Fault Finding - Grundfos DID Montage- Und Betriebsanleitung

11. Fault finding

See also the manual "Sensors" supplied with the sensor. Find the manual "Sensors for DID" on Grundfos Product Center: (http://
net.grundfos.com/Appl/ccmsservices/public/literature/filedata/Grundfosliterature-6119622.pdf).
Fault
1. No water flow
2. Water is running out of the
sampling point.
3. The power supply LED is off.
4. The displayed system time is
not correct or is not updated
every second.
5. Error messages or error
symbols are displayed.
6. Hoses or connections are
leaking.
7. The flow detector shows no
flow.
8. Water is not visible in the
hoses.
9. Water is not visible in the
hoses. Air comes out of the
flow restrictor.
10. The parameter readings are
fluctuating.
11. The parameter readings are
not plausible.
12. The readings are not within
the specified and calibrated
measuring range.
Cause
a) The inlet valve is closed.
b) The inlet strainer is blocked
c) The flow detector or the flow
restrictor is blocked.
a) The sampling point is not closed
correctly.
a) No power supply.
a) The internal clock is not adjusted.
a) The sensor communicates an
error.
a) The fittings are not tight.
a) The inlet valve is closed.
b) The inlet strainer is blocked.
a) The inlet valve is closed.
b) The inlet strainer is blocked.
a) The pressure on the inlet is too
high.
a) The measuring electrode is
contaminated or faulty.
b) The inlet strainer is blocked.
c) Air bubbles are in the flow cell.
a) The measuring electrode is
contaminated or faulty.
b) The inlet strainer is blocked.
c) Air bubbles are in the flow cell.
a) The sensor or the DID was
powered-on very recently.
b) The concentration of the measured
substance is to high.
Remedy
Open the inlet valve completely.
Clean the filter of the inlet strainer.
Clean the flow detector or the flow restrictor, or replace the
complete component.
Close the outlet fitting of the sampling point.
Connect to the power supply.
Adjust the clock in the "Setup" menu.
Restart the CU 382 control unit.
In the menu "Parameter settings", select "Monitor" and
check the sensor status. See also the manual "Sensors" for
status information.
Tighten the fittings carefully. Do not use force.
Open the inlet valve.
Clean the inlet strainer.
Open the inlet valve.
Clean the inlet strainer.
Reduce the pressure on the inlet.
Exchange the electrolyte or the membrane cap. See the
manual "Sensors" for more information.
Clean the inlet strainer.
Reduce the pressure on the inlet.
Exchange the electrolyte or the membrane cap. See the
manual "Sensors" for more information.
Clean the inlet strainer.
Reduce the pressure on the inlet.
It takes up to an hour until a sensor provides correct
values.
Change to a sensor with a wider measurement range.
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