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4.2 pH Calibration Notes
1. A 1-point calibration should be performed at least weekly. In
applications where the sensor junction can become blocked, such as
dairy products, mining slurries etc, a 1-point calibration may have to
be done daily.
2. A full 2-point calibration should be performed at least monthly. Of
course, more frequent calibration will result in greater confidence in
results.
3. All calibration information is retained in memory when the
Aqua-CPA
is switched off, even when the battery is removed.
4. The
Aqua-CPA
displays the value of the pH buffer that it has
attempted to recognise at calibration. Ensure that the buffer value
displayed corresponds to the buffer that you are using.
4.3 pH Calibration Messages
1. If a 1-point calibration has been successfully performed, the
Aqua-CPA
will display the following message, and then display the
asymmetry and slope of the sensor. If the meter has not been
calibrated at two points at this stage, the slope is set to 100.0%.
1 point 6.86
Cal. OK
then:
Asym= 0.10pH
Slope=100.0%
2. If a 1-point calibration has failed, the
Aqua-CPA
will display the
following message, then the failed asymmetry value of the sensor.
1 point 6.86
Cal. Failed
then:
Asym= 1.50pH
3. If a 2-point calibration has been successfully performed, the
Aqua-CPA
will display the following message, and then the
asymmetry and slope of the sensor.
2 point 4.01
Cal. OK
then:
Asym= 0.10pH
Slope= 99.5%
4. If a 2-point calibration has failed, the
Aqua-CPA
will display the
following message, and then the failed slope value of the sensor.
2 point 4.01
Cal. Failed
then:
Slope= 70.0%