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If the measured values (pH + temperature!) are in a stable condition, reconfirm by pressing
(
ON/OFF
).
> You will be prompted to enter a nominal value (temperature-corrected buffer value!).
Via (
INFO
) or (
CAL
) you select the position to change.
Via (
CONF +1
) or (
LOG -1
) you change the position.
(
ON/OFF
) confirms and saves your setting.
(
MEAS
) terminates the entry dialog without transferring the value.
> You will be prompted to immerse the sensor into the
second calibration medium
.
Perform the same steps as with the first calibration solution
8.4.2.4 Three point calibration
> You will be prompted to immerse the sensor into the
first calibration medium
(ambient air).
Confirm this dialog with (
ON/OFF
). The currently measured values will be displayed.
If the measured values (pH + temperature!) are in a stable condition, reconfirm by pressing
(
ON/OFF
).
> You will be prompted to enter a nominal value (temperature-corrected buffer value!).
Via (
INFO
) or (
CAL
) you select the position to change.
Via (
CONF +1
) or (
LOG -1
) you change the position.
(
ON/OFF
) confirms and saves your setting.
(
MEAS
) terminates the entry dialog without transferring the value.
> You will be prompted to immerse the sensor into the
second calibration medium
.
Perform the same steps as with the first calibration solution
> You will be prompted to immerse the sensor into the
third calibration medium
.
Perform the same steps as with the first calibration solution
8.4.2.5 Automatic calibration (Two and Three point)
The automatic calibration of the pH measurement is a two point calibration and requires the knowledge, which
buffer solutions you would like to use for the calibration.
The PTM40 offers the following buffer sets for the calibration:
NBS standard buffer solution as per DIN 19266:
pH value at 25 °C 1.68 / 4.01 / 6.86 / 9.18 / 12.45
Technical buffer solution as per DIN 19267:
pH value at 25 °C 1.09 / 3.06 / 4.65 / 6.79 / 9.23
Merck buffering solution:
pH value at 20 °C 4.00 / 7.00 / 9.00
Laboratory buffer solution:
pH value at 25 °C 2.00 / 4.01 / 6.98 / 8.95 / 11.88
> Select the buffer set you would like to use for the calibration.
You will be prompted to immerse the sensor into the
first calibration solution
.
Confirm this dialog with (
ON/OFF
). The currently measured values will be displayed.
If the measured values (pH + temperature!) are in a stable condition, reconfirm by pressing
(
ON/OFF
). The found buffer will be displayed, reconfirm with (
ON/OFF
).
Immerse the sensor into the
second calibration solution
.
Perform the same steps as with the first calibration solution.
Immerse the sensor into the
third calibration solution
. (automatically three point calibration)
Perform the same steps as with the first calibration solution.
This completes the calibration process. The new calibration value will be saved in the device.
