8.5.2 Calibration of pH Sensors. Description of the Setting Ranges
Setting Possible values
Starting
value
Increment Lower value Upper value Remarks
Calibration
temperature
Reading 0.1 ℃ 0 °C 100 ℃
Buffer
values
Reading
(whole digit
rounded up)
0.01 pH -1.45 pH 15.45 pH Error mes‐
sage if the
two buffers
lie too close
to each
other (<2 pH
values)
8.5.3 Calibration of pH Sensors. Description of the Error Messages
Error message Condition Effect
Buffer gap too small ∆buffer <2 pH During the calibration process: recalibrate
buffer 2!
Back to the permanent display
pH zero point low < -60 mV Basic load metering Note: old zero point and
gradient remain
pH zero point high > +60 mV Basic load metering Note: old zero point and
gradient remain
pH gradient low < 40 mV/pH Basic load metering Note: old zero point and
gradient remain
pH gradient high > 65mV/pH Basic load metering Note: old zero point and
gradient remain
pH reading
unsteady
Note: old zero point and
gradient remain
°C reading
unsteady
Note: old zero point and
gradient remain
The following applies to all error messages: eliminate the source of the error and
repeat calibration.
Measured Variables and Operating Menus for Potentiometric Sensors
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