GE Baker Hughes 8000 Series User manual

bhge.com
BHGE Data Classification: Public
8000/8100/8200
Series
Trench Etched Resonant Pressure Sensor
Instruction Manual

© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | i
Safety
The manufacturer has designed this sensor to be safe when operated using the procedures
detailed in this manual. Do not use this sensor for any other purpose than that stated.
This publication contains operating and safety instructions that must be followed for safe
operation and to maintain the sensor in a safe condition. The safety instructions are either
warnings or cautions issued to protect the user and the equipment from injury or damage.
Use qualified*personnel and good engineering practice for all procedures in this publication.
Toxic Materials
There are no known toxic materials used in this sensor.
Maintenance
The sensor must be maintained using the manufacturer’s procedures and these should be
carried out by authorized service agents or the manufacturer’s service departments.
bhge.com
For technical advice contact the manufacturer.
WARNING Do not apply pressure greater the maximum safe working
pressure to the sensor.
* A qualified technician must have the necessary technical knowledge, documentation, special test
equipment and tools to carry out the required work on this equipment.

ii | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.
Symbols
Abbreviations
The following abbreviations are used in this manual.
Note: Abbreviations are the same in the singular and plural.
Symbol Description
This equipment meets the requirements of all relevant European safety
directives. The equipment carries the CE mark.
This symbol, in this manual, indicates a hazardous operation.
This symbol indicates do not throw-away in domestic bin, hazardous
material, dispose correctly in accordance with local regulations.
Abbreviation Description
a Absolute
ASCII American Standard Code for Information Interchange
°C Degrees Celsius
atm Atmosphere
bps Bits per second
cmHg Centimetre of mercury
CR Carriage return
DC Direct current
EEPROM Electrically Erasable Programmable Read Only Memory
FS Full-scale
ftH2O Feet of water
hPa Hecto Pascal
inH2O Inches of water
inHg Inch of mercury
kg Kilogram
kg/cm2Kilogram per centimetre squared
kg/m2Kilogram per metre squared
kPa Kilo Pascal

© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | iii
lb/ft2Pounds per foot squared
LF Line feed
mA Milli Ampere
mbar Millibar
mbar a Millibar absolute
mH2O Metres of water
mHg Metre of mercury
mm Millimetre
mmH2O Millimetres of water
mmHg Millimetre of mercury
MPa Megapascal
MΩMega ohm
n/a Not applicable
Pa Pascal
PIN Personal identification number
ppm Parts per million
psi Pound per square inch
RS-232 ANSI TIA-232 communication standard
RS-485 ANSI TIA-485 communication standard
TERPS Trench etched resonant pressure sensor
USB Universal serial bus
V Volt
Abbreviation Description

iv | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.

© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | v
Contents
1. Installation 1
1.1 Introduction 1
1.2 Connecting TERPS to a Pressure Source 1
1.3 Media Compatibility 2
1.4 Pressure Containment 2
1.5 Power Requirements 3
1.6 Software 3
1.6.1 USB Driver 3
1.6.2 LabVIEW Driver 3
1.6.3 Mobile Application 3
2. RPS Pressure Measurement 5
2.1 Measuring the Frequency 5
2.2 Measuring the Diode Voltage 5
2.3 Calculating Pressure 5
2.4 Stored Coefficients 6
3. DPS Pressure Measurement 9
3.1 Serial Data Communications Settings 9
3.2 Applications 9
3.3 RS-485 Connections 9
3.4 RS-232 Connections 10
3.5 USB Connection 10
3.6 Measuring Pressure 11
3.7 Factory Defaults 11
4. Programming Guide 13
4.1 Command Summary 13
4.2 Communication Modes 14
4.2.1 Direct Mode 14
4.2.2 Addressed Mode 14
4.3 Command Syntax 15
4.3.1 Direct Mode Syntax 15
4.3.2 Addressed Mode Syntax 15
4.4 Measurement Commands 15
4.4.1 R - Get Reading 15
4.4.2 G - Get New Reading and Transmit 16
4.4.3 Z - Read Raw Data 16
4.5 Information Commands 17

vi | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.
4.5.1 I - Transducer Identity 17
4.6 General Set-up Commands 18
4.6.1 A - Auto-send Reading 18
4.6.2 N - Set Device (Transducer) Address 19
4.6.3 Q - Set Measurement Speed 19
4.6.4 U - Set Units 20
4.7 PIN Protected Set-up Commands 21
4.7.1 C - User Calibration 21
4.7.2 H - Change Slope 23
4.7.3 M - User Message 24
4.7.4 O - Communication Settings 24
4.7.5 P - Change PIN 26
4.7.6 S - Set Offset 27
4.8 Factory Commands - Query Only 28
4.8.1 E - Crystal Reference Frequency 28
4.8.2 L - Load Calibration Coefficients 28
4.8.3 T - Analogue/Digital Converter Set-up 29
4.8.4 V - Transducer Type and Settings 29
4.8.5 W - EEPROM Query 30
4.9 Error Messages 30
4.9.1 Incorrect User Command 30
4.9.2 Transducer Fault 31
Appendix A. Fault Finding 33
Appendix B. RPS EEPROM Format 35

Introduction
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 1
1. Installation
1.1 Introduction
The 8XXX Series uses TERPS (trench etched resonant sensor) technology. The RPS 8XXX
produces a frequency and diode voltage output. The DPS 8XXX includes a microprocessor to
produce a serial digital output.
Figure 1-1: TERPS Sensor Chip
The 80XX, 82XX and 83XX are harsh media isolated product. Isolation is achieved by
hermetically sealing the sensor chip in an oil filled chamber. The weight of this oil gives a
g-sensitivity as a pressure offset error.
The 81XX is not a harsh media isolated product. The pressure media comes directly into
contact with the sensor chip. Care must be taken to ensure the pressure media does not
damage the sensor chip. There is negligible change in offset due to mounting position and
vibration.
To calibrate the 8XXX Series, the unit is mounted vertically with the pressure port at the
lowest point. Orientation other than this produces a pressure offset error as specified in the
data sheet. The error is most noticeable at lower pressure ranges.
Note: The g-sensitivity will also create an error in a high vibration environment and the
unit should be mounted accordingly.
1.2 Connecting TERPS to a Pressure Source
When mounting the sensor, seal the mating surfaces. Failure to properly seal may affect
performance or calibration accuracy.

Chapter 1. Installation
2 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.
Male threaded pressure connectors must not be sealed or constrained against the face at the
base of the thread. The forward cone or flat face should always be used as indicated below.
Depth versions should not be used at hyperbaric pressures above 70 bar (approximately 700
m of water).
1.3 Media Compatibility
The media compatibility of the TERPS sensors is shown in Table 1-1.
Note: Fluid classification complies with Regulation (EC) No 1272/2008. Statements
comply with Pressure Equipment Directive 2014/68/EU.
1.4 Pressure Containment
The pressure containment of the TERPS sensors is shown in Table 1-2.
Table 1-1: Media Compatibility
Product Pressure Range Media Compatibility
81XX 0 to 3.5 bar Non-condensing dry gases compatible with silicon,
silicon dioxide, RTV adhesive, stainless steel 316L
and glass.
80XX 0 to 70 bar Fluids compatible with Stainless Steel 316L and
Hastelloy C276.
82XX
83XX
0 to 70 bar Fluids compatible with Hastelloy C276.
Table 1-2: Pressure Containment
Product Pressure Range Pressure Containment
DPS 81XX 0 to 3.5 bar 7 bar maximum
DPS 80XX 0 to 7 bar 70 bar maximum
>7 to 70 bar 200 bar maximum
98

Power Requirements
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 3
1.5 Power Requirements
The TERPS sensor should be connected to a stable power supply. The power supply
requirements are shown in Table 1-3.
1.6 Software
1.6.1 USB Driver
Drivers for the USB sensor are available from FTDI and should auto-install in any Windows®
or Android™ operating system.
1.6.2 LabVIEW Driver
A National Instruments certified LabVIEW driver is available to download from the National
Instruments’ website.
http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=30206
The driver includes a Virtual Instrument to discover a sensor’s address. Example code
snippets are supplied with the driver.
The LabVIEW driver is plug-and-play compatible with the USB sensor. A USB to RS-485
adapter, or a USB to RS-232 adapter, can be used to communicate with the RS-485 and
RS-232 sensors.
1.6.3 Mobile Application
A TERPS mobile application for Android™ is available for free download from Google Play™.
The TERPS application displays pressure from any USB TERPS sensor.
Barometric TERPS sensors can optionally display the following aeronautical parameters: QFE,
QNH, QFF and MSL.
Table 1-3: Power Supply Requirements
Product Supply Voltage (V DC) Supply Current
RPS Versions 6 to 28 3.5 mA nominal
20 mA peak
RS-485 and RS-232
Versions 11 to 28 16 mA nominal 32 mA peak
USB Version Supplied by USB host 40 mA nominal
100 mA peak

Chapter 1. Installation
4 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.

Measuring the Frequency
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 5
2. RPS Pressure Measurement
The RPS version of the TERPS sensor requires the user to measure a frequency and a voltage
to calculate pressure. The TERPS sensor has a very high level of repeatability that needs to be
matched by the measurement system.
Note: Best practice, when measuring a TERPS device, take both the frequency and
voltage measurements together. Where this is not possible, the measurements should be
taken as closely together as possible. Control the environment in which the TERPS is
situated so it is not subjected to sudden changes in temperature and pressure.
2.1 Measuring the Frequency
The frequency of the TERPS sensor chip is output as a TTL square wave referenced to ground
in the range of 25 to 40 kHz. The frequency of the square wave needs to be measured to a
better than 6.5 digits (i.e. 30 kHz to better than 0.05 Hz) to allow the sensor to meet quoted
specification.
To make sure the calculated output is correct, the measurement device should be regularly
calibrated refer to the manufacturer’s instructions against a traceable standard.
2.2 Measuring the Diode Voltage
The diode signal is referenced to ground. It is a nominal 0.5 V at room temperature, and
changes with a nominal -2 mV/°C. To achieve the quoted specification of the sensor this
signal must be measured to better than 0.01 mV.
To make sure the calculated output is correct, the measurement device should be regularly
calibrated refer to the manufacturer’s instructions against a traceable standard.
2.3 Calculating Pressure
During manufacture, a large number of pressures and temperatures are applied to the sensor
to build-up a mathematical description of its behavior. This data is then used to generate a
polynomial equation that relates the measured outputs from the sensor (bridge output and
temperature output) to the applied pressure.
The following example assumes a 5th order pressure (P5) and a 4th order temperature signal
(T4). If other orders of fit are used, these equations will need to be expanded to suit.

Chapter 2. RPS Pressure Measurement
6 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.
This equation is in the form:
The coefficients Ki, j, Xand Y are printed on the calibration certificate supplied with the
pressure sensor. A sample set is shown in Table 2-1:
2.4 Stored Coefficients
The coefficients are also stored internally on a serial EEPROM. See Appendix B. for details on
data format and communication information.
where: P= Applied pressure in mbar
Ki, j = Calibration coefficient
x= Pressure signal in Hz
X= Pressure normalizing factor
y= Temperature signal in mV
Y= Temperature normalizing factor
Table 2-1: Sample Coefficients
Sample Coefficients Sample Coefficients
Coefficient Value Coefficient Value
K00 9.173625E+02 K31 2.975355E-14
K01 -8.654275E-02 K32 -1.591914E-16
K02 3.705644E-05 K33 -3.095734E-18
K03 -3.071498E-08 K34 0.000000E+00
K04 0.000000E+00 K40 4.689744E-15
K10 3.792730E-01 K41 -1.867269E-18
K11 4.884866E-06 K42 -2.591512E-20
K12 -8.219704E-09 K43 6.066456E-23
K13 -3.283229E-11 K44 0.000000E+00
K14 0.000000E+00 K50 -2.043712E-20
K20 9.252440E-06 K51 -4.652603E-21
K21 4.893925E-11 K52 2.124089E-23
K22 2.872573E-14 K53 3.812421E-25
K23 -1.617304E-15 K54 0.000000E+00
K24 0.000000E+00 X 2.425645E+04
K30 1.185548E-10 Y 5.577031E+02
PK
ij
xX–
iyY– j
j0=
4

i0=
5

=

Stored Coefficients
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 7
The internal EEPROM is only available on some electrical connector variants of the RPS 8XXX
series, see data sheet or calibration certificate for electrical connection details.

Chapter 2. RPS Pressure Measurement
8 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.

Serial Data Communications Settings
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 9
3. DPS Pressure Measurement
The pressure reading and pressure units are outputted as ASCII text. The reading rate is user
programmable from ten readings per second to one reading per 9999 seconds.
3.1 Serial Data Communications Settings
Bi-directional digital communication, no handshaking, 9600 baud, 8 bit data, 1 stop bit. The
sensor may be used as a single transducer directly connected to a serial interface. It can also
be part of a network of devices using the programmed addressing facility.
3.2 Applications
The sensor may be used as a single transducer directly connected to a serial interface. It can
also be part of a network of devices using the programmed addressing facility.
3.3 RS-485 Connections
Standalone RS-485 electrical connections:
i. RS-485 B (or RS-485 -)
ii. +ve supply
iii. 0V supply
iv. RS-485 A (or RS-485 +)
v. Transducer body (screen)
Note: For electrical connections refer to the sales data sheet.
Other connectors available, refer to manufacturer.
Figure 3-1: RS-485 Direct Connection
Pressure
11 - 28 V DC
0 V
RS-485 A
RS-485 B

Chapter 3. DPS Pressure Measurement
10 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.
Figure 3-2: RS-485 Network Connection
3.4 RS-232 Connections
Standalone RS-232 electrical connections:
i. RS-232 Tx
ii. +ve supply
iii. 0V supply
iv. RS-232 Rx
Note: For electrical connections refer to the sales data sheet.
Figure 3-3: RS-232 Direct Connection
3.5 USB Connection
Standalone USB electrical connection:
Figure 3-4: USB Connection
Pressure
Device 1
Address 1
Pressure
Device 2
Address 2
Pressure
Device 3
Address 3
+0V +0V +0V
RS-485
Terminator
RS-485
Terminator
RS-485
Interface
RS-485 +
RS-485 –
Pressure
11 - 28 V DC
0 V
RS-232 Tx
RS-232 Rx
Pressure
Micro-USB socket

Measuring Pressure
© 2010 Baker Hughes, a GE company – All rights reserved. 8000/8100/8200 Series Instruction Manual-English | 11
The maximum USB cable length is 9 ft 10 in (3 metres). The transducer can be connected to a
PC, or to a mobile device.
Drivers are available for the following operating systems:
• Android™
• Linux®
• Microsoft Windows®
3.6 Measuring Pressure
The frequency output from the sensor is counted for a fixed number of cycles by the
microprocessor. Measurement cycles are continuous, each cycle delivers new values of
frequency and temperature. See Section 4.4 on page 15 for instructions on how to read a
pressure measurement from the transducer.
3.7 Factory Defaults
Transducers are shipped with the following factory defaults (unless alternatives have been
requested):
Table 3-1: Factory Defaults
Parameter Value
Units mbar, displayed as text
after reading.
PINa
a. PIN functions are disabled in USB versions. The
default PIN value is not applicable for USB versions.
000 (not set)
Address Direct mode
Long error messages Present
Communications Set-up 9600, 8, N, 1
Update rate 1 reading/second
Filter Disabled
User message None
Measurement speed 300 ms to 560 ms
Mode Direct

Chapter 3. DPS Pressure Measurement
12 | 8000/8100/8200 Series Instruction Manual-English © 2010 Baker Hughes, a GE company – All rights reserved.