Troubleshooting
Page
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10.2 PH/Temperature
Resetting Calibration Offset
The pH sensor and pH electrode must be calibrated together to ensure
correct functionality. Calibration data is stored within the pH sensor while the
pH electrode acts as the sensing element.
During a calibration, the calibration data within the sensor is updated/
overwritten in order to compensate for the deterioration of the pH electrode. If
a defective pH electrode has been replaced by a new pH electrode, then the
calibration data must be overwritten. However, the field calibration data stored
in the sensor will not match the new pH electrode – resulting in the new
electrode recording measurements that are offset compared to expectations.
If the offset is too large, the pH sensor will not accept the field calibration
data as valid (Error code indicator: The red LED on the PH sensor will flash
every second). In order to remove the calibration offset, an intermediate buffer
solution must be mixed – refer to example 1 + 2 in the following tables:
