Grundfos Conex DIA-2Q Bedienungsanleitung Seite 47

The pH calibration is carried out as a two-point
calibration.
pH
cal. meas. value
cal result
cal. cycle
1. Press [Cal] to switch to the calibration function.
Select the line "pH", and press [OK] to switch to
the "pH" calibration menu.
2. Select "cal. meas. value", and press [OK] to
switch to the corresponding menu.
Selecting buffer types and buffer values, reading
in buffer values and calibrating
Three optional buffer types are available:
• GRUNDFOS: buffer values pH 4.01, 7.00, 9.18.
• DIN/NIST: buffer values pH 4.01, 6.86, 9.18.
• "others": Lower and upper buffer values can be
freely adjusted (difference at least 1 pH) within
the configured pH value measuring range
("setup" menu).
buffer
GRUNDFOS
DIN/NIST
others
1. Select a buffer type using the [Up] and [Down]
buttons.
2. Press [OK] to jump to the "temperature" menu
automatically.
3. Enter the temperature of the buffer solution used.
4. Press [OK] to jump to the "buffer value 1" menu
automatically.
buffer value 1
4.01 pH
7.00 pH
9.18 pH
5. Select one of the three optional buffer values
offered for the buffer solutions GRUNDFOS or
DIN/NIST.
6. Fill buffer 1 from the storage bottle into a clean
calibration cup.
7. Dip the electrode into the buffer solution.
8. Press [OK] to start the automatic reading function
(reading in of measured signal) and the
calibration.
– The display shows the message "please wait"
during the calibration.
– The automatic reading function during pH
calibration has the effect that the correct
electrode signal for the buffer value is read
only when the measuring signal remains stable
during a defined interval.
9. Dispose of the first buffer solution (i.e. do not
return it to the storage bottle!), and rinse the
electrode with water.
10. Press [OK] to jump to the "buffer value 2" menu
automatically.
buffer value 2
7.00 pH
9.18 pH
It is only possible to choose between the
two remaining buffer values.
1. Fill buffer solution 2 from the respective storage
bottle into a clean calibration cup.
2. Dip the electrode into the second buffer solution.
3. Press [OK] to start the automatic reading function
and the calibration.
4. After that, dispose of the buffer solution and rinse
the electrode with water.
CALDATA pH
slope
- 60.17 mV/pH
asym. pot.
19 mV
Immediately after the calibration, its result is
displayed automatically:
• sensor slope in mV/pH
• asymmetry potential of the electrode in mV.
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