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

Technical Specifications *

Accuracy: < 2% of FS range under constant conditions

Analysis: 0-10, 0-100, 0-1000 PPM, 0-1%, 0-25% (CAL) FS

Auto-ranging or manual lock on a single range

Application: Oxygen analysis in inert, hydrocarbon, helium, hydrogen,

mixed and acid (CO2) gas streams

Area Classification: General purpose
Calibration: 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.

Compensation: Temperature
Connections: 1/8" compression tube fittings
Controls: Water resistant keypad; menu driven range selection,

calibration and system functions

Display: Graphical LCD 2.75” x 1.375”; resolution 0.01 PPM; dis-

plays real time ambient temperature and pressure

Enclosure: Fiberglass NEMA 4X, 6.75 x 8.375 x 4.25", 10 lbs.
Flow Sensitivity: Not flow sensitive, 1-2 SCFH recommended

Linearity: ±1% of full scale
Pressure: Inlet - regulate to 5-30 psig to deliver 1-2 SCFH flow;

vent - atmospheric

Power: 18-24 VDC
Recovery Time: 30 seconds in air to < 10 PPM in < 1 hour on N2 purge

Response Time: 90% of final reading in 10 seconds
Sample System: None

Sensitivity: < 0.5% of FS range

GPR-1500 N

PPM Oxygen Transmitter

2 Wire Loop Powered O2 Transmitter

with Optional Sample Systems

Advanced Sensor Technology

 Fast Recovery to < 10 ppm

 Excellent Compatibility in 0-100% CO

 Extended Operating Temperature –10⁰C

18-28 VDC Loop Power

2

Sensor Model: GPR-12-333 for non-acid (CO2) gas streams;

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

4-20 mA Signal Output
Sensitivity 0.5% Full Scale

Sensor Life: 24 months in < 1000 PPM O2 at 25ºC and 1 atm
Signal Output: 4-20mA non-isolated

Operating Range: 5°C to 45°C (GPR sensor), -10°C to 45°C (XLT sensor)

Warranty: 12 months analyzer; 12 months sensor

Wetted Parts: Stainless steel

Optional Equipment

Sample conditioning system - Contact factory.

* 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

5 Ranges Standard
Auto Ranging or Single Fixed
Stainless Steel Wetted Parts

ISO 9001:2008 Certified

INTERTEK Certificate No. 485

Advanced Instruments Inc.

GPR-1500N

PPM Oxygen Transmitter

Shown with optional Sample Panel

Owner’s Manual

Revised August 2013

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

Advanced Instruments Inc.

Introduction

1 Quality Control Certification

2

Safety

3 Features & Specificat io n s

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

Correlating readings – LCD display to 4-20mA signal

The appendices referenced above are an integral part of the documentation, installation and maint enance of this
analyzer to comply with all applicable directives. It is important that users review these documents before proc eeding.

Appendix B

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1. Introduction

Your new oxygen transmitter i ncorporates an advanced electrochemical sensor specific to oxygen along with state-of­the-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 intrinsically safe in accordance with ATEX Directives
94/9/CE for use in hazard ou s areas in zone 1 Group C and D when used in conjunction with the recommend ed intri nsi c
safety barrier MTL7706+ or equivalent. The transmitter meets the following area classification.

Analytical Industries Inc.
dba Advanced Instruments Inc.
2855 Metropolitan Place, Pomona, CA 91767 USA

GPR-1500/2500

0080

Serial No.:
Year of Manufacture:
INERIS 08ATEX0036

II 1 G
Ex ia IIB T4
T

-20⁰C to +50⁰C

amb

WARNING: POTENTIAL ELECTROSTATIC CHARGING HAZARD – SEE INSTRUCTIONS

The design also meets NEC intrinsic safety standards for use in Class 1, Division 1, Group C, D hazardous areas.
Please refer to Appendix A for information on making electrical connections that maintain the desired level of
protection.

To obtain maximum performance from your new oxygen transmitter, 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
transmitter for superior performance and minimal cost of ownership. This transmitter 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 transmitter may be found on the inside the transmitter 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.

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Advanced Instruments Inc.

3. General Safety & Installation

This section summarizes the essential precautions applicable to the GPR-1500N/2500N Oxygen Transmitter.
Additional precautions specific to individual transmitter 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 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.

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Maintenance

Serviceability: Except for replacing the oxygen sensor, there are no parts inside the transmitter for the operator to
service.

Only trained personnel with the authorization of their supervisor should conduct maintenance.

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 guideli nes in Sect ion 8 for advice on the com mon oper atin g err ors before concluding
that your transmitter is faulty. Do not attempt to service the transmitter 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 transmitter should be cleaned only as recommended by the manufactur er. 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 transmitter is equipped with a POWER 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 : 2006
EN 60079-1 : 2004
EN 60079-11 : 2007

It must be installed in accor dance with

EN 60079-14

Gas Sample Stream: Ensur e the gas strea m com pos iti on of the appli cat ion is con si ste nt w ith the specif ic atio ns 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 publi sh spe cif i cati on loca ted at th e last page of thi s 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.

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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 very low % or PPM O

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%.

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.

level analysis.

2

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) . T he follow ing is applic able
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 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.

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 (voiding the sensor warranty).

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Advanced Instruments Inc.

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 valv e 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 measure ment s, an

optional external sample pump may be used upstream of the sensor to pu sh the sam ple acr oss the sen sor and out to
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- op en the meter ing
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 provide 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/particulate 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 at ion 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 the 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-heating of analyzer..

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-1500N/2500N is a two wire loop powered analyzer. To comply with the ATEX Directives 94/9/CE, power to the
transmitter must be provided via an approved intrinsic safety barrier MTL 7706+ or equivalent. WARRNING:

TRANSMITTER RATING FOR USE IN HAZARDOUS AREA WILL VOID W ITHOUT THE USE OF INTRINSIC
SAFETY BARRIER The input power must be between 24-28 VDC. 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 two wire loop powered analyzers consume no more than 0.68 Watts of power.

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4. Features & Specifications

8

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5. Operation
Principle of Operation

The GPR-1500N Oxygen Transmitter 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 signal processing electronics and sensor are housed in a general purpose NEMA 4X rated enclosure. The
terminals for incoming power and the signal output are provided in a small aluminum enclosure mounted on the side of
the large fiber glass enclosure.

The analyzer design conforms to the ATEX Directive 94/9/CE for equipment as intrinsically safe when used in
conjunction with an intrinsic safety barrier MTL7706+ or equivalent and has been approved by an independent body:
EC Type Examination Certificate: INERIS 08ATEX0036

The analyzer when used in conjunction with the intrinsic safety barrier carries the follow ing area cla ssif ic ati on

II 2 G,
Ex ia IIB T4,
T

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

-20⁰C to +50⁰C

amb

WARNING: POTENTIAL ELECTROSTATIC CHARGING HA ZAED- SEE INSTRUCTION

9

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 ou tput 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 mont hs 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.

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.

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 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 monitor ing con diti on s. 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.

Advanced Instruments Inc.

Sample System:

The standard GPR-1500N 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 sen sor
to ensure an accurate measurement.

The GPR-1500N 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 909­392-6900 or e-mail us at

[e-mail].

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Calibration & Accuracy Overview

Single Point Calibration: A s prev ious ly
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

5% or better over a wide operating temperature range e.g., 5-45 oC can be obtained thus the signal output remains

of +
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 error of < 2% of full scale.

Accuracy:

'percent of reading errors', illustrated by Graph A below, is contribu ted by the temperature compensation
(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 er r ors', 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 analyz er 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 mea sure ment s clo se to
100% O2. Conversely, an error during a span adjustment clo se 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.

In light of the above parameters, the overall accuracy of an analyzer is affected by two types of errors: 1)

circuit

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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 devic es, e.g., current simulator or current/volt age m easur ing dev ic es.

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Mounting the Transmitter

The GPR-1500N analyzer consists of two intercon nec ted en clo sure s (w ithout t he opti ona l sam ple conditioning system
and panel) and measures 8”H x 15-3/4”W x 7”D. This configuration is designed to be mounted directly to any flat
vertical surface, wall or bulkhead plate by using four (4) mounting feet supplied separately.

Sample In and

Secure 4 feet to the
enclosure and
mount the enclosure
on a flat surface

To facilitate servicing the interior of the transmitters, secure the transmitter 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.

To mount the transmitter, first secure four feet provided separately on four corners of the enclosure. Then use four
mounting screws/anchors and install the transmitter on a smooth vertical flat surface/wall.

Caution: Do not remove or discard the gaskets from the enclosure. Failure to reinstall the gaskets will void
the NEMA 4 rating and the im muni ty to RFI/EMI.

The transmitters design provides immunity from RFI/EMI by maintaining a good conductive contact between the two
halves of the enclosures via a conductive gasket (the smaller enclos ure cont ain ing. The surfaces contacting the
conductive gasket are unpainted. Do not paint these areas. Painting will negate the RFI/EMI protection.

Sample Out

13