wtw PROTOC 200, Operating Manual

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PROTOC 200 What to do if...
7 - 53
Note
Manually carry out zeroing and calibration after troubleshooting. Press
the ALARM key to shut off the sensor alarm.
7.3 Unstable readings
– Leakage in gas supply – See section 7.1 T
HE DISPLAY
RESPONDS SLOWLY OR NOT
AT ALL TO THE CALIBRATION
SOLUTION OR SAMPLE
Cause Actions
Calibration/zeroing deviates from
the nominal values by more than
the specified hysteresis.
– Carrier gas flow fluctuates – Use the appropriate
pressure regulator and
adjust it correctly
– The displacement in the U-tube
is not constant
– Ensure that the flow of liquid
through the system is steady
– Check the gas outlet section
and the sparge vessel for a
steady flow of sample
through the system
– Correct the positions of the
PTFE tubes if necessary
– Leakage in gas supply – See section 7.1 T
HE DISPLAY
RESPONDS SLOWLY OR NOT
AT ALL TO THE CALIBRATION
SOLUTION OR SAMPLE
Cause Actions
AL sensor is
displayed