6.1 Calibration
CAUTION!
–
The gradient must be calibrated after
every manipulation on the sensor
(e.g. electrolyte replacement, emery
treatment, etc)!
–
The gradient has to be re-calibrated at
regular intervals to ensure the perfect
operation of the sensor ! If there are no
other regulations then the sensor only
needs to be calibrated every 3-4 weeks
for use in drinking water and swimming
pool water.
–
Avoid air bubbles in the sample water!
Air bubbles, which adhere to the
sensor can result in too low a reading
and thus lead to dangerous over-
metering.
–
Please note the pertinent national
guidelines for calibration intervals!
Prerequisites
–
The sensor is ready (wait for run-in
time).
–
Constant flow rate at the flow gauge
–
Constant temperature of the sample
water
–
Each time after either installing or
removing the sensor, wait until the run-
in time expires and a constant reading
is achieved, but at least 15 minutes to
avoid drifts caused by the temperature
equalisation.
–
No concentration fluctuations of the
feed chemical in the sample water
–
Constant pH value within the permis‐
sible range
–
The sample must be taken at the place
the sensor is installed
Zero point calibration
If the sensor is operated at a control device from
ProMinent then zero point calibration is normally
not necessary. Zero point calibration is recom‐
mended if you want to use the sensor in the lower
limit of the measuring range.
1.
Place the sensor in a vessel with clean
water free of chlorine and oxidising agent
(e.g. mineral water without gas).
2.
Stir with the sensor until the reading on
the control device remains steady for at
least 5 minutes
3.
Calibrate the control device to zero in
accordance with its operating manual
4.
Refit the sensor into the flow gauge
(DGM; DLG III).
Commissioning
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