Operation
13
4.1.1. pH calibration
Calibration of the pH probe is required regularly (at least after 20
measurements) and with each new probe.
1. Immerse a clean pH electrode at first in buffer solution pH 7 and stir
it slightly.
2. Select MODE>CALIBRATION.
3. Start calibration with SELECT. The display
shows “please wait…”.
4. The info line 1 indicates the buffer solution pH 7. The calibration
process is displayed as a progress bar.
5. After the pH 7 calibration is finished, the display shows "now change
to pH 4 and then start with OK".
6. Remove and clean the pH electrode. Immerse the electrode in the
buffer solution pH 4 and stir it slightly. Then start the calibration with
OK. Display
shows “please wait…”.
7. The info line 1 indicates the buffer solution pH 4. The calibration
process is displayed as a progress bar.
8. After the pH 4 calibration is finished, the display shows "pH10
calibration? no = MODE yes = OK".
9. If a 3-point calibration is desired, remove and clean the electrode,
immerse it in the buffer solution pH10 and stir it slightly. Then start
the calibration with OK. The display shows
“please wait…”.
10. The info line 1 indicates the buffer solution pH 10. The calibration
process is displayed as a progress bar.
11. Calibration values are stored.
12. Calibration can be repeated as often as required.
False calibration sequence, false buffer solutions, defect of the pH
electrode or other failure will be displayed with "Check sensor/medium /
confirm with OK ".
The slope of the pH electrode [mV/pH] and the current sensor voltage
[mV] can be called up any time under MODE>pH-SENSOR STATUS.