Two test containers with a buffer solution are required for calibration. The pH value of the
buffer solutions should be at least 2 ph values apart. The sensor should be rinsed thor‐
oughly with water when changing the buffer solution.
1.
Select Calibration menu
2. Immerse sensor in test container 1 with buffer solution (e.g. pH 7)
3. Move the sensor gently until the pH value displayed no longer changes
4.
Then press
ð
Calibration is running
A buffer value is suggested once the waiting time has expired.
5.
If necessary adjust the pH value displayed using keys , and to the actual
value of the buffer solution in test container 1
6.
Then press
7. Remove the sensor, rinse thoroughly in water and then dry with a cloth (pad dry,
don't rub!)
8. Immerse sensor in test container 2 with buffer solution (e.g. pH 4)
9. Move the sensor gently until the pH value displayed no longer changes
10.
Then press
ð
Calibration is running
A buffer value is suggested once the waiting time has expired.
11.
If necessary adjust the pH value displayed using keys , and to the actual
value of the buffer solution in test container 2
12.
Then press
ð
The settings recorded will be displayed.
13.
If the calibration result is correct, confirm with
ð
The new calibration is now applied.
Should the result of the calibration lie outside of the specified error limits, an error mes‐
sage will appear, see
Ä Chapter 8.5.3 ‘Calibration of pH Sensors. Description of the
Error Messages ’ on page 91
. In this case the current calibration will not be applied.
Measured Variables and Operating Menus for Potentiometric Sensors
89