Fault Finding; Maintenance; Disposal - Grundfos Conex DIA-1 Instrucciones De Instalación Y Funcionamiento

12. Fault finding

Faults during the measurement, see installation and operating instructions for the electrode or
Note
measuring cell.
Fault
1. No display following start-up.
2. pH measurement:
Display permanently indicates
pH approximately 7.
– Measurement of oxidisers:
Display permanently indicates
zero.
– Redox measurement:
Display permanently indicates
approximately 0 mV.
3. Display permanently at
full-scale value.
4. Display with measured value
unsteady.
5. Measurement of oxidisers:
insufficient sensitivity of
measuring cell.
6. pH and redox measurement:
Display with measured value
reacts extremely slowly.
7. pH and redox measurement:
error message during
calibration.
8. Device cannot be set.
9. Faulty control.

13. Maintenance

The device is maintenance-free.
Repairs can only be carried out in the factory by
authorised personnel.
Cause
a) No power supply.
a) Short-circuit in cable between
measuring cell and instrument
amplifier, moisture in connectors.
a) Open circuit in cable between
measuring cell and instrument
amplifier.
a) Interferences on cable from
electrode/measuring cell.
b) pH and redox measurement: air in
sample-water flow.
c) pH and redox measurement:
sample-water flow interrupte.
d) Cable between
electrode/measuring cell and
instrument amplifier broken.
e) Sensor/electrode faulty.
a) Measuring cell contaminated or
passivated by deposits.
a) Electrode aged.
b) Electrode dirty.
a) Wrong buffer solution used.
b) Electrode aged.
c) Electrode dirty.
a) Incorrect code set (device
protected against adjustment).
a) Device is incorrectly
parameterised.

14. Disposal

This product or parts of it must be disposed of in an
environmentally sound way. Use appropriate waste
collection services. If this is not possible, contact the
nearest Grundfos company or service workshop.
Remedy
Connect the power supply.
Check the connection cable
and eliminate short-circuit and
moisture.
Check the connection cable
and reestablish connection.
Check that the display is
properly connected.
Check the sample-water
supply system (pipes, etc.)
and make changes, if
necessary.
Check the sample-water
supply system (pipes, etc.)
and make changes, if
necessary.
Check the connection cable
and reestablish connection.
Replace the sensor/electrode.
Disassemble the measuring
cell, and clean the electrode
surface.
Replace the electrode.
Clean the electrode.
Use the correct buffer
solution.
Replace the electrode.
Clean the electrode.
See section 11.5.7 Code
function.
Check the settings and match
them to the local conditions.
If necessary, reset the device
to the factory settings.
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