Rae MultiRAE PLUS PGM-50, Руководство по эксплуатации и обслуживанию

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TROUBLESHOOTING
8 - 6
4) Battery Type and Bias Display
For some toxic sensors (such as nitric oxide or ammonia
sensor), a bias voltage of a few hundred millivolts is
required for the sensor to function properly. In the
MultiRAE PLUS monitor, the user needs to manually switch
on the bias voltage supply located on the analog PCB (see
Section 7.2 for details). This may alternately be a jumper,
where the jumper position should follow the board marking
– On or Off. For this test to work, a nitric oxide or ammonia
sensor has to be installed in the toxic #1 socket. If the bias
voltage is switched to ON position, the bias reading should
be below 182, otherwise the bias supply may be defective.
The MultiRAE PLUS monitor can be powered by either a
rechargeable Ni-Cd battery pack or an alkaline battery
adapter. This display also shows the type of battery which is
installed inside the monitor.
5) Show x1 and x10 Range of PID Sensor
This diagnostic menu only applies to the monitor which is
equipped with a PID detector option. The PID sensor output
is connected to two amplifiers with two different gains:
Unity gain and gain of ten. Raw outputs of both amplifiers
are displayed. When zero gas is applied, both amplifier
output should be between 200 to 500. When a VOC gas is
applied, both amplifier output should increase and the
amount of increase for the unity gain (x1) amplifier should
be about 1/10 of the increase for the gain of ten (x10)
amplifier. If the increase does not agree with expected
value, then the gain switch of the amplifier may be defective.
6) Adjust LCD Contrast