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Section 8 Troubleshooting
Error/fault
Possible cause
Remedy
Preventive
measures
Sensor is unusually slow in
responding
The membrane is partially
blocked by pollutants
such as calcium or
oil. Disinfectant is
prevented from reaching
the sensor
Replace membrane cap.
Take steps to improve the
water quality.
Output signal of the sensor
is "0"
The sensor has been
connected to the analyzer
with reverse polarity
Connect the sensor
correctly
The measuring cable is
broken
Replace the measuring
cable
The sensor is faulty
Return to mfr.
Analyzer is faulty
Return to mfr.
Display is blank
Display failure
Main circuit board failure
If main card heartbeat is
flashing replace display. If
main card heartbeat is not
flashing replace card.
Replace display if still blank
with new card installed.
8.1 Specific Troubleshooting Of The Sensor
If the electrode finger has a bright silvery or white appearance, the sensor must be reconditioned by
the manufacturer. Brown-gray colors are normal.
8.11Testing the leak-tightness of the membrane cap
1.
Carefully dry the outside of the membrane cap to be checked.
2.
Prepare the membrane cap for mounting and fill it with electrolyte (2-electrode sensor caps
may use clean water for this test).
3.
If necessary, dry the outside of the membrane cap again.
4.
Slowly and carefully screw the membrane cap onto the sensor shaft.
5.
When screwing the membrane cap on, check if the gel leaks through the membrane.
6.
Check carefully to determine that liquid does not leak through the membrane but that it
escapes at the vent hole designed for this purpose.
If droplets form on the membrane, the membrane is faulty and you must use a new membrane cap.
The formation of a small meniscus is acceptable as the membrane has hydrophilic properties.
If the membrane cap is not leak-proof, you must check if the reference electrode was damaged when
the measuring water and electrolyte were replaced. If the electrode finger has a bright silvery or white
appearance, the measuring cell must be sent to the manufacturer for inspection.
