Analytical Industries Inc (AII) GPR-1500 AIS Operating Manual

Technical Specifications *

Accuracy: < 2% of FS range under constant conditions
Analysis:

Application:

Approvals: Certified for use in hazardous areas - see lower right

Area Classification: Certified for use in hazardous areas - see lower right
Alarms:

Calibration:

Compensation:

Connections: 1/8" compression tube fittings
Controls:

Display:

Enclosure:

Flow: Not flow sensitive; recommended flow rate 1-2 SCFH
Linearity: ±2% of full scale
Pressure:

Power:

Response Time: 90% of final reading in 10 seconds
Sample System: Sample flow meter; options available, see other side

Sensitivity: < 0.5% of FS range
Sensor Model:
Sensor Life: 24 months in < 1000 PPM O2 at 25ºC and 1 atm

Signal Output:

Operating Range: 5º to 45ºC (GPR sensor); -10ºC to 45ºC (XLT sensor)
Warranty: 12 months analyzer; 12 months sensor

Wetted Parts: Stainless steel

Optional Equipment

0-10, 0-100, 0-1000 PPM, 0-1%, 0-25% (CAL) FS
Auto-ranging or manual lock on a single range

Oxygen analysis in inert, hydrocarbon, helium, hydro­gen, mixed and acid (CO2) gas streams

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

Two user configurable alarms: magnetic coil relays
rated 3A at 100 VAC, programmable alarm delays,
alarm bypass for calibration and system fail alarm

Max interval—3 months. Use certified span gas with
O2 content (balance N2) approximating 80% of full
scale for fast 20-30 minute recovery to online use.
Alternatively, air calibrate with clean source of com­pressed or ambient (20.9% O2) air on 0-25% range
and allow 60 minutes on zero gas to recover to 10
ppm. For optimum accuracy, calibrate one range high­er than the range of interest.

Barometric pressure and temperature (ATEX)
Temperature (UL)

Water resistant keypad; menu driven range selection,
calibration and system functions

Graphical LCD 2.75” x 1.375”; resolution 0.01 PPM;

displays real time ambient temperature and pressure
NEMA Type 3R for rain in outdoor applications (UL)

NEMA 4X (ATEX)

Inlet - regulate to 5-30 psig to deliver 1-2 SCFH flow;
vent - atmospheric

12-28 VDC (cUL and ATEX Certified)
110-220 VAC (ATEX Certified)

XLT-12-333 for gases containing > 0.5% CO2

4-20mA non-isolated or 1-5V; optional Modbus RTU
communication

cUL & ATEX Certified for Hazardous Areas

GPR-1500 AIS

PPM Oxygen Analyzer

Full Featured PPM Oxygen Analyzer with

Optional Modbus RTU Communication and

Modular Natural Gas Sample Systems

Exia

UL Certified

File E343386

Class I, Division 1, Groups C and D

T4 T

ATEX Certified - Directive 94/9/EC

Examination Cert: INERIS 08ATEX0036

II 2 G
Ex d ib IIB T4 Gb

T

-20⁰C to +50⁰C

amb

-20⁰C to +50⁰C

amb

0080

Sample conditioning systems (see back page) - Contact factory
GPR-12-333 sensor for non-acid (CO2) gas streams

* Specifications subject to change without notice

2855 Metropolitan Place, Pomona, CA 91767 USA ♦ Tel: [phone], Fax: [phone], www.aii1.com, e-mail: [e-mail] Rev 10/15

ISO 9001:2008 Certified

INTERTEK Certificate No. 485

Advanced Instruments Inc.

GPR -1500 AIS

PPM OXYGEN ANALYZER

Shown with optional Sampling System

Owner's Manual

Revised August 2013

2855 Metropolitan Place, Pomona, California 91767 USA ♦ Tel: [phone], Fax: [phone], e-mail:
[e-mail]

Introduction

1 Quality Control Certification

2

Safety

3 Features & Specificatio ns

4

Operation

5 Maintenance

6

Spare Parts

7 Troubleshooting

8

Warranty

9 Material Safety Data Sheets

10

Drawings

A/R

Explosion Proofing Electrical Connections

Appendix

A

output

H2S Scrubber, Sample System, Media MSDS

Appendix F Maintenance H2S Scrubber & Coalescing Filter

Appendix

G

Table of Contents

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Correlating readings – LCD display to 4-20mA signal

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.

Appendix B

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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 accord anc e 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 mater ial s and com po nents, 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-1500 AIS/2500 AIS

0080

Serial No.:
Year of Manufacture:
INERIS 08ATEX0036

II 2 G
Ex d ib IIB T4 Gb
T

-20⁰C to +50⁰C

amb

WARNING: POTENTIAL ELECTROSTATIC CHARGING HA ZARD – SEE
INSTRUCTIONS

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3. General Safety & Installation

This section summarizes the essential precautions applicable to the GPR-1500 AIS Oxygen Analyzer. Additional
precautions specific to individu al trans mitter are 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 immed iate 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 ULc

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 non­hazardous locations, when used in the United States or Canada.

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2. Quality Control Certification

5

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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 oper atin g er ror s befor e 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, 7
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 compon ent s.

Expected Sensor Life: With reference to the publish specification lo cate d at the last page of this manual, the

expected life of all oxygen sensors is predicated on oxygen concentration (< 1000 ppm for PPM sensor or air for %
sensor), temperature (77°F/25°C) and pressure (1 atmosphere) in “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 nece ssary zero, sa mpl e 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 % or PPM O

th

Edition

level analysis.

2

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Advanced Instruments, Inc

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 i s 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

0

C

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.

Analyzers designed for in-situ ambient or area monitoring has no real sample inlet and vent. The sensor is exposed directly
to the sample gas and it is intended to operate at atmospheric pressure. The analyzer has a built-in pressure sensor and
the sensor output is automatically compensated for any atmospheric pressure changes.

Inlet Pressure: For the analyz ers 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 consi der a bly
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.

Caution: If the analyzer is equipped with an optional H2S scrubber, sample inlet pressure must not exceed 30
psig.

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. 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 (voidi ng
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 1-5 SCFH. If a separate flow control valve and a flow
indicator is used, position flow control valve upstream of the sensor and position a flow indicator downstream of the sensor.
If necessary, a pressure regulator upstream of the flow control valve should be used to regulate the inlet pressure between
5-30 psig.

Caution: If the analyzer is equipped with a H2S scrubber as part of an optional sample conditioning system,
inlet pressure must not exceed 30 psig.

Application Pressure - Atmospheric or Slightly Negative: For % oxygen measurements, an

optional external sample pump may be used upstream of the sen sor to pu sh the sam ple acr oss the sensor and out to

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atmosphere. For PPM oxygen measurements, an optional external sampling pump should be positioned downstream of
the sensor to draw the sample from the process, by the sensor and out to atmosphere. A flow meter is generally not
necessary to obtain the recommended flow rate with most sampling pumps. However, if the sample pump can pull/push
more than 5 SCFH, a flow control 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.

If pump loading is a consideration, a second throttle valve on the pump’s inlet side may be necessary to provid e a bypass
path so the sample flow rate is within the above parameters.

Moisture & Particulates: Installation of a suitable coalescing or particulate filter is required to remove

condensation, moisture and/or particulates from the sample gas to prevent erroneous analysis readings and damage to the
sensor or other optional components. Moisture and/or particulates do not necessarily damage the sensor. However,
collection of moisture/part icu la te on the sensing surface can block or inhibit the diffusion of sample gas into the sensor
resulting in a reduction of sensor signal output – and the appearance of a sensor failure. Consult the factory for
recommendations concerning the pro per sel ect ion and in stal l ation of optional components.

Moisture and/or particulates generally can be removed from the sensor by opening the sensor housing and either blowing
on the sensing surface or gently wiping or brushing the sensing surface with damp cloth. Caution: Minimize the exposure
of PPM sensors to air during this cleaning process. Air calibration followed by purging with zero or a gas with a low PPM
oxygen concentration is recommended after t he cleaning process is completed.

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-heat ing of analyz er .

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 l ow gas permeability.

Power: Supply power to the analyzer only as rated by the specification or markings on the analyzer enclosure. The

GPR-1500 AIS 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 ana lyz er 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

Advanced Instruments, Inc

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*WARNING - Potential Explosion Hazard : The devices are not intended for use in atmosphere or with sample gas

streams containing more than 21% oxygen (ambient air) and are only intended for use with or in gases or gas mixtures
classified as Class I, Div 1 Groups C and D hazardous location gases or in non-hazardous loca tion s when used in the
United States or Canada.

**NOTE 1: Optional Sampling system shown is not part of UL/cUL Classification.

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5. Operation
Principle of Operation

The GPR-1500 AIS Oxygen Analyzer incorporates a variety of 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 the
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
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 IIB T4 Gb
T

For USA and Canada
UL 913, 7th Edition
CSA C22.2 No. 157-92

It must be installed in accordanc e with
EN 60079-14
For USA - NEC and Canada – CEC Standards

The GPR-1500 AIS also meets the intrinsic safety standards required for use in Class I, Division 1, Groups C, D hazardous
areas.

-20⁰C to +50⁰C

amb

WARNING: POTENTIAL ELECTROSTATIC CHARGING HA ZARD-SEE INSTRUCTION

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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, hydr ogen and mix ed gases

s 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 for low % analysis 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 and greater stability. Another significant development involves expanding the operating temperature range
for percentage range sensors from -30°C to 50°C. Contact factory for more specific information about your application.

NOTE- Check the product label for safe operating conditions

The PPM sensors recover from an upset condition to low PPM level in a matter of few minutes. These sensors show
excellent stability over its useful life.

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Electronics

The signal generated by the sensor is processed by state of the art low power micro-proce ssor ba sed 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 10 seconds
(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.

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Sample System

See Section 4, Features and Specification, Note 1 for exclusions.
The standard GPR-1500 AIS is supplied without a sample conditioning system thereby giving users the option of adding

their own or purchasing a factory designed sample conditioning system, see section 2 QC Certification for optional
equipment ordered. Whatever the choi ce, the sa mple must be properly conditioned before introducing it to the sensor to
ensure an accurate measurement.

The GPR-1500AIS is generally supplied with a minimum of a sample flow control valve and a flow meter. Users interested
in adding their own sample conditioning system should consult the 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

[e-mail].

us at

Calibration & Accuracy Overview

Single Point Calibration: A s prev ious ly descri bed 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 sensitiv e 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 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 err or
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
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 as1­2% 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.

13

circuit (tolerance