165855 Cylinder Pressure Transducer
Datasheet

Bently Nevada Machinery Condition Monitoring

166815 Rev. LDescription
The Cylinder Pressure System consists of the 165855 Cylinder
Pressure Transducer and the 146824 Interconnect cable. It is
intended for measuring the cyclic absolute pressure changes
inside a reciprocating compressor cylinder. This transducer isan integral part of a Reciprocating Compressor Condition
Monitoring and Asset Management System when utilized withour 3500/77M Cylinder Pressure Monitor and System 1 Plant
Asset Management Software.
The Cylinder Pressure Transducer has a robust design forhigh reliability in harsh chemical environments. The unique,patent-pending design also allows the transducer tocontinue to provide an accurate pressure reading, even after
being continually cycled over large pressure gradients for anextended period of time. The transducer can also withstandover-pressure situations caused by application upsets
without diaphragm degradation, returning to normal
operation when the operating pressure returns to thetransducer’s specified operating pressure range. The
Cylinder Pressure Transducer is also designed to meet NEMA
4X and IP67 conditions for moisture ingression.
The wetted surface of the transducer is typically installed into
an isolation valve or similar pressure indicator port on thecompressor. A special adapter is usually required to provide
a seal between the pressure indicator port and thetransducer (such as the 166393 adapter). The electronics
portion of the Cylinder Pressure Transducer is separated fromthe wetted surface by 1 metre of cable. The electronics must
be secured on or near the compressor for optimalperformance.

165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. L

Each pressure sensor will be shipped withpressure-temperature compensation data inorder to optimize the measurement. Inputting
the supplied data points into the 3500/77
Cylinder Pressure Monitor can minimize theoperating temperature effects on thetransducer.

-40 to 185 (electronics housing) °F-40 to 302 (sensor head) °F
Overvoltage
Category

Specifications
Cylinder Pressure Transducer
SystemOperation outside the specified limits will resultin false or inaccurate readings.
Transducer Characteristics
0 to 100/ 250/ 500/ 1000/ 2500/Measurement 5000/ 10,000 psia
Range
0 to 6.8/ 17/ 34.5/ 69/172/ 345/ 689
barProof (Over)
Pressure1.5X Full Scale

Burst Pressure

3X Full Scale (2X FS on 689 bar/10,000 psia units)

Full Scale
Output10 ± 0.3 Vdc

Zero

0.5 ± 0.1 Vdc

Power Supply

18 to 30 Vdc

Max. Current< 15 mA

Compensated -40 to 85° C
Temperature -40 to 185° F-1.0 to +2.0 (for 6.8 and 17 bar/ 100and 250 psia) %FS
Thermal Zero
Shift

-0.5 to +1.5 (for all other pressureranges)
Note: Within compensatedtemperature range.

ThermalSensitivity
Shift

See Graphs and Figures on page 6.

Linearity,
Hysteresis,
Repeatability£ ±0.3 %FSFrequency
response

0Hz to 5500 Hz ± 1 dB

OperatingTemperature-40 to 85 (electronics housing) °C-40 to 150 (sensor head) °C

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Datasheet

166815 Rev. L

Accessories

Physical & Environmental
Weight

250 g (0.55 lbm)
Sensor Head 150 g (0.33 lbm)

Dimensions

See diagram

Materials

Gold plated, per MIL-G-45204 Type III
Grade A, C-276 welded to a 316L
stainless steel body. (patentpending)

Humidity

95% condensing on exposed
surfaces excluding connector

Body

Designed to meet IP67

-40°C to 150 °C (-40 °F to 302 °F)

PollutionDegree

2The o-ring utilized must be compatible
with the type of gas or fluid that thetransducer will be operated in. Consult
your local representative for additional
assistance.

68 N-m (50 lbf-ft)

04500022

ADH Dow 4 Elec Ins Comp 4cc Tub

3500/77M

Cylinder Pressure Monitor

5. If the equipment is used in a manner not
specified by the manufacturer, theprotection provided by the equipment
may be impaired.
It is highly recommended that an isolation
valve be used in conjunction with the 165855
Cylinder Pressure Transducer. Valve materials
must be compatible with sour gas
environments.

Hydrogen sulfide, sulfuric acid,butane, fuel oil, petroleum oil, turbine
Hifluor (black)oil, propane, propylene, butylenes,and natural gas.

Mounting
Torque½-14 NPT Adapter

4. Depending upon application, acousticresonance may occur. For specificdetails on acoustic resonance andindicator valves, contact your local sales
or service representative for more
information.

O-rings

Ammonium hydroxide, anhydrous
ammonia

166393-02

3. O-ring must be adequately lubricatedwith supplied Parker Super-O-Lube prior
to installation.

Maximum Use
2000 meters above sea level
Altitude

Ethylene
Propylene(purple)¾-14 NPT Adapter

2. Transducer diaphragm may become
damaged upon contact with any foreign
object. Care must be taken to protect
diaphragm during handling andinstallation to help ensure proper
performance.

Ethylene Propylene:

Fluid media compatible with C-276
and either Hifluor or Ethylene
Propylene o-ring material (commonmedia below)

166393-01

1. 165855 designed to mate per SAE J1926.
Transducer will not seal pressure
sufficiently if not mated per SAE J1926.

Hifluor: -26 °C to 150 °C (-15 °F to 302°F)

PressureMedia

Mounting clamp for electronics
housingNotes

Dependent upon O-ring material
OperatingTemperature

29660-01

For more information about installing andmaintaining this product, refer to the Cylinder
Pressure Transducer User Guide (document
166820).

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165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. L

Compliance andCertifications
FCC
This device complies with part 15 of theFCC Rules. Operation is subject to thefollowing two conditions:llThis device may not cause harmfulinterference.
This device must accept any
interference received, includinginterference that may cause
undesired operation.

EMC
EN 61326-1
EMC Directive 2014/30/EURoHS
RoHS Directive 2011/65/EU

ATEX (where the applicable dash option has
been ordered)
EN 60079-0
EN 60079-11
EN 60079-15
ATEX Directive 2014/34/EU

Hazardous Area Approvals
For the detailed listing of country and productspecific approvals, refer to the Approvals Quick
Reference Guide (108M1756) available from
Bently.com.

ATEX/IECEx
165855

II 1 G Ex ia IIC T4 Ga
II 3 G Ex nA IIC T4 Gc
T4 @ Ta = -40°C to +85°C4/9

165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. L

146824 Cylinder Pressure
Transducer Cable

Ordering Information
For the detailed listing of country and productspecific approvals, refer to the Approvals Quick
Reference Guide (108M1756) available from
Bently.com.

146824-AAAA
A: Length Option

165855 Cylinder Pressure
Transducer
All transducers have 7/8-14 UNF thread
and are supplied with North Americanand ATEX approvals.

165855-AA
A: Pressure Range Option
01

0 to 6.8 bar (0 to 100 psia)

02

0 to 17 bar (0 to 250 psia)

03

0 to 34.5 bar (0 to 500 psia)

04

0 to 69 bar (0 to 1,000 psia)

05

0 to 172 bar (0 to 2,500 psia)

06

0 to 345 bar (0 to 5,000 psia)

07

0 to 689 bar (0 to 10,000 psia)

11

0 to 6.8 bar (0 to 100 psia) w/ armor

12

0 to 17 bar (0 to 250 psia) w/ armor

13

0 to 34.5 bar (0 to 500 psia) w/ armor

14

0 to 69 bar (0 to 1,000 psia) w/ armor

15

0 to 172 bar (0 to 2,500 psia) w/ armor

16

0 to 345 bar (0 to 5,000 psia) w/ armor

17

0 to 689 bar (0 to 10,000 psia) w/ armor

5/9001010 ft (3 m)0025

25 ft (7.6 m)

0050

50 ft (15.2 m)

0100

100 ft (30.5 m)

0200

200 ft (61.0 m)

0300

300 ft (91.4 m)

0400

400 ft (121.9 m)

0500

500 ft (152.4 m)

1000

1,000 ft (304.8 m)

165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. L

Graphs and Figures

Figure 1: Typical Thermal Sensitivity Shift

Figure 2: 165855-AA Cylinder Pressure Transducer and Bore per SAE J1926

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165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. L

Figure 3: 146824-AAAA Cylinder Pressure CableAdapter notes:
1. The 166393-AA adapter is rated to 345 bar (5,000 psi) per
ASME B31.1.
2. When exceeding 345 bar (5,000 psi), the 166393-AA is notrecommended. In applications exceeding 345 bar (5,000psi), direct mounting of the 165855 transducer per SAE
J1926 is highly recommended.
Figure 4: 166393-AA Adapter

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Datasheet

166815 Rev. L

Figure 5: 29660-01 Mounting Clamp, use with M6 or ¼-20 (not supplied)

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165855 Cylinder Pressure Transducer
Datasheet

166815 Rev. LCopyright 2020 Baker Hughes Company. All rights reserved.

Bently Nevada, Orbit Logo and System 1 are registered trademarks of Bently Nevada, a Baker Hughes Business, in theUnited States and other countries. The Baker Hughes logo is a trademark of Baker Hughes Company. All otherproduct and company names are trademarks of their respective holders. Use of the trademarks does not imply any
affiliation with or endorsement by the respective holders.
Baker Hughes provides this information on an “as is” basis for general information purposes. Baker Hughes does notmake any representation as to the accuracy or completeness of the information and makes no warranties of any
kind, specific, implied or oral, to the fullest extent permissible by law, including those of merchantability and fitness
for a particular purpose or use. Baker Hughes hereby disclaims any and all liability for any direct, indirect,
consequential or special damages, claims for lost profits, or third party claims arising from the use of theinformation, whether a claim is asserted in contract, tort, or otherwise. Baker Hughes reserves the right to makechanges in specifications and features shown herein, or discontinue the product described at any time without
notice or obligation. Contact your Baker Hughes representative for the most current information.
The information contained in this document is the property of Baker Hughes and its affiliates; and is subject tochange without prior notice. It is being supplied as a service to our customers and may not be altered or its content
repackaged without the express written consent of Baker Hughes. This product or associated products may becovered by one or more patents. See Bently.com/legal.

1631 Bently Parkway South, Minden, Nevada USA 89423
Phone: 1.775.782.3611 or 1.800.227.5514 (US only)
Bently.com

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