Fault Finding - Grundfos AQC-D6 Montage- Und Betriebsanleitung

11. Fault finding

Observe the Oxiperm Pro installation and operating instructions.
Fault
1. Display frozen.
2. Measured value
fluctuating shortly after
calibration.
3. Severely fluctuating
measured value.
4. Measured value too high
or too low.
Measuring module
5. Either no or not enough
sample water flowing
through measuring
module.
6. Not enough sample
water flowing through
flow fitting / AQC-D6
measuring cell.
Cause
a) Cable break.
b) Calibration fault.
c) Incorrect analysis values used for calibration.
a) Measuring cell not allowed to run in correctly
before calibration.
a) Cable and/or connectors corroded.
a) Air bubbles in electrolyte.
b) Not enough electrolyte in electrolyte chamber.
c) Severe change in temperature of sample water.
d) Deposits on electrode finger.
e) Air bubbles in front of measurement opening
(sample water side).
a) Main water line closed off.
b) No sample water present.
c) Isolating valve on measuring module input and/or
output closed.
d) Circulating pump not functioning.
e) Overheating protection of circulating pump has
been triggered.
f) Circulating pump defective.
a) Circulating pump not running. See above.
b) Main current of the measuring module not
sufficiently throttled.
Remedy
Rectify the cable break.
Repeat the calibration.
Repeat the calibration with correct values.
Allow the cell to run in for one hour before
calibration.
Replace the cable(s)/connector(s), and replace
the electrode, if necessary.
Unscrew the electrolyte chamber, and remove
any air bubbles by carefully tapping the
electrolyte chamber.
Unscrew the electrolyte chamber, fill up with
electrolyte and recalibrate.
Recalibrate.
Unscrew the electrolyte chamber. Rinse the
electrode finger, dry it with a dry paper towel,
and carefully clean just the tip of the electrode
finger with the special emery paper, then
recalibrate.
Check the water supply line.
Open the main water line.
Check the sample water extraction point and
supply line.
Open the isolating valve.
Switch on the circulating pump.
Allow the circulating pump to cool off, then
switch it back on.
Replace the circulating pump.
See above.
Throttle the main current more heavily using the
throttle valve until the sample water flow rate is
OK.
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