Riken Keiki SD-1DOX-AS, Operating Manual

Page: 56 / 69

9 Troubleshooting
- 54 -
<Abnormalities of Readings>
Symptoms Causes Actions
The reading rises (drops)
and it remains so.
Drifting of sensor
output
Perform the zero adjustment (or span adjustment).
Slow leak
A very small amount of the gas to be detected may be
leaking (slow leak). Because ignoring it may cause
dangers, take a remedial measure, i.e., taking actions the
same as those for the gas alarm.
Environmental
changes
Perform the zero adjustment (or span adjustment).
A gas alarm is triggered
despite of no gas leak
and no other
abnormalities at the
detection point.
Disturbance by noise
Turn off and restart the detector.
If such a symptom is observed frequently,
take appropriate measures to eliminate the noise.
Sudden change in
the environment
When the environment (temperature etc.) changes
suddenly, the detector cannot adjust to it and is affected
by it.
In some cases, the detector triggers an indication alarm.
Because the detector cannot be used under sudden and
frequent environmental changes, any preventive actions
to eliminate them should be taken by the user.
Slow response
Clogged dust filter Replace the dust filter.
Bended, clogged,
or leaked suction
tube or exhaust
tube
Fix the defective parts.
Condensation is
formed inside the
suction tube.
Fix the defective parts.
Deteriorated sensor
sensitivity
Replace the sensor with a new one.
Span adjustment
impossible
Improper calibration
gas concentration
Use the proper calibration gas.
Deteriorated sensor
sensitivity
Replace the sensor with a new one.