mounting bolts (5)*

GEI-88764

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 bracket (2)

is not symmetrical and must be assembled correctly to orient the
chute properly on the breaker. The longest projection of the brack
et should be toweird the lower end of the bushing.
Front Bushing

1. Open the breaker and remove the box barrier and etrc chutes as al
ready described.

2. Remove the upper and lower horizontal barriers (l8 and 20) Pig. 7.

3. Remove the connection beu* (9)> Pig. 24, cup bearing (3), and pin
(11).

4. Remove the four bolts at the mounting flange of the front bushing
being removed, and lower the bushing.

5. Vfhen reassembling, first mount the bushing and assemble the cup

bearing (3) contact arm (4), and replace pin (11).

The contact sur

faces at the hinge point of the contact blade and bushing should
have a thin coating of D50H47 grease.

6. Check all contact adjustments as outlined under ADJUSTMENTS.
INTERLOCK SWITCH

To remove the interlock switch (3), Pig. 10 remove the two mounting
screws and disconnect the lead wires.

Reassemble in the reverse order

and check the switch adjustments as explained under ADJUSTMENTS.
LATCH CHECKING SWITCH

To remove the latch checking switch (7), Pig. 10 (when furnished), re
move the two mounting screws eind disconnect the lead wires.

Reassemble

in the reverse order and check the switch adjustments as explained un
der ADJUSTMENTS.
MOTOR. RELAY AND LIGHT SWITCHES

The three switches are mounted in tandem as shown in Pig. 6.
1. Remove the opening spring per instructions below.

2. Remove (2) mounting bolts (l4) from switch bracket (15).
3. Remove the (2) mounting screws of the lower switch.
4. Remove the (2) mounting screws of the center switch.

GEI-88764

5« Remove the (2) mounting screws of the upper switch.
6. Disconnect the lead wires of switch to be replaced.
7* Reassemble In the reverse order and check switch adjustment as
e:q}lalned under ADJUSTMENTS.
TRIP SHAFT AND LATCH

1. Remove latch checking switch arm (10) Fig. 11 (when supplied).
2. Remove cotter pins on both ends of the sheift (12).

3. Remove set screw In latch (ll).
4. Remove trip coll linkage bolt (6).

5. Place a block between the latch and frame (either side) and
drive shaft xantll the latch Is free of the key.

6. Remove key and all burrs that may be raised around the keyway on the
shaft.

Burrs will scar or shave the Teflon bearing surfaces If they

are not removed.

7. Reassemble the parts In the reverse order. Be sure the latch spring
Is properly Installed and the latch Is aligned In the center of the
latch roller. Check latch adjustment as described under ADJUSTMENTS.
TRIP LATCH ROLLER BEARING

1. Remove (2) cotter pins at ends of shaft (8) Fig. 12.
2. Partially remove shaft out right side of frame until latch roller
(6) Is free.
3. Reassemble In reverse order with proper spacing of washers.

Be sure

latch roller rotates freely.
CLOSING LATCH

1. Remove cotter pins at both ends of latch shaft (19) Pig. 6.
2. Remove spring and paddle (l6) Fig. 6.
3. Remove set screws from latch (3) Pig. 6.

4. Move shaft (14) to left (away from frame) by tapping lightly on the
Inside end of shaft. Rotate shaft and continue tapping until shaft
Is free. Shaft will push outside needle bearing from housing.

qei-88764

5. Reassemble in reverse order putting bearing into frame last. Use a
small piece of tubing or pipe when inserting bearing to assure pro
per alignment.

6. Check latch adjustments as described under ADJUSTMENTS.
MOTOR SUPPORT

1. To remove motor support (8) Pig. 15> first remove the latch spring
(16) Pig. 6.

2. Remove the retaining ring (9) Pig. 15 and link (10).
3. Remove motor leads from the terminal board.

4. Remove six 3/8" bolts (l) Pig. 15 on bottom and one 3/8" bolt on
the right side (not shown).
5. Remove four mounting bolts from motor (not shown).

6. Remove the retaining ring (7) from the eccentric (2) Pig. 15.
7. Reassemble all parts of the motor support in the reverse order and
re-align i t properly as described under DRIVINO PAWL ADJUSTMENTS.
CAM

1. Remove 2 set screws from ratchet wheel (3) Pig. 3 and remove wheel
from main shaft (8).
2. Remove 2 set screws from cam (12) Pig. 1.

3. Remove prop reset spring (10) Pig. 2.
4. Remove 2 set screws from cam .(16)^ Pig. 5t 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.

5. Remove shaft out left side of frame.

6. Reassemble in reverse order using the correct number of washers and
spacers to properly locate thd parts.

7. Rotate the mechanism through a closing operation using the msuiual

charging wrench. Check the location of the cam follower (6), Pig.
5> on the cam (l6). If necessary^ move the cam to correct the
alignment.

Complete the closing operation and check the location

of the prop pin (13)* Pig. 5 on the prop (l4).
proximately centered.

It should be ap

aBI-88764
TRIP COIL

To replace the potential trip coil (2)^ Fig. 11 proceed as follows:
1. With the breaker in the open position^ remove the two mounting bolts

(3).
2. Remove upper support (1) and spacers.
3. Cut wires at the butt connectors and remove coil.

4. When replacing the coil be sure to assemble the correct fiber spa
cers at the ends before bolting support (l).

3. Adjust coil location to allow approximately 1/4" of eunoature travel
before latch starts to move.

6. Butt connect wires and check operation of solenoid electrically and
mechanically.
SPRING REDBASE COIL

To remove the spring release coil (3) Fig* 6 proceed as follows:
1. Block the closing springs as described in INSTALLATION.

2. Remove the left hand closing spring as described in CLOSING SPRINGS
below.

3. Remove two mounting bolts (17)> coll support (18), and spacers.
4. Cut wires at the butt connectors and remove coll.

3. Replace the coil and the correct number of fiber spacers before
bolting support.

6. Butt connect wires and check that the armature is not binding.
Check coil for electrical operation.
CLOSING SPRINGS

The closing springs (6) Pig. 3 can be removed as follower
1. Charge the springs with the manual charging wrench and apply the
spring blocld.ng device as described in INSTALLATION.

2. Discharge springs by pushing mauiusQ. close button (7) Fig. 2.

GEI-88764

3. Rotate cam shaft (8) Fig. 3 ty using the manual chsu*glng wrench un
til the gap between the spring (6) and the bearing block (10) Is 2
Inches or more.

4. Lift both springs until they clear the lower supports, then pull
forward and down until the top supports are free.

5. Either discharge the opening springs by pushing the manual trip
lever or block the opening springs with a suitable blocking device.
OPENING SPRINGS

To remove the opening springs (9) Elg. 3 proceed as follows:
1. Charge and block the closing springs as described under INSTALLATION.

2. Push manual trip lever (11) Pig. 2 to be sure the opening springs
are fully discharged.

3. Remove upper pin (12) Fig. 3 and lower pin (11).
4. After reassembling springs check the primary opening as described
under PRIMARY CONTACT GAP.
RENEWAL PARTS

It Is recommended that sufficient renewal parts be carried In stock to

enable the prompt replacement of euiy worn, broken, or damaged parts.
A stock of such parts minimize service Interruptions caused by break
downs, and saves time and expense. When continuous operation Is a
primary consideration, 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 ln5>rovements are made from time to time. The parts which
are furnished, however, will be Interchangeable.

The Renewal Parts list covers the following types of breakers:

AM-13.8-500-5A
AM-13.8-500-5AR
AM-13.8-500-5AB
AM-13.8-500-5ABR
AM-13.8-500-5C

1200A
1200A
1200A
1200A
1200A

&
&
&
&
&

AM-13.8-500-5CR
AM-13.8-500-5CB
AM-13.8-500-5CBR
AM-13.8-500-5H
AM-13.8-500-5HR
AM-13.8-500-5HB
AM-13.8-500-5HBR

1200A
1200A
1200A
1200A
1200A
1200A
1200A

&
&
&
&
&
&
&

2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A

OEI-88764

NOTE:

The listed terms "Right" and "Left" apply when facing the mecha
nism end of the breaker.

ORDERING INSTRUCTIONS

1. Always specify the complete nameplate data of both the breaker and
the mechanism.

2. l^ecify the quantity, catalog number (if listed), reference nuiii'oer
(if listed), and description of each part ordered, and this bulle
tin number.

3. Standard hardware, such as screws, bolts, nuts, washers, etc., is
not listed in this bulletin. Such items should be purchased lo
cally.

4. For prices, refer to the nearest office of the General Electric
Company.

GEI-88764

PARTS RECOMMENDED FOR NORMAL MAINTENANCE

In the tabulation below are listed the parts of those bresdcers which are
usually recoRuaended for stock for normal maintenance.
Fig.

263B292
281B708
2360791
2360791
2360790

P-2
G-1
G-1
G-4
G-9

3
3
3
3
3

12
12
12
12
1

All
All
1200
2000
1200

All

4i4aii6 P-4

All
All
All

6445087 P-4
6557243 P-1
6557243 P-2

1200
2000
All
All
All
All
1200
2000
1200
2000
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

2360791 P-8
2360791 P-8
4i4a194 p-2

456A336 P-1
802B742 G-3
137A9164 P-3
137A9164 P-3
137A9164 P-4
137A9164 P-4
2650163 P-2
802B735 P-1

24
6
3
6
3

i
3
6
6
6
6

421A201 P-1
10509393 P-1
10509393 P-2
10509393 P-3
10509393 P-2
10509393 P-3

137A7575
137A7575
137A7575
137A7575
137A7575

P-43
P-42
P-41
P-47
P-45

Booster Cylinder
Operating Rod Assembly

Flexible Connector fLeft)

Flexible Connector (Right)
Stationary Arcing Contact
Assembly
Insulating Plate

Buffer

Clamp for Buffer
Clamp for Buffer
Primary Contact Finger
Spring

Primary Contact Finger
Spring
Primary Contact Finger
Spring
Primary Contact Finger
Primary Contact Finger
Upper Shield
Insulating Plate
Lower Shield

Movable Arcing Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Upper Runner Insulation
Lower Runner Insulation
Lower Shield

Motor 48 VDC
Motor 110 VDC
Motor 220 VDC

125 VDC
250 VDC

Motor 115 VAC
Motor 230 VAC
1

Relay 48 VDC

lA
lA
lA

Relay
Relay
Relay
Relay

6275070 G-1
6275070 0-2

Trip Coil - 24 VDC
Gpring Release & Trip Coil
48 VDC
Gpring Release & Trip Coil
110 VDC

Spring Release & Trip Coil
125 VDC

All

6174582 G-15

Spring Release & Trip Coil

Spring Release & Trip Coil
250 VDC
Spring Release & Trip Coil

All

6174582 G-14

All
All
All
All
All
All

All
All
All
All
All

456A866 P-5
456A866 P-6

All

220 VDC

115 VAC

Spring Release & Trip Coil

137A9252

1
1
1
1

230 VAC
Switch Normally Open
Switch Normally Closed
Auxiliary Switch
Closing Latch Spx'lng
Prop ^ring

Check connection diagram for (l) or (2) relay requirements,

4; (1) required for spring release and (l) required for tripping.
May be different voltages - check nameplate for requirements.

All except breakers with "B" in suffix.

Right Side View ML-13

1. Latching Pawls
2.

Positive Interlock Roller

Fig. 4

Spring Blocking Device

Close Button
Motor
Fuse

3. Ratchet Wheel
4. Eccentric
5. Fuse

Driving Pawl

6. Closing Spring

Eccentric

7. Main Shaft Bearing
8. Cam Shaft
9. Opening Spring

Closing Spring
Manual Charging Wrench
Support Bolts
Charge-Discharge Indicator

10.

Guide Block

11. Lower Spring Pin
12. Upper Spring Pin

Spring Blocking Device

€

11405320

Fig. 5

Sectional Side View of Mechanism

1. Handle
2. Trip Coil Support

i:
I:
I:
5
6

Trip Coil
Trip Armature
Prop Reset Spz*ing
Cam Follower Roller

Trip Shaft
Trip Latch
9. Trip Latch Roller

10. Trip Latch Roller
11. Crank Shaft

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

1. Stationary Primary Contacts
2. Movable Primary Contacts
3. Biiffer Block

4. Stationary Arcing
Contacts

5. Movable Arcing Contacts
6. Contact Arm

GEI-88764

•

Fig. 7

Cross Section of Breaker Pole Unit

1. Box Barrier Catch
2. Box Barrier

3. Arc Chute

4. Arc Runner, Upper
5. Blow Out Coil, Upper

6. Blow Out Core, Upper
7. Movable Arcing Contact

8. Arc Runner, Lower
9. Blow Out Coil, Lower
10. Blow Out Core, Lower
11.

Pole Pieces

12. Front Bushing
13. Rear Bushing

14. Upper Horizontal Barrier
15. Main Operating Crank

16', Arc Chute Support
17.
18.
1920.
21.
22.
23.

Spring Retainer
Lower Horizontal Barrier
Operating Rod
Stationary Arcing Contact
Stationary Primary Contact
Movable Primary Contact
Movable Contact Arm Assembly

25.
26.
27.
28.
29.

Booster Tube and Piston
Front Vertical Barrier
Check Nut
Connection Bar
Booster Cylinder

24. Cup Bearing

GEI-88764

jri
Fig. 9
Adjustable Coupling for Making
Primary Contact Wipe Adjustments

1. Operating Rod
2. Operating Rod Pin
3. Adjusting Nut
4. Check Nut

Pig. 10

5. Stationary Primary Contacts
6. Movable Primary Contacts
7. Contact Arm
8. Yoke

Positive Interlock Switch

i. Positive Interlock Shaft

6. Switch Support

7. Latch Checking Switch
8. Switch Arm
9. Trip Shaft

Switch Arm

3. Interlock Switch

4. Switch Support
5. Auxiliary Switch

GEI-88764

Trip Coil Support
Trip Coil
ffounting Bolts
Counter

Trip Latch
Trip Am Screw
Manual Trip Lever
Open-Close Indicator
Auxiliary Switch
Switch Am

Latch Set Screw
Cotter Pin

Prop Spring

Fig. 11

Auxiliary Switch and
Trip Coil

1. Switch Support
2. Latch Checking Switch
3. Switch Am

4. Trip Latch
5.
6.
7.
8.

Reset
latch
Latch
latch

Pin Stop
Roller
Roller Link
Roller Pin

Fig. 12

Latch Checking
Switch

GEI-88764

QJl
1. Plunger Bolt
2.

Washer

3. Breaker Lifting Rail

Pig. 13

Plunger Interlock

Pig. 14

Auxiliary Switch Pork

1. Front Primary Bushing

3. Hex Charging Stud
4.

Fuse

5. Manual Close Button

6. Motor
7. Retaining Ring

8. Motor Support
9. Retaining Ring

10. Driving Link

Assembly Bolts
Assembly Bolt
Upper Pole Pieces
Lower Pole Pieces
Rear Brace

Assembly Bolt
Assembly Bolt
Lower Brace

Assembly Bolts
Assembly Bolts
Assembly Bolt
Assembly Bolts
Upper Mounting Support
Side Brace

Assembly Bolts
Lower Mounting Support
Assembly Bolts
Assembly Bolt

1. I^per Arc Runner Spacers

2. Upper Arc Runner Assembly
3. Blowout Core
4. Blowout Coll
5. l^per Arc Runner
6. Arc Chute Side

7. Upper Insulation
8. Lower Arc Runner

9. Lower Arc Runner Assembly
10. Lower Arc Runner Spacers
11. Lower Coil Connection
12. Lower Insulation

Pig. 17

Arc Chute Assembly

With Side Removed

1. I^per Mounting Support
2. Upper Arc Runner Assembly
3. Upper Arc Runner
4.

Side Shield

5. Lower Arc Runner Assembly
6. Lower Coil Connection

Arc Chute Partially Removed Showing

Accessibility of Arcing Contacts
Rear Bushing
Supporting Bolt
Upper Arc Chute Support
Movable Arcing Contact
Mounting Bolts
Arc Chute Brace

Support Bracket
Lower Arc Chute Support
Lower Supporting Bolt
Upper Horizontal Barriers
Lower Horizontal Barriers

Stationary Arcing Contacts
Arc Chute Lifter Bolt
Handle

Trolly
Arc Chute Lifter

Grappling Hooks
Lifting Bolt
Arc Chute

Fig. 21

Arc Chute Fin Spacing

GEI-88764

PART

Sleeve Bearings - links«

trip shaft, etc. (Teflon
coated hearings)

LUBRICATION AT
MAINTENANCE
PERIOD

ALTERNATE LUBRICATION

No lubrication

No lubrication required.

(RE(iUIRES DISASSEMBLY)

required.

Sleeve Bearings - main crank
shaft, driving pawl lever.

Light applica

(Bronze or cast Iron)

oil SAE 20 or

tion of machine

SAE 30.

Contact Arm Hinge AssemblyCup Bearing
Loose rings between bushing

No lubrication

Remove bearings or
links, clean per In
structions and apply
D5OHI5 lubricant liber
ally.
Wipe clean and apply

Roller and Needle Bearings

tion of machine

Clean per Instructions
and repack with D5OHI5
lubricant.

oil SAE 20 or

SAE 30.

No lubrication

Ground surfaces such as

No lubrication required.

required.

cams, ratchet teeth, etc.

(Surfaces coated with M0S2)

Ground surfaces such as

latches, rollers, prop, etc.

Wipe clean and
apply D5OHI5

Wipe clean and apply
D5OHI5 lubricant.

lubricant.

Silver plated contacts and
primary disconnect studs.

Method of Installing Primary Contact Springs
Using a Spring Compressor

Spring Guide
Con^ressor Nut
3. Spring Compressor
4. Spring Retainer
5. Assembly Bolts
1.

6. Spring
7. Contact Support

8. Stop Plate
9. Stationary Primary
Finger

Rear Bushing Assembly

1. Rear Bushing
2. Guide and Support for Arc

Pig. 24

1. Contact Springs
2. Stationary Primary
Contacts

Chute

3. Bolts for Contact Support

4. Contact Support
5. Bolt for Flexible Braid

6. Mounting Bolt
7. Flexible Braid
8. Connection Bolt
9. Stud for Mounting Arcing
Fingers
10. Stationary Arcing Contact
Assembly
11. Spring Baffle
12. Insulating Plate

Removal of Contacts

3. Cup Bearing
4. Contact Arm
5. Movable Primary Contacts

6.
7.
8.
9.

Assembly Bolts
Movable Arcing Contact
Assembly Bolts

Connection Bar
10. Piston Assembly
11. Hinge Pin
12.

Buffer

GEZ*2500K

GENERAL ELECTRIC SALES OFFICES
READY TO ASSIST YOU . . . Whm Yew Kov* El»ctrical Probltms

OHIO

LOUISIANA

SAIES OTFICE CODE KEY

* Induitriel Eqwipment (inclwdlftg Agent and

* t I i Now Orloont 70112 .
* t
Shrovoport 71101 ....

•
Mebilt 34402
ARIZONA

• I I I Denver (0204 .

112S Wilihire Blvd.
. 401 Thirteenth SI.
SS Veteroni Blvd.
2407 "J" St.

Flint 40501

•
I
• t

Grand Rapidi B..
Jockion 41201

•

Kolamoioo

• I
•

Loniing 4B111 . 501 Sank of Loniing ildg.
Saginaw 4(407
lOOB Second Notional Bank BIdg.

I Cocoa (each 12111 (Capo Canaveral Office)

. 1404 S. Calhoun St.
1750 H. Meridian St.

.410 N. Michigan St.

South (end 44401
IOWA

210 Second St., S.E.
Cedar Ropidi 52401
Davenport 52005
im State St., (ottendorf, Iowa

Dei Moinei 50110
Sioui City SI101

•

Wichita 47211

104 W. Fourteenth St.
BIO Olive SI.

Kingiport i7U2

Memphii 1BI04
Naihville 37201
i Oak Ridge

1717 W. End BIdg.
251 Main SI.. Eoit

TEXAS

(20 E. Indianapolii Avo.

KENTUCKY

• j ^ Loiinglon 4gm

Corpui Chriili 78^1

lubbock 71404
Midland

22S Wllkerton-Foiler BIdg.

San Antonio 7B204....

• t

f Salt Lake City (4110.

Raleigh 27402
(itmarck 5B50I
Forgo 5BI0I

200 S. Main SI.
IB'A Cenler St.

i Newport Newi 21401

P.O. (oi 1010. HI Moin SI.

( Celvin Avo.

II Chenango St.
425 Delaware Avo.
S70 Loiington Avo.
n Eait Avo.
ISU Jonwi St.
1001 (road St.
P.O. (01 MB

Albuquerque (7I0S.. .120 Madeira Dr., N.E,

Charlotte 20202

215 N. Stonton SI.
.... 40a W. Seventh 51.
.4211 Richmond Ave.
1102 Avenue "A"

El Poio 71101
Fort Worth 74I02.._

BIOI Stemmoni Freeway

Dallai 75222

• t

121 W. Trade $1.
(01 Summit Avo.

442 Cedar St.
101 Polk St.
.. 11(5 Colder Ave.

Abilene 71401
Amarillo 71101
(eoumont 77704

.1711 S. BIh St.

Utico I

(12 Georgia Ave.

123 Commerce St.
1101 Hannah Ave., N.W.
1420 Union Ave.

Knoirville 37121

;i
t

.....401 S. Sovenleonth St.

IU2 Elm St

Hortiion St.

101 Polmelle Slate Life BIdq.
Greenville 21402
104 W. Waihinglon SI.

•

101 N. Broadway
,....101 N. Wyoming St.

NORTH CAROLINA

.1(11 Merle Hay Rd.
520 Fierce St.

s Albany 12201
(inghamton 11102...
t
Buffalo 14202
i Now York I0022....
t ' Rochoiler 14404
• t
Syracuio 11201

...2701 Waihinglon Avo.

Fort Wayno 44(07 ..
Indianapolii 42407...

• t
t

York I7«l

SOUTH CAROLINA
• t
Columbia 21201

NEW YORK

^anivillo 47714

• I

The Oliver BIdg., Mellon So'
711 Waihinglon r3:
4 Plmburgh IS22S

I Philadelphia 11102... .1 Penn Center Ploio
Piltiburgh IS222

) i Houiton 77027

NEW JERSEY

* (

712 North I4lh St.
1001 Sloto St.
041 Oak SI.

(40 S. Conol St.
2000 N.E. Perry Ave.
4221 Eail Slate St.

Rockford 4II0S

Medford
Portland 17210 ..

• t t I ChoHenooga 17402..._

Lai Vegai

lUINOIS
•

1010 Fidelity BIdg.

Norby BIdg., Room 4
—
12 5. Slith St.

NEW HAMPSHIRE

1524 Idaho SI.

I l l Chicago 404(0
• I
Peoria 41411

Omoha 4BI02.

1170 Peorl St.
107 E. Main SI.
.. 2121 N.W. 21lh Ave.

St. Louii 41101
Billingi 51101

IDAHO

• I

Tulio 74114 . Celwmbia BIdg., 24$l E. Hit St.

NEBRASKA

1040 Peochtree Rd., N.W.

Mocon

Joplin 44002
Kantai City 44105.

• t

420 Modiion Ave.
272 E. Indianelo Ave.

Oklahoma City 71102 ..111 N. Robinion Are.

. Ills H. Atlantic Ave.

Coral Gablei 31IU

Dululh 55S02

Fergui Falli
Minneapolii 55402.
GuKport 11502
Jackton 31201

114'/, W. Court St.
2(21 Mamion Ave., S.E.
120 W. Michigan Ave.

PENNSYLVANIA
Allentown IBI02

215 Montgomery St.
?I55 So. FIrit St.

US E. Brood St.

.11 W. Monument BIdg.

i Oairlon 4$402
I Manilield 44102

117 N. Riveriido Ave., Rioito, Col.

. ...41U Woodland Are.

• t t 1 Son Franciico 14104
•
Son Joie ISI12

III Park Are.

.47 Eait Franklin SI.

• I t ) Botlon 01117
•
Springfield 01103...

IS12 N. Weit Ave.

hoi Angelei 100S4
i 1 Loi Angelei 10005 ...

Baltimore 21101
Hogentown

tlorth Lillle Reck 7T704 ..IMO E. Wothin^len

CAtlPORNIA
•
Freino 11720

77 Central SI.

MARYUND

ISSO N. Control Are.
ISI S. Tocien EIrd.

Tvcion 05714
ARKANSAS

ISI Stale SI.

Avguilo
Bongor 04402

SIS Third St.. N.W.
2421 Viclory Pk»y.

i Cleveland 44104

017 Grovier SI.
500 Natckilochei SI.

US W. Morkel SI.

Akron 44101
Canton 44701
Cincinnati 4S204 .. ..

710 Mwrror St.

Baton Rowgt 70BI$...

Diitribwtor) Seiee

I Electric Utilil* Eguipment Selee
i Marine end Oehnte Egwipment Sale*
I Component Solet Operation

, Rogviro Ordorlng Inttfuctiaat

Nt«4l Pwrthtr Informorion

, 410 Reuor Avo.
(02 S. Pork Drhro

50OI W. Brood SI.
110 S. Jelferion St.

Richmond 21210...
Roonoke 2400S ..
WASHINGTON

PoKO

024 W. Lewli St.

t ( Seattle 1(104
Spokane 11220

710 Second Avo.
Eait 1(05 Trent Ave.

WUT VIRGINIA
•
Bluefield

704 Bland St.

Charieiton 2S12B...104 MocCorkle Avo., S.E.

SIO W. College Avo.
{ Appleton
Madiien SI701.... .140 W. Waihinglon Avo.
140 W. St. Paul Ave.
t Milwaukee 51211

HAWAII: Amorkan Factari, Ltd., P.O. Box 3230, Hanehita 9(B0I

CANADA: Canadian Ganoral Boctric Company, ltd., Toranto

GENERAL ELECTRIC SERVICE SHOPS
Unto 0>E tervico
perlarmanco of your equipment. For Full Information about thoio lervicoi,
- ihopl
^ will repair,. rocondi.
.
^
contact your noaroil eorvlco iliap or lalot office.
tlon, and rebuild your electric apporatue. -The Facililiei ore available day
and•*
night, eoven dayi a w^, for work in the ibopi or on your promiiei. Latecl
'Doneloi Aircraft Service Shopi
Focto^ moriiodi end gonuiM
renowol porti are uiod to moinloin peak

WHEN YOU NEED SERVICE

Leuiiville 40201

Birmingham 1S2II, P.O. (oi 1417
7 -

Loi Angelei 10C0I
.. 4100 Stanford Avo.
'(Loi Angelei) Ontario
Ontario International Airport
Oakland 14400

1400 Wood St.

Sacramento 15BI4
Son ^anclico 14101

11 North 17th St.
101S Horrlion St.

COLORADO

Denver B0205

(Seuthington) Piantivllle

Baltimore 21210

Minneapolii S5410.
Kaniai aty 44120

Allentown IBIOl

York 17401

SnS Peacliiioe Induitriol Blvd.

Dalloi 75215
Houilon 77020

1525 Gardner Avo.
IMS Eait Road

(Now York) North (ergon. N. J
.....4001 Tonnello Avo.
Schonecfody (Inilrumenlallon Service) I2I0S

Ft. Wayne 44403
Indianapolii 22.

1711 Ediall Ave.
I74B W. Vermont St.

IOWA

(Davenport) (elfondorf

I02S State St.

KANSAS

'(StreHwr) Arkantoe City
G.E. Co.. P.O. (04 717

NORTH CAROLINA
Charlotte 2(20(..
OHIO
Cincinnati 45202...
•Cincinnati 45212

212( Thrift Road

444 W. Third St.
240 W. Mitchell Avo.
Cleveland 44125.
.4477 Eait 41Hi St.
Columbul 4nZl — — —

115

Waco St.

1202 Manor Way

-5514 Harvey Wilion Drive

P.O. (01 imriTs Aibe;;;;;;^ri^^

WASHINGTON

Soaltio 1(114
•Soottlo IBIOB

1411 W. Elitabelfi Avo.

ILLINOIS

(41 Oak St.

Philadelphia 11124.
1040 E. Erie Ave.
(Pittiburgh) Homeitead 15210.
(oi ICB, RD I, Buttermilk Hollow Rd.

5150 Third St.

5t. Loull 41110.NEW YORK

(Atlanta) Chombleo

4U E. Highland St.

Johnitown

•(Now York) Linden, H. J

„...272 E. Indianolo Ave.

OREGON
Portland 17210

(Boilon) Medford 02155
1140 Myllic Valley Parkway

MISSOURI

-..1042 E. 2Slh St.
P.O. (oi 1245

P.O. (ai 2112, 2020 W, Beaver St.

2(15 N. Robertion St.

MARYUND

MINNESOTA

FLORIDA
Jackionville 12201

(Miami) Hioloah
Tampa 11401

New Orleoni 70117.

Toledo 4140S

1100 Crittendon Drive

P,0. (ei 4110, 2I2S Eakin Rd.

KENTUCKY

AUBAMA

Spekano 11204—

WEST VIRGfNIA
Charletfon 20.

1422 Hrif Avo., 5.
220 Dawion St.

C 4121 Miulon SI.
104 MacCerklo Avo.

WISCONSIN

6CNERAI EIFCTRIC COMPAHV, PHILAOEIPHIA, PA.

Appleton 54IIO1
Midway Induilrial Area
—P.O. (01 (I, Ceunly Trunk P
Mllwaukoo 1——.140 W. St. Paul Avo.

MAGNE-BLAST CIRCUIT BREAKER
TYPES

AM-13.8-500-5C
AM-13.8-500-5CB
AM-13.8-500-5H
AM-13.8-500-5HB
AM-13.8-500-5HV
AM-13.8-500-5HVB

Receiving, Handling
and Storage
Installation.

Description of
Operation...,

.--c

Adjustments.
General Maintenance,
Renewal Farts.

SW1TCK6EAR

DEPARTMENT

GENERALS ELECTRIC
PHILADELPHIA. PA.

I4AGNE-BLAST CIRCUIT BREAKER

QEI-88764

AM-13.8-500-5 (A)
A Letter Designation B, C, H, and V, used imraediately following
the model number indicates basic design features.
INTRODUCTION

The magne-blast circuit breaker is the removable interrupting
element for use in vertical-lift metal-clad switchgear, to provide
reliable control and protection of power systems. Among the many
advantages of metal-clad switchfeear are added protection to equip
ment and personnel, compactness, simplified installation and re
duced maintenance. In keeping with these features the magne-blast
breakers are designed for interchangeability and maneuverability,
together with reliability and low maintenance requirements.

N
O
«

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
legthens the arc and forces i t into intimate contact with cool diel
ectric material. A sturdy, reliable operating mechanism assures
low maintenance and long life.

CO
o

The AM-13.8 magne-blast breaker is available in a number of current
ratings.

Refer to the breaker nameplate for the complete rating
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 than
those given on the nameplate. Since this book is written to cover

& information of any particular breaker.
u

several ratings of breakers that are of the same general design, all
instructions will be of a general character and all illustrations
v;ill be typical, unless otherwise specified.
PROPER INSTALLATION AND MAINTENANCE ARE NECESSARy TO INSURE CON

TINUED SATISFACTORf OPERATION OP THE BREAKER.

The following instruc

tions will provide complete information for placing magne-blast
breakers in service and for maintaining satisfactory operation.

These instructions do not piu^ort to cover all details or variations
in equipment nor to provide for every possible oontingency to be met
in connection with installation, operation or maintenance. Should
further information be desired or should particular problems arise
v/hich are not covered sufficiently for the purchaser's pnaposes,
the matter should be referred to the General Electric Company.

GEI-88764
RECEIVING, HANDLING« AND STORAGE
Receiving and Handling

Each breaker Is carefully Inspected and packed by workmen experienced
In the proper handling and packing of electrical equipment. Immediate
ly upon receipt of the circuit breaker, an examination should be made

for any damage sustained In trauislt.

If Injury or rough handling Is

evident, a damage claim should be filed Immediately with the transportatlon company and the nearest General Electric Sales Office should be

•

notified.

It Is e3q)ected that due 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 exposure to moisture or dirt. Loose
parts associated with the breaker are eilways Included In the same crate.
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 permsinent location. If this Is not possible, the following pre
cautions must be tsiken to Insure the proper storage of the breaker;
1. The breaker should be carefully protected against condensation, pre
ferably by storing It In a warm dry room, since water absorption has

an adverse effect on the Insulation parts.

Circuit breakers for out- ^

door met£il-clad swltchgear should be stored In the equipment only
when power Is available and the heaters are In operation^ to prevent
condensation.

2. The breaker should be stored In a clean location, free from corrosive
gases or fumes; particular care should be taken to protect the equip
ment from moisture and cement dust, as this combination has a very
corrosive effect on many parts.

3. Machined parts of the operating mechanism, 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

1. Remove the box barrier and front cover and meike a visual Inspection
to ascertain that the breaker and mechsmlsm Is In satisfactory con
dition.
Check all bearing surfaces of the mechanism for lubrication.

Refer to section on Lubrication (page 15).
O

GEI-88764

2.
^

Charge the breaker closing springs manually using a 5/8" ratchet

wrench to turn the driving eccentric (6) Pig. 4. Turning the eccentrie counter 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.

Insert the spring blocking device (4) Pig. 4 and manually discharge
the springs against the pins by pushing the manual release button

(l) Pig. 4.

The springs are now blocked and slow closing of the

breaker contacts can 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 se
curely 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 beenoperated several times manually to
insure freedom of action.
adjustments:

a.
b.
c.

At this time, also check the following

Primary contact wipe (Refer to page 7]
Arcing contact wipe (Refer to page 7
Primary contact gap

(Refer to page 7]

"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. THIS PRECAUTION IS REQUIRED TO PREVENT
ACCIDENTAL CLOSING OR TRIPPING."

After the adjustments have been checked, the springs can be un
blocked. Rotate the driving eccentric until the indicator reads
"CHARGED" and the ratchet wheel no longer is advanced. The block
ing device can now be removed.

Attach test coupler to circuit breaker and operate electrically
several times. Check the control voltage as described under "CON
TROL POWER CHECK".

NOTE: If the breaker secondary wiring is to be given a hi-potential
test at 1500 volts, remove both the motor leads from the terminal
connection.

Failure to disconnect the motor from the circuit may

cause damage to the winding insulation.

4.
5.

Remove the test coupler and replace box barrier.
If breaker has been stored for a long period of time, it is recom
mended that the insulation be checked with a standard 60 cycle high

potential test.
6.

Refer to Insulation Test (Page 15).

Lubricate the silver portion of the primary disconnect studs by

rubbing a small amount of contact lubricant D50H47 to form a thin
coating on the ball contact.

GEI-88764
7.

Refer to metal-clad instruction book GEH-I802 for final instruc
tions before inserting the breaker into the metal-clad unit.

DESCRIPTION OF OPERATION

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 primary connections
to the associated metal-clad equipment are made through the primary
disconnect studs.

The ML-I3 operating mechanism shown in Figures 1, 2, and 3 is of the
stored energy type designed to give high speed closing and opening.
The mechanism will operate on a-c or d-c voltage and indicated on the
breaker nameplate. Closing and opening operations are controlled
electrically by the metal-clad or remote relaying, and mechanically by
the manual close and trip levers on the breaker.
All secondary con
nections from the breaker to the metal-clad unit are made through the

coupler (1) Fig. 1.
A positive interlock (2) Fig. 3 and interlock switch (2) Fig. 1 are
provided between the breaker and metal-clad unit to prevent raising
or lowering of 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 raised or lowered position. A plunger can also be provided to
operate an additional auxiliary switch mounted in the metal-clad unit.

A spring release interlock shown in Fig. 25 and 26 will, if the breaker
is in the closed position with closing springs charged, trip the
breaker open and hold the mechanism In a trip free position while
discharging the closing springs when Inserting or removing the breaker
from metal-clad unit.

When the breaker is Interchangeable with MS-13 solenoid operated
breakers in M-36 metal-clad units, motor circuit fuses are moqnted on

the breaker for protection.

These breakers are identified by the "G"

suffix in the breaker nomenclature.

In case when breakers with ML-13 operating mechanisms must match and

line up with breakers having ML-11 mechanisms the spring charging
circuit should be fused with Buss Company Fusetrons as follows:
Cont. Volt.

4a
4a
4a
2.5A
2.5A
2.5A

125v d-c
115V a-c
220V d-c

25OV d-c
23OV a-c

Cat. No.

Fm 10

Fm 4
Fm 4
Fm 4
Fm 2.5
Frn 2.5
Frn 2.5

GEI-88764

SPRING CHARGING

The mechanism consists of a high speed gear motor that compresses a
set of closing springs through the action of a simple eccentric, ratch

et, and pawl assembly.

The rotary action of the motor (2) Pig. 4 is

converted to a short straight stroke pumping action through the eccent

ric (6) and a lever that carries a spring loaded driving pawl (5).

The pawl advances the ratchet wheel (3) Fig. 3 only a few degrees each
stroke where it is held in position by the latching pawls (1). When
the ratchet wheel has been rotated approximately 180 degrees the clos

ing springs (6) will be fully compressed.

As the ratchet wheel con-

tinues to rotate, the spring load will shift over center and attempt

to discharge.

After only a few degrees of rotation, the closing roller

(10) Pig. 1 will engage the closing latch (11) and the compressed
springs will be held in repose until a closing operation is required.
Diiring the last few degrees of the ratchet wheel rotation the motor

and interlock switches (6) are released 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.

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 "CHARGED" and the driving
pawl no longer engages the ratchet wheel. The use of the ratchet wrench
provides for maximum safety in the event that control power is suddenly
restored without warning.
In this event, the motor drive will take
over again and continues to charge the springs.
Closing Operation

a cam (l6) Pig. 5 that closes the breaker through a simple linkage that
remains trip free at all times. A monitoring switch (11) Pig. 6 on the
^

closing latch will start the spring charging motor after it is fully
reset.

GEI-88764
Opening Operation

An electrical opening operation Is Initiated by energizing the trip
coll. This Is accomplished either by actuating the opening 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 coll, the trip plunger rotates the trip latch (7),
Pig.
causing the operating mechanism linkage to collapse. The
energy stored In the opening springs Is thus released, opening the
breaker. During this operation, the trip coll circuit Is deenerglzed,
and upon completion of the opening operation, the operating mechanism
Is returned to Its normal position, ready for closing.
As the breedcer opens, the main contacts part first, shunting the cur
rent through the arcing contacts. An arc forms as the arcing contacts

part.

See Fig. 7.

As the movable arcing contact (7) Is withdrawn

through the probes In the arc runner, the upper end of the arc Is trans

ferred to the upper arc runner (4). To assist the Interruption at this
point, a stream of air Is emitted from the booster tube (25) and forces
the arc onto the lower arc runner (8). Establishment of the arc on the
runners automatically Inserts the blowout colls Into the circuit. Intro
ducing a magnetic field between the pole pieces which tends to draw the
circ away from the arcing contacts. The Interrupter contains three up
per blowout colls and three lower blowout colls each Individually con
nected In series with Its respective section of arc runner. As the arc
Is forced outward along the diverging arc runners, the magnetic field
Is progressively Increased with the addition of each coll In the cir
cuit.

At the same time, the arc Is being forced Into the arc chute (3) which
Is composed of a series of gradually Interleaving Insulating fins.
These fins, which project alternately from the two opposite Inner sur
faces of the chute, elongate the arc Into a gradually deepening serpen
tine 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 pro
duced by the arc so cooled that the arc cannot reestablish Itself and.
Interruption occurs.
Manual tripping follows the same procedure except that Instead of ener

gizing the trip circuit, the manual trip (11) Pig. 2 Is used.
Trip Free Operation

If the trip coll circuit Is energized while the breaker Is closing, the

trip plunger will force the trip latch (8) Pig. 5 away from the trip
roller (9) causing the mechanism linkage to 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 operation.

GEI-88764
ADJUSTMENTS

All adjustments should be checked during periodic inspections and when
ever i t becomes necessary 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. First, however,
remove the breaker from the metal-clad unit and remove the box barriers
and front cover.

"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.
CLOSING OR TRIPPING."

THIS MEASURE IS REQUIRED TO PREVENT ACCIDENTAL

Primary Contact Wipe

When the breaker is closed, as shown in Fig. 8, the stationsiry primary
contacts (1) should rise 5/l6"4-0-I/16". Before checking this dimen

sion be sure the mechanism is re-set so that the prop pin (13) Fig. 5

is resting, on the prop.

To obtain the proper contact adjustment, open

the breaker and, referring to Fig. 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 increase it. Tighten the check nut,
close the breeiker and recheck the wipe. With the primary contact wipe

correctly adjusted, the clearance between the contact arm (6) and the
buffer block should be I/16" or greater (as shown in Fig. o) when the
breaker is fully closed.
Arcing Contact Wipe

Refer to Fig. 8.
touch.

Close the breaker until the arcing contacts Just

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 (l) and the movable primary
contact (2) should be 5/l6" or greater. This setting has been made in
the factory and no adjustment is provided. A wipe of less than 5/l6"
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 between the probes on the upper arc runner without touching.
Primary Contact Gap

Refer to Fig. 9. 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 contact (6) should be 5-1/4"+5/16"—1/8".

To change this gap, loosen the check nut (I7)j Fig- 5 and turn the

adjusting nut (I8) on stud (19).
'

decrease the primary contact gap.

Screwing the adjusting nut down will
Tighten the check nut and re-measure

the contact gap (close and trip the breaker before checking the mea
surement ).

GEI-88764
Trip Latch Wipe

Refer to Fig. 5.

The wipe of the trip latch (8) on the trip roller (9)

should be from 3/l6" to 1/4". This can be measured by putting a film
of grease on the latch (8), closing the breaker part way, and tripping.
The mechanism has the proper trip latch wipe when the latch rests

against the stop pin (23). No adjustment is provided and a visual in
spection is usually all that is required. If this setting is not cor

rect, look for insufficient travel of the trip shaft (7).
WHEN WORKING ON THE MECHANISM IN THE CLOSED POSITION, KEEP FINGERS

CLEAR OF THE LINKAGE, AS ACCIDENTAL TRIPPING CAN CAUSE SEVERE INJURY.
Trip Latch Clearance

Refer to Fig. 5.

With the breaker in the tripped position and the

closing springs charged, check the clearance between the trip latch (8)
eind the trip roller (9). It should measure 1/32" to l/l6".
Prop Clearance

Refer to Fig. 5.

With the breaker closed as far as possible, that is,

with the springs blocked and the cam (l6) rotated so that the prop pin
(13) is at its maximum height over the prop (l4), the clearance between
the prop and prop pin should be l/l6" to 5/32". No adjustment is pro
vided and a visual inspection is usually all that is required.
Release Latch Wipe

Refer to Fig. 6. The wipe between the release latch (3) and roller (2)
should be 3/16" to 1/4". If re-setting is required, loosen, set, and
re-tighten adjustment nut £ind screw (4).
Release Latch Monitoring Switch

bracket (20) Fig. 6 is 1/32" or less.
the switch striker.
any adjustments.

To obtain this adjustment bend

Be sure the latch is fully re-set before making

Motor and Relay Switches
With the closing springs blocked rotate the switch cam fl) Fig. 6 until

the switch striker (8) has traveled the maximum amount (about l80 de

grees rotation of cam). Loosen mounting bolt (l4) and rotate switch
support (15) until the gap between the striker (8) and support (15) is
1/32" or less.

GEI-88764
Interlock Switch Wipe

Refer to Pig. 10. Rotate the Interlock shaft (1) manually clockwise
to release the interlock switch stna (2). The point at which the con
tacts m^e can he determined with a circuit continuity tester such as
a light indicator or hell set.

switch

To obtain adjustment on the interlock

hend the interlock switch arm (2) until there is a maximum

of 1/32" clearance to the switch mounting plate (4).
Auxiliary Switch

' ™

The auxiliary switch (9)^ Pig. 11 is mounted on the left side of the

operating mechanism.

The shaft of the position indicator (8) operates

the auxiliary switch shaft which opens and closes the "a" and "h" con
tacts. The "a" contacts are open when the breaker is open eind the "h"
contacts are open when the breaker is closed. The "a" contacts should
close when the breaker primary contact gap is a minimum of 1". The "b"
contacts need only to be checked to see that they are open when the
breaker is closed. No adjustment is provided and a visual inspection
is usually all that is required.
Driving Pawl Adjustment

The driving pawl (5) Pig. 4 must advance the ratchet wheel (3) Pig. 3
sufficiently on each stroke to allow the latching pawls (1) to fall
into the ratchet teeth.

^
^

This should be checked with the maximum clos-

ing 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 (5) Fig. 4 has traveled
through its return stroke and check the maximum clearance between the
pawl and the ratchet tooth. Rotate the charging wrench until the driv
ing pawl has advanced the ratchet tooth to its msiximum travel. Now
check the clearance between the ratchet tooth £ind the latching pawl

(l) Pig. 3.

The clearance should be approximately equal for both the

driving and latching pawls and not less than .015

either case.

If adjustment is required for either pawl the springs must first be

fully charged and blocked.

Loosen seven motor support bolts (l) Pig.

15 £ind move entire motor assembly to the rear if the clearance is un
der the minimum at the latching pawls, and to the front if the clegu?ance is under the minimum at the driving pawl. Move the motor assembly

approximately twice the dimensional increase required at the pawl.

certain the motor assembly is moved streULght forward or rearward cuid
tighten the one bolt 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 cle2u?ance again checked as described
above.

GEI-88764
APXILIARY DEVICES

Latch Checking Switch

Refer to Fig. 12. Rotate the trip latch (4) clockwise (Looking at
the left side of the mechanism) "by pressing the manual trip lever
to open the latch checking switch operating arm (3). Allow the
trip latch to reset slowly and determine the point at which the
contacts make by using a circuit continuity tester^ such as a light
indicator or hell set. The contacts of the latch checking switch

should Just make when the gap between the trip latch (4) and the
stop pin (5) located on the crank (7) is I/I6". There should be a
minimum of 1/64" between the operating arm (3) Pig. 12 and the
switch (2) bend the latch checking switch operating arm (3).
Plunger Interlock

Refer to Pig. 13.

With the breaker in the open position, the

vertical distance "A" from the top of the interlock bolt (1) to

the bottom of the elevating bar (3) should be 10-7/32" plus or

minus 1/16".

To change this adjustment, add or remove washers (2).

Auxiliary Puses

Refer to Pig. 15. On breakers with "C" suffix, a set of protecting
fuses (4) are mounted on the front of the breaker. These fuses
will be the primary protection devices for the closing control
circuits on those breakers that are used in metal-clad units

designed for solenoid operated

breakers.

Inspection and Test

For ease in reviev;ing the adjustments, the following are
recapitulated;

a.
b.

c.
d.

Primary contact wipe; 5/16" + 0 - I/16".
Arcing contact wipe: 5/16" or greater (gap at primary
contacts).
Primary contact gap: 5-1/4"
5/I6" - 1/8".
Trip latch wipe: 3/16" to 1/4" v/ith trip latch resting

e.
f.

Trip latch clearance: 1/32" to I/I6".
Prop clearance: I/16" to 5/32".

against stop pin.

GEI-88764

g. Release latch v^lpe; 3/l6" to 1/4"
h. Release latch monitoring switch: Maximum clearance 1/32",
1. Motor and relay switch: maximum clearance 1/32".
J. Interlock switch: maximum clearance 1/32".
k. Auxiliary switch "a" contacts close when breaker pi»lmary contact
1.

n.
2.

gap Is 1" or greater.
Driving and Latching Pawl:
.015".

minimum clearance to ratchet teeth

Latch checking switch contacts make when the gap between the
trip latch and the stop pin Is 1/16".

Plunger Interlock:

10-7/32" plus or minus i/i6".

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, and test for possible grounds or short circuits.

See that all besirlng surfaces of the mechanism have been lubri
cated.

Refer to the section on LUBRICATION.

Operate the breaker slowly \flth the maniml charging wrench and note
that there Is no exesslve 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 Immediately.

Check the trip coll plunger and tl® release coll 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. This represents 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.
The opening speed of the arcing contact should be a minimum of 15 feet

per second.

This represents the average speed over 3 " fron the point

when the tip on the movable contact Is tangent to the lower surface of
the upper runner.
Control Power Check

After the mechanism has been closed and opened slowly several times with
the maintenance closing wrench and the mechanism adjustments are checked
as described, the operating voltages should be checked at the release as
described, the operating voltages should be checked at the release
coll, trip coll, and motor teimilnals. For electrical operation of the
mechanism, 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 nameplate.

The following ranges are standard:
11

250v d-c
115v a-c
230v a-c

Tripping
Range

Max.

50v
115V
130v
230V
26OV
125v
25OV

d-c
d-c
d-c
d-c
d-c
a-c
a-c

60v
125v
l40v
25OV
28OV
125v
25OV

d-c
d-c
d-c
d-c
d-c
a-c
a-c

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 of pow
er 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 simultaneously, 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 merely 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 (11) Pig. 2 or
the manual close button (7).
Before the breaker is finally raised into position in the metal-clad
unit, rub a small amount of G-E contact lubricant D50H47 on the silver

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

GENERAL 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 maintenance
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 lubrication of parts subject to wear is also vitally im
portant for the successful operation of the breaker.

GEI-88764
before any maintenance work is performed, make certain that all con-

trol circuits are opened and that the breaker is removed prom the
metal-clad unit, do not work on the breaker or mechanism while in
the closed position unless the prop and trip latch have been securely
wired or blocked to prevent accidental tripping, do not work on the
breaker or mechanism while the springs are charged unless they are
secured in that position by the maintenance spring blocking device.
Periodic Inspection

The frequency of periodic Inspection should be .determined by each

operating company on the basis of the number of operations (Including

operations which occur from time to time.

switching), the magnitude of currents Interrupted, and any unusual

Operating eixperlence will

soon establish a maintenance schedule which will give assurance of

proper breaker condition. On Installations where a combination of
fault duty and repetitive operation Is encountered, an Inspection Is
recommended after any severe fault operation. The following Instruc
tions list the main points to be Included In an Inspection and, a num
ber of general recommendations.
Arc Chutes

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 ex

pected 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 arc chute has suffered any mechsinlcal Injury due to dropping

or accidental striking, resulting In the actual breaking off of fins,
replacement of the chute will be necessary. Small broken corners on
the exhaust end of the chute will not Interfere with Its performance
and can also be disregarded.

4. The plastlsol flexible covering for the pole pieces (3 & 4) Fig. l6
^

and the upper mounting support (13) Fig. l6 should be Inspected for
breaks In the Insulation. If there are holes or breaks In the In
sulation they should be repaired or the part replaced.

Arc Chute Removal .

The arc chutes of the 13.8 KV breakers require a mechanical aid to re
move and replace them at general maintenance periods. This can be
accomplished by an overhead crane, a portable hoist, or by an arc
chute lifter especially designed for this purpose.

GEI-88764

The Arc Chute Lifter (l6) Pig. 19 bolts on the top plate of the breaker,
in line vrith the chute to be removed, and will lift, transport, and re
lease the chute as necessary.
To use the Arc Chute Lifter proceed as follows:

1. Remove box barrier (2) Fig. 7.
2. Remove one bolt (13) Fig. 19 from the top plate of the breaker on
the pole that the arc chute is to be removed.
3. Place the arc chute lifter over the rear bushing and replace bolt.

4. Lower grappling hooks (17) by turning handle (l4) clockwise until
hooks can be placed over lifting bolts (l8) in arc chute.

3. Turn handle counter clockwise until hooks begin to lift arc chute.

6. Loosen the two upper supporting bolts ( 2) Pig. 19 and the one lower

supporting bolt (9 ) Fig. 19 using a 3/4" wrench.
7. Turn handle of arc chute lifter counter clockwise and move chute

gently from side to side until both upper and lower supports are
clear.

8. Move trolly (15) Fig. 19 of the arc chute lifter to the rear.
9. Turn handle of arc chute lifter clockwise until arc chute is rest
ing on the floor and hooks can be removed.
Breaker Contacts

By removing the box barrier the movable and stationary primary contacts
and the movable arcing contacts can be inspected. The stationsucy arc
ing contacts can be inspected only after removing the arc chute assem
bly, as explained under REPAIR AND REPLACEMENT. If the contacts are

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

After completing inspection of the contacts, check the contact adjust
ments as specified under 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 inspected for any evidence of damage or excessive wear. Lubricate
the mechanism as outlined below, then, using the manual charging wrench,
open and close the breaker several times to make certain that the mecha
nism operates freely throughout its entire stroke. Check the mechanism
adjustments as specified under ADJUSTMENTS.
Check all terminal connec
tions.

Bushings and Insulation

The surface of the bushings should be kept clean and unmarred to pre
vent moisture absorption.
If the insulation surface should become
damaged, i t should be ssinded and deemed, euid should be refinished
with either cleeu:> varnish or clear resin.
Allow to dry smooth and hard.

GEI-88764

All other insulation parts on the breaker should be kept clean amd dry,
Smoke or dust collected between inspection periods should be wiped off,
and if dampness is apparent, heaters should be installed to insure dryness.

Insulation Test

When insulation has been repaired or replaced, or when breaker has been
stored under adverse conditions, i t is recommended that the insulation

be checked before the breaker is placed in service.

A standard 60 cycle

high potential test at 27,000 volts RMS will normally indicate whether
the breaker is satisfactory for service. With the breaker contacts in
the fully open position, apply the high potential to each terminal of
the breaker individually for one minute with all other terminals and
the breaker frame grounded. After high potentiaJ. 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 insiilation that may have been affected by moisture absorption.
If the breaker secondeiry wiring is to be given a hi-potential test at
1500 volts, remove both of the motor leads from the terminal boards.
Failure to disconnect the motor from the circuit may cause damage to
the winding insulation.
LUBRICATION

In order to maintain reliable operation, i t is important that all cir-

cuit breakers be properly lubricated at all times.

Most of the bear

ings and rolling surfaces utilize a new type of dry lubrication that
will require no maintenance and will last the life of the equipment.
Only few bearings and surfaces listed in the chart. Fig. 20, require

lubrication.

These have been properly lubricated, during assembly at

the factory, using the finest grades of
even the finest oils and greases have a
as evidenced by hardening and darkening
hardened lubricant is essential for the

breakers.

lubricants available. However,
tendency to oxidize with age,
in color. Elimination of the
proper operation of circuit

Also frequent operation of the breaker causes the lubricant

to be forced out from between the bearing surfaces. A simple lubrica
tion will often clear up minor disturbances which might be mistaken
for more serious trouble.

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 i t is overhauled, in ac
cordance with the lubrication chart. Fig. 20.
It is also recommended
that all circuit breakers be operated at regular intervals to insure
the user that the equipment is operating freely.

GEI-88764
The lubrication chart. Pig. 20, is divided into two methods of lubri
cation.

The f i r s t method outlines the maintenance lubrication which

General Electric Lubricants D50H15 and D50H47 are available in 1/4=**
collapsible tubes.

It is so packaged to insure cleanliness and to pre

vent oxidation.

Method of Cleaning Bearings

Whenever cleaning is required, as indicated in the lubrication chart,
the following procedures are recommended;
Sleeve Bearings

The sleeve bearings used throughout the linkage utilize Teflon surfaces
and do not require lubrication. 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 contaminates, such as dry or hardened grease.
If contaminants are present they should be removed by immersing the link
and bearing in clean petroleum solvent or similar cleaner and using a
stiff brush.
Do not remove the bearings from the links.
DO NOT USE CAR

BON TETRACHLORIDE.

The hinge of the primary contact arm (24) Pig. 7 should be disassembled,
cleaned, and lubricated with G-E D50H47 lubricant at general, overhaul
periods.

The main shaft bearings (24) Pig. 5 and the driving pawl lever bearing
should be removed, cleaned, and lubricated with G-E D50H15 lubricant
at general overhaul periods.
Roller & Needle Becirings

The cam follower bearings (6) Pig. 5, latch roller besiring (9)> and cam
shaft bearings (25) Pig. 5 should be first removed from the mechanism
and the inner race disassembled.

They should then be placed in a con

tainer of clean petroleum solvent or similar cleaner. DO 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
remove it. Ordinarily, by agitating the bearings in the cleaning solu
tion, and using a stiff brush to remove the solid particles, the bear
ings can be satisfactorily cleaned. Do not handle the bearings with
bare hands as deposits from the skin onto the bearings are inductive to
corrosion.
If the bearings are touched, the contamination can be re
moved by washing in alcohol.
After the bearings have been thoroughly
cleaned, spin them in clean new light machine oil vintil the cleaner or

^
™

GEI-88764

solvent is entirely removed.

Allow this oil to drain off euid then re-

pack them immediately with G-E lubricant D50H15 being sure all metal
p£irts are greased.

The removable seals should then be replaced.

NOTE: If it becomes necessary to clean the beairings 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 desir
able to leave the bearings in the alcohol for a longer time, an inhibit
ed gilcohol 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 Anti-Preeze and Du Font Zerone eu^e satisfactory for this purpose.

Precautions against the toxic effects of the alcohol must be exercised
by wearing rubber gloves sutid by using the alcohol in a well ventilated
room; excessive e3q)0sure to the fumes is sometimes unpleasant to person
nel. Washing the bearings in the light oil and draining should follow
immediately, then apply the lubricant.

Bearings that are pressed into the frame or other members such as the

eccentric drive bearings (7) Fig. 15 should not be removed.

After re

moving the shetft and inner race the bearing can usually be cleaned
satisfactorily 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 race and shaft.
Rolling Surfaces

A number of rolling and rubbing surfaces in the mechanism have been
lubricated with a baked-on, dry, molybdenum disulfide coating. This

requires no maintenance and should last the life of the breaker.
RECOMMENDED MAINTENANCE FOR MAGNE-BLAST BREAKERS APPLIED TO REPETITIVE

1. Magne-blast breakers applied to repetitive operation such as switch
ing arc furnaces and motors should be serviced and maintained ac
cording to the following schedule:

A. Every 2000 Operations, or Every Six Months - Whichever Comes First
1. Remove the box barriers.

2. Wipe all insulating parts clean of smoke deposit and dust with
a clean dry cloth, including the bushings, and the inside of
the box barriers.

3. All areas in the throat area of the arc chute should be thor
oughly cleaned by using sandpaper. This cleaning should be

performed any time the arc chute is removed.

The arc chute

fins should not be cleaned. Whenever the arc chute is removed,
loose dust and dirt should be blown out before replacing arc
chutes.

GEI-88764

4. Primary Contacts - Inspect the condition of the stationary con
tact 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).

the contact surfaces are only roughened or galled, they should
be smoothed with crocus cloth or draw filed.

After contact

dressing the primary contacts should be greased lightly with
D50H47.

5. Arcing Contacts - When the arcing contact wipe is less than the
minimum specified under ADJUSTMENTS, the contacts should be re

placed.

The contacts should be inspected for uneven wear and/

or damage using a mirror to inspect the stationary contacts.
Normally it will not be necessary to remove the arc chutes for
this 2000 operation servicing unless inadequate wipe or contact
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
or replacement. Do not grease the arcing contacts under any
circumstances.

6. Check the breaker and mechanism adjustments as summarized under
INSPECTION AND TEST. The necessary readjustments should be
made as described under ADJUSTMENTS.

7. The breaker and operating mechanism 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 contact support should be inspected for possible
need of replacement.

8. The contacts of the control relay should be inspected for wear
and cleaned if necessary.
9. Lubricate the breaker operating mechanism in accordance with
the table under LUBRICATION.

10. Inspect all wiring for tightness of connections and possible
damage to insulation.

11. After the breaker has been serviced, it should be slowly closed

and opened, as described in INSTALLATION, to be swe there is
no binding or friction and that the breeiker contacts can move
to the fully opened and fully closed positions. Its electrical
operation should then be checked using either the test cabinet
or the test couplers.

o
18

GEI-88764
^

B. After Every 10,000 Operations

1. In addition to the servicing done each 2,000 operations, the
arc chutes should be removed from the breaker and disassembled

to permit a detailed inspection of insulation, blow-out coils,
arc runners and assemblies which can become contaminated by arc
products.

2. The blow-out coils should be carefully exeimined and if the in
sulation has been cracked, shrunk or eroded from arc action and
heat so that the turns of the coils are not fully insulated
from each other, the coils should be replaced. All connections
should be checked for tightness.

3. The arc runners should be inspected and replaced when any part

of their area has been reduced to 25J^ of the original metal
thickness as a

result of arc erosion.

4. Check the stationary arc contacts to assure that the arcing con
tacts are in good condition and that their connections are tight.

5. Insulating material that is carbonized and cannot be satisfactor
ily cleaned should be replaced.

6. Any parts damaged or severely burned and/or eroded from arc ac
tion should be replaced.

NOTE: Pine cracks may develop in the fins of the arc chute
sides. This is to be e:q)ected with ceramic materials when sub

jected to the high heat of an arc and may be disregarded unless
they are long eind present a possibility of fin sections breaking
completely off. Small broken corners on the exhaust end of the
arc chute will not interfere with its performance and can also
be disregarded.

7. 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 replaced when reduced in
thickness to less than 1/32".

C. Every 20,000 Operations or Approximately Every Five Years - Which
ever Comes PirsTT

1. At this time the breaker should be given a general overhaul and
all excessively worn parts in both the mechanism eind breaker re

placed. Such wear will usually be indicated when the breaker
cannot be adjusted to instruction book tolerances. This overhaul
and inspection is more detailed and will require disassembly of
mechanism and breaker operating parts.
rs

GEI-88764
2. All roller and needle bearings in the operating mechanism
should be disassembled^ cleaned^ and repacked with O.E. lubri
cant D5OHI5 as described under LUBRICATION.

3. The stationary primary contact fingers should be disassembled
auid the silver-plated pivot area of the contact and contact

support cleaned and lubricated with 6-E lubricant P30H47.
4. The breaker and operating mechanism should be serviced as des
cribed for every 2,000 operations and properly adjusted before
being put back into service,

2, Magne-blast breakers applied to repetitive operation such as capaci
tor switching should be serviced and maintained according to the
preceeding recommendations, and in addition, should have items lAl,
1A2, and 1A3, repeated at 500 operation intervals.
TROUBLE SHOOTING

Failure of a breaker to operate properly will generally fall within four
.general classes; failure to trip, failure to close or latch closed,
closing springs will not recharge, and overheating. The following is a
brief outline showing psirticulsir types of distress that might be encoun
tered, together with suggestions for remedying 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 adjustments, latches, stops, auxiliary
devices, etc., in accordance with section on ADJUSTMENTS. Examine
latch and roller surfaces for corrosion.

3. Damaged trip coil.
REMEDY: Replace damaged coil.

4. Blown fuse in trip circuit.
REMEDY:

Replace blown fuse after detezmiining cause of failure.

5. Faulty connections in trip circuit.

1?^

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.

GEI-88764
2. Damaged or dirty contacts in control circuit.
REMEDY; Recondition or replace contacts.

3. Blown f.uise in closing circuit.
REMEDY: Replace blown fuse after determining cause of failure.

4. Faulty connection in charging circuit.
REMEDY:

Repair broken or loose wires and see that all binding screws

are tight.
Overheating

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

REMEDY:

Recondition or replace burned and pitted contacts, (Contacts

should be reconditioned very carefully and only when absolutely neces

sary. )
2. Contacts not properly aligned or adjusted.
FIEMEDY:
Check all adjustments in accordance with section on ADJUST
MENTS.

3. Breaker kept closed or open for too long a period.
REMEDY: Operate breaker more often to wipe contacts clean.
contacts if necessary.

Replace

4. Overloading.
REMEDY: Replace breaker with one of adequate rating for present or
future loadj or re-arrange circuits so as to remove excess load.
5. Primary connections of inadequate capacity.
REMEDY:

Increase size or number of conductors or remove excess cur

rent .

6. Loose connections or teiroinal 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
v^ious parts of the breaker in order to make any necessary repairs.
This section includes only those repairs that can be made at the instal
lation on parts of the breaker that are most subject to damage or wear.
IMPORTANT:
UPON COMPLETION OP ANY REPAIR WORK, ALL BREAKER AND MECHA
NISM ADJUSTMENTS MUST BE CHECKED.
Refer to the section on INSTALLATION,
paying particular attention to ADJUSTMENTS and FINAL INSPECTION.

OEI-88764

Arc Chute (To Inspect or replace blow-out colls)

To remove an arc chu'be^ first* open "the breaker and remove the box bar-

rler (2), Pig. 7.

Loosen the two upper supporting bolts (2) Pig. 19

and the one lower support bolt (9) using a 3/^" wrench, ^ raising the
complete arc chute assembly about 3/8"
sliding it toward the rear

of the breaker, it can be removed as shown in Pig. 19.
To disassemble the arc chute after it has been removed from the breaker,
proceed as follows:

1. Remove the assembly bolts (2,6,7*9^10,12, and 15)* Pig. 16.
2. Remove the side brace (l4), and rear brace (5), the upper pole
pieces (3), and the lower pole pieces (4), Pig. l6.
3. To remove the upper mounting support (13)* Pig. l6 remove the assem
bly bolts (l and 11), and the upper connection bolt.

4. Remove the assembly bolt (l8) to remove the lower brace (8) Pig. l6..
5. Remove the lower mounting support (l6) by removing the assembly

bolts (17) Pig. 16 and the connection nut (7)* Pig. l8.

6. At this point, the fiber side shields (4), Pig. i8, and the upper
arc runner assembly (2) 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 illustrated) as shown in Pig. 17.

8. The arc chute sides (6) Pig. 17, csui also be separated for inspec
tion.

Reassemble the arc chute in the reverse order.
should be noted during reassembly:

The following items

1. Equally space the fins of the arc chute sides before bolting together.

2. The gap between the fins at the rear of the arc chute should be 3/64"
to 3/32" measured at least 1" in from the back end of the arc chute
(see Pig. 21).
3. Check to insure that electrical connections to the blowout coils are
tight.

4. When reassembling the arc runner assemblies, check that the spacers
(1 and 10), Pig. 17* are correctly installed.

GEI-88764

5. 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.

6. Make certain that the electrical connections are tight.
To reassemble the £0*0 chute to the breaker, proceed as follows:

1. Rest the lower mounting support (8) on the arc chute mounting brack
et (7) as shown in Fig. 19.

2. Slide the arc chute forward and lift it slightly to engage the sup-

portly bolts (2), Fig. 19, in the slots of the upper mounting sup

port (3).
3. Check the spring baffle (11), Fig. 22, to assure that it closes the
gap between upper insulation (19), Pig. 16 and the back of the con
tact support (4), Fig. 22.

4. Tighten the supporting bolts (2 and 9) Pig. 19.

These bolts serve

as both the electrical and mechanical connections between the bush
ing and the arc runners.

5. Check that the movable arcing contact (4), Fig. 19, passes between

the probes on the upper arc runner (5) Fig. 17 without touching.

Contacts

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

A. Stationary Arcing Contacts (10), Fig. 22.
1. Disconnect the contact braids from the contact fingers by remov

ing two bolts (8), Fig. 22.
2. 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.

GEI-88764

B. Stationary Primary Contacts (9), Pig. 23

1. Compress tne contact spring (6),
2. Remove spring and spring guide (l).
3. Raise the contact finger to clear the prim£u?y 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. Apply a thin coating of D50H47 grease on the hinged edge of the

finger (9) then place it on the contact support (7) so that it
is retained hy stop plate (8).

2. Open spring compressor (3) and assemble spring guide, spring and
spring compressor (Pig. 23A).
3. Turn nut (2) in clockwise direction to compress contact spring
(Pig. 23B). Hold spring firmly in yoke on spring compressor to
prevent 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 cutout in primary finger (Pig. 230).
5. Hold spring assembly firmly in place and remove spring compressor.

C. Movable Arcing Contact (7)* Pig. 24

1. Remove the assembly bolts (8).
2. Reassemble in reverse order.

D. Movable Primary Contacts (5)^ Pig. 24 (1200 Amp. Breaker)
1. Remove the nuts from assembly bolts (6).
2. Remove the primary contacts.
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).

n
24

GEI-88764

4, Spread the contact arms (4) and remove the primary contacts (5).
5. Reassemble in the reverse order,

E. Contact Blade Assembly (4, 5, 7) Pig. 24
1. Remove the connection bar (9).

2. Remove the cup bearing (3) and the pin (11).

3. When reassembling, first insert the piston assembly (10), into
the booster cylinder and reassemble the cup beeiring (3).

4. Replace pin (11), and connection bar (9).
P. After disassembly and reassembly of any contacts, check all contact
adjustments as described under ADJUSTMENTS,
Bushings

IMPORTANT:

DO NOT REMOVE ALL SIX BUSHINGS AT ONCE.

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 fa
cilitate installation of the breaker in 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 dis
tance from that particular bushing to adjacent bushings in both directions, so that it may be reinstalled 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 metal-clad unit before
tightening the bushing mounting bolts. This must be done before the
£irc chutes are reinstalled.

To replace the bushing, proceed as follows:
Rear Bushing

1, Open the breaker and remove the box barrier eind arc chutes as al
ready described,

2, Remove the upper and lower horizontal barriers (l4 and I8), Fig, 7*
3, Remove the four bolts at the mounting flange of the re€tr bushing
being removed and lower the bushing assembly,

4, Referring to Pig, 23, disassemble the primary contact springs (6)
as previously described,

5, Disassemble the spring retainer (4) by removing mounting bolts (5).

GEI-88764

6» Referring to Fig. 22, disassemble the contact support (4) and arc
chute mounting bracket (2) by removing two bolts (3).

7. Reassemble in the reverse order.

The girc chute mounting bracket (2)

is not symmetrical and must be assembled correctly to orient the
chute properly on the breaker. The longest projection of the brack
et should be toward the lower end of the bushing.

Front Bushing

1. Open the breaker and remove the box barrier and arc chutes as slLready described.

2. Remove the upper and lower horizontal barriers (l8 and 20) Pig, 7.

3. Remove the connection bar (9), Pig. 24, cup bearing (3), and pin
^11 / •

4. Remove the four bolts at the mounting flange of the front bushing
being removed, and lower the bushing.

5. When reassembling, first mount the bushing and assemble the cup
bearing (3) contact arm (4), and replace pin (11). The contact sur
faces at the hinge point of the contact blade and bushing should
have a thin coating of D50H47 grease.

6. Check all contact adjustments as outlined under ADJUSTMENTS.
INTERLOCK SWITCH

To remove the interlock switch (3), 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 ADJUSTMENTS.
LATCH CHECKING SWITCH

To remove the latch checking switch (7), Fig. 10 (when furnished), re-

move the two mounting screws and disconnect the lead wires. Reassemble
in the reverse order and check the switch adjustments as explained un
der ADJUSTMENTS.

MOTOR. RELAY AND LIGHT SWITCHES

The three switches are mounted in tandem as shown in Fig. 6.
1. Remove the opening spring per instructions below.

2. Remove (2) mounting bolts (l4) from switch bracket (15).
3. Remove the (2) mo\inting screws of the lower switch.

4. Remove the (2) mounting screws of the center switch.
26

OEI-88764

3. Remove the (2) mounting screws of the upper switch.
6. Disconnect the lead wires of switch to be replaced.
7. Reassemble In the reverse order and check switch adjustment as
explained under ADJUSTMENTS.
TRIP SHAFT AND LA^fCH

1. Remove latch checking switch arm (10) Pig. 11 (when supplied).

2. Remove cotter pins on both ends of the shaft (12).
3. Remove set screw In latch (11).

4. Remove trip coll linkage bolt (6).

5. Place a block between the latch and frame (either side) and
drive shaft until the latch Is free of the key.

6. Remove key and all burrs that may be raised around the keyway on the
shaft.

Bui»rs will scar or shave the Teflon bearing surfaces If they

are not removed.

7. Reassemble the parts In the reverse order. Be sure the latch spring
Is properly Installed and the latch Is aligned In the center of the
latch roller.

Check latch adjustment as described under ADJUSTMENTS.

TRIP LATCH ROLLER BEARING

1. Remove (2) cotter pins at ends of shaft (8) Pig. 12.
2. Partially remove shaft out right side of frame until latch roller
(6) Is free.

3. Reassemble In reverse order with proper spacing of washers.

Be sure

latch roller rotates freely.
CLOSING LATCH

1. Remove cotter pins at both ends of latch shaft (19) Pig* 6.
2. Remove spring and paddle (l6) Pig. 6.
3. Remove set screws from latch (3) Pig* 6.

4. Move shaft (l4) to left (away from frame) by tapping lightly on the

Inside end of shaft. Rotate shaft and continue tapping until shaft
Is free. Shaft will push outside needle bearing from hotaslng.

qei-88764

5. Reassemble in reverse order putting bearing into frame last. Use a
small piece of tubing or pipe when inserting bearing to assure proper alignment.

6. Check latch adjustments as described under ADJUSTMENTS.
MOTOR SUPPORT

1. To remove motor support (8) Pig. 15* first remove the latch spring
{l6) Pig. 6.
2. Remove the retaining ring (9) Pig. 15 and link (10).
3. Remove motor leads from the terminal bo£u?d.

4. Remove six 3/8" bolts (l) Pig. 15 on bottom and one 3/8" bolt on
the right side (not shown).
5. Remove foiu:> mounting bolts from motor (not shown).

6. Remove the retaining ring (7) from the eccentric (2) Pig. 15.
7. Reassemble all parts of the motor support in the reverse order euid
re-align i t properly as described under DRIVING PAWL ADJUSTMENTS.
CAM

1. Remove 2 set screws from ratchet wheel (3) Pig. 3 and remove wheel
from main shaft (8).
2. Remove 2 set screws from cam (12) Pig. 1.
3. Remove prop reset spring (10) Pig. 2.

4. Remove 2 set screws from cam (l6). Pig. 5* 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.

5. Remove shaft out left side of frame,

6. Reassemble in reverse order using the correct number of washers and
spacers to properly locate the parts.

7. Rotate the mechanism through a closing operation using the manual

charging wrench. Check the location of the cam follower (6), Pig.
5* on the cam (l6). If necessary, move the cam to correct the
alignment.

Complete the closing operation and check the location

of the prop pin (13)* Pig. 5 on the prop (l4).
proximately centered.

It should be ap

GEI-88764
TRIP COIL

To replace the potential trip coil (2), Pig. 11 proceed as follows:
1. With the hreeiker in the open position, remove the two mounting bolts

(3).
2. Remove upper support (l) and spacers.
3. Cut wires at the butt connectors and remove coil,

4. When replacing the coil be sure to assemble the correct fiber spacers at the ends before bolting support (l).
5. Adjust coil location to allow approximately 1/4" of supmature travel
before latch starts to move.

6. Butt connect wires and check operation of solenoid electrically and
mechanically.
SPRING RELEASE COIL

To remove the spring release coil (5) Pig. 6 proceed as follows:
1. Block the closing springs as described in INSTALLATION.
2. Remove the left hand closing spring as described in CLOSING SPRINGS

below.

3. Remove two mounting bolts (17)* coil support (l8), and spacers.
4. Cut wires at the butt connectors and remove coil.

5. Replace the coil and the correct number of fiber spacers before
bolting support.

6. Butt connect wires and check that the armature is not binding.
Check coil for electrical operation.
CLOSING SPRINGS

The closing springs (6) Pig. 3 can be removed as follows:
1. Chsirge the springs with the manual charging wrench and apply the
spring blocking device as described in INSTALLATION.

2. Discharge springs by pushing manual close button (7) Pig. 2.

GEI-88764

Rotate cam shaft (8) Pig. 3 by using the manual charging

wrench until the gap between the spring (6) and the bearing
block (10) is 2 inches or more.

Lift both springs until they clear the lower supports, then
pull forward and down until the top supports are free.

Either discharge the opening springs by pushing the manual trip
lever or block the opening springs with a siiitable liocking
device.

OPENING SPRINGS

To remove the opening springs (9) Fig. 3 proceed as follows;
1.

Charge and block the clsing springs as described under
INSTALLATION.

Push manual trip lever (11) Pig. 2 to be sure the opening
springs are fully discharged.

Remove upper pin (12) Pig. 3 and lower pin (11).

After reassembling springs check the primary opening as
described under PRIMARY CONTACT GAP.

RENEWAL PARTS

It is recommended that sufficient renewal parts be carried in stock
to enable the prompt replacement of any worn, broken, or damaged
parts. A stock of such parts minimize service interruptions caused
by breakdowns, and saves time and expense. When continuous opera
tion is a primary consideration, 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 ori
ginal parts, since improvements are made from time to time. The
parts which are furnished, however, will be interchangeable.
The Renewal Parts List covers the following types of breakers;

AM-13.8-500-5C
AM-13.8-500-5CR
AM-13.8-500-5CB
AM-13.8-500-5CBR
AM-13.8-500-5H
AM-13.8-500-5HR
AM-13.8-500-5HB
AM-13.8-500-5HBR
30

AM-13.8-500-5HV-

1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A

& 2000A
2000A
& 2000A
& 2000A
& 2000A
& 2000A
& 2000A
& 2000A
2000A S;

AM-13.8-500-5HVB

1200A
1200A - 2000A
2000A &
& 2500A

The listed terms "Right" and "Left" apply when facing the mechanism end of the breaker.

ORDERING INSTRUCTIONS

1. Always specify the 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 lo
cally.

4. For prices, refer to the nearest office of the General Electric
Company.

Fig. 2 Front View ML-13
Operating Mechanism

Left Side View ML-13

Operating Mechanism

1. Secondary Coupler
2.

Interlock Switches

3. Auxiliary Switch

4. Latch Checking Switch
5.
6.
7.
8.
9.
10.
11.

Charge-Discharge Indicator
Power Switches
Closing Springs
Motor
Puses
Closing Latch Roller
Closing Latch

12.

Switch Cam

1.
2.
3.
4.
5.

Trip Coil
Open - Close Indicator
Auxiliary Switch
Counter
Trip Latch

6. Charge-Discharge Indicator
7.
8.
9.
10.
11.

Close Button
Motor
Fuse
Prop Spring
Trip Lever

Right Side View ML-13

1. Latching Pawls
2.

Positive Interlock Roller

Pig. 4

Spring Blocking Device

Close Button
Motor

3. Ratchet Wheel
4. Eccentric
5. Fuse

Spring Blocking Device
Driving Pawl

6. Closing Spring

Eccentric

7. Main Shaft Bearing
8. Cam Shaft
9. Opening Spring

Closing Spring
Manual Charging Wrench
Support Bolts
Charge-Discharge Indicator

10.

Guide Block

11. Lower Spring Pin
12. Upper Spring Pin

10. Trip Latch Roller Support

2.
3.
4.
5.

13. Prop Pin
14. Prop

Trip Coil Support
Trip Coil
Trip Armature

Prop Reset Spring

7. Trip Shaft
8. Trip Latch
9. Trip Latch Roller
VO
t-

00
CO
I

Opening Spring

Sectional Side View of Mechanism

6. Cam Follower Roller

•sl-

11. Crank Shaft
12. Cranks

15. Drive Shaft
10. Cam
17. Check Nut

Stop Plate
19. Spring Rod
20. Spring
21. Spring

l8.

22. Spring Guide

23.
24.
^5.

Stop Pin
Main Shaft Bearing
Cam Shaft Bearing

GEI-88764

Switch Cam

Closing Latch Roller
Closing Latch
Latch Adjusting Screw
Spring Release Solenoid

jf-

Control Relay
Latch Checking Switch

\^(

Switch Striker

Charge-Discharge
Indicator

Power Switches

Latch Monitoring Switch
Motor

14-U3I

Fuse

Switch Support Bolts
Switch Support
Closing Latch Spring
Release Coil Bolts

Release Coil Support

Closing Latch Shaft
Switch Mounting Bracket

Fig. 6

Control Mechanism

Primary Contact Wipe
Fig. 8

Arcing Contact Wipe
Contact Adjustments

1. Stationary Primary Contacts

4. Stationary Arcing

2. Movable Primary Contacts
3. Buffer Block

5. Movable Arcing Contacts

Cross Section of Breaker Pole Unit

Barrier Catch
Barrier
Chute
Runner, Upper

5. Blow Out Coil, Upper
6. Blow Out Core,

Upper

7. Movable Arcing Contact
8. Arc Runner, Lower

9. Blow Out Coil, Lower
10. Blow Out Core, Lower
11.

Pole Pieces

12. Front Bushing

13. Rear Bushing

14. Upper Horizontal Barrier
15. Main Operating Crank

16. Arc Chute Support
17. Spring Retainer
18. Lower Horizontal Barrier

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

Operating Rod
Stationary Arcing Contact
Stationary Primary Contact
Movable Primary Contact
Movable Contact Arm Assembly
Cup Bearing
Booster Tube and Piston
Front Vertical Barrier

27. Check Nut
28. Connection Bar

29. Booster Cylinder

GEI-88764

mi
Fig. 9 Adjustable Coupling for Making
Primary Contact Wipe Adjustments
1. Operating Rod
2. Operating Rod Pin
3. Adjusting Nut
4.

Check Nut

Pig. 10

5. Stationary Primary Contacts

6. Movable Primary Contacts
7. Contact Arm
8. Yoke

Positive Interlock Switch

1. Positive Interlock Shaft

6. Switch Support

2. Switch Arm

7- Latch Checking Switch

3. Interlock Switch
4. Switch Support

8. Switch Arm
9. Trip Shaft

5. Auxiliary Switch

GEI-88764

INI

1. Trip Coll Support
2.
3.
4.
5.

Trip Coil
Mounting Bolts
Counter
Trip Latch

kml

6. Trip Arm Screw
7. Manual Trip Lever

8. Open-Close Indicator
9. Auxiliary Switch
,10.

Auxiliary Switch and
Trip Coil

1. Switch Support
2. Latch Checking Switch
3. Switch Arm

4. Trip Latch
5. Reset Pin Stop
6. Latch Roller
7. Latch Roller Link
8.

Latch Roller Pin

Fig. 12

Latch Checking
Switch

3. Hex Charging Stud
4. Fuse
5. Manual Close Button

6. Motor
7. Retaining Ring

8. Motor Support
9. Retaining Ring
10. Driving Link

Assembly Bolts
Assembly Bolt'
Upper Pole Pieces
Lower Pole Pieces
Rear Brace

Assembly Bolt
Assembly Bolt
Lower Brace

Assembly Bolts
Assembly Bolts
Assembly Bolt
Assembly Bolts
Upper Mounting Support

Fig. 16

Arc Chute Assembly

Side Brace

Assembly Bolts
Lower Mounting Support
Assembly Bolts
Assembly Bolt
Upper Insulation

GEI-88764

1. Upper Arc Runner Spacers
2. Upper Arc Runner Assembly
3. Blowout Core
4. Blowout Coll

5.
6.
7.
8.
9.
10.

Upper Arc Runner
Arc Chute Side
Upper Insulation
Lower Arc Runner
Lower Arc Runner Assembly
Lower Arc Runner Spacers

1. Upper Mounting Support
2. Upper Arc Runner Assembly
3. Upper Arc Runner
4. Side Shield

5. Lower Arc Runner Assembly
6. Lower Coil Connection
7. Connection Nut

Fig. 19 Arc Chute Partially Removed Showing
Accessibility of Arcing Contacts
Rear Bushing
Supporting Bolt
Upper Arc Chute Support
Movable Arcing Contact
Mounting Bolts
Arc

Chute Brace

Support Bracket
Lower Arc Chute Support
Lower Supporting Bolt
Upper Horizontal Barriers

MM;

Lower Horizontal Barriers

Stationary Arcing Contacts

''' In-

Arc Chute Lifter Bolt
Handle

Trolly
Arc Chute Lifter

Grappling Hooks
Lifting Bolt
Arc Chute

Fig. 21

Arc Chute Pin Spacing

trip shaft, etc. (Teflon
coated bearings)
Sleeve Bearings - main crank
shaft, driving pawl lever.

(Bronze or cast iron)

LUBRICATION AT
MAINTENANCE
PERIOD

ALTERNATE LUBRICATION

No lubrication

No lubrication required.

(REQUIRES DISASSEMBLY)

required.

Light applica
tion of machine
oil SAE 20 or

SAE 30.

Contact Arm Hinge Assembly
Cup Bearing
Loose rings between bushing

No lubrication

Remove bearings or
links, clean per in
structions and apply
D5OHI5 lubricant liber
ally.

Roller and Needle Bearings

tion of machine
oil SAE 20 or

Clean per instructions
and repack with D5OHI5
lubricant.

SAE 30.

No lubrication

Ground surfaces such as

No lubrication required.

required.

cams, ratchet teeth, etc.

(Surfaces coated with M0S2)

Ground surfaces such as

latches, rollers, prop, etc.

Wipe clean and
apply D5OHI5

Wipe clean and apply
D5OHI5 lubricant.

lubricant.

Silver plated contacts and
primary disconnect studs.

Method of Installing Primary Contact Springs
Using a Spring Compressor

1. Spring Guide
2. Compressor Nut
3. Spring Compressor

4. Spring Retainer
5- Assembly Bolts

6. Spring
7. Contact Support

8. Stop Plate
9. Stationary Primary
Finger

OEI-88764

Fig. 22

Rear Bushing Assembly

1. Rear Bushing
2. Guide and Support for Arc

Fig. 24

Removal of Contacts

1. Contact Springs
2. Stationary Primary
Contacts

Chute

4. Contact Support

3. Cup Bearing
4. Contact Arm

5. Bolt for Flexible Braid

5. Movable Primary Contacts

6. Mounting Bolt

6. Assembly Bolts

7. Flexible Braid
8. Connection Bolt

8. Assembly Bolts

3. Bolts for Contact Support

9. Stud for Mounting Arcing
Fingers
10. Stationary Arcing Contact
Assembly
11. Spring Baffle
12. Insulating Plate

7. Movable Arcing Contact
9. Connection Bar
10. Piston Assembly
11. Hinge Pin
12.

Spring release
Interlock.

Pig. 26.

Spring release
Interlock

I3.8-5OO-I2OOA, 2000A & 25OOA

D
WITH

NIr-13 HECHANISH

aEI-88764
PARTS RECOriMENDED FOR NORMAL MAINTENANCE

In the tabulation below are listed the parts of those breakers which are
usually recommended for stock for normal maintenance.

263B292 P-2
281B708 G-1
2360791 G-1

3
3
3

2360791 G-4
2360790 G-9

3
3
3
3

Assembly
Insulating Plate
Insulating Plate

Buffer

6
6

Clamp for Buffer
Clamp for Buffer
Primary Contact Finger
Spring
Primary Contact Finger
Spring
Primary Contact Finger
Spring
Primary Contact Finger
Primary Contact Finger
lft)per Shield

All
All
All
All
All

All
All
All
1200
2000
1200

OIO8BI937POO5
6445087 P-4
6557243 P-1
6557243 P-2

1200
2000
All
7
All
7
All
7
All
2
12
All
All
27
1200
5
2000
5
1200
5
2000
5
All
All
All
12
All
12
All
12
All
12
All
All
12
6A
All
6f*
All
6A
All

All
All

2360791 P-8
2360791 P-8

All
All
All
All
All
All
All
All
All
All
All

All
All
All
All
All

414A194 P-2
0108B1937G001
0108B1937G002
414a116 p-2

456A336 P-1
802B742 G-3
137A9164 P-3
137A9164 P-3
137A9164 P-4
137A9164 P-4
2650163 P-2
802B735 P-1
421A201 P-1

10509393
10509393
10509393
10509393
10509393

P-1
P-2
P-3
p-2
P-3

137A7575 P-43
137A7575 P-42
137A7575 P-41

24
6
3
3
3
6
3
3
6
3
6
6
6
6
1
1
1
1
1

Booster Oylinder

Operating Rod Assembly

Flexible Connector (Left)

Flexible Connector (Right)
Stationary Arcing Contact

Tapper Shield (FfcLght)

Iftjper Shield (Left)
Insulating Plate
Lower Shield

Movable Arcing Contact
Movable Primary Contact
Movable Primary Contact
Movable Primary Contact
Movalale Primary Contact
I4)per Runner Insulation
Lower Runner Insulation
Lower Shield

Motor
Motor
Motor
Motor
Motor

48 VDC
110 VDC - 125 VDC
220 VDC - 250 VDC
115 VAC
230 VAC

lA Relay 48 VDC
lA Relay 110 VDC -

125 VDC

lA Relay 220 VDC - 250 VDC

137A7575 P-47
137A7575 P-45
6275070 G-1

lA Relay 115 VAC
lA Relay 230 VAC

6275070 G-2

2iF

Trip Coll - 24 VDC
Spring Release & Trip

All

6174582 G-1

Coll 48 VDC
Spring Release & Trip Coll

All

6174582 G-1

2# Spring Release & Trip Coll

All

6174582 G-15

2lf Spring Release & Trip Coll

All

6174582 G-2

2-f Spring Release & Trip Coll

All

6174582 G-IO

2iF- Spring Release & Trip Coll

All

6174582 G-14

2if Spring Release & Trip Coll

All
All
All
All
All
All

All
All
All
All
All
**A11

456A866 P-5
456A866 P-6
IOAXOO6 G-4

16ia4231
137A9252
161a4241

5
1
1
1
1

230 VAC
Switch Normally Open
Switch Normally Closed

Auxiliary Switch
Closing Latch Spring
Prop Spring
Pawl Spring

A Check connection dlagrom for (1) or (2) relay requirements,

(l) required for spring release and (1) required for tripping,
May be different voltages - check nameplate for requirements,

All except breakers with "B" In suffix,

Not shown,

For spring discharge l6lA5909.

A A All except breakers with letter "V" In suffix.
••

For new designs relay 137A7575 P-^3 Is P-4, P-42 Is P-1,
P-41 Is P-8, P-47 Is P-5 and P-45 Is P-2.

Operating Rod Assembly
Connection Base

Box Barrier Assembly

1
1
1
2
2
2
2

Box Barrier Support
Box Barrier Support
Box Barrier Support

3
3
3
3
6
6
6
3
3
3
3
3
3
3
3
3
3
3

Bearing
Spring

Front Wheel & Caster

Wheel & Spanner Bushing
Wheel
Front Wheel

Screw

Spacer
Spacer
Washer
Washer

Connection Arm Assembly
Washer
Washer
Washer

Bearing
Spring
Bearing Screw

Hinge
Hinge
Hinge
Hinge

Pin
Pin
Pin
Pin

Assembly
Assembly
Assembly
Assembly

Com.
Com.
Com.
Com.

*Thls assembly includes parts 24 and 36 inclusive.
AThose breakers model list numbers with "W" suffix.
**For both 2000 & 2500 Amps rating.

Pig. 29 {Ref.-70)
Rear Bushing Assembly

H
All
All
All

All

HB
All
All
All
All
H
All
H

006591738 P-001
026900853 P-022

P-114
P-114
P-004
P-005
P-013
P-008
p-009
P-002

0414A0180 p-001

023600790
023600790
082800782
082800782
082800782
082800782
025800666
025800666

* For ratings 2000 & 2500 Amps.

0121A5964
006509787 P-001

OIO8BI937 P-005
023600791 G-003
006445087 P-004
006557243 P-001
006557243 P-002
02360791 P-008
02360791 P-008
006176109 P-006

o4i4aoii6 P-004

All

023600790 G-005
02650151 P-025
026500151 P- 25

0175V0557 P-001

2360790 G-093
2360790 G-094
2360790 G-092
OIO8BI938 G-007
OIO8BI938 G-004
OIO8BI938 G-006
OIO8BI938 G-005
095800684 G-OOl
095800684 G-003
061900443 P-017
023600791 P-019
02360791 G-OOl
02360791 G-004

3
3
3
3
3
3
3
3
3
3
3
3
3
6
3
3
3
3
3
3
3
6
6

NO.
REQ

A A Types H & HB

Assembly
Assembly
Assembly
Assembly
Assembly
Assembly
Assembly

Fibre Washer

Spring
Spring
Spring Guide
Spring Guide
Spring Retainer
Spring Retainer
Contact Finger Retainer
Contact Finger Retainer
Contact Support
Contact Support
Jumper for Bushing

luring

Spacer for Spring Guide
Spring

Contact Finger
Contact Finger

Clamp for Buffer
Clamp for Buffer

Buffer

Insulating Plate
Insulating Plate
Arcing Contact Support

Baffle
Baffle

Locking Plate
Arching Contact Assembly

Flexible Connector
Flexible Connector

A/O Support
A/C Support

Rear Bushing
Rear Bushing
Rear Bushing
Rear Bushing
Rear Bushing
Hear Bushing
Rear Bushing
Bushing
Bushing

DESCRIPTION

•* All types except those with "B" suffix.
A Types HV & HVB

1200
1200
2000
1200
1200
2000

70
70
70
70
70
70
70
71
71
72
72
73L
73R

103
104
105
105A
106
107
108L
108R

O258CO615
026500161
OIO8BI943
OIO8BI943
OIO8BI943
096200750
011405304
011405304
011405304
011405304
011405304
011405304
011405304
011405304
011405304
011405304
011405304
011405304
0542E0747
0542EO747
0456ao864
025800615
025800616

P-015
P-006

3
6
3
3
6
6
6
6
6
3
3
3
3
3
3
3
3
3
3
3
3
3
3

109L

109R
llOL
llOR
lllL
lllR
112L
112R

113L
113R
115
116
117
120
121
122

123
124
125
126

127
128
129
130
131
132
133

P-006
P-009
P-012
P-010

P-013
P-017
P-014
P-002

P-005
P-003
P-006
P-004
P-007
G-003
G-004
P-104
P-029
P-018

0421A0208 P-434

025800615 P-Oll
006176109 P-089
0414A0102 P-008
006176109 P-091
0421A0209 P-082
0421A0208 P-093

006176109
096200750
096200750
006442389
0456AO888
068800589
0456AO310
006176109

36
18
18
3
3
3
3
6
6
12

Arc Chute Assembly, Com.
Arc Chute Side

Upper Support
Lower Support
Lower Brace
Rear Brace

Spacer
Side Brace
Shield
Lov/er Pole Piece
Lower Pole

Piece

Lower
Lower
Lower
Lov;er

Piece
Piece
Piece
Piece

Pole
Pole
Pole
Pole

Upper Pole Piece
Upper Pole Piece
Upper Pole Piece
Ift)per Pole Piece
Upper Pole Piece
Upper Pole Piece
Upper Runner Assembly
Lower Runner Assembly
Insulation Cap.
Core

Core Insulation

Spacer
J^acer
Spacer
Stud

Spacer
Spacer
Spacer
Spacer

A/O Support
A/O Support
Spacer
Spacer
Spacer
Bushing
Spacer

GEI-88764

ARC CHUTE (Con't)
REP.
NO.

0421A0208 p-497
O265COI5O P-015
096200750 P-003

096200750
026500163
026500163
0414A0194
0414a0196
026500150
04i4a0196
096200750
061900489
061900489
04i4a0198
025800616
025600150
0366A0743
026500155
026500155
026500155

p-002

P-008
P-002
P-002
P-001

P-013
P-002

P-007
P-006
P-005
P-001
P-011

026500154
026500154
026500154
026500154
0456AO888

P-001
P-002

G-003
G-005
G-OOl

G-009
P-003

0421A0208 P-022
0421A0208 P-018
006176109 P-006

0456AO336 P-001
O456AO89I P-210
068800512 G-002
026500161 P-017
0414A0131 P-004
0456AO891 P-208
0421A0201 P-001

O802BO735 P-001
061900494 P-009
O456AO89I P-103

As required.

Not sho^-m.

6
6
3
3
6
6
**6
6
6
6
3
3
3
3
3
3
3
6
3
6
3
3
3
3
6
3
3
9
12

24
24
6
3
3
3

Spacer
Spacer
Block
Dust Shield

Coil Support
Barrier

(Mycalex) Upper Shield
Spacer
Spacer
Spacer
Spacer

Lower Coil Support (Right)
Lower Coil Support (Left)
Insulation

Spacer
Connecting Strap

Coil fUpper)
Coil (Upper)
Coil (Lower)

Coil (Lower)
Insulation
Shim
Shim

Runner
Runner
Runner
Runner
Spacer
Spacer
Spacer
Spacer

Assembly
Assembly
Assembly
Assembly

(Mycalex) Lower Shield
Sleeve
Runner

Spacer
Spacer
6#

6
6

Shim - 1/16" Thick

Mycalex
Insulation
Shim

2#
# Shim 3/16" Thick

** For HV & HVB; l43L becomes 0108b1938 P-002 & l43R becomes
OIO8BI938 P-003.

GEI-88764
215 219 211
211

Fig. 31B For 1200 Amp,
All Ratings

Fig. 31A For 2000 Amp
Breakers, All Ratings

Fig. 32 Movable Contact Arm Assembly

(Ref. No. 210)

MOVABLE CONTACT ARM ASSEMBLY
REF.

214
214
215
215
216
217
218
218A

All
*

1200
*

1200

O236CO792
O236CO792
0802B0742
0137A9164
0137A9164
0137A9164
0137A9164
0258CO666
0258CO666
0236CO792
0236CO792
0258CO666

G-081
G-090

Movable Contact Arm Asm.

G-OOl

Arcing Contact
Primary Contact
Primary Contact
Primary Contact
Primary Contact

P-003
P-003
P-004
P-004
P-007
P-007
G-031
G-015
P-.OO6

Movable Contact Arm Asm.

Contact Arm
Contact Arm

Puffer Tube Assembly
Puffer Tube Assembly
Contact Arm

0421A0248 P-001

Piston Ring

0456AO874 p-003
0456AO874 P-002

Piston Ring Euallzer

0414a0146 P-054
0414a0146 P-053
*For 2000 & 2500 Amps Rating.

Piston Ring Expander (corr.)
(Smooth)
Nut

ML-13 STORED ENERGY MECHANISM

Fig. 33 Plunger Interlock for MIi-13 Mechanism
CAT. NO. FOR TYPE

Plunger Interlock, Comp,

325

023600787 P-012

1
1
1
1

Plunger
Bracket Assembly-

326
326
327

328
329
330
331
332
333

010509305 G-002
010509305 P-003

006509728 P-001
OI37A6O85 P-023
023600787 P-014

REQ.

1
1

010509305 P-014
010509305 P-006

Spring
Pin
Roller
Pin
Orank

Clip
Bolt

GEI-88764

^104
— 105
— 108

Fig. 34 Spring Release For ML-13 Mechanism
REF,
NO.

103
103
104
105
106
107
108
109*

011405352
011405341
011405343
011405343
011405343
011405343
011405324
011405343
011405342
011405342
011405341

G-002
P-002
P-012

G-003
G-004
P-007
P-006
p-008
G-003
p-008
p-008

011405352
011405352
011405343
011405343
011405343
011405343
011405324
011405343
011405342
011405342
011405341

G-002i
P-002
P-012

G-003
G-004
G-007
P-006
P-008
G-003
P-008
P-008

* Not shown in picture (position indicated).

DESCRIPTION

GEI-88764

PARTS REFERENCED IN PIG. S 35. 36 & 37
ARE FOR 1200, 2000 & 2500 AMPS RATING

0105C9300 P-006
0105C9301 P-004
0105C9301 P-004

2
1
2
1
1
1
1
1

CAT. NO.
FOR TYPE

5
7
13
14
16
18
19

0105C9301 G-002
0105C9302 G-OOl
0105C9312 G-OOl

20
21

0105C9310 G-004
0105C9304 P-003
O456AO885 P-021

0105C9302 G-002

0105C9302 P-004
0105C9301 p-007

74
93
126
127
128
129
130
131
132
133

016ia4287 G-OOl
OI37A9262
0137A9362
006076405 P-019

1 0

0456AO876 P-134
0456AO876 P-136
0114C5347 P-OO6

2
2
2
1
1

0114C5347
0145C9316
0258CO609
0114C5347
0105C9316
010509316
010509316
010509316
006076402
006076402
0161a4287
0456AO885
0456AO885
0456AO885
0456AO885
04i4A0112
0414A0112
04i4A0112
0414A0112

G-OOl
P-002
P-004
P-004
P-005
G-OOl
G-OOl
P-OO9
P-005
P-005
G-OOl
P-104
P-102
P-106
P-107
P-052
P-053
P-050
P-051

04i4A0112 P-001

1
1
*

DESCRIPTION

Crank
Crank
Link
Link
Link

Prop
Cam

Cam Shaft

Stop Pin
Bushing
Latch
Pin
Pin
Pin

Prop Spring
Shaft
Handle

Latch Spring
Reset Spring
Opening Spring Pin

(See 500)

A
1
1

1
1
1
1

Spacer
Spacer
Pole Piece

Coil Support (Tripping)

Coil Support (Tripping)
Crank
Armature
Link
Crank
Crank
Paddle
Pin

Bushing
Bushing
Bushing
Bushing

Bearing (O.R.)

Bearing (l.R.)
Bearing (o.R.)
Bearing (l.R.)

Fig. 35 Sectional Side
View of ML-I3 Mechanism
26

Fig. 37 ML-13 Mechanism (Sections)

•H

GEI-88764

REF.

170
171
175
223
5OOA
500
501
502
503

504
505

506
507

508

509
510
510
510
510
510
510
510
511

010509304 P-013
061900478 P-019
00607405 P-005
025800630 P-031
025800630 P-008
025800630 P-005
04i4a0109 p-008
025800630 P-007
010509304 P-006
0456AO808
0456AO807
010509304 P-002
06275070 G-002
06174582 G-OOl
06174582 G-OOl
06174582 G-015
06174582 G-002
06174582 G-OlO
06174582 G-014
V-6443518 P-001

3
A
A

A0
A0
A
A
A
A
A

DESCRIPTION

Key - Woodruff
Key - Sq.
Mech. Fr.
Pin

Con.

Open Spring Assembly

Pin (SEE 63)
Plate
Rod

Retaining Plate
Buffer
Clevis

Open Spring Yoke
Inner Spring
Outer Spring
Pin

48V DO Trip Coil

llOV DO Trip
125V DO Trip
220V DO Trip
25OV DO Trip
115V AO Trip
23OV AO Trip
Square Shaft

**
««

**
**

Coil
Coil
Coil
Coll
Coil
Coil

(2) for 13.8-1000-1200 Amps Breaker

(3) for 13.8-1000-3000 Amps Breaker
**

(1) Required for tripping possibly (l) for spring re
lease too may be different voltages.
plate for requirements.

Check name-

For 7.2-500-Both ratings breaker.
For All Others.

For 13.8-1000-3000 Amps Breaker.

Not a common part.

A A For breakers with spring release part 135 became

114053^1 P-005.

fflTiir' —

GEF-4429C
Supertedei GBF-4429B

RENEWAL PARTS
MAGNE-BLAST CIRCUIT BREAKERS
TYPES

AM-13.8-500-5C
AM.13.8.500.5H

AM-13.8-500-6C
AM-13.8-500-6H

NOTE: The ML-13 Mechanism is not included in this publication.
Refer to GEF-4379 for ML-13 Mechanism renewal parts.

ORDERING INSTRUCTIONS

t. Always specify the 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 nearest office of the General Electric Company.

Whan nrdtring ranawol psria, giva quonlily, catalog ngmbar, dascriplion of aoch Ham raquirad, and cotnplala namaplota raodlng.

GENERALB ELECTRIC

GEF.4429C

TYPE AM-T3.8 MAGNE-BLAST CfRCUIT BREAKERS

UiL.

(DWG 63403841

A. Breaker, Type AM-13.8-500

C. Hinge assembly (see Section A-A)
Fig. 1. Cross section views

(2000 Amps)

TYPE AM-U.8 MAGNE-BUVST CIRCUIT BREAKERS

GEF-4429C

Note: For recommended parts for normal maintenance,
refer to pages 16 and 17.

Type AM-13.8-500 Breaker (Refer to Fig. 1)
Ref.

733-0258C0680P009
0958C0682F009

7
8
—9
9
10
10
— 11
11
— 12
13
14
15
— 16
17

0265C0151P028
0836C0180P014
0258C0619G012

0802B0764G001
0263B02g2P002
0265C0151P030
0845D0123G003
0958C0683G003
0958C0628P005

0958C062eP006
0688C0Se6P020
0688C0586P0I3
0137A6047G005
02S5C0162CP017
0281B0708G001

0688C0589P017
0265C0176G001
0107B9348P007
0107B9348P005
0107B9348P002

095BC0682P009

0265C0151P028
0836C0180P014
0258C0619G012
0802B0764G001
0263B0292P002
026SC0151P030
084SD0123G003
0958C0683G003
0958C0628P0OS
095eC0626P006
0132C2738P003
0132C2738P005
0137A6047G005
0265C0162CP017
0281B070eG001
0688C0589P017
0265C0176G001
OI07B9348P007
0107B9348P005
0107B9348P002
0456A0862P008

AU
AU
All

AU
All
AU

t
t
H,C

0456A0862P008
0456A0862P001
006597296P007

0236C0768G007

0236C076BG007

2000
2000
1200
1200
2000

0898B0282G007

0898602820007

0898B0262G002
0898B02e2G006
0898B0282G001

0896B0282G002
0898802820006
0898B0282G001

19
20
21
22

•23
•23
•24
•24
25

HR, CR
H, C
HR, CR
AU
AU
AU
AU

2000
2000
2000
All
All
2000
All
1200
1200

1200

0456A0862P001
006597296P007

Description
Top plate
Angle
Box barrier clamp
Arc chute support

Arc chute clamp
Vertical barrier

Booster cylinder
Shim

Bushing, long
Bushing, long
Shim, 0. 005 in. thick

Shim, 0. 010 in. thick
Horizontal barrier, lower
Horizontal barrier, lower
Horizontal barrier, upper
Side barrier

Operating rod assembly
Connection bar

Box barrier assembly
Box barrier support
Box barrier support
Box barrier support
Front wheel and caster

Wheel and spanner bushing
Wheel
Front wheel and caster

Hinge
Hinge
Hinge
Hinge

pin
pin
pin
pin

006442257P001

0369A0407P001
006442258P001
006442246P001

0369A0407P001

Bearing
Spring

006442258P001
006442246P001

Spacer

0104A2495P001
0456A0884P001
006441630P001
006441617P001
0137A9168P001

0421A0239P001
0414A0106P004

0414A0106P004

* This assembly Includes parts 25 to 34 Inclusive.
••As required,

t Breaker model list numbers with "W" suffix.
i Breaker model list numbers without "W" suffix.

006441617P001
0137A9168P001

assembly,
assembly,
assembly,
assembly,

Screw

Bushing
Spring
Bearing screw

complete
complete
complete
complete

GEF-4429C

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

Rear bushing assembly (Ref. No. 70)

Front view

TYPE AM.13.8 MAGNE-BLAST CIRCUIT BREAKERS

GEF-4429C

Rear Bushing Assembly (Refer to Fig. 2)
Ref.
No.
70
70
70
70
70
70
-Jfl
71
<-72
72
73
74
75
76
77
78
78
78A
78B
78B
79
80
81
81
81
82
82
82
82
82
83
83
83
84
84
84
84
84
85
85
85
85
86
86
86
86
— 87
87
87
87
88
88
88
88
89
90

Amps
1200
1200
2000
1200
2000
2000
1200
2000
1200
2000
All
All
AU
All
All
All
All
AU
1200
2000
AU
AU
1200
1200
2000
1200
1200
1200
2000
2000
1200
1200
2000
1200
1200
1200
2000
2000
AU
1200
1200
2000
1200
1200
1200
2000
1200
1200
1200
2000
1200
1200
1200
2000
2000
All

Type
H,C
BA, BH
H,C, HB
HV
HVB

HV.HVB
All
AU
AU
AU
AU
All
AU
AU

H,C
HV, HVB
AU
AU
All
AU
AU

Catalos Number for Tvoe AM-13.8-500
-6C and -6H
-5C and -5H

733-0236C0790G093
0236C0790G094
0236C0790G092
010eB1938G007
0106B1938G004
0108B1938G006
0845D0124G003
0958C0684G003
06igC0443P017
0236C0791P019
0236C0791G001
0236C0791G004
0175V0S57P001
0236C0790G009
0265C0151P025
0414A0116F004
0108B1937P005

0236C0791G003
006445087P001
006557243P001
006557243P002
006557243P002
0114C5382P002
. . . .

. . . .

0414A0180P001
0121A5964P001

. . . .

0195A7388G002
0132C2722P005
0132C2722P004
0236C0791G003
006445087P004
0065S7243P001
006557243P002
006557243P002
0114CS382P002
0114C5382P002

0114C5382P002

. . . .

006176109P006
0414A0180P001

0121A5964P001

006509787P001

0121A5964P001

0236C0790P114
. . . .

. . . .

0828C0782P004
. . . .

0828C0782P005

N312P2542B
N312P2542B
N312P2542B
. . . .

0828C0782P004
0962C0778P007
0962C0778P007

0828C0782P013
. . . .

0828C0782P008
0258C0666P009

tt
B
AU
All
AU

0236C0791G001
0236C0791G004
0175V0557P001
0236C0760G009
0265C0151P025

0845D0124G003
0958C0684G005
0619C0443P017

0114C5382P002

tt
B
AU
AU

733-0213X0344G036
0213X0344G037
0213X0344G038

0258C0666P002
006591738P001
0269C0853P022

tt All TVpes except those with "B" suffix.

0828C0782P013
0962C0778P002
0962C0778P002
0258C0666P009
0g62C0778P011
0962C0778P011

0269C08S3P022

No.

Reqd.
3
3
3
3
3
3
3
3
3
3
3
3
6
3
3
3
3
3
3
3
3
3
6
6
6
12
12
18
24
18
12
18
18
12
12
18

Description
Rear bushing assembly

Rear bushing assembly
Rear bushing assembly
Rear bushing assembly
Rear bushing assembly
Rear bushing assembly
Bushing
Bushing

A/C ^pport
A/C Support
Flexible connector, right
Flexible connector, left
Locking plate
Arcing contact assembly
Baffle

Insulating plate

Insulating plate
Throat barrier assembly
Baffle
BafUe

Arcing contact support
Buffer

Clamp for buffer
Clamp for buffer
Clamp for buffer
Primary contact finger
Primary contact finger
Primary contact finger
Primary contact finger
Primary contact finger

Spacer for spring guide

^acer for spring guide

^acer for spring guide
Primary contact finger spring
Primary contact finger spring
Primary contact finger spring

Primary contact finger spring

18
24
12
18
18

Primary contact finger spring
Spring guide
Spring guide

3
3
3
3
Z
3
3
3
3
3
3
3
3
12

Spring retainer

^ring guide
^ing guide

^ring retainer
Spring retainer
^rii% retainer
Contact finger retainer
Contect finger retainer

Contact finger retainer
Contact
Contact
Contact
Contact
Contact

finger retainer
support
support
support
support
Jumper for bushing
Fibre washer

I'l

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

Complete arc chute assembly
("-6" early design)

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

GEF-4429C

Side cover removed

("-6" early design)

A. Complete arc chute assembly (Ref. No. 100)
ISS

IS2

139

137 158 I 159 I 135 i I3|
»

Complete arc chute assembly
("•6" later design)

Side cover removed

Component parts

{"-6" later design)
Fig. 3.

Fig. 3.

Arc chute (cont'd.)

Arc chute

Complete ore chute assembly
(different pole pieces and braces)

GEF-4429C

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

Arc Chute Assembly (Refer to Fig. 3)
Catalc a Number for Tvne AM-13.8

Ref.
No.

tlOO
101
102
103
104

dios
ii(106
107

((108
((109
((110
((111

-5

733-0213X0215G0H
0264B01COG007
0265B0150P002
0258C0615P015
0265C0161P006
0H4C5495G001
OH4C5495G002
0962C0750F006
0962C0701G004
0962C0701G005
0H4C5304G004
0H4C5304G005

lllA
lllB
lllC
HID
HIE
HIF
lllG
HIH

((112
((113
((114
((115
((116
H6A
H6B
H6C
H6D
H6E
H6F
H6G
H6H
H6J
H6K

((117
118

118
118
118
118
118

119
119
119
119
119
119
120
121

122
123
124
125
126
126
127
128
129

—

t -6 Later Design

Reqd.

733-0213X0215G015
0264B0100G017
0265C0150P002
0258C0615P015
0265C0161P006
0H4C5495G001
0H4C5495G002

733-0213X0215G019
0264B0100G017
0265C0150P002
0258C0615P015
0265C0161P006
0H4C5495G001
0H4C5495G002

3
3
3
3
6
3
3
6
3
3
3
3
3
3
3
3
3

. . .

. . .
. . .

. . .

0H4CS444G006
OH4C5444G007
—

—

0108B1943P004

. . .

0H4C5444G001
0H4C5444G002
0H4C5444G004
0H4C5444GOO5
—

—

0108B1943P005
. . .

0258C0615P029
0258C0615P008
0258C0615P006
—

—

0258C0616F018
—

—

0258C0616P018
0258C0616P010
0258C0616P020
—

—

006176109P417
0962C0750P009
0962C0750P010

. . .

0132C2736G001
0132C2736G002
0132C2736G003
0132C2736G004
0132C2736G005
0132C2736G006
0132C2738P001
. . .

0258C0615P029
—

0258C0615P019
0258C0615P03S

. . .

—

0421A0208P434
0258C0615POH
006176109P089
0414A0102P008
006176109P091
0421A0209P082
0421A0208P093

. . .

0132C2736G007
0132C2736G008
0132C2736G009
0132C2736G010
0132C2736GOH
0132C2736G012
0132C2738P002
. . .

—

. . .

—

0108B1943P001
0258C0615P029

. . .

—

0108B1943P002
0962C0701G002
0962C0701G003
OH4C5304G002
0H4C5304G003

No.

t -6 Early Design

0421A0208P434
0258C0615P0H

006176109P089
0414A0102P008
006176109P091
0421A0209P082
—

0421A0209P093
006176109P417
0962C0750P009
0962C0750P010

025SC0616P018

0258COG1GP023
0258C0616P026
0421A0208P434

0258C0615P0H
006176109P089
0414A0102P008
006176109P091
0421A0209P082
0421A0208P093

0962C0750P009

0962C0750P0],0

3
3
3
6
3
3
3
3
3
3
3

3
3
3
3
3
3
3
6
18
12
3
3
3

3
18
12
3
3
3
3
3
3
3
3
6
6
12
18
6
3
3

Description

Arc chute assembly, complete
Arc chiite sides

Upper support
Lower support
Lower brace
Rear brace
Side brace
Shield

Lower
Lower
Lower
Lower

pole
pole
pole
pole

pieces.
pieces.
pieces,
pieces,

left
left

right

Lower pole pieces.
Lower
Lower
Lower
Lower
Lower
Lower
Lower

pole pieces.
pole pieces.
pole pieces.
pole pieces,
pole pieces.
pole pieces,
pole pieces.

Upper pole pieces, left
Upper pole pieces, right
Upper pole pieces, left

Upper pole pieces, right
Upper
Upper
Upper
Upper
Upper
Upper
Upper
Upper
Upper
Upper

pole pieces,
pole pieces.
pole pieces.
pole pieces.
pole pieces,
pole pieces,
pole pieces.
pole pieces.
pole pieces,
pole pieces,

Core assembly, 2 13/16 in.
Core assembly, 2 13/16 in.
Core assembly, 2 15/16 in.
Core assembly, 3 3/8 in.
Core assembly, 2 11/16 in.
Core assembly, 3 3/16 in.
Core insulating tube for 2 13/16-in. core
Core insulating tube for 2 13/16-in. core
Core insulating tube for 2 15/16-in. core
Core insulating tube for 3 3/8-in. core
Core insulating tube for 2 11/16-in. core
Core insulating tube for 3 3/8-in. core
Spacer
Spacer

Spacer
Stud

Spacer
Spacer
Spacer
Spacer

a/c support
a/c support

t Before ordering parts for the -6 design, refer to the photos on page 7 to determine if you have the early or
later -6 design.

t For "HV, HVB" Breaker furnish Arc Chute Cat. No. 0108B1938G008, Upper Shield (right) Cat. No. 0108B1937G001 and
Upper Shield (left) Cat. No. 0108B1937G002.

right

^ Refer to Fig. 3Aand 3Dto determine proper arrangementfor side brace, rear brace and pole pieces.

t !

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

GEF-4429C

Arc Chute Assembly (Refer to Fig. 3) (Cont'd)
No.
130

131
132
133
134
134
135
136
137

No.

Catalog Number tor Type AM-13.8

Ref.

733-006442389P003
0456A0888P006
0688C0589P018
0137A9163F002

138
139
140

tl41

145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
•175

006176109iP070
0421A0208P497
0265C0150F015
0962C0750P003
0962C0750P002
0265C0163P008

0265C0163P002
0414A0194P002

006176109P070

0421A0208P497
0265C0150P015

0962C0750P003
0962C0750P002
0265C0163P008
0265C0163P009

0421A0208P497
0265C0150P015
0962C0750P003
0962C0750P002
0265C0163P008
0265C0163PC09

0195A7349G001
0196A7349G002

141

141
142
143
144

t -6 Early Design

0414A0196P001
0265C0150P013
0414A0196P002
0962C0750P007
0619C0489P006
0619C0489P005
0414A0198P001
0258C0616P011
0265C0150G006
0366A0743G001
0265C0155G003
0265C015SG008

0265C0155^006
0414A0116P002
0414A0197P001
0414A0197P002

0265C0154G003
0265C01S4G005
0265C0154G001
0265C0154G009
0456A0888P003
0421A0208P022
0421A0208P017
006176109P006
0456A0336P001
04S6A0891P210
0688C0512G002
0265C0161P017
0414A0131P004
0456A0891P208
0421A0201P0Oi
0802B0735P001
0619C0494P009
04S6A0891P103
0108Big43P003

177
177
178

0414A0196P001

0265C0150P013
0414A0196P002
0962C0750P007
0619C0489P006
0619C0489P005
0414A019BP001
0258C0616P011
0265C0150G006
0366A0743G001
026SC0155G003
0265C0155G008
026SC01S5G006
0108B5520P001

0414A0196P001
02C5C0150P013
0414A0196P002
0962C0750P007
0619C0489P006
0619C0489P005
0414A0198P001
0258C0616P011

0265C0150G006
0366A0743G001

02e5C0154G003
0132C2708P009
0132C2708P011
0265C01S4GO0g
0456A0888P003
0421A0208P022
0421A0208P017
006176109POG6
0456A0336P001
0456A0891P210

0265C015SG003
0265C0155G008
0265C0155G006
0108B5520P001
0414A0197F001
0414A0197P002
0265C0154G003
0132C2708P009
0132C2708P011
0265C0154G009
0456A0888P003
0421A0208P022
0421A0208P017
006176109P006
0132C2735P007
0456A0891P210

0132C2708G001

0265C0161P017
0414A0131P004
0456A0891P208
0421A0201P001
0802B0735P001
0619C0494P009

0414A0197P001
0414A0197P002

0114C5442G001
0114C5442G002

0114C5443G001

0132C2737G001
0132C2737G002
0114CS443G002

Description

Reqd.
Spacer

6
6
6
18
12
6
6
6
3

Spacer
Bushing
Spacer
Spacer
Spacer
Spacer
Block

3
6
6
6
3
3
6
6
6
3
3
3
3
3

Dust shield

Runner

3
6
3
6
3
3
3
3
6
3
3
9
12
24
36
6
3
3
3

Coil support
Barrier

Upper shield

Upper shield assembly, right
Upper shield assembly, left

S^cer

Spacer
Spacer

^cer
Lower coil support, right
Lower coil support, left
Insulation seal
Spacer

Coil, upper
Coil, upper

Coil, lower
Coil, lower
Insulating plate
Shim
Shim

Runner
Runner
Runner
Runner

assembly
assembly
assembly
assembly

Spacer

^acer
^>acer
^acer
Lower runner barrier
Sleeve
Runner

Lower runner shield
Lower runner insulation

Spacer
Throat cooler assembly, right

Throat cooler assembly, left
Shield and cooler assembly, right
^ield and cooler assembly, left
Muffler assembly

t Before ordering parts for the -6 design, refer to the photos on page 7 to determine if you have the early or

Breaker furnish Arc Chute Cat. No. 0108B1938G008, Upper Shield (ri^t) Cat. No. 0108B1937G001 and

Upper SMeld (left) Cat. No. 0108B1937G002.

* Not illustrated.

•* As required.

GEF-4429C

TYPE AM-13.8 MAGNE-BLAST CIRCUIT BREAKERS

Pre

UJi-

A. Breaker, Type AM-13.8-500

(2000 Amps)
C. Hinge assembly (see Section A-A)
Fig. 1. Cross section views

DESCHimiON
AMPS

NO.
REQ.

)
6E POUICR DCLIUIRV BND CONThDL
PHILRDILPHin, PtNNSVLUflNlft

AM BREAKER 13.8-500-5,-6,-7
BREAKER
TYPE

MOVABLE ARCING CONTACTS

0956C0684G003
0956C06a4Ga05

0845D0123G003
09S8C06S3G003

500-5,-6,-7
500-5.-6,-7

Oa02fl0742R003
0227A5306G004

STATIONARY ARCING CONTACTS

20C0A
2000A

ALL

500-5,-6.-7

FLEXIBLE CONNECTORS (RIGHT)
ALL
3
500-5,-6,-7

MOVABLE PRIMARY CONTACTS

1200V2000A
2000A
2000A

0137A9164P004
0137A9164P003"
0137A9164P004"
0114C5382P004'
0137A9164P003
OI37A9164P004
0114CS382P004

FLEXIBLE CONNECTORS (LEFT)
ALL
3
SOO-5,-6,-7

0114C5a82P002
0114C5382P002"
O114C5a02POO2*
0114G5382P002
0114C53a2P002

0414AOI80P0Or'
012lAS964POOr
0121A5964P001*
OO65O9707POO1
0121A5964P001

0236007906009

0236C0791G001

023600791G004

TUBE & PISTON ASSEMBLY

2000A

1200A

3
3
3

1200A
2000A
12CO/2000A

500-5
500-5
500-6

500-7
500-7

STATIONARY PRIMARY CONTACTS
I200A
1200A
1200A

2000A
2000A

PRIMARYCONTACT SPRINGS
12
500-5,-6,-7

1200A

500-6,-7

2000A
2000A

0236C0792R03I
023600792G015
0213X0343R094

0213X0343R092
0213X0343R094

OPERATING ROD ASSEMBLY

026500176G001
015205910RO01

BOOSTER CYLINDER

ALL

500-5,-6,-7 0263B0292P002

• UlBnEAKStSmra-VDEaQIMIION
'• AU MtAKERS EXC EPTtT DESONAnON

Page 30
C

)

6E PDIUEA OILIUCBV AND CONTBOl

rHILBOElPHIft, PENNIVLUBNIB

AM BREAKER 13.8-500-5,-6,-7
DESCRIPTION

50D-5.-6.-7
500-5.-6.-7

0845001236003
0958C0683G003

0958Ca684G003
0958C0684G005

MOVABLE ARCING CONTACTS
ALL
3
500-5

1200A
f200/2000A
2000A

0137A9164P003"
0137A9164P004"
01I4C5382P004'
0137A9164P003
0137A9164P004
0114CS382P004

PRIMARY CONTACT SPRINGS
120QA
12
500-5,-6,-7
500-6,-7

• AaBnEAKERswrm''8" oesqnahon
"ALLBREAKERS EXCEPT-B" OESQHAnON

Page 30

0114C5382P002
0t14C5382PO02"
0114C5382P002*
0114C5362P002
0114C5382P002

0414A0180P001"
0121A5964P001'
0121A5964P00r
008509787P001
0IZIA5964P001

0236C0790G009

500-5,-6,-7 023SC0791G001

FLEXIBLE CONNECTORS (LEFT)
ALL
3
500-5,-6,-7
TUBE & PISTON ASSEMBLY
1200A
3
500-5
2000A
120Q/2000A

STATIONARY PRIMARY CONTACTS

1200A

0802B0742R003
0227A5306G004

FLEXIBLE CONNECTORS (RIGHl)

MOVABLE PRIMARY CONTACTS

1200A

CATALOG NO.

STATIONARY ARCING CONTACTS

0236G0792R031
0238C0792G01S
0213X0343R094

0213X0343R092
02I3X0343R094

OPERATING ROD ASSEMBLY

ALL

500-5,-6,-7 028lB070eR001

0265C0t 76690,1
0152C591CR00t

BOOSTER CYLINDER

ALL

500-5,-6,-7 026aB0292P002

yiAG^-JE-BLAST OXRCUIT BRSAKE':?

AM-13.8-730-2 (A) and AM-13,8-750-3 (^)
A Letter Designation B, C, and H, used Inuiiediately ro.llovrlng the "
niodel number indicates basic design features.

, INTRODUCTION

The magne-blast circuit breedcer is the removable interrupting el«aent
for use in vertical-lift metal-clad switchgear, to provide reliable
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 in-terchangeabllity and maneuverability, together with reliability and low
maintenance requirements.

The magne-blast circuit breaker operates on the principle that an arc
nan be interrupted in air by sufficiently elongating and cooling" it.

This is accon^lished by means of a strong magnetic field that lengthens
the arc and forces it into intimate contact with cool dielectric, ma- •
terial.
•••and-long

A sturdy, reliable operating mechanism assures-low maihtenarice
life.

•The AM-13.8 magne-blast breaker is available in a number of current

ratings.

Refer to the breaker nameplate for the complete rating Infor

mation 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 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 MAINTENANCE,ARE NECESSARY TO INSURE CONTINUED
SATISPAOTOHY OPERATION OP THE BREAKER. The following instructions will
pTOvide complete information for placing magne-blast breakers in ser^
vice and for maintaining satisfactory operation.

These Instructions do* not purport to cover all details or variations f
In equipment nor to provide for every possibis contingency to be .met.:

in connection with installation, operation or maintenance.

Should

further infoiroation. be desired or should particular pi^obiems arls.©' .
which are not covered sufficiently for the purchaser's oiirooses, the
matter should be referred to the General Electric Company.*
1

H: •-:; .: hAvIup:

-ija: • STORAGE

r:'^^-^^jl.Lng

Each breaker ib carefully Inspected and packed by workmen experienced

in the proper handling .and packing of^''_eiectrlcal 'equipment,'':;.Dnaiediate-r-'^'

:.y lipon receipt of the circuit breaker, an examination should be made

"c ' :.ny carrvSge sustained in transit . v If injury or roi^gh, handling is
e--iaent, a damage claim should be filed immediately with the tJi'dnsppr--:
:;...rion company and the nearest General Electric Sales Office should be | i

!Ct is expicted that due care vfill be exercised during the; unpacking

,r:! iuctailation of the orsaker so that no damage will occur from careij ,c or- r-ourh nan-iiing^ or from exposure to moisture or dirt.

Loose- '

1. v.i accociatoc; with the breaker are always included in the same crate.
' • r-x
parts against the packing list to be 'sure that no parts have
leic cverlooked.

•

;i-; ;• c •

-:-i::-P - •

It is recomraended that the breaker be put into service immediately in

Its permanent location. ; If, this; Is hot Iposslble,
fbaidwingl&e-^
.cautions muso be taken to insure' the /proper storai^; of; the?^
,
,
.

snoui.d be carefully prh^ect'ed against condensation, :prelerably by storing .it in a waimi dry 'i*6om, since water absorption has

:jje^er"'''\

Deiore lu is plaoeu in. service.Li;"• Py ''i-f
'S'l'A.ZZAHXi

front cover and make a .vl

breaker and raechanlsm is-in satisfactory coh-

surfaces
of the mechanism
onbearing
Lubrication
(Page'15),
• .•
; for lubricetior

:>niten the spring^ have reached the^JTully chained PiQSitioh'fc^
• -cator'(10) ]7igV'4 will read ^-'CHARGSaj"/iarid'ijheiXiidvJ^

.raised

the rochet 'wheei;r:teeijh;::; ;J^ditlbnal -lju^

: .xenpric will not/advance'the'(ralJdhefc:l-wheel»^;;'J^X;l,./:;-,,v/',i,
• :

• ' :ihsert the spring blockings device (4) Figi' ^ ^d imanually disph^

the spi'ijigs against "the pine-^y^ pushii^ the vm^ual':^^

•,.

(l) Fig/ !^. (Ths' ^rings are now blpcked and; sloi^ closlr^^
,' breaker 'cphtacts-''cdh ;be'- acc6n^Iiehe^:\by(:'againi(i^^

;
;

.eccentric

•

;inrring .the slow closing'operation "check to ihsiu^e that the .mechanibBi
does not stick or bind din?ing the'entire strbkeV; that It la^^^
: e-urely in the closed- position> and/that" i t trips 'freely when the'rs^waii-- '
• •uai trip leyer is operated. 'The breaker should: not,...be >op

.eiectrically until it has been {pp^ated; Several.;(bln^e
oinsure '-freedom/of//actionv;/;;''Attitii^i^tin^
'

•ri/i;

•

" '

.;//,x;'hi////Prltniary contact "gap', , •' ...(Refer:/to. -pege,/7^//;?:v^^^^^
-

;/- /;

'SC. "Prijnai^^ /cbntact^^
b. Arcing contact'wipe: ''' W

. ;

• ' . "SO NOT ¥ORK Oh EITHER THE-^AKER OR MECHANI^'^^^

:. SPF.I.WGS ARE BLbCKED vAm: THE' OPENING'SPRIWOS HAVE :BM/T^

• . . ^OH• ^^CHAittCAII^;: BiOOKEbi• :• THiSbpRECAUTiO^

;/v.;g/:ApGiDENTA|/

" ^

'•'I'li'•

'"'•ii;;';,,After. the >ad.Ju3tniehta' have 'been-checked,.'the, spitnge'cah/l^^'i^v;^

" A; 1 •/ ':
'' .•

blocked. . Rotate/the driving;etcer^rlc untllAtheAiacatator-^
' . "A
>ACHARGSD'^/andithe ratchet wheejt no';lbngerAis :a^a^
The-bic^king^

/•.device can now be removed,

Attach test co"upler'to'circuit breaker, and-operateAelectrld^^
several times. Check the control voltage as/described under "c6N'«
TRGLAPOWERACHSCK'^-^

.'-N

• ^/.;

• •. /.

NO^;;''^ If thevbreaker.^^.;-;^^

--A'

wixdng is to be given a hi-potehtial

.'A/. .beSt''at//il^QQ;:vbitjeyArohk)veAbdthAtMAniotpi^''iea;^^

:^<;

:' // cdnnectibn. '/Failure tp'';discQhne causing the operating mechanism linkage to collapse. The

GEI-88765
•k

energy stored in the opening springs is thus released, opening the

"breaker. During this operation, the trip coil circuit ic deenerglzed,
^g^^^^and upon completion of the opening operation, the operacJ.ng mechanism'

>is returned to its normal position, ready for closing.

rent^throuS^^th^^f'^®-?
plrt Se^i? 7

"lain contacts part first, shunting the curSn* ^
contacts

irom tne area of
upper contact
end of the
la i-pana
from*the
Af the farc runner,
movablethearcing
(27)arc
is withdrawn

point
the

interruption at'this

emitted from the booster tube (28) and forces

dSS®
duclns aautomatloalirinsertrthe
magnetic field between thebiowiut®ooll"in?rtoe^oirouir
pole pieces which tJnds t^droiIntro®
^hr
Sowou?^cSs and
lnterrupSrconla?L'?oS%per
in ^eli?oo
??
lower blowout colls each individually connected

• forced
fnv. a outward
<.
j along
its respective
section
arc runner.
As the fioirt
arc i
the diverging
arc ofrunners,
the'raaenetlc

i^progresslvely Increased wltS Se addltlofSf lach^l?!"S SS clr-

'Is romrnJSa
Theqe

• wSroath

Swi 1,

"'f afo Is being forced Into the arc chute (8) which
gradually Interleaving Insulating nns

i ? project alternately from the two opposite Inner sur-

rapidl? lAoreaSd and the

interruption loou?s.®°

^ Sraduallfdeepeni^S LS^h-

resistance in the path of the arc Is
reestablish Itself and,

follows the same procedure except that Instead of ener-

glzlng the trip circuit, the manual trip (ii) pig. 2 Is used?
Trip Free Operation

coil circuit Is energized while the breaker -! s clos-^ns the

trip plunger will force the trip latch (8) Pis: s awav fi-om

roller (9) causing the mechanism linkage to collapse and the breicer ^o
re-open, ^e closing cam 16) will complete itfclL?^ S^okf^d t^e
springs will re-charge as In a normal closing operSio?^
. ADJUSTMENTS

All adjustments should be checked during periodic insnpft--! iSnes anri irv>o«

S:rraS®frorcover?" ' ® -^-'-"d'SnJt anrro^ve^'iSI'boS'w!''
'.9

GEl-88765
NOT WGITEC ON EITHER THE BREAKER OR IWECHANISl^I MLSSS THE CLOSINGSPRINGS ARE BLOCKED AND THE OPENING SPRINGS HAVE BEEN TRIPPED-OPSN OR
jr.i
jj

MECHAI«;CALLY BLOCKED.

THIS MEASURE IS REQUIRED TO PREVENT ACCIDENTAL

CLOSING OR TRIPPINGo"
Pritnary Contact Wipe

When the breaker-Is closed, as shovm in Pie. 8. the stationary primary

contacts (l) shodild rise to a dimension of 5/l6"+0-l/l6. Before check
ing this dimension be sure the mechanism is re-set so that the prop pin

(13) Pig. 5 is resting on the prop. To obtain the proper contact ad
justment, open the breaker and, referring to Fig. 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 increase It.
Tighten the check nut, close the breaker and recheck the wipe. With
the primary contact wipe correctly adjusted, the clearance between the '

contact arm (6) and the buffer block should be I/I6" or greater (as
shown in Pig. 8) when the breaker is fully closed.
Arcing Contact Wipe

Refer to Fig, 8.

touch.

Close the breaker until the arcing contacts Just

This can be determined with the use of a circuit•^ntlnuity

tester such as a light indicator or bell set.

In this position, the •

gap between the stationary primary contacts (l) and the movable prlmEuv
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 usually an indication that the arcing contacts need to be replaced.,
V/hen making this check, also see that the movable arcing contact
does not touch the upper runneri
Primary Contact Gap

(5) and the movable primary contact (6) should be 5-1/4"-#-5/I6"—1/8".:

To change this gap, loosen the check nut (17)» Pig. 5 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-measm^

the contact gap (close and trip the breaker before checking the mea
surement).

Trip Latch Wipe

Refer to Pig. 5. The wipe of the trip latch (8) on the trip roller (9)
should be from 3/16" to 1/4". This can be measured by putting a film i
of grease on the latch (8), closing the breaker part way, and tripping;,;
The mechanism has the proper trip latch wipe when the latch rests
against the stop pin (23). No adjustment is provided and a visual

i
•

GrEi.—boT
V

inspection is usually all that is required.

If this setting is not correctj loOiC for insufficient travel of the trip shaft (7)»

\WHEN WORKING ON THE MECHANISM IN THE CLOSED POSITION, KEEP FINGERS

CLEAR OP THE LINKAGE, AS ACCIDENTAL TRIPPING CAN CAUSE SEVERE INJURY.

Trip Latch Clearance

Refer to Fig. 5« With the breaker in the tripped position and the
closing springs charged., check the clearance between the trip latch :

(8) and the trip roller (9).

It should measure 1/32" to l/l6«.

Prop Clearance

Refer to Fig. 5. With the breaker closed as far as possible, that is,
with the springs blocked and the cam (l6) rotated so that the prop pin
(13) is at its raaxinium height over the prop (l4), the clearance between
the prop and prop pin should be l/l6" to 5/32". No adjustment is pro
vided and a visual inspection is usually all that is required.
Release Latch Wipe

The wipe between the release latch (3) and roller (2)

sho^d be 3/l6 to l/4". If re-setting is required, loosen, set, and^^ .: • •

re-tighten adjustment nut and screw (4y.

7 ;^

Release Latch Monitoring Switch

The release latch must be fully re-set and the monitoring switch opex^4

tea before the motor will start. The switch should be wiped by the
striker so that the clearance between the striker and switch mounting

brackeo (20) Fig. o is 1/32" or less. To obtain this adjustment bend
the switch striker.

Be sure the latch is fully re-set before making

any adjustments.

Motor and Relay Switches

\\ioh the closi^ sprigs blocked rotate the switch cam (1) Pig. 6 untlL
une switch^striker (8) has traveled the maximum-amount (about 18Q de
grees ^tation of cam). Loosen mounting bolt (l4) an4 rotate switch

(^5) until the gap between the striker (8) and support (15) is

1/32" or less.

Interlock.Switch Wioe

Refer to Fig. 10. Rotate the interlock shaft (l) manually clockwise
tc release the interlock sv.itch arm (2). The point at which the con-'
uaccs i^e can be determined with a circuit continuity tester such as
-1,71 u

obtain adjustment on the interlock
interlock switch arm (2) until there is a maximum

01 l/b2 clearance to the switch mounting plate (4).

;

# {'V '
^

•

GEI-88765
' Au:?:lllary Sv/itch

The aiucillary sv/itch (9), Fig. 11 is mounted on the left side of the
operating mechanism. The shaft of the position indicator (8) operates
the auxiliary switch shai't v/hich opens and closes the "a" and "b" con

tacts.

The "a" contacts are open when the breaker is open and the "b"

contacts are open when the breaker is closed.

The "a" contacts should

close when the breaker primary contact gap is a minimum of 1".

The "b"

contacts need only to be checked to see that they are open when the
breaker is closed. No adjustment is provided and a visual inspection

is usually all that is required.

Driving Pawl Adjustment

The driving pawl (5) Pig. 4 must advance the ratchet wheel (3) Pig. 3.
sufficiently on each stroke to allow the latching pawls (l) to fall
into the ratchet teeth.

This should be checked with the maximum clos

ing spring load against the driving members.

With the mechanism un- .

blocked, 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 (5) Pig. 4 has traveled
:
through its return stroke and check the maximum clearance between the

pawl and the ratchet tooth.

Rotate the charging wrench until the di*ly-:

ing pawl has advanced the ratchet topth to its maximum travel. Now
check the clearance between the ratchet tooth and the latching pawl

(1) Pig. 3.

The clearance should be approximately equal for both the

driving and latching pawls and not less than .015" in either case.

•

;•

If adjustment is required for either pawl the springs must first be

fully charged and blocked.

Loosen seven motor support bolts (ly Pig. ;

I5 and move entire motor assembly to the rear if the clearance is un

der the minimum at the latching pawls, and to the front if the clear- •

ance £s under the minimum at the driving pawl.

Move the motor assembly

approximately twice the dimensional increase required at the pawl. Be '
certain the motor assembly is moved straight forward or rearward and
tighten the one bolt 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 !
above.

, /v •"

AUXILIARY DEVICES

Latch Checking Switch

Refer to Pig. 12. Rotate the trip latch (4) clockwise (looking at the
left side of the mechanism) by pressing the manual trip lever to open-

the latch checking sv-itch operating arm (3). Allow the trip latch to
reset slowly and determine the point at which the contacts make by using'
a circuit continuity tester, such as a light indicator or bell set.
•
The contacts of the latch checking switch should just make when the

gap between the trip latch (4) and the stop pin (5) located on the •
crank (7) is I/16". There should be a minimum of l/64" between the
operating arm (3) Pig. 12 and the switch support (l). To obtain ad
justment of the latch checking switch (2) bend the latch checking
switch operating arm (3),

^^ith the breaker in the close position, the vertical

distance k" from the top of the interlock bolt (l) to the bottom of
the elevating bar (3) should be 11-9/32" plus or minus I/I6". To
change this adjustment, add or remove washers (2).
Spring Release Interlock

A spring release.interlock shown in Fig. (oA) will assure that the

breaker contacts are open and the closing springs discharged when

inserting or removing the breaker from the metal-clad unit. If the
closing springs are charged and/or the 'breaker is in the closed

position when being inserted or withdrawn from the metal-clad unit,
the release interlock v/ill trip the breaker open and hold the mechan
ism in a trip-free position while discharging the closing springs*
Auxiliary Fuses

Refer to Pig. 15.

On breakers with "C" suffixes, a set of protectingf#

fuses (4) are mounted on the front of the breaker.

These fuses will ^

be the primary protection devices for the closing control circuits
on those breakers that are used in metal-clad units designed for sole

-. 'f-

noid operated breakers.
Inspection and Test

For ease in reviewing the adjustments, the following are recapi
tulated:

a.
b.

Primary contact wipe: 5/l6" + 0 - I/16"
Arcing contact wipe: 5/16" or greater (gap at primary contacts)

Trip latch wipe:

e.
f.
g.

Trip latch clearance: 1/32" to I/16"
Prop clearance: I/16" to 5/32"
Release latch v/ipe: 3/16" to 1/4"

Primary contact gap:

5-1/4"+5/16" - 1/8"

3/l6" to 1/4" with trip latch resting against

stop pin.

h.
i.
J.

Release latch monitoring switch: maximum clearance 1/32".
Motor and relay switch: maximum clearance I/32"
Interlock switch: maximum clearance 1/32"
Auxiliary switch "a" contacts are closed when breaker primary

Driving and Latching pav/1:

contact gap is 1" or greater.

minimum clearance to ratchet teeth

.015

Latch checking switch contacts make when the gap between the
trip latch and the stop pin is I/16"

Plunger interlock:

11-9/32" plus or minus I/16"

Check all nuts, washers, bolts, cotter pins, and terminal connec0
•^ions

•

for tightness.

OEI-887$5
3:

Inspect all wii'^ins to make sxire that no damage has resulted during

installation^ and test for possible gromids or short circuits.

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

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.
6.

See that any place where the surface of the paint has been dajcaged
is repainted immediately.

Check the trip coil plunger and.the release coil plungef 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. This represents 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.

The opening speed of the arcing contact should be a minimum of 15 feet
per second. This represents the average speed over 3" from the point

when the tip on the movable contact is tangent to the lower surface of
the upper runner.
Control Power Check

After the mechanism has been closed and opened slowly several times with
the maintenance closing wrench and the mechanism adjustments are checked
as described, the operating voltages should be checked at the release
coil, trip coil, and motor terminals. For electrical operation of the
mechanism, 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 nameplate. The following ranges are standards
Closing
Range

260v d-c
125v a-c
25OV a-c

teminals of the coil or motor does

,"P'2G_ified range^ check: the voltage at the source of
power and ixne crop between the power source and breakers

V/hen two or more breakers operating from the same control power source
are required -co close simultaneously, the closed circuit voltage at the

limit^

niotor of each breaker nuist fall within the specified

Electrical closing or opening is accomplished by merely energizing the
closing or trip coil circuit.

Control switches are provided for this

metal-clad unit. It is also possible to trip or close
the breaker manually by pressing the manual trip lever (11) Pig 2 or

tne manual close button (7).

Before the breaker is finally raised into position in the metal-clad

unit, rub a small amount of G-E contact lubricant D50h47 on the silver
ed portion of the breaker studs to form a thin coating for contacting-

purposes.

GENERAL 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 maintenance
scheciule be set up and followed, 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 imr

portant for the successful operation of the breaker.

BEFORE ANY MAIOTENANCE WORK IS PERFORMED, MAKE CERTAIN THAT ALL CON

TROL CIRCUITS ARE OPENED AND THAT THE BREAKER IS REMOVED FROM THE

METAL-CLAD UNIT. DO NOT WORK ON THE BREAKER OR MECHANISM.WHILE IN
THE CK>SED POSITION UNLESS THE PROP AND TRIP LATCH HAVE BEEN SECURELY
WIRED OR BIOCKED TO PREVENT ACCIDENTAL TRIPPING, DO NOT WORK ON THE
BREAKER OR MECHANISM WHILE THE SPRINGS ARE CHARGED UNLESS THEY ARE
SECURED IN THAT POSITION BY THE MAINTENANCE SPRING BLOCKING DEVICE,
Periodic Inspection

The frequency of periodic inspection should be determined by each
operating company on the basis of the number of operations (including
switching),- the magnitude of currents interrupted, and any laiusual

operai^ions which occur from time to time. Operating e2q)erience will
soon establish a maintenance schedule which will give assurance of
proper breaker condition.

On installations where a combination of

fault duty and repetitive operation is encountered, an inspection is
recommended after any severe fault operation. The following instruc-

vions lisc the main points to be included in an inspection and, a num

ber of general recommendations.

GEI-88765 .•
f

'Arc Chutes

It is not necessary to Inspect the arc chutes unless thei*e is evidence
of daniage or if the arc chutes are reraoved for any reason. When in
specting an arc chute, it should be disassembled and the following
points noted;

1.
2,

Scale formed over the sufface of the arc chute must not be removed,
but loose particles collected in the chute should be blown out.
Cracks which have formed in the fins of the arc chute are to be ex

pected in ceramic materials of this type when subjected to the seveii^e

heat of an arc.

These cracks do not interfere with the operation dif

the device in any way and should be disregarded.

It the arc chute has suffered any mechanical injuiy due to dropping
or accidental striking, resulting in the actual breaking off of fins,
replacement of the chute will be necessary. Snail broken comers on
the exhaust end of the chute will not interfere with its perfonsance
and can also be disregarded.

The plastisol flexible covering for the pole pieces (3 & 4) Pig. 16
and the upper mounting support (13) Pig. 16 should be inspected for
breaks in the insulation. If there are holes or breaks in thO inr
sulation they should be repaired or the part replaced.

Arc Chute Removal

The. arc chutes of the 13.8 KV breakers require a mechanical aid to re- < :
move and replace them at general maintenance periods. This can be
accon5)lished by an overhead crane, a portable hoist, or by an arc
chute lifter especially designed for this purpose.

The arc chute lifter (l6) Fig. 19 bolts on the top plate of the breaker,
in line with the chute to be removed, and will lift, transport, and re
lease the chute as necessary.

To use the Arc Chute Lifter proceed as follows:

Remove box barrier (7) Pig. 7.

Bolt angle support (20) Pig. 19 in place on top of breaker.

Place the arc chute lifter over the rear bushing and into the pmpeir

Lower grappling hooks (17) by turning handle (l4) clockwise until
hooks can be placed over lifting bolts (l8) in arc chute.

Turn handle counter clockwise until hooks begin to lift arc chutes

Loosen the two upper supporting bolts (2) Pig. 19 and the one lower

Turn handle of arc chute lifter counter clockwise and move chute

slots.

supporting bolt (9) ?is. 19 using a

wrench.

gently from side to side until both upper and lower supports are
clear.

Move trolly (15) Pig. 19 of the arc chute lifter to the rear.

Tiim handle of arc chute lifter clockwise until arc chute is mat-

ing on the floor and hooks cam be removed.

GEI-88765
T

f
Breaker Contacts

removing the box barrier the movable and stationary primary contacts

^'''^\and the movable arcing contacts can be inspected.

The stationary arc

ing contacts can be inspected only after removing the arc chute assem
bly, as explained under REPAIR AND REPLACEMENT. If the contacts are
burned or pitted, they should be made smooth with a fine file.

After completing inspection of the contacts, check the contact adjust
ments as specified under 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 inspected for any evidence of damage or excessive wear. Lubricate
the mechanism as outlined below, then, using the manual charging wrench,
open and close the breaker several times to make certain that the mecha
nism operates freely throughout its entire stroke.
Check the mechanism
adjustments as specified under ADJUSTMENTS.
Check all terminal connec
tions.

Bushings and Insulation

The surface of the bushings should be kept clean and unmarred to pre
vent moisture absorption.
If the insiilation surface should become
damaged, i t 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 between inspection periods should be wiped off,
and if dampness is apparent, heaters should be installed to insure dryness.

Insulation Test

When insulation has been repaired or replaced, or when 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 27,000 volts RMS will normally indicate whether
the breaker is satisfactory for service.

With the breaker contacts in

the fully open position, apply the high potential to each terminal of
the breaker individually for one minute with all other terminals and

•Che breaker frame grounded.

After high potential tests are made on

organic insxalating materials, these materials should be inspected for
visible leakage current paths, and necessary action must be taken to
replace insulation that may have been affected by moisture absorption.

not handle the

bearings with bare hands as deposits from the skin onto the bearings
are inductive to corrosion. If the bearings are touched, the contami
nation can be removed by washing 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 re

placed,

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 i t is desir

able to leave the bearings in the alcohol for a longer time, an inhibit
ed alcohol such as is used for anti-freeze should be used.

Even then

the bearings should be removed f3?om the alcohol within twenty-four hours.

Esso Anti-Preeze and Du Pont 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
rooms excessive exposure to the fumes is sometimes unpleasant to person

nel .

Washing the bearings in the light oil and draining should follow

immediately, then apply the lubricant.

'•I

GEI-88765

Bea-ri^s that are pressed into the franae or other members such as the

eccentric drive bearings (7) Pig. I5 should not be removed. After reshafi; and inner race the bearing can usually be cleaned
satisfactorily 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 D5OHI5 before reassembling the inner race and shaft.
Rolling Surfaces

A number of rolling and rubbing surfaces in the mechanism have been

lubricated with a baked-on, dry, molybdenum dlsulflde coating.

requires no maintenance and should last the life of the breaker.

This

for magke-blast breakers applied to repepitivb

Ifegne-blast breakers applied to repetitive operation such as switph-^ "
ing arc furnaces and motors should be serviced and maintained ac
cording to the following schedule;

Every 2000 Operation, or Every Six Months - Whichever Comes First ^
1.

Remove the box barriers.

Wipe all Insulating parts clean of smoke deposit and dust
:
with a clean dry cloth. Including the bushings, and the in- ";
side of the box barriers.

All areas In the throat area of the arc chute should be

thoroughly cleaned by using sandpaper.

OSils cleaning should .

be performed any time the arc chute Is removed. The arc chute
fins should not be cleaned. Whenever the arc chute Is re
moved, loose dust and dirt should be blown out before re
placing arc chutes.

Primary Contacts - Inspect the condition of the stationary
contact fingers and movable contact blocks.

burned contacts should be replaced.

(Note;

Badly pitted or

Burned primary

contacts indicate the probable need for arcing contact re

placement).

If the contact surfaces are only roughened or

galled, they should be smoothed with crocus cloth or draw

filed.

After contact dressing the primary contacts should

be greased lightly with D50H47.

Ggl-88765
Arcing Contacts - V/hen the arcing contact wipe is less

than the tniniinuiii specified under ADJUSTMEMTS'^. the contacts should be replaced.

The contacts should be in-

spected for \ineven wear and/or damage using a mirror to
inspect the stationary contacts. Normally it will not
be necessary to remove the arc chutes for this 2000 opera
tion servicing unless inadequate wipe or contact condi
tion 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 possi

ble cleaning or replacement.

Bo not grease the arcing

contacts under any circumstances.

Check the breaker and mechanism adjustments as summar
ized under INSPECTION AND TEST, The necessary read
justments should be made as described under ADJUSTO®NTS»

breaker and operating mechanism should be carefully
inspected for loose huts, bolts, retaining rings, etc.,
all cam, latch and roller siirfaces should be Inspected
for damage or excessive wear.

The buffer blocks and their

retainers on the bottom of the stationary contact siopport
should be inspected for possible need of replacement.

The contacts of the control relay should be inspected for
wear and cleaned if necessary.

10.

Lubricate the breaker operating mechanism in accordance

with the table under LUBRICATION.

Inspect all wiring for tightness of connections and possi
ble damage to insulation,

11,

After the breaker has been serviced, it should be slowly
closed and opened, as described in INSTALLATION, to be
sure there is no binding or friction and that the breaker

contacts can move to the fiilly opened and fully closed
positions. Its electrical operation shovild then be check
ed using either the test cabinet or the test couplers.
B.

After Every 5,000 Operations

In addition to the servicing done each 2,000 operations,
the arc chutes should be removed from the breaker and dis

assembled to permit a detailed inspection of insulation,
blow-out coils, arc runners and assemblies which can be
come contaminated by arc products.

. ^

GEI-88765

The blov/-out coils should be carefully examined and if the
insulation has been cracked^ shrunk or eroded from arc action
and heat so that the turns of the coil^ are not fully insu
lated from each other, the coils should be replaced. All
connections should be checked for tightness.

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.

Check,the stationary arc contacts to assure that the arcing
contacts are in good condition and that their connections
are tight.

Insulating material that is carbonised and cannot be satis
factorily cleaned should be replaced.

Any parts damaged or severely buraed and/or eroded from arc
action should be replaced.
NOTE; Pine cracks may develop in 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 sec
tions breaking completely off. Snail brhken comers on the
exhaust end of the arc chute will not interfere with its
performance and can also be disregarded.

The cup bearing and the contacts ring at the hinge point of

the contact blade should be disassembled, inspected, cleaned,
and relubricated with G-E contact lubricant D50H47. The con
tact ring should be inspected for wear and replaced when re

duced in thickness to less than 1/32".
C.

Every 10,000 Operations or*Approximately Every Five Years 'vrhichever Comes First.

At this time the breaker should be given a general overhaul
and all excessively worn parts in both the mechanism and

breaker replaced. Such wear will usiially be indicated when
the breaker cannot be adjusted to instruction book tolerances.
This overhaul and inspection is more detailed and will re
quire disassembly of mechanism and breaker operating parts,

All roller and needle bearings in the operating mechanism
should be disassembled, cleaned, and repacked with Q.E.
lubricant D50H15 as described under LUBRICATION.

fxEI-88765 .

The stationary.primary contact fingers should be disassembled
and the silver-plated pivot area of the contact and contact si'Th

port cleaned and lubricated with G-E lubricant D50H47.

The^ breaker and operating mechanism should be serviced as des
cribed for every 2,000 operations, and properly adjusted before
being put back into service.

Magne-blast breakers, applied to repetitive operation such as capaci
tor switching should be serviced and maintained according to the preceeding recommendations, and in addition, shoxild have items lAl, li^,
and 1A3j repeated at 500 operation intervals.
TROUBLE SHOOTING

Failure of a breaker to operate properly will generally fall within four .

general classes; failure to trip, failxare to close or latch closed, clos
ing springs will not recharge, and overheating. The following is a
brief outline showing particular types of distress that might be encoun
tered, together with suggestions for remedying the trouble;
' "
Failure to Trip

——i——

1.
2.

.n I

Mechanism binding or sticking caused by lack of lubrication.
REMEDY:

ygsp.

Lubricate complete mechanism.

Mechanism binding or sticking caused by being out of adjustment,

REMEDY:

Check all mechanism adjustments, latches, stops, auxiliary

devices, etc., in accordance with section on ADJUSTMENTS.

Examine

latch and roller surfaces for corrosion.

Damaged trip coil.
REMEDY; Replace damaged coil.

Blown fuse in urip circuit.
REMEDY;

Replace blown fuse after determining cause of failure.

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

Damaged or dirty contacts in trip circuit.
REMEDY:

Recondition or replace contacts.

Failure to Close or Latch Closed

Mechanism binding or sticking caused by lack of lubrication.
REMEDY; Lubricate complete mechanism.
2.

7^
20

Damaged or dirty contacts in control circiiit.
REMEDY: Recondition or replace contacts.

GEI-88765
3.

Blown fuse in closing circuit.

REMEDY: Replace blown fuse after determining cause of failure.
Faulty connection in charging circuit.

REMEDY;

Repair broken or loose wires and see that all binding screws

are tight.
Overheating

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

REMEDY:

or replace burned and pitted contacts. (Contacts
should beRecondition
reconditioned
very carefully and only when absolutely

necessary.)
2.

Contacts not properly aligned or adjusted.
REMEDY; Check all adjustments in accordance with section on ADJUST
MENTS,

•

Breaker kept closed or open for too long a period.
REMEDY: Operate breaker more often to wipe contacts clean.

Replace

contacts if necessary.

Overloading.
RSEDYs Replace breaker with one of adequate rating for present or
future loadj or re-arrange circuits so as to remove excess load.

Primary connections of inadequate capacity.
REMEDY;

Increase size or number of conductors or remove excess cur

rent.

Loose connections or terminal connectors.
REMEDY;

Tighten.

Ambient temperatiire too high.

REMEDY;

Relocate in a cooler place or arrange some means of coollnig,

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 Instal

lation on parts of the breaker that are most subject to damage or wear.
IMPORTANT; UPON COMPLETION OP ANY REPAIR WORK, ALL BREAKER AND MECHA
NISM ADJUSTMENTS MUST BE CHECKED. Refer to the section on INSTAU«ATXGN,

paying particular attention to ADJUSTMENTS and FINAL INSPECTION.

asi-88765

Arc Chute (To Inspact or replace bloxi-out colls)
IB)

To reuove an arc chute, first open the breaker and remove the box bar

rier {7)i Pig. 7.

Loosen the two upper supporting bolts (2) Fig. 19

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 Pig. 19.

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

Remove the assembly bolts (2,6,7,9,10,12, and 15), Pig. 16.

Remove the side brace (l4), and rear brace (5), the upper pole
pieces (3), and the lower pole pieces (4), Pig. 16.

To remove the upper moimting support (13), Pig. 16 remove the assem

bly bolts (1 and 11), and the upper connection bolt (8) Pig. 18.

4. Remove the assembly bolt (18) to remove the lower brace (8) Pig. 16.
5.
6.

Remove the lower mounting support (16) by removing the assembly
bolts (17) Pig. 16 and the connection nut (7) Pig. 18.
At this point, the fiber side shields (4), Pig. I8 and the upper

arc runner assembly (2) can be removed.

7«

Further disassembly of both the upper and lower arc runner assem^

blies can be done by removing the various screws and 1/4" assembly

bolts (not illustrated) as shown in Pig. 17.

The arc chute sides (6) Pig. 17 can also be separated for inspec
tion.

Reassemble the arc chute in the reverse order.

The following items

should be noted during reassembly:

Equally space the fins of the arc chute sides before bolting together,

The gap between the fins at the rear of the arc chute should be

3/64" to 3/32" measured at least 1" in from the back end of the arc
chute (see Pig. 21).

Check to insure that electrical connections to the blowout coils
are tight.

T^en reassembling the arc runner assemblies, check that the spacers
(1 and 10), Fig. 17, are correctly installed.

GEI-88765

• 5.

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.

6, Make certain that the electrical connections are tight.
To reassemble the arc chute to the breaker, proceed as follows;

Rest the lower mounting support (8) on the arc chute mountins brack

et (7) as shown in Fig. 19.

Slide the arc chute forward and lift it slightly to engage the sup-

po^t ^)^^lts
3.

*Fig. 19, in the slots of the upper mounting sup-

Check the spring baffle (ll). Fig. 22, to assure that it closes the
pp between upper- insulation (19). Fig. I6 and the back of the con.tact support (4), Pig. 22.

Tighten the supporting bolts (2 and 9) Fig. 19. These bolts serve

as both the electrical and mechanical connections between the bush
ing and the arc runners.

Check that the movable arcing contact (4), Pig. 19, has clearance

to the upper arc mmner (2) Pig. 17 without touching.

Contacts

Open,the breaker and remove the box barrier and arc chute as previously
described.

To remove the contacts, proceed as follows:

Stationary Arcing Contacts (10), Pig. 22.

Disconnect the contact braids from the contact fingers by remove
ing two bolts (8), Pig. 22.

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 (o).
5.

Reassemble in the reverse order.

GSI-88765

Stationary Priraary Contacts (9)^ Fig. 23
1.

Compress the contact spring (6),

Remove spring and spring guide (l).

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§

Apply a thin coating of D50H47 grease on the hinged edge of the

finger (9) then place it on the contact support 1[7) so that it

Is retained by stop plate (8).

Open spring compressor (3) and assemble spring guide, spring and
spring compressor (Pig. 23A).

Turri nut (2) in clockwise direction to compress contact spring
(pig. 23B). Hold spring firmly In yoke on spring compressor to
prevent spring from slipping out of the compressor,

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 sprites
guide In cutout In primary finger (Plg. 23C).
5.

Hold spring assembly firmly In place and remove spring compressor. (

Movable Arcing Contact (7), Fig. 24,

Remove the assembly bolts (8).

Reassemble In reverse order.

Movable Primary Contacts (5), Pig. 24 (1200 Amp. Breaker)
1.

Remove the nuts from assembly bolts (6).

Remove the primary contacts.

Reassemble In reverse order.

(2000 Amp. Breaker)

1,.

Remove the nuts from assembly bolts (6).

Remove the connection bar (9).

Remove the cup bearing (3).

GEI-88765

Spread the contact arms (4) sind remove the primary contacts (5).

Reassemble in the reverse order.

Contact Blade Assembly (4> 5, 7) pig. 24
1.

Remove the connection bar (9).

Remove the cup bearing (3) and the pin (ll).

3» When reassembling, first insert the piston assembly (IQ), into
the booster cylinder and reassemble the cup bearing (3).

4.
P.

Replace pin (ll), aind connection bar (9).

After disassembly and reassembly of any contacts, check all contact
adjustments as described under ADJUSTMENTS.

;

Bushings

IMPORTANT-. DO NOT REMOVE ALL SIX BUSHINGS AT ONCE. 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 fa- i;
cilitate installation of the breaker in the metal-clad ixnit. It is,
therefore, 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 direc
tions, so that it may be reinstalled 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 4
placing the breaker in a de-energized spare metal-clad unit before
tightening the biishing mounting bolts.

This must be done before the

arc chutes are reinstalled.

To replace the bushing, proceed as follows:
Rear Bushing

Open the breaker and remove the box barrier and arc chutes as al-v:,
ready described.

Remove the upper and lower horizontal barriers (l8 and 20), Pig. 7,

Remove the four bolts at the mounting flange of the rear bushing

Referring to Pig. 23, disassemble the primary contact springs

being removed and lower the bushing assembly.
as. previously described,

Disassemble the spring retainer (4) by removing mounting bolts (5)

a-si-88765
V

•

Referring to Pig. 22, disassemble the contact support (4) and arc
chute mounting bracket (2) by removing two bolts (3).

Reassemble in the.reverse order.

The arc chute mounting bracket

(2) is not symmetrical and must be assembled correctly to orient

the chute properly on the breaker. The longest projection of the
bracket should be toward the lower end of the bushing.
Front Bushing

Open the breaker and remove the box barrier and arc chutes as al
ready described.

Remove the upper and lower horizontal barriers (l8 and 20) Fig. 7.

Remove the connection bar (9), Fig. 24, cup bearing (3), and pin
vllJ.

Remove the four bolts at the mounting flange of the front bushing
being removed, and lower the bushing.

When reassembling, first mount the bushing and assemble the cup '
bearing (3) contact arm (4), and replace pin (11). The contact
surfaces at the hinge point of the contact blade and bushing
should have a thin coating of D50H47 grease.

Check all contact adjustments as outlined under ADJUSTMENTS.

INTERLOCK SWITCH

To remove the interlock switch (3)f 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 ADJUSTMENTS.
LATCH CHECKING SVJITCH

To remove the latch checking switch (7), Fig. 10 (when furnished), re

move the two mounting screws and disconnect the lead wires. Reassemble
in the reverse order and check the switch adjustments as explained un
der ADJUSTMENTS.

MOTOR. RELAy AND LIGHT SWITCHES

The three switches are mounted in tandem as shown in Fig. 6.
1.

Remove the opening spring per instructions below.

2. Remove (2) mounting bolts (l4) from switch bracket (15).
3.

Remove the (2) mounting screws of the lower switch.

Remove the (2) mounting screws of the center switch.

GEI-88765

Remove the (2) lY.cjriting screws of the upper switch.

Disconnect the lead wires of switch to be replaced.

Reassemble in the reverse order and check switch adjustments as
described under ADJUSTMENTS.

trip' shaft and latch

Remove latch checking switch arm (10) Pig. 11 (when supplied).

Remove cotter pins on both ends of the shaft (12).

Remove set screw in latch (11).

Remove trip coil linkage bolt (6).

Place a block between the latch and frame (either side) and drive

shaft until the latch is free of the key.

6. Remove key and all burrs that may be raised around the keyway on the
shaft.

Burrs will scar or shave the Teflon bearing surfaces if they

are not removed.

Reassemble the parts in the reverse order.

Be sure the latch spring

is properly installed and the latch is aligned in the center of the
latcn roller. Check latch adjustment as described under ADJUSTMENTS.

TRIP LATCH ROLLER BEARING

Remove (2) cotter pins at ends of shaft (8) Pig. 12.

Partially remove shaft out right side of frame until latch roller
(0) is free.

Reassemble in reverse order with proper spacing of washers.
latch roller rotates freely.

Be sure

CLOSING LATCH.

Remove cotter pins at both ends of latch shaft.(19) Pig. 6.

Remove spring and paddle (16) Pig. 6.

Remove set screws from latch (3) Pig. 6.

4. pve shaft (l4) to left (away from frame) by tapping lightly on the
^nsiae end 01 shafo.

IS free.

Hptate''Shaft*and continue tapping until shaft .

Shaft will push outside needle bearing from housing.

asi-88765
V

Reassemble in reverse order putting bearing into frame last. Use a
small piece of tubing or pipe when inserting bearing to assure
proper alignment.

Check latch adjustments as described under ADJUSTMENTS.

MOTOR SUPPORT

To remove motor support (8) Pig. 15, first remove the latch spring.
(16) Pig. 6.

Remove the retaining ring (9) Pig. 15 and link (lO).

Remove motor leads from the terminal board.

Remove six 3/8" bolts (1) Pig. 15 on bottom and one 3/8" bolt on
the right side (not shown).

Remove four mounting bolts from motor (not shown).

Remove the retaining ring (7) from the eccentric (2) Pig. 15,

Reassemble all parts of the motor support In the reverse order and
re-allgn It properly as described under DRIVINQ PAWL ADJUSTMBIOTS.

CAM

Remove 2 set screws from ratchet wheel (3) Pig. 3 and remove wheel

Remove 2 set screws from cam (12) Pig. 1.

Remove prop reset spring (10) Pig. 2.

Remove 2 set screws from cam (l6). Pig. 5> and move cam to the

from main shaft (8).

right on the shaft as far as It will go. Slide the shaft to the
left until key is fully e:q)osed. Remove key and check shaft for
burrs.

Remove shaft out left side of frame.

Reassemble in reverse order using the correct number of washers and
spacers to properly locate the parts.

Rotate the mechanism through a closing operation using the mannai
charging wrench. Check the location of the cam follower (6), Pig.

5t on the cam (l6).
alignment.

If necessary, move the cam to correct the

Complete the closing operation and check the location

of the prop pin (13), Pig. 5 on the prop (l4).
proximately centered.

•^28

It should be ap

GEI-88765
TRIP COIL

To replace the potential trip coll (2), Fig. 11 proceed as follows;
1.

With the breaker in the open position, remove the two moimting bolts
IJ J •

Remove upper support (l) and spacers.

Cut wires at the butt connectors and remove coil.

When jireplacing the coil be sure to assemble the correct fiber spa-

cers at the ends before bolting support (1).

Adjust coil location to allow approximately 1/4" of armature travel
before latch starts to move.

Butt connect wires and check operation of solenoid .electrically and
mechanically.

SPRING RELEASE COIL

To remove the spring release coil (5), Pig. 6 proceed as follows:
1.

Block the closing springs as described in INSTALLATION.

Remove the left hand closing spring as described in CLOSING SPRINGS
below.

Remove two mounting bolts (17)^ coil support (l8), and spacers.

Cut wires at the butt connectors and remove coil.

Replace the coil and the correct number of fiber spacers before
bolting support.

Butt connect wires and check that the armature is not binding.
Check coil for electrical operation.

CLOSING SPRINGS

The closing springs (6) Pig. 3 can be removed as follows:

Charge the springs with the manual charging wrench and apply the
spring blocking device as described in INSTALLATION.

Discharge springs by pushing manual close button (7) Pig. 2.

c-EI-88765

Rotate cam shaft (SJ Pig. 3 oy usin^ the manual charging v/rench
until the gap bef.veeri c-he spring (6) and the bearing block (10)

is 2 inches or more.

lift both springs until they clear the lower supports, then pull
forward and down until the top supports are free.

Either discharge the opening springs by pushing the manual-trip
lever or block the opening springs with a suitable blocking device.

OPENING SPRINGS

To remove the opening springs (9) Pig. 3 proceed as followsj
1.

Charge- and block the closing springs as described imder INSTAIILATION.

Push manual trip lever (11) Fig. 2 to.be sure the opening springs

•

are fully discharged.

3.
4.

Remove upper pin (12) Pig. 3 and lower pin (11).
After reassembling springs check the primary opening as described
under PRIMARY CONTACT GAP.

OPENING BUFFER BLOCK

The opening buffer block is essentially to limit the travel of the con-

tact arm.

To remove the buffer block assembly remove bolt (16) Pig. 14.

To disassemble the buffer block (18) remove the two bolts (17).

If it

is necessary to remove the buffer block on the supporting members the
block will have to be adjusted as follows. Remove operating rod pin

(11) Fig. l4, and place contact arm so that the primary gap is at the
maximum setting. Add or remove shims (19) to allow 1/16" to 3/16" clearance
between the buffer and the contact arm. Lower contact ami to rest
against the biiffer block and check the clearance from the movable

arcing contact (7) to the booster cylinder.

mum of 1/4" clearance at the top and side.

There should be a mini

Re-assemble pin in contact

arm after adjustments are made.
RENEWAL PARTS

It is recommended that sufficient renewal parts be carried in stock

to enable the prompt replacement of any worn, broken, or damaged
parts. A stock of such parts minimize service interrupting caused by
breakdowns, and saves time and expense. When continuous operation is
a primary consideration, more renewal parts should be carried, the
amount depending upon the severity of the service and the time re
quired to secure replacements.

GEI-88765

r~^-

]1enev;al parts v;h:Lch are furnished may not be Identical to the original
partsj since.improvements are made from time to time. The parts which
are x'urnished;. however, will be interchangeable.

The Renewal Parts List covers the following types of breakers.
AM-13.8- •750-2C
AM-13.8. •750-2CR
AM-13.8- •750-2CB
AM-13.8- •750-2CBR
AM-13.8- 750-2H
AI4-13.8- •750-2HR
AM-13.8- •750-2HB
AM-13.8- 750-2HBR
AM-13.8- 750-3C
AM-13.8- 750-3CR
AM-13.8- 750-3CB
AM-13.8- 750-3CBR
AM-13.8- 750-3H
AM-13.8- 750-3HR
AM-13.8- 750-3HB
AM-13.8- 750-3HBR
NOTE:

1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A
1200A

&
&
&
&
&
&
&
&
&
&
&
&
&
&
&

2000A
2000A
2000A
2000A
2000A
2000A
2000A
2000A

2000A
2000A
2000A
2000A
2000A
2000A
2000A
& 2000A

The listed terms "Right" and "Left" apply when facing the mechan-ism end of the breaker.

ORDERING INSTRUCTIONS

Always specify the complete nameplate data of both the breaker at^
the mechanism.

Specify the quantity, catalog number (if listed), reference, number^
(if listed), and description of each part ordered, and this bullet
tin nutnber.

Standard hardware, such as screws, bolts, nuts, washers, etc., is;
not listed in this bulletin. Such items should be purchased lo
cally.

For prices, refer to the nearest office of the General Electric
Company.

-S0703
PARTS REC0r>lI'1ENDED FOR NORMAL I4AINTENAMCE

\Tln the tabulation below are listed the parts of those breakers which are
usually recommended for stock for normal maintenance.

Catalog No. for 'gzpe AM-13.a-750'

24
24
24
24
24
24
24
24
6
6
6

All
All
All
All
All
All
All
All
All
»

B
All
All
All
B
All
All

All
All

All
All
All

.All

0231B0708G001
O23IBO708GOO7
O263BO292POO2
O898BO275GOO2
O898BO275GOOI
0456AO336POOI
0414A0195P002

•3

Design

'U6.
Req'd.

O28IBO708OOOI
028IBO703QOO7
0263B0292P002
G398B02750O02
0898BO275GOOI
0456AO336POOI
04i4A0195P0O2

04i4a0116P088

0414A0116P088

0898B0224G005
0898B0224G004
0836001520004
OO6509787POOI
0121A5964P001
O236CO79IPOO8
005591644P007
006591644POOS
O836COI55OOO4
C836C0155G005
0215x03430049

O236CO79IOOO4
0236007910001
0236CO79OGOO9
OO6509787POOI
0121A5964P001
O236CO79IPOO8
0137A9164P003
0137A9164P004

0802B0742a003
0802B0742Q004
0213x03430046

0105C9593P001
0105C9393P002
0105C9393P003
0137A7575P0C4
0137A7575P001

0137A7575P001

OIO8BI97SGOOI
0137A7575P005
0137A7575P002

0137A7575P005
0137A7575P002

0105C9393P001
0105C9393P002

01O5C9393POO3
0137A7575P004
OIO8BI978OOOI

3
3
3
3
3

Description

Operating Rod
Operating Rod
Booster Cylinder

Throat Insulation (Left)

Throat Insulation (Right)

Lower Runner Insulation

6
3
3
3

Lower Shield

Insulation Plate

Flexible Connector (Left)
Flexible Connector (Right)
Arcing Contact Assembly

24
24
6
6
3
3
3

Primary Contact Finger Springs
Primary Contact Finger Springs
Primary Contact Finger
Movable
Movable
Movable
Movable

Primary Contact
Primary Contact
Arcing Contact
Arcing Contact

Tube and Piston Assembly
Motor
Motor
Motor

Relay
Relay
Relay
Relay
Relay

0137A9252P001
0161A4241P001

Closing Latch Spring

0137A9252P001
0161A4241P001

All

OI6IA5909FOOI

OI6IA5909POOI

Prop Spring
Driving Pawl Spring

OO6174582GOOI

0061745820015
0061745820002
0061745820010
0061745B20014
OO627507OGOOI
OO627507OQOO2
0061745820001

0061745820015
0061745820002
0061745820010

0061745320014
OO627507OGOO2
0456AO866POO5

0061745820001
0061745820015
0061745820002
0061745820010
0061745820014
0062750700001
OO627507OGOO2
0061745820001
0061745820015
0061745820002
0061745820010
0061745820014
OO627507OQOO2
0456AO866POO5
0456AO866POO6
0137A91920003

115 V-ac
230 V-ac

220 & 250 V-dc
48 V-dc
110 & 125 V-dc
220 & 250 V-dc

0456AO866POO6
0137A9192G003

10
10

Design

All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All
All

Potential Trip Coll
Potential Trip Coil
Potential Trip Coil
Potential Trip Coil
Potential Trip Coll
Potential Trip Coll
Potential Trip Coll
Spring Release Coll
Spring Release Coll
Spring Release Coll

Spring Release Coll
Spring Release Coil

110 & 125 V-dc
220 V-dc

250 V-do
115 V-ac
230 V-ac
24 V-dc
48 V-dc
110 & 125 V-dc
220 V-dc

250 V-dc
115 V-ac

230, V-ac

;^ring Release Coil - 48 T-dc
^itchj Normally Qpen
Switch^ Normally Closed
Auxiliary Switch

Latching Pawl Spring

All except breakers with "B" suffix.

^ Quan. (2) relays required on special control circuits. Check breaker and connection
alagram.

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(GE) Magne Blast Breakers 5k V Vol 2 Of 3

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