Analytical Industries GPR-1200 User Manual

Portable ppm Oxygen Analyzer

GPR-1200

Owner’s Manual

2855 Metropolitan Place, Pomona, CA 91767 USA ♦ Tel: [phone], Fax: [phone], e-mail: [e-mail], www.aii.com

10/09

Table of Contents

Introduction

1

Quality Control Certification
Safety
Specifications
Operation
Maintenance
Spare Parts
Troubleshooting
Warranty
Material Safety Data Sheets
Appendix C – Pump Options

2
3
4
5
6

7
8
9

10

1 Introduction

Your new portable oxygen analyzer incorporates an advanced electrochemical sensor specific to oxygen along with state-of-the­art digital electronics designed to give you years of reliable precise oxygen measurements in variety of industrial oxygen
applications. 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; and, 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 analyzer is your assurance that we stand behind every analyzer sold.

The serial number of this analyzer may be found on the inside the analyzer. 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.

2

2 Quality Control Certification

Date: Customer: Order No.: Pass
Model GPR-1200 Portable ppm Oxygen Analyzer S/N ____________________
Sensor ( ) GPR-12-333 ppm Oxygen Sensor

( ) XLT-12-333 ppm Oxygen Sensor S/N ____________________

Accessories Owner’s Manual
( ) PWRS-1002 9VDC Battery Charger/Adapter 110VAC

( ) PWRS-1003 9VDC Battery Charger/Adapter 220VAC
( ) PWRS-1008 9VDC Battery Charger/Adapter 12VDC Auto Cigarette Lighter

CONN-1034 Plug Mini Phone .141 dia. Black Handle
FITN-1003 (3x) Plug Male Quick Disconnect Fittings
TOOL-1001 5/16 Combination Wrench

Configuration A-1151-E-B1 PCB Assembly
Range: 0-10 ppm, 0-100 ppm, 0-1000 ppm, 0-25%
Wetted parts: stainless steel

Electronics Test LED indicators: Low battery, charge
Electronic offset
Analog signal output 0-1V

Gas Phase Test Recovery from air to < 10 ppm in < 1 hour
Baseline drift on zero gas < ± 2% FS over 24 hour period on 0-1% range
Noise level < ± 0.5% FS
Span adjustment within 10-50% FS
Final Overall inspection for physical defects

Options
Notes

3

3 General Safety & Installation

Safety

This section summarizes the basic precautions applicable to all analyzers. Additional precautions specific to individual analyzer
are contained in the following sections of this manual. To operate the analyzer 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.

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 analyzer 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 Instructions: Follow all warnings on the analyzer, accessories (if any) and in this Owner’s Manual.

Observe all precautions and operating instructions. Failure to do so may result in personal injury or damage to the analyzer.

Heat: Situate and store the analyzer away from 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 and knobs. Before moving your analyzer be sure to disconnect the

wiring/power cord and any cables connected to the output terminals located on the analyzer.

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.

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 this Owner’s Manual. 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 detailed by section 9, 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: Disconnect the power when the analyzer is left unused for a long period of time.

4

Installation

Gas Sample Stream: Ensure the gas stream composition of the application is consistent with the specifications and review the
application conditions before initiating the installation. Consult the factory to ensure the sample is suitable for analysis. Note: In
natural gas applications such as extraction and transmission, a low voltage current is applied to the pipeline itself to inhibit
corrosion. As a result, electronic devices can be affected unless adequately grounded.

Contaminant Gases: A gas scrubber and flow indicator with integral metering valve are required upstream of the of the
analyzer to remove interfering gases such as oxides of sulfur and nitrogen or hydrogen sulfide that can produce false readings,
reduce the expected life of the sensor and void the sensor warranty if not identified at time of order placement. Installation of a
suitable scrubber is required to remove the contaminant from the sample gas to prevent erroneous analysis readings and
damage to the sensor or optional components. Consult the factory for recommendations concerning the proper selection and
installation of components.

Expected Sensor Life: With reference to the publish specification located as the last page of this manual, the expected life of
all oxygen sensors is predicated on oxygen concentration (< 1000 ppm or air), temperature (77°F/25°C) and pressure (1
atmosphere) in “normal” applications. Deviations are outside the specifications and will affect the life of the sensor. As a rule of
thumb sensor life is inversely proportional to changes in the parameters.

Accuracy & Calibration: Refer to section 5 Operation.
Materials: Assemble the necessary zero, purge 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 ppm and percentage range (above or below ambient air) analysis; hardware for mounting.

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 1,800ºF to ambient. The
maximum operating temperature is 45º C on an intermittent basis unless the user is willing to accept a reduction in expected
sensor life – refer to analyzer specification - where expected sensor life is specified at an oxygen concentration less than 1000
ppm oxygen for ppm analyzers and air (20.9% oxygen) for percent analyzers, but in all instances at 25°C and 1 atmosphere of
pressure. Expected sensor varies inversely with changes in these parameters.

Pressure & 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 such in a control room or an open area such as a landfill or bio-pond). The following is applicable to analyzers equipped
with fuel cell type oxygen sensors. With respect to analyzers equipped with Pico-Ion UHP and MS oxygen sensors, refer to the
analyzer’s specifications.

Analyzers designed for in-situ ambient or area monitoring have no real inlet and vent pressure because the sensor is exposed
directly to the sample gas and intended to operate at atmospheric pressure, however, slightly positive pressure has minimal
effect on accuracy.

Inlet Pressure: Analyzers designed for flowing samples under positive pressure or pump vacuum (for samples at atmospheric
or slightly negative atmospheres) that does not exceed 14” water column are equipped with bulkhead tube fitting connections
on the side of the unit (unless otherwise indicated, either fitting can serve as inlet or vent) and are intended to operate at
positive pressure regulated to between 5-30 psig although their particular rating is considerably higher. Caution: If the
analyzer is equipped with an optional H2S scrubber, inlet pressure must not exceed 30 psig.

Outlet Pressure: In positive pressure applications the vent pressure must be less than the inlet, preferably atmospheric.
Sample system

other than ambient air. In these situations, the use of stainless steel tubing and fittings is critical to maintaining the integrity of
the gas stream to be sampled and the inlet pressure must always be higher than the pressure at the outlet vent which is
normally at atmospheric pressure. Flow Through Configuration: The sensor is exposed to sample gas that must flow or be

s and flowing gas samples are generally required for applications involving oxygen measurements at a pressure

5

drawn through metal tubing inside the analyzer. The internal sample system includes 1/8” compression inlet and vent fittings, a
stainless steel sensor housing with an o-ring seal to prevent the leakage of air and stainless steel tubing.

Flow rates of 1-5 SCFH cause no appreciable change in the oxygen reading. However, flow rates above 5 SCFH generate
backpressure and erroneous oxygen readings because the diameter of the integral tubing cannot evacuate the sample gas at
the higher flow rate. The direction the sample gas flows is not important, thus either tube fitting can serve as the inlet or vent –
just not simultaneously.

A flow indicator with an integral metering valve upstream of the sensor is recommended as a means of controlling the flow rate
of the sample gas. A flow rate of 2 SCFH or 1 liter per minute is recommended for optimum performance.

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). To avoid generating a vacuum on the sensor (as described above) during operation, always select and install
the vent fitting first and remove the vent fitting last.

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. To reduce the possibility of leakage for low ppm
measurements, position a metering needle valve upstream of the sensor to control the flow rate and position a flow indicator
downstream of the sensor. If necessary, a pressure regulator (with a metallic diaphragm is recommended for optimum
accuracy, the use of diaphragms of more permeable materials may result in erroneous readings) 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 accurate ppm range 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.

Caution: If the analyzer is equipped with an optional flow indicator with integral metering valve or a metering flow control
valve upstream of the sensor - open the metering valve completely 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.

Recommendations to avoid erroneous oxygen readings and damaging the sensor:

¾ 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 (thus voiding
the sensor warranty).

¾ Assure there are no restrictions in the sample or vent lines
¾ Avoid drawing a vacuum that exceeds 14” of water column pressure – unless done gradually
¾ Avoid excessive flow rates above 5 SCFH which generate backpressure on the sensor.
¾ Avoid sudden releases of backpressure that can severely damage the sensor.
¾ Avoid the collection of liquids or particulates on the sensor, they block the diffusion of oxygen into the sensor

- wipe away.

¾ If the analyzer is equipped with an optional integral sampling pump (positioned downstream of the sensor) and a flow

control metering valve (positioned upstream of the sensor), completely open the flow control metering valve to avoid
drawing a vacuum on the sensor and placing an undue burden on the pump.

6

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 optional
components. Moisture and/or particulates do not necessarily damage the sensor, however, collection 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 when in fact the problem is easily remedied by blowing on the front of the sensor. Consult the factory for
recommendations concerning the proper selection and installation of 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 following the cleaning process. Moisture and/or particulates generally can be removed from the
sample system by flowing the purge gas through the analyzer at a flow rate of 4.5-5 SCFH for an hour.

Mounting: The analyzer is approved for indoor use, outdoor use requires optional enclosures, consult factory. Mount as
recommended by the manufacturer.

Gas Connections: Inlet and outlet vent gas lines for ppm analysis require 1/8” or ¼” stainless steel compression fittings; hard
plastic tubing with a low permeability factor can be used percentage range measurements.

Power: Supply power to the analyzer only as rated by the specification or markings on the analyzer enclosure. The wiring that
connects the analyzer to the power source should be installed in accordance with recognized electrical standards. Ensure that is
properly grounded and meets the requirements for area classification. Never yank wiring to remove it from a terminal
connection. AC powered analog analyzers consume 5 watts, digital analyzers 50 watts without optional heaters. Optional 110V
and 220V heaters AC powered heaters consume an additional 100-150 watts; DC powered digital analyzers consume 30 watts,
40 watts with the optional DC powered heater.

7

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4 Specifications *

Accuracy: < 1% of FS range under constant conditions
Analysis Ranges: 0-10 ppm, 0-100, 0-1000 ppm, 0-1% plus 0-25% FS ran

Application:

Approvals: CE, Intrinsic Safety (pendin

Area Classification: Meets standards for Class 1, Division 1, Group C, D

Calibration: Certified gas of O

Compensation: Temperature and barometric pressure
Connections: 1/8" compression tube fittings
Controls: Water resistant keypad; menu driven ran

Display: Graphical LCD 2.75 x 1.375”; resolution .01 ppm; displays

Enclosure: Painted aluminum NEMA 4X, 8.6 x 9 x 3", 12 lbs.
Flow Sensitivity: None between 0.5-5 SCFH, 2 SCFH recommended
LED Indicators: LOW BATT (72 hr. warning); CHARGE mode

Linearity: > .995 over all ranges
Pressure: Inlet - regulate to 5-30 psig; vent - atmospheric
Power: Rechargeable battery, 60 day duty cycle (pump 1 day)
Recovery Time: 60 seconds in air to < 10 ppm in < 1 hr on N
Response Time: 90% of final FS reading in 10 seconds
Sample System: Flow control and sample/bypass v a lves; flow indicator
Sensitivity: < 0.5% of FS range
Sensor Model: GPR-12-333
Sensor Life: 24 months at 25ºC, 1 atm and average O
Signal Output: 0-1V

Temp. Range: 5º to 45ºC (GPR sensor), -20º to 45ºC (XLT sensor)
Warranty: 12 months analyzer; 12 months sensor
Wetted Parts: Stainless steel

Optional Equipment

XLT-12-333 sensor with > 0.5% CO
Integral sampling pump - general purpose or intrinsically safe designs
Carrying case with custom foam insert
Sample conditioning accessories - contac t factory

* Specifications subject to change without notice

for air calibration; auto-ranging or lock on single range

nalyze oxygen concentrations from 100 ppb to 1% in inert,
hydrocarbon, helium, hydrogen, mixed and acid (CO
streams

purpose sampling pump)

hazardous areas (void with optional general purpose pump)

balance N2 approximating 80% of analysis

range or one range above analysis range

calibration and system functions

real time ambient temperature and pressure

2

present

2

, void with optional general

purge

2

< 1,000 ppm

2

) gas

2

e selection,

e

GPR-1200

Portable ppm O2 Analyzer

Advanced Sensor Technology
Accuracy < 1% FS Range
Sensitivity < 0.5% FS Range
Fast Recovery to < 10 ppm
24 Month Expected Life
No Maintenance
Compatible in 0-100% CO

Intrinsically Safe Design
Auto or Manual Ranging
4 Standard Analysis Ranges
0-25% Range for Air Calibration
SS Bypass Sample System
ISO 9001:2008 Certified QA System

Integral bypass sample system increases productivity.

2

8

5 Operation

Principle of Operation

The GPR-1200 portable oxygen analyzer incorporates a variety of ppm range advanced galvanic fuel cell type sensors. The
analyzer is configured in a general purpose NEMA 4 rated enclosure and meets the intrinsic safety standards required for use in
Class 1, Division 1, Groups A, B, C, D hazardous areas. Two integral sampling pump options are available – one that meets the
intrinsic safety standards and a less expensive option for general purpose service.

Advanced Galvanic Sensor Technology

The sensors function on the same principle and are specific for oxygen. They measure the partial pressure of oxygen from low
ppm to 100% levels in inert gases, gaseous hydrocarbons, helium, hydrogen, mixed gases, acid gas streams and ambient air.
Oxygen, the fuel for this electrochemical transducer, diffusing into the sensor reacts chemically 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 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 an extremely versatile oxygen sensing
technology. Sensors for low ppm analysis recover from air to ppm levels in minutes, exhibit longer life, extended operating
range of -20°C to 50°C, excellent compatibility with CO
significant advantage over the competition.

The expected life of our new generation of percentage range sensors now range to five and ten years with faster response
times and greater stability. Other significant developments involve the first galvanic oxygen sensor capability of continuous
oxygen purity measurements and expanding the operating temperature range from -40°C to 50°C.

and acid gases (XLT series) and reliable quality giving them a

2

9

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
monitoring conditions. Sensitivity is typically 0.5% of full scale low range. Oxygen readings may be recorded by an external
device via the 0-1V signal output jack.

Power is supplied by an integral rechargeable lead acid battery which provides enough power to operate the analyzer
continuously for approximately 60 days. An LED located on the front panel provides a blinking 72 hour warning to recharge the
battery. A 9VAC adapter (positive pole located on the inside of the female connector) can be used to recharge the battery from
a 110V or 220V convenience outlet. The analyzer is designed to be fully operational during the 8-10 hour charging cycle which
is indicated by a second continuously lit LED.

Sample System

The GPR-1200 is supplied with a unique bypass sample system which enables the user to isolate the sensor from exposure to
high oxygen concentration which results in a substantial increase is user productivity. However the sample must be properly
presented to the sensor to ensure an accurate measurement.

For ppm trace oxygen measurements, the sensor is exposed to sample gas that must flow or be drawn through the analyzer’s
internal sample system. This unique sample system, when operated accordingly to the instructions in this Owner’s Manual, can
significantly increase user productivity by minimizing the sensor’s exposure to ambient air or high oxygen concentrations which
contribute to the significant amount of downtime associated with competitive analyzers.

As illustrated above, the GPR-1200’s internal sample system includes:

¾ 1/8” tube fittings for the inlet and outlet
¾ flow control metering valve
¾ 4-way sample/bypass valve to purge lines and isolate the sensor
¾ Stainless steel sensor housing with an o-ring seal to prevent the leakage of air
¾ Flow indicator common to bypass and sample lines

Users interested in adding their own sample conditioning system should consult the factory. Advanced Instruments Inc. offers a
full line of sample handling, conditioning and expertise to meet your application requirements. Contact us at 909-392-6900 or e­mail us at [e-mail]

10

Accuracy & Calibration

Single Point Calibration: As previously described the
galvanic oxygen sensor generates an electrical current
proportional to the oxygen concentration in the sample gas.

Absolute Zero: 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(es) must be the same (reality < 1-2 psi).

Temperature: The rate 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 offsets this effect with an accuracy of better than +
entire Operating Range of the analyzer) and generates an output function that is independent of temperature. There is no error
if the calibration and sampling are performed at the same temperature or if the measurement is made immediately after
calibration. Lastly, small temperature variations of 10-15º produce < 1% error.

Accuracy:

producing 'percent of reading errors', illustrated by Graph A below, such as +5% temperature compensation circuit, tolerances
of range resistors and the 'play' in the potentiometer used to make span adjustments and 2) those producing 'percent of full
scale errors', illustrated by Graph B, such as +
technology and the fact that other errors are 'spanned out' during calibration. Graph C illustrates these 'worse case'
specifications that are typically used to develop an transmitter's overall accuracy statement of < 1% of full scale at constant
temperature or < 5% over the operating temperature range. QC testing is typically < 0.5% prior to shipment.

Example: As illustrated by Graph A any error, play in the multi-turn span pot or the temperature compensation circuit, during
a span adjustment at 20.9% (air) of full scale range would be multiplied by a factor of 4.78 (100/20.9) if used for
measurements of 95-100% oxygen concentrations. Conversely, an error during a span adjustment at 100% of full scale range is
reduced proportionately for measurements of lower oxygen concentrations.

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

1-2% linearity errors in readout devices, which are really minimal due to today's

5% (over the

11