8 Fault Analysis/Trouble-shooting
8.1.7
No reference air (can be output as a warning via P395, initiation time 1 hour)
This fault also appears if the reference air is monitored by a flow meter with limit
transducer (e.g. with the efficiency calculation optional extra 657R0895K, see section
4.12.2)
The reference air does not reach the quantity required for flowing around the
reference electrode.
This can result in the falsification of the measurement value.
Possible causes:
•
There is no instrument air (compressed air, reference air pump) at the reference
air connection of the probe.
•
The reference air throttle is not open sufficiently.
•
The signal from the differential pressure sensor has drifted.
Measures:
•
Check electrical and pneumatic connections
•
Reset the reference air quantity, see 6.1.2
Faulty differential pressure sensor? → replace
•
Faulty pressure input card → replace
•
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