Riken Keiki GD-84D-EX Series, Operating Manual

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10. Troubleshooting 10-2 Reading abnormalities
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10-2 Reading abnormalities
Symptom Cause Corrective action
The reading rises (or
drops) and remains
unchanged.
Sensor drift Perform zero calibration or air calibration.
Presence of
interference gases
It is difficult to completely eliminate the effects of
interference gases such as solvents. Contact Riken
Keiki for information on countermeasures, such as
interference gas removal filters.
Slow leakage
They may be a very small leakage (slow leakage) of
the detection target gas. Leaving this unresolved may
lead to hazardous conditions. Take the same action
as for gas alarms.
Environmental
fluctuations
Perform zero calibration or air calibration.
Galvanic cell types in particular are susceptible to the
effects of atmospheric pressure. Zero calibration and
air calibration must be performed.
A gas alarm is issued
despite the absence of a
gas leak or other
abnormalities at the
detection point.
Presence of
interference gases
It is difficult to completely eliminate the effects of
interference gases such as solvents. Contact Riken
Keiki for information on countermeasures, such as
interference gas removal filters.
Effects of noise
Turn the power OFF and restart.
If similar symptoms recur frequently, take appropriate
measures to address the noise source.
Sudden environmental
changes
Reading alarms may be triggered by sudden changes
in ambient conditions such as temperature.
The product cannot be used if ambient conditions
fluctuate rapidly and often. Take appropriate action to
prevent such changes.
Slow response
Clogged dust filter Replace the dust filter.
Bent or blocked inlet
or outlet tube
Fix the problem.
There is condensation
inside the inlet tube.
Fix the problem.
The sensor sensitivity
has degraded.
Replace with a new sensor.
Span adjustment is not
possible.
The calibration gas
concentration is
inappropriate.
Prepare the correct calibration gas.
The sensor sensitivity
has degraded.
Replace with a new sensor.