The sensor stability information displayed
during calibration,
[acceptable]
,
[good]
and
[very good]
, indicates to what extent the sensor
signal fluctuates during calibration. At the start
of calibration, the waiting time for stabilisation
of the measured value is 30 seconds; during
this waiting time,
[Please wait!]
flashes in the
display. You cannot continue with calibration
during this waiting time.
If the pH sensor is cold, e.g. < 10 °C, then the
pH sensor responds slowly and you have to
wait a few minutes until the sensor signal has
stabilised.
The controller has no waiting time limit. You will
see the actual [sensor voltage] in mV and can
identify high fluctuations and assign influences
to them, such as the movement of the sensor
cable.
Calibration is impossible if the sensor signal is
very unsteady and the sensor signal is dis‐
rupted by external influences, or if the sensor
cable has a cable break or the coaxial cable is
damp. Rectify any fault or cable break.
You can only continue with calibration once the
signal bar has reached the
[acceptable]
range
and remains there or moves towards
[good]
or
[very good]
. Changes to the signal within the
ranges
[acceptable]
,
[good]
and
[very good]
are
permitted.
The signal fluctuation width within the ranges is
specified as follows:
n first 30 seconds wait time, then evaluation
of the sensor signal
– Acceptable: 0.5 mV/30s
– Good: 0.3 mV/30s
– Very good: 0.1mV/30s
CAL pH
Asymmetry
Buffer 2:
A1019
Zero point
Slope
% Slope
Accept with <CAL>
Buffer 1:
Calibr.param. for 25 °C
Fig. 35: Display of the calibration result
CAL pH
Sensor quality
A1481
Slope in mV/pH
acceptable
good
good
Asymmetry in mV
Fig. 36: Displayed after the key has been
pressed
10.1.1 Selecting the Calibration
Process for pH
To calibrate the controller there are three avail‐
able calibration processes:
n 2-point
n Sample (1-point)
n Data input
Calibration
84
To Next Page
Loading...
Need help?
General
