Hach AN-ISE sc, Addendum To The Operator Manual

Page: 21 / 152

English 21
Troubleshooting
6.3 Troubleshooting
6.3.1 Troubleshooting during operation
Symptom Possible cause Corrective measures
Incorrect
measurement values
Calibration too old; calibration was not suitable for
the particular application; large change in the waste
water matrix Perform a suitable calibration.
Refer to 4.6 Calibration/matrix correction,
Page 25
Severely contaminated membranes and/or
reference electrode
Clean the sensor cartridge using a brush
and/or rinse the sensor cartridge with clean
water (without cleaning agents), and wipe the
sensor cartridge carefully with a soft, clean
cloth.
Clean all components (membranes/reference
electrode/temperature sensor).
Install the cleaning unit
Increase the cleaning interval
Sensor membrane damaged
Check the sensor installation/
replace the sensor cartridge
Reference element damaged
NO
3
mV is out of range!
1,3
Replace the sensor cartridge
Cl- mV is out of range!
1,3
Reference electrode 1 mV is out of range!
Reference electrode 2 mV is out of range!
Temperature is out of range!
Replace the sensor cartridge/check the
waste water temperature
The cartridge has expired. Replace the sensor cartridge
Moisture at the contacts of the sensor cartridge
Dry the contact with a cloth or paper
Check the black gasket for damage and
make sure it is in the correct position.
Screw the 4 socket head screws tight.
Incorrect
measurement values
Moisture inside the measurement probe/faulty
sensor electronics
Check the sensor electronics by using the test
cartridge (
section 7.2, page 39 ).
1 Select Sensor menu > Maintenance > Service >
Cartridge test> Cartridge test. Press Enter
2 If all channels are confirmed with OK, the
sensor electronics are operational:
Test cartridge
Ok
Enter
If the test cartridge data is not within this
range and/or if the test cartridge check is not
successful, contact the service department.
Potassium concentrations too high (e.g.: >700 mg/L
in the case of small ammonium concentrations) or
chloride concentrations too high (e.g.: >1000 mg/L
in the case of small nitrate concentrations)
Switch off potassium/chloride compensation
(in the configuration menu - then potentially
enter a fixed value for potassium/chloride)
Unstable
measurement values
Air bubbles, depth of immersion
Check the sensor installation
Check the cleaning unit configuration
Moisture at the contacts of the sensor cartridge
Dry the contacts with a cloth or paper.
Check the black gasket for damage and
make sure it is in the correct position.
Screw the 4 socket head screws tight
Sensor membrane damaged
Check the sensor installation/
replace the sensor cartridge
Reference element damaged