7. Fault nding
Table 20
Faults
Fault
LED not lit on page 39
Pressure reading incorrect on page 39
Gauge shows calibraon error on page 39
Gauge shows broken lament on page 40
Fault LED not lit
Cause Incorrect electrical supply voltage. Supply polarity reversed.
Remedy Check the electrical supply and connecons.
Fault Pressure reading incorrect
Cause Vacuum leak
Remedy Do the leak check of the vacuum system.
Cause Tube has dried and requir
es adjustment
Remedy Do the atmosphere and vacuum adjustments.
Cause Tube is contaminated
Remedy Replace the tube.
Cause Gauge is measuring gas with di
er
ent thermal conducvity to Nitrogen or Air.
Remedy Refer to Gas dependency on page 29 for correcon factors.
Cause Adjustment done at an incorrect pressure
Remedy Repeat the adjustment but make sure that the pressure is at atmosphere or
vacuum.
Fault Gauge shows c
alibr
aon error
Cause Adjustment done at an incorrect pressure.
Remedy Repeat the adjustment but make sure that the pressure is at atmosphere or
vacuum.
Cause W
rong type of tube is installed.
Remedy Check that the correct type of tube is installed (M, MP, or LC).
Cause New tube has been installed.
Remedy Refer to R
emote adjustment - APG200 with transistor setpoint [blank] opon on
pag
e 36.
Cause Tube has dried outside permissible limits and can not be adjus
ted.
Remedy Replace the tube.
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D1G0000880_A - Fault nding