G 1501
Operation and maintenance | 6
B-H86.0.12.DB2-2.1
21 / 37
6.3.1.4
Manual 1-point calibration
The following steps describe how to perform a 1-point pH calibration.
NOTE
A 1-point calibration is only advantageous if measurement takes place in a narrow
range around the calibration point. A reliable electrode evaluation is not possible in
this case. We recommend conducting a 2-point calibration, because a 1-point calibra-
tion only entails a shift of the zero point.
–
An arbitrary buffer solution is available.
1.
Press the
Function key
for 2 seconds to open the
Configuration
menu.
2.
(ONF
appears in the display. Release the Function key.
3.
The parameter
SET.T
appears if the temperature sensor is not plugged in. If the
temperature sensor is plugged in, you jump to the next point.
4.
Enter the temperature of the buffer solution by pressing the
Up button
and
Down
button
and confirm the entry by pressing the
Function key
again.
5.
The
PK.OF
parameter appears in the display.
6.
Place the electrode in the buffer solution.
7.
Wait until the display value is stable.
8.
Adjust the value corresponding to the buffer solution with the
Up button
and
Down
button
and confirm the entry by pressing the
Function key
again for 2 seconds.
9.
Then, rinse the electrode again with distilled or deionised water.
After successful completion of the calibration the assessment of the electrode condi-
tion is displayed briefly in percent. Then, the current measurement is shown in the
display again. A low value can be the result of the age of the electrode, contaminated
or old buffer solutions or impurities on the BNC connector.
If the calibration is not completed successfully an error message is displayed.
(AL ERR.
6.3.1.5
Manual 2-point calibration
The following steps describe how to perform a 2-point pH calibration.
–
A buffer solution with a value between pH 6.75 and pH 7.25 is available.
–
A second buffer solution with a value below pH 6 and above pH 8 is available.
1.
Press the
Function key
for 2 seconds to open the
Configuration
menu.
2.
(ONF
appears in the display. Release the
Function key
.
3.
The parameter
SET.T
appears if the temperature sensor is not plugged in. If the
temperature sensor is plugged in, you jump to the next point.
4.
Enter the temperature of the buffer solution by pressing the
Up button
and
Down
button
and confirm the entry by pressing the
Function key
again.
5.
The
PK.OF
parameter appears in the display.
6.
Place the electrode in the buffer solution with a value between pH 6.75 and pH
7.25.
7.
Wait until the display value is stable.
Description
Prerequisite
Instruction
Outcome of an action
Description
Prerequisite
Instruction
