BARTON S 274A, 335A, 335P, 335T, And 338E Pneumatic Transmitters Controllers Brochure
User Manual: BARTON s 274A, 335A, 335P, 335T, and 338E Pneumatic Transmitters and Controllers Resource Library
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MEASUREMENT SYSTEMS
BARTON®
Pneumatic
Transmitters and Controllers
Models 274A, 335A, 335P, 335T, and 338E
The Barton®pneumatic instrument product line consists of
Pneumatic Transmitters and Indicating or Recording Controllers.
All are designed to meet the most stringent and demanding
requirements for Oil & Gas Production, U.S. Navy Shipboard,
and Process Plant applications.
The heart of the DP-driven instruments is the rugged Barton®
Differential Pressure Unit (DPU) – featuring a time-proven
liquid-filled bellows and torque tube design. Recording
and Controlling models are also available with Pressure
or Temperature actuators.
Pneumatic Transmitters
(Standard DP and Linear-with-Flow)
• Models 274A - DP Transmitters
••Actuated by Barton’s®M199
••Rugged, Weatherproof, Non-corrosive Case
••Continuous Purging (pilot valve and nozzle exhaust inside)
••Operation Span Continuously Adjustable (100 - 20%)
••Adjustable Suppression (up to 80% of range)
••Large Valve Relays (no need for secondary booster)
••Span Continuously Adjustable (down to 20% of range)
••Air Consumption (at balance condition) 0.05 scfm max.
Actuating Units
• Barton®Pneumatic Transmitters are actuated by the M199
Differential Pressure Unit (DPU) which is also available in a
NACE certified version.
Cases
• Barton®Pneumatic Transmitters are housed in a rugged,
weatherproof case especially suited for use in corrosive fume
environments. Since the pilot valve and nozzle exhaust
inside the case, continuous purging is achieved.
Transmitting Unit
• Changes in DP are transmitted mechanically to the flapper,
which covers a small constant-feed nozzle. Any change in
the position of the flapper will instantly change the nozzle
pressure, which in turn controls the action of the 2-valve
balanced relay to increase or decrease the output air pressure.
A calibrated bellows assembly actuated by the output
pressure serves to reposition the flapper mechanism and
restore a state of equilibrium - in this manner, output air
pressure varies in direct relation to the differential pressure
applied to the instrument, or in direct proportion to the
flow-rate. The relay is not affected by changes in output
pressure and this makes it possible to maintain practically
constant nozzle pressure at any output pressure.
Operating Span/Suppression
(Linear-with-DP units only)
• The operating span is continuously adjustable from 100-
20% of the DP range. Thus a unit with a differential pressure
range of 0-100" w.c. can be adjusted to provide a 3-15 PSI
(207 mbar-1 bar) output signal (direct or reverse) for any
span from 0-20" w.c. to 0-100" w.c. (0-50 mbar to 0-248
mbar) range. The operating span can be shifted anywhere
within the range of the differential pressure unit to introduce
suppression up to 80% of the range.
M274A
M335A
M338E
2
Specifications
• Model 274A
••Sensitivity: 0.05% of DP range
••Operating Span: Continuously
adjustable down to 20% of
standard DP range
••Max. Suppression: Continuously
adjustable up to 80% of full
DP range
••Air Consumption:
0.05 scfm maximum
••Linearity of output signal to
input differential: DP span to
150 PSI (10.3 bar) (15 PSI/1 bar
for M274A), +/- 0.5% of full
range output pressure
••DP span above 150 PSI (10.3 bar)
(15 PSI/1 bar for M274A), +/- 0.75%
of full range output pressure
Pneumatic Controllers
(Indicating and Recording)
• Barton®Pneumatic Controllers are
available in indicating or recording
models for control of DP, pressure,
or temperature variables.
Cases
• Barton®Pneumatic Controllers are
housed in a rugged, weatherproof
case, finished with a black epoxy
resin paint – designed for hostile
outdoor environments. Optional
stainless steel case and door versions
are available for recorder models.
Indicating Controllers
• Models 335A - Indicating DP
••Barton®Pneumatic Indicating
Controllers are actuated by the
Barton®M199 DPU. They can
measure, indicate, and control
DP flow, or liquid level.
• Models 335P/335T - Indicating
Pressure/Temperature
••Barton®Pressure and Temperature
Indicating Controllers are actuated
by a wide selection of capsular
bellows or helical bourbon tube
static pressure elements, and liquid
or mercury-filled temperature
systems to indicate, measure,
and control a variety of pressure
or temperature processes.
Recording Controllers
• Models 338E - Recording DP
••Barton®Pneumatic Recording
Controllers measure, record, and
control DP, flow, and liquid level.
The controlled variable is recorded
on a standard 12-in. circular chart.
The setpoint is indicated by a red
pointer on the chart. An additional
pen may be added to record two
additional pressures or temperatures.
These instruments are actuated by
the Barton®M199 (338E) DPU.
Control Actions
(All Controllers)
• Gain (proportional) from 1 to
400% (direct or reverse) (P)
• Gain (proportional) plus Integral,
adjustable from 0.02 to 70 repeats
per minute (P+I)
• Gain (proportional) plus Integral plus
Derivative, adjustable from 0 to 20
minutes (P+I+D)
• Differential Gap (direct or inverse),
adjustable from 2 to 80% (Differential
Gap is not available in recorders)
Control Modes
(All Controllers)
• Gain Control (proportional)
••Increases or decreases the output
air pressure in proportion to the
deviation of the measured value
from the control point.
• Integral Control
••Continuously adjusts the output air
pressure to eliminate “offset” and
maintain the process at the desired
control point.
• Derivative Control
••Acts to augment corrective action
at a rate proportional to the speed
with which the measured value is
moving away from the control
point. This type of action is used
to minimize the magnitude of
“offsets” as quickly as possible.
• Differential Gap Snap-Acting
••Causes the air output pressure
to change from 0 to 20 PSI
(0 to 1.4 bar) or vice versa, at
the edges of a span (differential
gap). Within the span the output
air pressure does not change until
the other edge of the differential
gap is reached.
• Direct or Reverse Controller Action
••May be selected for any mode of
control. Direct-acting controllers
increase output pressure for an
increase in the controlled variable.
Reverse-acting controllers decrease
output pressure for an increase in
the controlled variable.
Specifications
• Performance
••Pilot Capacity (non-bleed relay):
3.0 SCFM with less than 0.1 SCFM
bleed rate @ 9 PSI output
3
MEASUREMENT SYSTEMS
••Air Output: 3-15 PSIG
(207 mbar - 1 bar) 6-30 PSIG
optional (414 mbar - 2.1 bar)
• Temperature Limits
••(Ambient):
-40°F/°C to +180°F (+82°C)
••Accuracy of Indication:
(335A/335P/335T/336C): +/- 1.0%
••Accuracy of DP Recording (M338E):
0-20-in. w.c. to 0-349-in. w.c.
(0-50 mbar to 0-867 mbar)
+/- 0.5% of full scale DP,
0-350-in. w.c. to 0-50 PSI
(0-869 mbar to 0-3.4 bar)
+/- 0.75% of full scale DP
••Accuracy of Temperature Recording
(M341E): up to +300°F (+150°C)
+/- 1.0% of full scale
••Accuracy of Pressure Recording
(M340E) (typical w/Ni-Span-C):
Helical & Bellows Elements
+/- 1.0% of full scale
• Actuator
••Model 335A (Indicating):
M199 DPU
••Model 335P (Indicating):
Pressure Elements
••Model 335T (Indicating):
Thermal Elements
••Model 338E (Recording):
M199 DPU
••Model 341E
(Temperature Recording):
Thermal Elements
••Model 340E
(Pressure Recording):
Pressure Elements
• Temperature Elements
••Type: Precision wound spiral,
mercury-filled, case-compensated
••Bulb: Stainless Steel, flexible neck
••Capillary: Stainless Steel,
stainless armor
••Socket: 4 to 6-in.
••Ranges: 0-100°F (40°C)
0-120°F (50°C)
0-150°F (65°C)
0-200°F (95°C)
0-300°F (150°C)
• Pressure Elements
••Type: Precision wound helical or
capsular bellows
••Ranges: 0-30-in. Hg vacuum to
0-30,000 PSI (0-14.7 PSI/1 bar
to 0-2,068 bar)
••Receiver Element: 3-15 PSI
(207 mbar to 1 bar)
• Materials
••Helical: Ni-Span-C, SST, or Monel
(6,000 PSI/414 bar maximum)
••Bellows: Stainless Steel
Optional Accessories
• The 2-Way Auto-Manual Bypass
(indicating or recording controllers)
provides the operator with a
convenient means for shutting off
controller air to a valve and for
manually positioning the valve. The
two positions offered in the bypass
are: MANUAL and AUTOMATIC.
Bumpless transfer can be achieved.
• The 4-Way Auto-Manual Bypass
(recording controllers only) is a
separately mounted sub-panel used
for shutting off the controllers and
for manually positioning the valve.
The four positions offered are:
SERVICE, TEST, MANUAL, and
AUTOMATIC.
Ordering
When ordering, please specify the
following items:
Transmitters:
• All Models
••Model Number
••Air Supply: 20 PSI (1.4 bar)
output 3-15 PSI (207 mbar - 1 bar)
••Air Connections: 1/4-in. NPT
••Mounting: Pipe or Wall
• DPU Models
••Housing Pressure Rating (SWP)
••Housing and Bellows Materials
••Process Material
Contacting Bellows
••Differential Pressure Range
Controllers:
• All Models
••Model Number
••Controller Action: Gain
(direct or reverse), Gain+Integral,
Gain+Integral+Derivative,
Differential Gap (direct or reverse)
••Mounting: Pipe or Wall
••Options: Remote Set Chassis, 2-
way auto/manual bypass, and 4-
way auto/manual bypass
• DPU Models
••Housing Pressure Rating (SWP)
••Housing and Bellows Materials
••Process Material
Contacting Bellows
••Differential Pressure Range
• Indicator Models
••Scale Type: square root,
uniform, etc.; graduations
• Recorder Models
••Pressure Elements: Range, Material
••Pens: Disposable or bucket
••Chart Drive: Type and rotation
••Thermal Systems: Range, capillary
length, Class, Socket [length
below threads]
••Charts: (In-stock std.)
0-100/-150/-200/-250/-300/-500,
marked for 24 hr. rotation.; special
order available, with min. quantity
of 5 boxes)
NORTH
AMERICA
1.800.654.3760
ms-us@c-a-m.com
ASIA
PACIFIC
65.6737.0444
ms-asiapacific@c-a-m.com
EUROPE, MIDDLE EAST
& AFRICA
44.1243.826741
ms-uk@c-a-m.com
HOUSTON HEAD OFFICE: 281.582.9500 • www.c-a-m.com/flo
USA: Houston, TX • Corpus Christi, TX • Kilgore, TX • Odessa, TX • Dallas, TX • Tulsa, OK
Duncan, OK • Denver, CO • Bakersfield, CA • Shreveport, LA • Lafayette, LA
Houma, LA • Pittsburgh, PA • Laurel, MS • Dunbar, WV • Casper, WY • Charleston, WV
CANADA: Calgary, AB • Edmonton, AB
INTERNATIONAL: Aberdeen, Scotland • Beijing, China • Bognor Regis, UK
Dubai, UAE • Hassi Messaoud, Algeria • Kuala Lumpur, Malaysia • Singapore
Formerly: NuFlo Measurement Systems • Barton Instrument Systems • Caldon, Inc.
MEASUREMENT SYSTEMS
MEASUREMENT SYSTEMS
DPU-PNE NF00044 0612
WARRANTY-LIMITATION OF LIABILITY: Seller warrants only title to the product, supplies, and materials and that, except to software, the same are free from defects in
workmanship and materials for a period of one (1) year from the date of delivery. Seller does not warranty that software is free from error or that software will run in an
uninterrupted fashion. Seller provides all software “as is”. THERE ARE NO WARRANTIES, EXPRESSED OR IMPLIED, OF MERCHANTABILITY, FITNESS OR OTHERWISE WHICH
EXTEND BEYOND THOSE STATED IN THE IMMEDIATELY PRECEDING SENTENCE. Seller’s liability and Buyer’s exclusive remedy in any case of action (whether in contract, tort,
breach of warranty or otherwise) arising out of the sale or use of any product, software, supplies, or materials is expressly limited to the replacement of such products,
software, supplies, or materials on their return to Seller or, at Seller’s option, to the allowance to the customer of credit for the cost of such items. In no event shall Seller
be liable for special, incidental, indirect, punitive or consequential damages. Seller does not warranty in any way products, software, supplies, and materials not
manufactured by Seller, and such will be sold only with the warranties that are given by the manufacturer thereof. Seller will pass only through to its purchaser of such
items the warranty granted to it by the manufacturer.
Weights
Approximate Gross Weight (lbs/kg)
Material/Safe Working Pressure (PSI)
Aluminum Forged Steel Forged SST
Model 1000 2500 4500 6000 1000 3000 6000
Transmitters
274A 30 51 52 54 42 52 54
(14) (23) (24) (24) (19) (24) (24)
Controllers
335A 30 51 52 54 42 52 54
(14) (23) (24) (24) (19) (24) (24)
338E 47 68 69 71 59 69 71
(21) (31) (31) (32) (27) (31) (32)
