Rievtech xLogic ELC Series User Manual page 178

: Loop error at the time n
The following picture shows a jump in process value and step response of the controller:
Summary
The PI controller has the following characteristics:
The P controller components quickly intercept an occurring loop error.
The I controller components can then remedy the remaining loop error.
The controller components supplement each other so that the PI controller works quickly and precisely.
Description of the individual parameters
Controller parameters
Mn Manipulated variable
at the time n
kP
Gain of the P part
kI
Gain of the I part
Ts Sampling time,
duration of a time slice
TI Integral time
Portrayed in xLogic
Output of the PI controller block
In the xLogic, the parameter KC
applies as an increase for the I part
and the P part of the controller
equally.
Should you enter KC=0, then the P
part of the controller switches off. In
this special case, k is automatically
set to 1 for the I part. If KC = 0: kP =
0 and kI = 1
If KC <> 0: kP = kI = KC
Fixed
Parameter TI, if you set this
parameter to 99:59 min, then you
switch off the I part of the controller.
Possible value range in the xLogic
0 to 1,000
0.00 to 99.99
500 ms
00:01 min to 99.59 min
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