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ifm
Programming Manual
ecomatmobile
CabinetController (CR0301) Runtime System V05
2016-04-21
ifm function elements
ifm function elements for the device CR0301
>
PID1
351
Unit type = function block (FB)
Unit is contained in the library
ifm_CR0301_Vxxyyzz.LIB
Symbol in CODESYS:
>
Description
354
PID1 handles a PID controller.
The change of the manipulated variable of a PID controller has a
p
roportional,
i
ntegral and
d
ifferential
component. The manipulated variable changes first by an amount which depends on the rate of
change of the input value (D component). After the end of the derivative action time the manipulated
variable returns to the value corresponding to the proportional range and changes in accordance with
the reset time.
NOTE
The manipulated variable Y is already standardised to the PWM FB (RELOAD value = 65,535). Note
the reverse logic:
65,535 = minimum value
0 = maximum value.
Note that the input values KI and KD depend on the cycle time. To obtain stable, repeatable control
characteristics, the FB should be called in a time-controlled manner.
If X > XS, the manipulated variable is increased.
If X < XS, the manipulated variable is reduced.
The manipulated variable Y has the following time characteristics:
Figure: Typical step response of a PID controller
Summary of Contents for Ecomat 100 Mobile CR0301
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