Burkert 8232 - Changing the Membrane Cap; Checking the Measuring Signal During Operation

→ Fill the membrane cap with the electrolyte as described in chap. 7.3.
→ For a sensor with an internal holder, fill the internal holder with
the electrolyte as described in chap. 7.3.
→ Make sure the tightness of the membrane cap. See chap. 9.3.1.
→ Calibrate the slope (see the Operating Instructions of the con-
troller the sensor is connected to).
→ If the slope calibration is still not possible because of unstable
or too low values, change the membrane cap and the internal
holder. See chap. 9.3.3.
9.3.3. Changing the membrane cap
Change the membrane cap:
• once a year;
• if the slope calibration is not possible due to unstable or
too low values displayed.
→ Unscrew the membrane cap.
→ Pour the old electrolyte out from the membrane cap.
→ Clean the working electrode with a clean and dry paper towel.
→ For a sensor without internal holder, take a new membrane cap
and fill it with the electrolyte. See chap. 7.3.
→ For a sensor with an internal holder, take a new membrane cap
and a new internal holder and fill them with the electrolyte. See
chap. 7.3.
→ Make sure the membrane cap is tight. See chap. 9.3.1.
→ Calibrate the slope (see the Operating Instructions of the
remote controller type 8619 the sensor is connected to).
→ If the slope calibration is still not possible because of unstable
or too low values, make sure the membrane cap and the internal
holder.
9.3.4. Checking the measuring signal
during operation
→ If the measuring water contains chlorine:
1. Take a sample of the measuring water.
2. Measure the chlorine concentration of the sample with the
DPD-1 method.
3. Compare the obtained value with the value measured by the
sensor.
4. If the obtained value approaches the value measured by the
sensor, the sensor is working correctly. If the two values are dif-
ferent, perform a slope calibration. See chap. 8.
→ If the measuring water is free of chlorine, do an external cali-
bration with the external calibration device:
1. Take a sample of 250 ml of the measuring water and pour it into
a beaker with a magnetic stirrer bar inside.
2. Add 0,2 mg/l of chlorine to the sample and place the beaker on
the magnetic stirrer.
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Maintenance and troubleshooting
Type 8232
english