Commissioning
Liquisys M CLM223/253
40
Hauser
Feedforward control to PID controller
For control systems with very short reaction times, you can optimize the control.
Additionally you measure the flow rate of the medium. This flow rate value (0/4 to 20 mA)
you apply as feedforward control to the PID controller.
Feedforward control is a multiplying function as illustrated in the figure below (example
with factory setting):
a0008942
Fig. 26: Multiplying
feedforward control
Y
Gain K
infl
X
Current input signal [%]
Z7
Input value, when gain K
infl
= 1
1
0
20
40
60
80
100
Z7
1.5
0.5
Y
X
Summary of Contents for Liquisys M CLM223/253
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