Manual

9 Troubleshooting
- 73 - GD-70D
Symptom/Display FAULT Causes Actions
The rated voltage is not
supplied to the detector.
Check the power supply, and supply the rated
voltage.
System
Abnormalities
E-9 SYSTEM
●
Abnormalities of ROM, RAM,
or EEPROM inside of the
detector
Please contact our sales department.
<Abnormalities of Readings>
Symptoms Causes Actions
Drifting sensor Perform the zero adjustment (AIR adjustment).
Presence of interference gas
Disturbances by interference gases, such as
solvents, cannot be eliminated completely. For
information on actions, such as removal filter,
please contact our sales department.
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.
The reading rises (drops) and it
remains so.
Environmental changes Perform the zero adjustment (AIR adjustment).
In particular, the galvanic cell type is affected by
the air pressure.
Presence of interference gas
Disturbances by interference gases, such as
solvents, cannot be eliminated completely. For
information on actions, such as removal filter,
please contact our sales department.
Disturbance by noise Turn off and restart the detector.
If such a symptom is observed frequently, take
appropriate measures to eliminate the noise.
A gas alarm is triggered despite
of no gas leak and no other
abnormalities at the detection
point.
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,
you must take any preventive actions to eliminate
them.
Clogged dust filter Replace the dust filter.
Bended or clogged suction
tube or exhaust tube
Fix the defective parts.
Condensation is formed
inside the suction tube.
Fix the defective parts.
Slow Response
Deteriorated sensor
sensitivity
Replace the sensor unit with a new one.
Improper calibration gas
concentration
Use the proper calibration gas.
Sensitivity Calibration Impossible
Deteriorated sensor
sensitivity
Replace the sensor unit with a new one.