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6.2 Calibration Notes
1.
A 1-point calibration should be performed at least weekly. In applications
where the electrode 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
WP-81T
is
switched off, even when the battery is removed. This information can be
recalled or printed later using the GLP function (see section 8).
4.
The
WP-81T
displays the value of the pH buffer to which it will attempt to
calibrate. Ensure that the buffer value displayed corresponds to the buffer that
you are using.
6.3 Calibration Messages
1.
If a 1-point calibration has been successfully performed, the
WP-81T
will
display the following message, and the asymmetry of the electrode.
eg:
1 Point Cal.OK
Asy= 0.10pH
2.
If a 1-point calibration has failed, the
WP-81T
will display the following
message, and the failed asymmetry value of the electrode.
eg:
1 Point Cal.Fail
or:
1 Point Cal.Fail
Asy= 1.50 Hi
Asy=-1.50 Lo
3.
If a 2-point calibration has been successfully performed, the
WP-81T
will
display the following message, and the asymmetry and slope of the electrode.
eg:
2 Point Cal.OK
then:
2 Point Cal.OK
Asy= 0.10pH
Slope=100.0%
4.
If a 2-point calibration has failed, the
WP-81T
will display the following
message, and the failed slope value of the electrode.
eg:
2 Point Cal.Fail
or:
2 Point Cal.Fail
Slope=130.0% Hi
Slope= 70.0% Lo