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3.2 Calibration Notes
1. A Zero calibration should be performed at least monthly. In low
conductivity applications (where a zero error is particularly significant)
a zero calibration may have to be done weekly.
2. A Standard calibration should be performed at least weekly. 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.
3.3 Calibration Messages
1. If a Zero calibration has been successfully performed, the
Aqua-CPA
will display zero value of the sensor. For example…
Cal. OK
Zero= 0.01uS
2. If a Standard calibration has been successfully performed, the
Aqua-CPA
will display the calculated k factor of the sensor. For
example…
Cal. OK
k=1.10
3. If a Standard calibration has failed, the
Aqua-CPA
will display the
calculated k factor of the sensor following message, and then the
failed span value of the sensor.
Cal. Failed
k=0.60
4. The
Aqua-CPA
will display the following message if it fails to
recognise the calibration standard. This can occur if the calibration
standard is incorrect, or if the sensor response is incorrect by a very
large margin.
Unknown Std.
Not ReCal.
Note that the decimal point is replaced by a “
∗
“ when a Standard
calibration fails.