wtw PROTOC 200, Operating Manual

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What to do if... PROTOC 200
7 - 52
7 What to do if...
7.1 The display responds slowly or not at all to the calibra-
tion solution or sample
7.2 Calibration and/or zeroing does not function
Cause Actions
Reagent solution
– The reagent solution is too old
or too weak
– Prepare and use a fresh
reagent solution
Tubing system
– The pump tubes are damaged
or blocked so that the solution
cannot be pumped correctly
– Check the tubes and replace
them if necessary
Gas supply
– Leakage in the gas supply – Block the IR detector output
and observe whether the
liquid in the U-tube is
displaced all the way to the
bottom.
– If it is not completely
displaced, there is a leakage
in the gas supply. Repair the
leakage.
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
– During the last calibration/
zeroing, the measurement had
not yet completely stabilized
– Wait for the stabilization
period to elapse when
zeroing/calibrating
– Tube or solenoid is blocked – Remove blockage
AL sensor flashes