11.4 Control parameter [xp]
The xp value is the controller amplification factor. The xp value relates to the measuring range end
of a controller and is entered as an absolute value. For pH for example xp=1.5.
For measured variables such as chlorine, the sensor measuring range is selected. The sensor
measuring range corresponds to the measuring range end.
For pH, the measuring range end is 15.45. Here the default xp value is 1.54 (corresponds to ± 1.54
pH). The xp value states that for a deviation of ± 1.54 from the setpoint, the control variable equals ±
100%. The smaller the xp value, the more
‘forcefully’
the control reacts, however the control also
moves slightly into the over-control range.
Measured value
Setpoint
Control variable
A1473
Fig. 87: The smaller the xp value, the more "forcefully" the control reacts.
Setting the
[Control]
129