Analytical Industries GPR-2900 Series Oxygen Analyzer - Manual (Page 11)

Advanced Instruments Inc.
11
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 (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.
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.
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.
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 Connection: Locate the appropriate source of to meet the analyzer or analyzer requirements, ensure that is properly
grounded and meets the area classification.
Mounting the Analyzer & Sensor:
The GPR-2900 consists of a six (6) foot insulated cable which
connects the sensor to the rear of the electronics module, a long
life maintenance free oxygen sensor and a sensor flow housing
equipped with 1/8” diameter stainless steel compression fittings.
The compact design also lends itself to optional mounting
configuration such as a standard 19” rack or wall mount
enclosures, both of which can be equipped with optional sample
system components. Contact the factory for additional information.
Procedure:
1. The GPR-2900 front panel measures 7”W x 4”H x 4.5”D. This
compact configuration is designed for panel mounting directly
to any flat vertical surface, wall or bulkhead plate with the
appropriate 6”W x 3”H cut out and four ¼” diameter holes for
insertion of the mounting studs located on the back side of
the front panel.
2. When mounting the analyzer position it approximately 5 feet
off the floor for viewing purposes and allow sufficient room
for access to the terminal connections at the rear of the
enclosure. Note: The proximity of the analyzer to the sample
point and use of optional sample conditioning components have an impact on sample lag time.
3. Position the sensor flow housing along any flat surface. The base of sensor flow housing is fabricated with two 6/32
mounting holes. The oxygen sensor is not position sensitive but it is recommended to orient the sensor flow housing with
the female threaded opening facing the ceiling.
4. Next screw the sensor into sensor flow housing, snug the sensor’s sealing o-ring but do not over tighten or crush it.
5. Register the female plug molded to the cable with the mating male connector attached to the rear of the sensor.
6. Remove the shorting device, normally a formed spring type wire, from the sensor, push the registered mating connectors
together and turn the knurled lock ring on the molded plug until finger tight on the sensor’s connector.
7. Connect the four wires of the cable, following the color coding above the terminal block, at the rear of the analyzer.
8. Attach the flow housing to the mounting position determine above.