5 operations, Advanced instruments inc – Analytical Industries GPR-1900 Series Trace PPB Oxygen Analyzer User Manual
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Advanced Instruments Inc.
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5 Operations
Principle of Operation
The GPR-1900 ppm Oxygen Analyzer incorporates several advanced galvanic fuel cell type sensors for parts-per-million ppm
oxygen analysis. This model is configured for panel mounting and requires a 6”W x 3”H cutout with 4 holes for the studs located
on the back side of the analyzer’s front panel.
Optional mounting configurations include a 19” rack or wall mount enclosure with or without a sample system. Contact the
factory for additional information on options.
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.
Gas streams with acid gases like CO2 in the background in concentrations greater than 0.5% require the use of an XLT Series
oxygen sensor to maintain accuracy and reasonable sensor life.
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. 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. Another significant development involves expanding the operating temperature range for
percentage range sensors from -30°C to 50°C.
The GPR-1900 employs the GPR-12-333 or XLT-12-333 ppm oxygen sensor and a stainless steel sensor flow housing to provide
a very cost effective versatile ppm trace oxygen analyzer with four (4) standard ranges: 0-100 ppm, 0-1000 ppm, 0-1% for
analysis and 0-25% for air calibration (analysis is possible on this range provided the user can accept a drastic reduction in
expected sensor life). Under constant conditions the GPR-1900 is capable of analyzing 1 ppm or less.
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.
Additional features of the micro-processor based electronics include manual or auto ranging, isolated 4-20mA signal for signal
output and range ID. Whenever the analyzer is calibrated, a unique algorithm predicts and displays a message indicating a
‘weak sensor’ suggesting the sensor be replaced in the near future.
Users interested in adding their own sample handling or conditioning system are encouraged to consult the factory to ensure all
applicable conditions are addressed to ensure proper operation of the analyzer. 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 e-mail us at
Sample System
The GPR-1900 is designed to be integrated into a larger analyzer system and provide users with maximum flexibility, and,
therefore is not equipped with a sample system. The sample must be properly presented to the sensor to ensure an accurate
measurement. 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 e-mail us at
.