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Symptom:
The display does not blink at 2.7
×
10
+3
Pa when atmospheric pressure is being measured.
Possible cause
Corrective action
• The type of sensor head differs from the
specified one.
1) Change the sensor head with the specified type.
Or re-adjust and re-calibrate the one in use.
• Gas under measurement is not nitrogen
or air.
1) Normal
• Gas under measurement is nitrogen or
air, but contains much moisture and oil.
1) Normal
• The sensor head is contaminated or the
sensor head filament has worn out.
1) Replace the sensor head.
• Air temperature at the location where
the sensor head or controller is installed
is high. (This gauge has been adjusted
at 25°C.)
1) Change the place of installation. (Install in a clean,
well ventilated place not blown with draft.)
Symptom:
Pressure display does not show a constant value.
Possible cause
Corrective action
• The pressure is changing.
1) Normal
• The type of sensor head differs from the
specified one.
1) Change it with the specified one. Or re-adjust
and re-calibrated the one currently in use.
• The sensor head is contaminated or the
sensor head filament has worn out.
1) Replace the sensor head.
• Leak in the sensor head or area where it
is installed.
1) If there is a leak in the sensor head, replace it.
If there is a leak elsewhere, stop it.
• Poor contact of the sensor head cable or
increased resistance of wire rod due to
corrosion or other.
1) Check the sensor head cable referring to Fig. 13-6
"Sensor head connection diagram".
