BULLETIN DB-851
PART #K796381
PRESSURE TRANSDUCERS
U.S. GAUGE
PMT PRODUCTS
U.S. GAUGE PMT PRODUCTS 820 Pennsylvania Blvd., Feasterville, PA 19053 U.S.A. TEL: (215) 355-6900 FAX: (215) 355-2937 www.ametekusg.com
EFFECTIVE: 5/99 SUPERSEDES: 5/95
Model 851 Series Pressure Transmitter
FEATURES
PMT QUALITY COMMITMENT
AMETEK’s commitment to quality in
pressure measurement technology
is unequalled in the industry. Behind
every Model 851 transmitter are 20
years of piezoresistive sensor chip and
stainless steel diaphragm/oil isolation
technology. Over these years AMETEK
has developed and perfected test
methods and quality checks to ensure
that every transmitter will operate within
specification in tough environments
for years of service. The most advanced
automated test systems in the industry
are used to characterize and final test
every transmitter.
In addition, every transmitter goes
A miniature, low-priced full-
featured transmitter—just 1 lb.
(450 grams)
All welded 316 stainless steel
construction and wetted parts
(no aluminum)
Ranges from 0-3 (0.2 bar) to
0-5000 psig (350 bar)
+0.25% accuracy
Zero and span adjustability
Full 5:1 range turndown
FM & CSA Explosion-proof and
intrinsically safe
4-20 mA output at 12-40 VDC
Water tight cable or conduit
connection optional
1/2” NPT Female process con-
nection or flush mount version
Straight in-line construction for
a slim profile
24 inch (61 cm) cable standard
MODEL 851 SERIES PRESSURE
TRANSMITTERS
through numerous quality checks
which verify secure assembly methods
all the way through the production
process. Nothing less than a 100%
quality level is accepted. With this
PMT quality commitment and our
zero-defect philosophy, the AMETEK
warranty is backed with confidence.
The heart of the Model 851 pressure
transmitter is a silicon piezoresistive
sensing chip. This miniature micro-
etched semiconductor gives a
voltage output proportional to the
applied pressure. This chip is
isolated from the process media
by a stainless steel diaphragm.
A silicone oil or other specified fill
fluid is used to transmit the process
pressure to the sensor.
A surface mount amplifier board,
enclosed in a sealed chamber, is
used to convert the millivolt signal
The Model 851 is the most durable,
accurate and cost-effective pressure
transmitter presently available. It
is designed for years of stable
performance in even the toughest
environmental and media conditions,
such as refineries, petrochemical
facilities, paper & pulp plants, and
waste water treatment facilities.
Approvals include FM and CSA for
both intrinsic safety and explosion-
proof ratings. The Model 851 also
DESCRIPTION
meets NACE standards for offshore
applications, and a one year
warranty is standard with every unit.
The small size and light weight of
the Model 851 transmitter eliminate
the need for complicated mounting
hardware and mechanical supports,
thereby reducing installation time
substantially. The in-line connection
permits simple field wiring without
the need for additional hardware,
adding to the speed and ease of
installation. Its slim profile allows for
mounting in places too tight for most
other transmitters.
A 4-20 mA output is standard with
a 12-40 VDC power supply. The
Model 851 is bench adjustable,
allowing for calibration of zero and
span. With the cover sealed double
O-ring assembly, this transmitter is
weather proof and capable of direct
spray, clean-in-place applications.
OPERATION
Model 851 Series Pressure Transmitters
from the sensor to a calibrated 4-20
mA transmitter output. Transmitter
electronics are surge protected.
Each transmitter is tested over
both pressure and temperature
ranges, and a thick film compen-
sator circuit is used to bring
the output of the sensor into
specification. After compensation,
every transmitter is tested a
second time for pressure and
temperature effects to ensure
that it meets performance
specifications.
DIMENSIONS
IN
(MM) 2 CONDUCTOR CABLE
(PLUS GROUND)
24" STANDARD
2 CONDUCTOR CABLE
(PLUS GROUND)
24" STANDARD
2 CONDUCTOR CABLE
(PLUS GROUND)
24" STANDARD
1.25
(31.8)
6.45
(163.8)
1.25
(31.8)
7.36
(186.9)
DIA.
DIA.
1/2" - 14 NPT
CONDUIT CONNECTION
(OPTIONAL)
1.25
(31.8)
6.29
(159.8)
DIA.
1/2" - 14 NPT
CONDUIT CONNECTION
(OPTIONAL)
1/2" - 14 NPT 1/2" - 14 NPT
MODEL 851
TRANSMITTER
MODEL 851
TRANSMITTER
MODEL 851
FLUSH MOUNT
TRANSMITTER
SPECIFICATIONS
FUNCTIONAL SPECIFICATIONS
SERVICE: Liquid, gas or vapor.
RANGE LIMITS:
0/3 to 0/6 psi (0/.2 to 0/.4 bar)
0/6 to 0/15 psi (0/.4 to 0/1 bar)
0/3 to 0/15 psi (0/.2 to 0/1 bar)
0/6 to 0/30 psi (0/.4 to 0/2.1 bar)
0/20 to 0/100 psi (0/1.4 to 0/6.9 bar)
0/60 to 0/300 psi (0/4 to 0/20.7 bar)
0/200 to 0/1000 psi (0/14 to 0/69.0 bar)
0/600 to 0/3000 psi (0/40 to 0/206.9 bar)
0/1000 to 0/5000 psi (0/70 to 0/344.8 bar)
OUTPUT: 4-20 mADC, limited to 30 mADC.
POWER SUPPLY: 12 to 40 VDC with
reverse polarity protection.
LOOP RESISTANCE: 1400 ohms max at 40
volts.
TURNDOWN: 5:1.
ZERO ADJUST: +10%.
SPAN ADJUST: +10%.
TEMPERATURE LIMITS:
Electronics (Ambient): -40o F to 140o F
(-40o C to 60o C)
Process Interface: -40o F to 212o F (-40o C
to 100o C)
Storage: -40o F to 212o F (-40o C to 100o C)
OVERRANGE: 300% upper range limit.
HUMIDITY LIMITS: 0-100% RH.
PERFORMANCE SPECIFICATIONS
ACCURACY: +0.25% of calibrated span
including linearity, hysteresis and
repeatability. (BFSL)
RESPONSE TIME: Time constant of 20
milliseconds.
STABILITY: +0.5% of upper range limit for
six months.
TEMPERATURE EFFECT:
(includes zero and span)
Compensated: -20o F to 180o F (-29o C
to 82o C)
Between 30o F and 130o F (-1o C and
54o C): +1% of URL per 50o F (28o C)
Between -20o F and 180o F (-29o C and
82o C): +1.6% of URL per 50o F (28o C)
POWER SUPPLY EFFECT: +0.005% Full
Scale per volt.
SURGE PROTECTION: Standard.
VIBRATION EFFECT: +0.1% of upper
range limit for 3 g to 200 Hz.
POSITION EFFECT: Zero shifts up to
0.01 psi.
OVERRANGE EFFECTS: +0.15% Full
Scale per 200% of maximum range.
PHYSICAL SPECIFICATIONS
MATERIALS OF CONSTRUCTION:
Process Wetted Parts: 316 Stainless
Steel
Diaphragm (Models 851F): Hastelloy “C”
Non Wetted Parts: 316 Stainless Steel;
VITON “O” Ring
Fill Fluid: DC 200 Silicone (Standard)
Process Connection: Reference Model
Code
Electrical Connection: Reference Model
Code
Weight: 1 lb. (450 grams)
Cable Length: 24 inches (61 cm), 22 AWG
CLASSIFICATIONS
FACTORY MUTUAL:
Intrinsically safe for Class I, II, III Division
I, Groups A, B, C, D, E, F, G for
hazardous locations per AMETEK Dwg.
BK750407.
Entity Requirement: Imax = 225mA, Vmax
= 36V, Ci = 0.126 µf., Li = 0 mH
Explosion Proof for Class I, II, III Division
1, Groups C, D,E, G, for hazardous
locations. NEMA 4 Enclosure. Conduit
seal must be within 18” of transmitter.
CANADIAN STANDARDS ASSOCIATION:
Exia-Intrinsically safe for Class I, Division
1 & 2, Groups A, B, C, D; Class II,
Groups E, F, G when connected per
AMETEK Dwg. BK750483.
Explosion Proof for Class I, Division 1,
Groups B, C, D; Class II, Groups E, F, G;
Class III for Hazardous locations.
Enclosure 4, Temperature Code T3C
(160o C)
CALIBRATION
MODCAL II CALIBRATION SYSTEM*
NEGATIVE
TURNDOWN
(COURSE)
ADJUSTMENT
SPAN
ADJUSTMENT
GROUND
POSITIVE
ZERO (FINE)
ADJUSTMENT
*Contact factory for information on calibration system.
© 1999, by AMETEK, Inc. All rights reserved.
2.5M699 (110048)
U.S. GAUGE PMT PRODUCTS
820 PENNSYLVANIA BLVD., FEASTERVILLE, PENNSYLVANIA 19053 U.S.A.
TEL: (215) 355-6900 FAX: (215) 355-2937 www.ametekusg.com
Model 851 Series Pressure Transmitters
ORDERING INFORMATION
MODEL NUMBER
851-T-G-0015-C-L-S-A-S-(0-15 PSI)
MODEL 851 ELECTRONIC PRESSURE TRANSMITTER
PROCESS CONNECTION
T = 1/2” NPT
F = FLUSH1
PRESSURE TYPE
G = GAUGE
PRESSURE RANGE
3015 = 3-15 PSI (.2 to 1 bar)
0006 = 0/3 To 0/6 PSI (0/0.2 to 0/0.4 bar)
0015 = 0/6 To 0/15 PSI (0/0.4 to 0/1 bar)
0030 = 0/6 To 0/30 PSI (0/0.4 to 0/2.1 bar)
0100 = 0/20 To 0/100 PSI (0/1.4 to 0/6.9 bar)
0300 = 0/60 To 0/300 PSI (0/4 to 0/20.7 bar)
1000 = 0/200 To 0/1000 PSI (0/14 to 069.0 bar)
3000 = 0/600 To 0/3000 PSI (0/40 to 206.9 bar)
5000 = 0/1000 To 0/5000 PSI (0/70 to 0/344.8 bar)
ELECTRICAL CONNECTION
N = STANDARD NUT/CABLE3*
C = 1/2" NPT FEMALE CONDUIT CONNECTION/CABLE*
DIAPHRAGM
L = 316L STAINLESS STEEL
H = HASTELLOY
FILL
S = SILICONE
AGENCY APPROVAL
A = FACTORY MUTUAL (FM) AND CANADIAN STANDARD
ASSOC. (CSA) IS & EXP. PROOF2
C = FACTORY MUTUAL (FM) AND CANADIAN STANDARD
ASSOC. (CSA) IS1
COUPLING (FLUSH ONLY)
S = 316 SS COUPLING; TEFLON GASKET
P = 316 SS PLUG, COUPLING; TEFLON GASKET
N = NO COUPLING; TEFLON GASKET
CALIBRATED RANGE
SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE
1. Flush Connection only available up to 300 PSI (20 bar).
2. Explosion Proof Approval requires “C” electrical connection option.
3. Not available with agency approval “A”, FM/CSA explosion-proof.
*Cable length is 24” (22 AWG) standard.
TYPICAL WIRING
DIAGRAM
NEGATIVE
TURNDOWN
(COURSE)
ADJUSTMENT
SPAN
ADJUSTMENT
GROUND
POSITIVE
ZERO (FINE)
ADJUSTMENT
1/2" NPT CONDUIT
SHIELD/DRAIN
(BLACK) (RED)
(GREEN)
RECEIVER/CONTROLLER POWER SUPPLY
Example:
851-T-G-0015-C-L-S-A-S (0-15 PSI)
1/2" NPT Connection, Pressure Type Gauge, 0/6 To 0/15 PSI
(0/0.4 to 0/1 bar), Female Conduit Connection/Cable, 316L
Stainless Steel, Silicone Fill, Factory Mutual (FM) and Canadian
Standard Assoc. (CSA) IS & Exp. Proof, 316 Stainless Steel
Coupling and Teflon Gasket, 0-15 PSI Calibrated Range