Advanced Instruments GPR-2500 User manual

2855 Metropolitan Place, Pomona, CA 91767 USA ♦Tel: [phone], Fax: [phone], www.aii1.com, e-mail: [email protected] Rev 10/15
ISO 9001:2008 Certified
INTERTEK Certificate No. 485
Technical Specifications *
Accuracy: < 2% of FS range under constant conditions
Analysis: 0-1%, 0-5%, 0-10%, 0-25% FS ranges; auto-ranging
or fixed single range
Application: Oxygen analysis in inert, hydrocarbon, helium, hydro-
gen, mixed and acid (CO2) gas streams
Approvals: Certified for use in hazardous areas - see lower right
UL: United States: UL 1203, UL 913, UL 508
Canada: CAN/CSA C22.2 No. 30-M1986,
CAN/CSA C22.2 No. 157-92,
CAN/CSA C22.2 No. 14-10
ATEX: Directive 94/9/EC
Area Classification: Certified for use in hazardous areas - see lower right
Alarms: Two user configurable alarms: magnetic coil relays
rated 3A at 100 VAC, programmable alarm delays,
alarm bypass for calibration and system fail alarm
Calibration: Max interval—3 months. Air calibrate with clean source
of certified span gas, compressed, or ambient (20.9%
O2) air on 0-25% range.
Compensation: Barometric pressure and temperature (ATEX)
Temperature (UL)
Connections: 1/4" compression tube fittings
Controls: Water resistant keypad; menu driven range selection,
calibration and system functions
Display: Graphical LCD 2.75” x 1.375”; resolution 0.001%;
displays real time ambient temperature and pressure
Enclosure: NEMA 3R for rain in outdoor applications (UL)
NEMA 4X (ATEX)
Flow: Not flow sensitive; recommended flow rate 1-2 SCFH
Linearity: ±1% of full scale
Pressure: Inlet - regulate to 5-30 psig to deliver 1-2 SCFH flow;
vent - atmospheric
Power: 12-28 VDC (UL and ATEX Certified)
110-220 VAC (ATEX Certified)
Response Time: 90% of final reading in < 2 minutes
Sample System: Unique liquid drain manifold and sensor, flow indicator
Sensitivity: < 0.5% of FS range
Sensor Model: GPR-11-32-LD; XLT-11-24-LD for gases containing
>0.5% CO2
Sensor Life: 24 months in air at 25ºC and 1 atm
Signal Output: 4-20mA non-isolated or 1-5V; optional Modbus RTU
communication
Operating Range: -10ºC to 45ºC (GPR sensor); -10ºC to 45ºC (XLT)
Warranty: 12 months analyzer; 12 months sensor
Wetted Parts: Stainless steel
Optional Equipment
Automated sample conditioning system (see other side)
GPR-11-32-LD sensor for non-acid (CO2) gas streams; 32 month life
* Specifications subject to change without notice
Exia
UL Certified
File E343386
Class I, Division 1, Groups C and D
T4 Tamb -20⁰C to +50⁰C
GPR-2500 AIS-LD
Oxygen Analyzer
Unique Liquid Drain Sensor Manifold
Full Featured Oxygen Analyzer
Optional Modbus RTU Communication
Drains Free Liquids
0080
ATEX Certified - Directive 94/9/EC
Examination Cert: INERIS 08ATEX0036
II 2 G
Ex d [ib] ib IIB T4 Gb
Tamb -20⁰C to +50⁰C
UL or ATEX Certified for Hazardous Areas

Advanced Instruments Inc.
2855 Metropolitan Place, Pomona, California 91767 USA ♦Tel: [phone], Fax: [phone] ♦ www.aii1.com ♦ e-mail: [email protected]
GPR-2500 AIS LD
% OXYGEN ANALYZER
Owner's Manual
Revised March 2015

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Table of Contents
Introduction 1
Quality Control Certification 2
Safety 3
Features & Specifications 4
Operation 5
Maintenance 6
Spare Parts 7
Troubleshooting 8
Warranty 9
Material Safety Data Sheets 10
Explosion Proofing Electrical Connections Appendix A
The appendices referenced above are an integral part of the documentation, installation and maintenance of this analyzer
to comply with all applicable directives. It is important that users review these documents before proceeding.

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1. Introduction
Your new oxygen analyzer incorporates an advanced electrochemical sensor specific to oxygen along with state-of-the-art
digital electronics designed to give you years of reliable precise oxygen measurements in a variety of industrial oxygen
applications. More importantly, it has been constructed as explosion proof/intrinsically safe in accordance with Safety
Standards: UL 913 Seventh Edition, Referencing UL 60079-0:2005 and UL 60079-11:2009 and CSA C22.2 No. 157-92
Third Edition for use in Class I, Div 1, Groups C and D hazardous locations and the ATEX Directives 94/9/EC for zone 1
Group IIB.
Please refer to Appendix A for making electrical connections that maintains the desired level of protection.
To obtain maximum performance from your new oxygen analyzer, please read and follow the guidelines provided in this
Owner’s Manual.
Every effort has been made to select the most reliable state of the art materials and components, to design the analyzer for
superior performance and minimal cost of ownership. This analyzer was tested thoroughly by the manufacturer prior to
shipment for best performance.
However, modern electronic devices do require service from time to time. The warranty included herein plus a staff of
trained professional technicians to quickly service your transmitter is your assurance that we stand behind every
transmitter sold.
The serial number of this analyzer may be found on the inside the analyzer enclosure. You should note the serial number
in the space provided and retains this Owner’s Manual as a permanent record of your purchase, for future reference and
for warranty considerations.
Serial Number: _______________________
Advanced Instruments Inc. appreciates your business and pledges to make every effort to maintain the highest possible
quality standards with respect to product design, manufacturing and service.
Analytical Industries Inc.
dba Advanced Instruments Inc.
2855 Metropolitan Place, Pomona, CA 91767 USA
GPR-2500 AIS/2500 AIS LD
0080
Serial No.:
Year of Manufacture:
INERIS 08ATEX0036
II 2 G
Ex d [ib] ib IIB T4 Gb
Tamb -20⁰C to +50⁰C
WARNING: POTENTIAL ELECTROSTATIC CHARGING HAZARD – SEE
INSTRUCTIONS

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2. Quality Control Certification
See analyzer packing slip/Instruction Manual that came with the analyzer for QC certificate

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3. General Safety & Installation
This section summarizes the essential precautions applicable to the GPR-2500 AIS LD Oxygen Analyzer. Additional
precautions specific to the individual transmitter is contained in the following sections of this manual. To operate the
transmitter safely and obtain maximum performance follow the basic guidelines outlined in this Owner’s Manual.
Caution: This symbol is used throughout the Owner’s Manual to Caution and alert the user to recommended
safety and/or operating guidelines.
Warning: This symbol is used throughout the Owner’s Manual to Warn and alert the user of the presence of
electrostatic discharge.
Danger: This symbol is used throughout the Owner’s Manual to identify sources of immediate Danger such
as the presence of hazardous voltages.
Read Instructions: Before operating the transmitter read the instructions.
Retain Instructions: The safety precautions and operating instructions found in the Owner’s Manual should be retained
for future reference.
Heed Warnings: Follow all warnings on the transmitter, accessories (if any) and in this Owner’s Manual.
Follow Instructions: Observe all precautions and operating instructions. Failure to do so may result in personal injury or
damage to the transmitter.
Analyzer label
WARNING – Potential Explosion Hazard: The devices are not intended for use in atmospheres or with sample gas
streams containing oxygen concentration greater than 21 percent by volume (ambient air) and are only intended
for use in gases or gas mixtures classified as Class I, Div 1, Groups C and D hazardous locations or in non-
hazardous locations, when used in the United States or Canada.

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Maintenance
Serviceability: Except for replacing the oxygen sensor, there are no parts inside the analyzer for the operator to service.
Only trained personnel with the authorization of their supervisor should conduct maintenance.
WARNING- Substitution of Components May Impair Intrinsic Safety
Oxygen Sensor: DO NOT open the sensor. The sensor contains a corrosive liquid electrolyte that could be harmful if
touched or ingested, refer to the Material Safety Data Sheet contained in the Owner’s Manual appendix. Avoid contact with
any liquid or crystal type powder in or around the sensor or sensor housing, as either could be a form of electrolyte.
Leaking sensors should be disposed of in accordance with local regulations.
Troubleshooting: Consult the guidelines in Section 8 for advice on the common operating errors before concluding that
your analyzer is faulty. Do not attempt to service the analyzer beyond those means described in this Owner’s Manual.
Do not attempt to make repairs by yourself as this will void the warranty as per Section 10 and may result in electrical
shock, injury or damage. All other servicing should be referred to qualified service personnel.
Cleaning: The analyzer should be cleaned only as recommended by the manufacturer. Wipe off dust and dirt from the
outside of the unit with a soft damp cloth then dry immediately. Do not use solvents or chemicals.
Nonuse Periods: If the analyzer is equipped with a range switch advance the switch to the OFF position and disconnect
the power when the transmitter is left unused for a long period of time.
Installation
This analyzer has been constructed in compliance with:
EN 60079-0 : 2009
EN 60079-1 : 2007
EN 60079-11 : 2012
For USA and Canada
UL 913, 7th Edition
CSA C22.2 No. 157-92
It must be installed in accordance with :
EN 60079-14
For USA - NEC and Canada – CEC Standards
WARNING - Potential Explosion Hazard – See Warning in Section 4 – Features and Specifications
Gas Sample Stream: Ensure the gas stream composition of the application is consistent with the specifications and if in
doubt, review the application and consult the factory before initiating the installation. Note: In natural gas applications
such as extraction and transmission, a low voltage current is applied to the pipeline itself to inhibit corrosion of the
pipeline. As a result, electronic devices connected to the pipeline can be affected unless they are adequately grounded.
Contaminant Gases: A gas scrubber and flow indicator with integral metering valve are required upstream of the
analyzer to remove any interfering gases such as oxides of sulfur and nitrogen or hydrogen sulfide that can interfere with
measurement and cause reduction in the expected life of the sensor. Consult the factory for recommendations concerning
the proper selection and installation of components.
Expected Sensor Life: With reference to the publish specification, the expected life of all oxygen sensors is predicated
on the basis of typical oxygen concentration (air for % sensor), temperature (77°F/25°C) and pressure (1 atmosphere) in

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“normal” applications. Deviations from standard conditions will affect the life of the sensor. As a rule of thumb, sensor life
is inversely proportional to changes in the pressure and temperature.
Accuracy & Calibration: Refer to section 5 Operation.
Materials: Assemble the necessary zero, sample and span gases and optional components such as valves, coalescing or
particulate filters, and pumps as dictated by the application. Stainless steel tubing is essential for maintaining the integrity
of the gas stream for low % level analysis.
Operating Temperature: The sample must be sufficiently cooled before it enters the analyzer and any optional
components. A coiled 10 foot length of ¼” stainless steel tubing is sufficient for cooling sample gases as high as 1,800 ºF
to ambient. The recommended operating temperature is below 35 ºC. However, the analyzer may be operated at
temperature up to 45 ºC on an intermittent basis but the user is expected to accept a reduction in expected sensor life –as
a rule of thumb, for every degree ºC increase in temperature (above 25 ºC), the sensor life is reduced by approximately
2.5%.
Warning – Sample Stream entering unit must never exceed 50 0C
Heat: Situate and store the analyzer away from direct sources of heat.
Liquid and Object Entry: The analyzer should not be immersed in any liquid. Care should be taken so that liquids are
not spilled into and objects do not fall into the inside of the analyzer.
Handling: Do not use force when using the switches, knobs or other mechanical components. Before moving your
analyzer be sure to disconnect the wiring/power cord and any cables connected to the output terminals of the analyzer.
Sample Pressure and Flow
All electrochemical oxygen sensors respond to partial pressure changes in oxygen. The sensors are equally capable of
analyzing the oxygen content of a flowing sample gas stream or monitoring the oxygen concentration in ambient air (such
as a confined space in a control room or an open area around a landfill or bio-pond). The following is applicable to
analyzers equipped with fuel cell type oxygen sensors.
Inlet Pressure: For the analyzers designed to measure oxygen in a flowing gas stream, the inlet sample pressure must
be regulated between 5-30 psig. Although the rating of the SS tubing and tube fittings/valves itself is considerably higher
(more than 100 psig), a sample pressure of 5-30 psig is recommended for ease of control of sample flow.
The analyzer equipped with a sample system has designated SAMPLE and VENT ports. Connect SAMPLE gas to SAMPLE
and the vent to the VENT ports only.
Outlet Pressure: In applications where sample pressure is positive, the sample must be vented to an exhaust pipe at a
pressure less than the inlet pressure so that the sample gas can flow through the sensor housing. Ideally, the sample must
be vented to atmospheric pressure.
Note: The sensor may be used at a slight positive pressure (e.g., when sample is vented to a common exhaust where the
pressure might be higher than 1 atmosphere). However, the pressure at the sensor must be maintained at all times
including during the span calibration. This may be accomplished by using a back-pressure regulator at vent line of the
analyzer. The back-pressure regulated must be set less than 2 PSIG. For higher back-pressure requirements, consult
factory.
Caution: A sudden change in pressure at the sensor may result in the sensor electrolyte leakage.
Flow rates of 1-5 SCFH cause no appreciable change in the oxygen reading. However, flow rates above 5 SCFH may
generate a slight backpressure on the sensor resulting in erroneous oxygen readings.
Caution: Do not place your finger over the vent (it pressurizes the sensor) to test the flow indicator when gas is flowing
to the sensor. Removing your finger (the restriction) generates a vacuum on the sensor and may damage the sensor
(voiding the sensor warranty).
Application Pressure - Positive: A flow indicator with integral metering valve positioned upstream of the sensor is
recommended for controlling the sample flow rate between 1-2 SCFH. If necessary, a pressure regulator upstream of the

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flow control valve should be used to regulate the inlet pressure between 5-30 psig. Though the analyzer is designed to
handle inlet pressure up to 100 PSIG, 5-30 PSIG pressure range is recommended only for ease of control of sample flow.
Application Pressure - Atmospheric or Slightly Negative: For % oxygen measurements, an optional external sample
pump may be used upstream of the sensor to push the sample across the sensor and out to atmosphere or an eductor
pump downstream of the sensor to pull the sample across the sensor. If the sample pump can pull/push more than 5
SCFH, a flow meter with control valve must be used to control the sample flow. The flow control valve must be positioned
in such a way that it does not generate any vacuum on the sensor.
Caution: If the analyzer is equipped with a flow indicator with integral metering valve or a metering flow
control valve upstream of the sensor and the pump is installed downstream of sensor- open the metering valve
completely before turning the pump ON to avoid drawing a vacuum on the sensor and placing an undue
burden on the pump.
Mounting: The analyzer is approved for indoor as well as outdoor use. However, avoid mounting in an area where direct
sun might heat up the analyzer beyond the recommended operating temperature range. If possible, install a small hood
over the analyzer for rain water drain and to prevent over-heating of analyzer. If the ambient temperature is
expected to fall below -18 degree C (0 degree F), install the analyzer within an heated enclosure.
Gas Connections: The Inlet and outlet vent gas lines require 1/8” or ¼” stainless steel compression type tube fittings.
The sample inlet tubing must be metallic, preferably SS. The sample vent line may be of SS or hard plastic tubing with low
gas permeability.
Power: Supply power to the analyzer only as rated by the specification or markings on the analyzer enclosure. The GPR-
2500 AIS LD is powered by 12-28 VDC supply. The wiring that connects the analyzer to the power source should be
installed in accordance with recognized electrical standards. Ensure that the analyzer case is properly grounded and meets
the requirements for area classification where the analyzer is installed. Never yank wiring to remove it from a terminal
connection.
The maximum power the analyzer consumes is no more than 7 Watts.

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4. Features & Specifications

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5. Operation
Principle of Operation
The GPR-2500 AIS LD Oxygen Analyzer incorporates the GPR-11-32-LD or XLT-11-24-LD advanced galvanic fuel cell type
oxygen sensors. These sensors are very specific to oxygen and generate an electrical signal proportional to the amount of
oxygen present in a gas stream. The selection of a particular type of sensor depends on the composition of the sample gas
stream. Consult factory for recommendation.
The analyzer is configured in two sections. The signal processing electronics and sensor are housed in a general purpose
NEMA 4X rated enclosure. The terminals for incoming power, signal output and intrinsic safety barriers are mounted on a
PCB housed in an explosion proof enclosure.
The two sets of electronics are interconnected using an explosion proof Y-fitting, explosion proof packing fiber and sealing
cement – see Appendix A. Once connected, the intrinsic safety barriers limit the amount of power that flows to and from
the signal processing electronics effectively preventing an explosive condition. The analyzer design conforms to the ATEX
and UL directive for equipment as intrinsically safe and has been approved by an independent body:
The analyzer carries the following area classification
II 2 G
Ex d [ib] ib IIB T4 Gb
Tamb -20⁰C to +50⁰C
WARNING: POTENTIAL ELECTROSTATIC CHARGING HAZARD-SEE INSTRUCTION
For USA and Canada
UL 913, 7th Edition
CSA C22.2 No. 157-92
It must be installed in accordance with
EN 60079-14
For USA - NEC and Canada – CEC Standards
The GPR-2500 AIS also meets the intrinsic safety standards required for use in Class I, Division 1, Groups C, D hazardous
areas.
Advanced Galvanic Sensor Technology
All galvanic type sensors function on the same principle and are specific to oxygen. They measure the partial pressure of
oxygen from low PPM to 100% levels in inert gases, gaseous hydrocarbons, helium, hydrogen and mixed gases.
Oxygen, the fuel for this electrochemical transducer, diffusing into the sensor, reacts electrochemically at the sensing
electrode to produce an electrical current output proportional to the oxygen concentration in the gas phase. The sensor’s
signal output is linear over all measuring ranges and remains virtually constant over its useful life. The sensor requires no
maintenance and is easily and safely replaced at the end of its useful life.
Proprietary advancements in design and chemistry add significant advantages to this extremely versatile oxygen sensing
technology. Sensors recover from air to low % levels in seconds, exhibit longer life and reliable quality. The expected life
of our new generation of percentage range sensors now range from 32 months to ten years with faster response times

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and greater stability. Another significant development involves expanding the operating temperature range for percentage
range sensors from -20°C to 50°C. Contact factory for more specific information about your application.
NOTE- Check the product label for safe operating conditions
Electronics
The signal generated by the sensor is processed by state of the art low power micro-processor based digital circuitry. The
first stage amplifies the signal. The second stage eliminates the low frequency noise. The third stage employs a high
frequency filter and compensates for signal output variations caused by ambient temperature changes. The result is a very
stable signal. Sample oxygen is analyzed very accurately. Response time of 90% of full scale is less than 2 minutes (actual
experience may vary due to the integrity of sample line connections, dead volume and flow rate selected) on all ranges
under ambient monitoring conditions. Sensitivity is typically 0.5% of full scale of the low range. Oxygen readings may be
recorded by an external device via the 4-20 mA or 1-5V signal output.
Sample System
See Section 4, Features and Specification, Note 1 for exclusions.
The standard GPR-2500 AIS-LD is supplied with a sample flow-through sensor housing that allows the
moisture/condensable liquids to separate when the sample enters the sensor housing thus providing the user with hassle
free sample analysis despite the presence of liquid in the sample gas; see section 2 QC Certification for additional optional
equipment ordered.
The GPR-2500 AIS-LD is generally supplied with a sample flow control valve and a flow meter and sample/span selection
valve. Users interested in adding their own sample conditioning system should consult factory. Advanced Instruments Inc.
offers a full range of sample handling, conditioning and expertise to meet your application requirements. Contact us at
909-392-6900 or e-mail us at i[email protected]om.
Calibration & Accuracy Overview
Single Point Calibration:As previously described
the galvanic type oxygen sensor generates an electrical
current proportional to the oxygen concentration in the
sample gas. In the absence of oxygen the sensor
exhibits an absolute zero, e.g. the sensor does not
generate a current output in the absence of oxygen.
Given these linearity and absolute zero properties,
single point calibration is possible.
Pressure: Because sensors are sensitive to the partial
pressure of oxygen in the sample gas, their output is a
function of the number of molecules of oxygen 'per unit
volume'. Readouts in percent are permissible only when
the total pressure of the sample gas being analyzed
remains constant. The pressure of the sample gas and
that of the calibration gas must be the same.
Temperature: The rate at which oxygen molecules
diffuse into the sensor is controlled by a Teflon membrane otherwise known as an 'oxygen diffusion limiting barrier' and all
diffusion processes are temperature sensitive, the fact the sensor's electrical output will vary with temperature is normal.
This variation is relatively constant (2.5% per ºC). A temperature compensation circuit employing a thermistor and a
network of resisters offsets this effect with an accuracy of +5% or better over a wide operating temperature range e.g., 5-
45 oC can be obtained thus the signal output remains virtually independent of ambient temperature. There is extremely

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low error in measurement if the calibration and sampling are performed at similar temperatures (within +/- 5 ºC.
Conversely, a temperature variation of 10 ºC may produce an error of < 2% of full scale.
Accuracy: In light of the above parameters, the overall accuracy of an analyzer is affected by two types of errors: 1)
'percent of reading errors', illustrated by Graph A below, is contributed by the temperature compensation circuit
(tolerance in the thermistor value, variation in temperature coefficient of the thermistor, tolerances in resistors values and
the accuracy in the measuring devices, e.g., LCD display and 2) 'percent of full scale errors', illustrated by Graph B, such
as1-2% offset errors in readout and calibration devices. Other errors are 'spanned out' during calibration, especially when
analyzer is calibrated close to the top end of the measuring range.
Graph C illustrates these 'worse case' specifications that are typically used to develop an overall accuracy statement of <
1% of full scale at constant temperature or < 5% over the operating temperature range. The QC testing error is typically
< 0.5% prior to shipment of analyzer from the factory.
Example 1: As illustrated by Graph A, any error during a span adjustment at lower end of the scale, e.g., 20.9% (air) on
a 100% full scale range, would be multiplied by a factor of 4.78 (100/20.9) when making measurements close to 100%
O2. Conversely, an error during a span adjustment close to the top end of the range, e.g., at 100% is reduced
proportionately for measurements of oxygen concentrations near the bottom end of the range.
Graph B represents a constant error over the entire measuring range. This error is generally associated with the measuring
e.g., LCD and or calibrating devices, e.g., current simulator or current/voltage measuring devices.
Potential Explosion Hazard – See warning in Section 4 – Features and Specifications

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Mounting the Transmitter
The GPR-2500 AIS-LD analyzer consists of two interconnected enclosures. This configuration is designed to be mounted
directly to any flat vertical surface, wall or bulkhead plate by using four (4) of the appropriate mounting holes on the back
panel..
To facilitate servicing the interior of the transmitters, secure the back plate to a vertical surface approximately 5 feet from
the floor or a level accessible to service personnel. This requires the user to supply four (4) additional proper size screws
and anchors.
Caution: Do not remove or discard the gaskets from either the Ex enclosure or the fiberglass enclosure.
Failure to reinstall either of the gaskets will void the NEMA 4, UL Type 3R rating and the immunity to RFI/EMI.
The transmitters design provides immunity from RFI/EMI by maintaining a good conductive contact between
the two sections of the enclosures containing the main electronic signal processing PCB/display via a conductive gasket
(the smaller enclosure inside the fiber glass enclosure) The surfaces contacting the conductive gasket are unpainted. Do
not paint these areas. Painting will negate the RFI/EMI protection.
Note: The transmitter and sample system are mounted to a back panel 15-3/4”H x 15-3/4”W with four mounting holes.
Mount the entire panel to any vertical flat surface.

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Gas Connections
The GPR-2500 AIS-LD with its standard flow through configuration is designed for positive pressure samples and requires
connections for incoming sample and outgoing vent lines. A span inlet port is offered as part of the sample system. The
user is responsible for calibration gases and other required components, see below.
Procedure
Caution: Do not change the factory setting until instructed to do in this manual.
1. Regulate the sample pressure as described in “Pressure and Flow” section above.
2. Connect a ¼” vent line to the compression fitting to be used for venting the sample.
3. Connect a ¼” sample line to the compression fitting marked SAMPLE on the analyzer.
4. Connect the SPAN gas lines to the SPAN port of the analyzer.
5. Set the SAMPLE and SPAN gas pressure between 5-30 psig. Set the Sample and Span pressure within 5 PSIG to
ensure a relatively constant flow when switching Sample/Span gases
6. Use the span gas to set the flow rate for the sample as well by setting the three-way Sensor/ Flow Meter Span Bypass
valve to Flow Meter/Span Bypass and set the flow rate to 1- 2 SCFH. Do not use the sample containing liquid to set
the flow rate as liquid can damage the flow meter.
7. After setting the flow rate, switch the Sensor/ Flow Meter Span Bypass valve to Sensor and Sample/Span valve to
Sample or Span.
SAMPLE INLET
SPAN INLET
VENT
Picture View of Two Valve Configuration

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Electrical Connections
Incoming power/signal output
connections are made to terminal block
mounted on a PCB located in the
explosion proof enclosure.
Do not supply voltage more than specified in this
manual and noted near the power input terminal of
the analyzer.
The PCB in the explosion proof enclosure contains
a power limiting intrinsic safety barrier that limit
the total power available at the PCB electronics
mounted in the general purpose enclosure.
With proper insulation of the incoming power (see
Appendix A), this configuration of the GPR-2500
AIS-LD conforms to the ATEX directives for
equipments for use in hazardous area. The
analyzer meets the following area classification:
II 2 G
Ex d [ib] ib IIB T4 Gb
Tamb -20⁰C to +50⁰C
The GPR-2500 AIS-LD also meets the intrinsic safety standards required for use in Class I, Division 1, Group C, D
hazardous areas.
UL 913 Seventh Edition, Referencing UL 60079-0:2005 and UL 60079-11:2009 and CSA C22.2 No. 157-92 Third Edition
for use in Class I, Div 1, Groups C and D hazardous locations
The A-1166 AIS PCB in the Ex enclosure contains four safety fuses and one plug-in (brown color) rated at 200 mA, The
safety fuses meet barrier network standard EN 50020.
Avoid electrostatic discharge – Clean all surfaces with a damp cloth only.
Analyzer ground terminal must
be connected to a ground

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Hazardous Area Installation
The GPR-2500 AIS-LD may be installed in a hazardous area with proper insulation of the incoming power, see Appendix A.
A 12-28 VDC power supply with a shielded power cable is recommended. The power cable to the Ex enclosure must be
supplied through a conduit approved for use in hazardous area. Secure the wires to the power input terminal block by
using the integral screws of the terminal block. Do not substitute terminal screws.
CAUTION: Check the QC and the analyzer label for the proper power requirement. Incorrect power will
severely damage the analyzer
Power In/Signal Output Connections
The analyzer has one terminal for power in and 4-20 mA loop connections.
Power Source
12-28 VDC
Power IN, 4-20 mA Signal Signal Processing
Alarm Relays, MOD Bus interface
Explosion Proof Fiber Glass
Enclosure Enclosure
NOTE: There are five interconnecting wires between the explosion proof enclosure and the fiber glass enclosure, for
Clarity, only two wires are shown.
Procedure
Power requirements consist of a 12-28 VDC power supply.
1. Unscrew the cone shaped cover from the Ex enclosure.
2. Strip the end of wires no greater than 1/4 inch
3. Loosen the two screws of the terminal block. Insert the stripped end of the wires into the terminal block. Ensure the
positive and negative terminals of the power cable are connected to the terminals of the terminal block as marked.
4. Connect the Ground to the ground screw outside the enclosure.
5. Replace the cover.

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Installing the Oxygen Sensor
The GPR-2500 AIS-LD Oxygen Analyzer is equipped with a SS flow-through sensor housing. This housing offers ease of
replacement of sensor. The sensor simply screws into the sensor flow-through adaptor. After screwing the sensor into the
housing, remove the Molex connector on top of the sensor and connect the sensor cable to the sensor.
Caution: All analyzers must be
calibrated once the installation has been
completed and periodically thereafter as described
below. Following the initial installation and
calibration, allow the transmitters to stabilize for
12-24 hours and re-calibrate the transmitter with a
certified span gas.
Caution: DO NOT dissect the oxygen
sensor. The sensor contains a corrosive
liquid electrolyte that could be harmful
if touched or ingested, refer to the Material Safety
Data Sheet contained in the Owner’s Manual
appendix. Avoid contact with any liquid or crystal
type powder in or around the sensor or sensor
housing, as either could be a form of electrolyte.
Leaking sensors should be disposed off in a manner
similar to that of a common battery in accordance
with local regulations.
Avoid electrostatic discharge – Clean all
surfaces with a damp cloth only.
Procedure
1. Remove the two (2) clamps securing the right
side corners and open the door of the fiber
glass enclosure.
2. Remove the sensor cable from the sensor (if
the sensor has been previously installed)
3. Remove the old sensor (if previously installed) from the sensor housing
4. Remove the oxygen sensor from the bag.
5. Immediately screw the sensor into the sensor flow through adaptor.
6. Remove the Molex connector with red shorting wire from the sensor
7. Connect the sensor cable to the sensor
8. You may choose the option to "air calibrate" the sensor at this time (see details in "calibration") to ensure that the
analyzer accepts the air calibration and that the sensor output is within the recommended limits.
9. The analyzer electronics will respond immediately and display the oxygen contents (in air or flowing sample)
10. The sensor will trend down from air to low PPM levels within a few minutes.
11. Allow sensor to stabilize for a few hours and re-check the calibration with a span gas if required.

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Span Gas Preparation
See Section 4 – Features and Specifications, for exclusions if any
Note: The GPR-2500 AIS-LD can be calibrated by using ambient air. However, it can also be calibrated by using a certified
span gas. Air calibration can be achieved right after installing the sensor in the housing. Subsequent calibration, where the
sensor has been exposed to a sample gas, air calibration can be achieved by either removing the sensor from the sensor
housing or by pushing the air through the sensor housing.
Caution: Do not contaminate the span gas cylinder when installing the pressure regulator on the span gas
cylinder. Further, bleed the air filled regulator and span gas tubing before connecting the span gas to the
analyzer and attempting the initial calibration. A three way purge valve is highly recommended to purge the span line
before allowing the span gas to flow through the sensor housing.
Required Components
1. Certified span gas cylinder or compressed air with an oxygen concentration, balance nitrogen, approximating 80% of
the full scale of the measuring range or one range above the intended measuring range.
2. A pressure regulator to set the span gas pressure between 5-30 psig (set Span gas pressure with 2 PSIG of the
Sample gas to ensure relatively constant flow when switching from Sample/Span and vise-versa).
3. Suitable tube fittings and a 4-6 ft. length of metal tubing to connect the pressure regulator to the analyzer Span inlet
4. A three way valve to purge the Span gas line before allowing the span gas to enter the sensor housing.
Procedure
1. With the span gas cylinder valve closed, install the pressure regulator on the cylinder.
2. Open the regulator’s exit valve and partially open the pressure regulator’s control knob.
3. Open slightly the cylinder valve.
4. Loosen the nut connecting the regulator to the cylinder and bleed the pressure regulator.
5. Retighten the nut connecting the regulator to the cylinder
6. Adjust the regulator exit valve and slowly bleed the pressure regulator.
7. Open the cylinder valve completely.
8. Set the pressure between 5-30 psig using the pressure regulator’s control knob. The Span gas pressure should be
within 2 PSIG of the Sample pressure to ensure that when switching Span to Sample, the flow rate will be very similar
to that with Span gas.
Establishing Power to Electronics
Once power is supplied to the power terminals inside the Ex enclosure as described above, the digital display responds
instantaneously and performs several self-diagnostic system status checks termed as “START-UP TEST” as illustrated
below:
START-UP TEST
ELECTRONICS – PASS
TEMP SENSOR – PASS
BAROMETRIC SENSOR – PASS
REV.S1010.1.17