Owner's manual

Advanced Instruments Inc.
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Oxygen, the fuel for this electrochemical transducer, 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 four ranges and
remains virtually constant over its useful life. The sensor requires no maintenance or electrolyte addition and is easily and safely
replaced at the end of 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
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, auto-zero and auto-cal, isolated 4-
20mA signal for signal output and range ID, separate relay contacts rated 30VDC max @ 1A are provided for the alarm feature
and an optional range ID feature (auto-zero/auto-cal with relay contacts for Range ID is special order, so . 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.
Sample System
The sample must be properly presented to the sensor to ensure an accurate measurement. In standard form the GPR-1600MS
is designed with a sample system that complements the performance capabilities of the Pico-Ion oxygen sensor and enables the
user to isolate the sensor from exposure to high oxygen concentration which results is a substantial increase is user
productivity. This bypass feature has two important features: one, the sensor can be isolated from exposure to high oxygen
levels when changing sample lines, during transport and during standby intervals making it ideal for mobile cart applications.
Two, it enables the user to purge newly connected gas lines of the oxygen trapped inside. The result is an analyzer that comes
on-line at ppb levels in a matter of minutes and provides users with a significant increase in productivity.
For ppb and 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.
The advantages of the bypass sample system include:
¾ Supplying the analyzer with the sensor it was qualified with.
¾ Isolating the sensor during transport, calibration and maintenance intervals when changing gas line connections.
¾ Isolating the sensor from exposure to high oxygen levels during upset conditions which extends sensor life.
¾ Purging the air (or high oxygen levels above 1,000 ppm) trapped in the gas lines following a process upset.
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 [e-mail]