Analytical Industries GPR-2500 Series Oxygen Transmitter User Manual
Page 9

9
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 particulates, liquids or condensation collect on the sensor that could block the diffusion
of oxygen into the sensor.
¾ If the transmitter 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.