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M U L T I G A S D E T E C T I O N
9.
TROUBLESHOOTING
9.1 SENSOR NOT RECOGNISED
When “XXX” is shown in sensor position on the display, it indicates a missing or defective
sensor. If it is a LEL sensor, the sensor may need to be zeroed using the procedure in
Section 9.2 “LEL FAIL” Message
.
9.2 “LEL FAIL” MESSAGE
When this message comes up after start-up, you can reset the zero base of the LEL
sensor as follows:
1)
Turn on the instrument.
2)
When the instrument displays “TESTING” and “PLEASE WAIT” and starts to count
down from 30, depress and hold the MODE button for about 5 seconds, until
display reads “SEL LEL GAS TYPE”.
3)
Open the instrument by removing the 4 screws from the rear cover of the case. Do
not unplug the wires from the rear cover to the sensor board. Observe the
potentiometer (trimpot) for the LEL zero. It is located beside the pump and is the only
potentiometer (trimpot) in the instrument.
4)
Set digital voltmeter to the DC voltage range, black lead to test point 12 (analog
ground) and the red lead to test point 10. These test points are on the same sensor
board as the pump, trimpot and sensors.
5)
Adjust the potentiometer (trimpot) for a reading of 0.500 volts (+/- 0.005 volts).
6)
Reinstall cover.
7)
Exit supervisory mode.
9.3 LOW FLOW ALARM WHEN SAMPLING HOSE ATTACHED
Low flow alarm is activated when a sampling hose is connected.
1)
Clean the stone filter at end of sampling hose.
2)
Make sure that the sampling hose, or water-trap is not “kinked” or blocked with debris.
3)
Remove sampling hose, clean or replace inlet filter.
9.
TROUBLESHOOTING
9.4 “CALIBRATION FAIL” MESSAGE
Check for proper gas concentration and expiration date.
9.5 INSTRUMENT WILL NOT TURN ON
Charge instrument or install fresh alkaline batteries.
9.6 INSTRUMENT IS IN DIFFUSION MODE BUT PUMP COMES ON
WHEN CALIBRATING
This is normal instrument behavior. The pump will automatically turn off when calibration
is complete.
