VWR 662-2283, Руководство по эксплуатации

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PH20 Maintenance | 7
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9. Place the electrode in the second buffer solution. The product recognises whether
it is a
PK 4
or
PK 10
buffer solution automatically.
10. Enter the temperature of the buffer solution by pressing the Up key and Down key
and confirm the entry by pressing the
Function key
again.
11. Then, rinse the electrode again with distilled or deionised water.
Outcome of an action 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 dis-
play 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.
appears in the display. See Error and system messages [
}
p. 27] . Confirm the error
message pressing the
Function key
. The product restarts and the standard value for
the zero point and gradient are restored.
7.3.1.4 Manual 1-point pH calibration
Description 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.
Prerequisite – An arbitrary buffer solution is available.
Instruction 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 key
and
Down key
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 key
and
Down key
and confirm the entry by pressing the Function key again for 2 seconds.
9. Then, rinse the electrode again with distilled or deionised water.
Outcome of an action
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 dis-
play 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.
appears in the display. See Error and system messages [
}
p. 27] .
7.3.1.5 Manual 2-point pH calibration
Description
The following steps describe how to perform a 2-point pH calibration.
Prerequisite – 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.
Instruction
1. Press the
Function key
for 2 seconds to open the
Configuration
menu.