Analytical Industries GPR-1535 GB Trace PPM Oxygen Transmitter - Manual (Page 7)

Advanced Instruments Inc.
7
5 Operation
Principle of Operation
The GPR-1535 GB incorporates a variety of ppm range advanced galvanic fuel cell type sensors. The transmitter 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 C, D hazardous areas when operated in conjunction with the manufacturer’s recommended intrinsic safety barriers.
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 and reliable quality. 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.
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.
A 4-20mA signal output is provided from a two-wire 12-28VDC loop power source such as a PLC and is represented on full scale
oxygen readings to an external device. When operated in conjunction with the manufacturer’s recommended optional intrinsic
safety barriers the GPR-1535 GB meets the intrinsic safety standards required for use in Class 1, Division 1, Groups C, D
hazardous areas.
The GPR-1535 GB is also available in a version, requiring optional intrinsic safety barriers, that has been certified to ATEX
Directive 94/9/EC, Ex II 1 G Ex ia IIB T4 Tamb -20⁰C to + 50⁰C
Sample System:
The GPR-1535 GB is supplied with a unique Glove Box Housing Assembly that also includes a mounting bracket for sampling
(see photo section 4 Specifications) and flow housing with valves for calibration.
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
[email protected]