Siemens SIMATIC S7-1200 Function Manual page 261

Tag
Retain.CtrlParams.Ti
Retain.CtrlParams.Td
Retain.CtrlParams.TdFiltRatio
Retain.CtrlParams.PWeighting
PID control
Function Manual, 03/2017, A5E35300227-AC
Data type Default
REAL 20.0
REAL 0.0
REAL 0.2
REAL 1.0
Description
CtrlParams.Ti > 0.0: Active integral action time
•
CtrlParams.Ti = 0.0: Integral action is deactivated
•
Ti is retentive.
CtrlParams.Td > 0.0: Active derivative action time
•
CtrlParams.Td = 0.0: Derivative action is deac-
•
tivated
Td is retentive.
Active derivative delay coefficient
The derivative delay coefficient delays the effect of the
derivative action.
Derivative delay = derivative action time × derivative
delay coefficient
0.0: Derivative action is effective for one cycle only
•
and therefore almost not effective.
0.5: This value has proved useful in practice for
•
controlled systems with one dominant time con-
stant.
> 1.0: The greater the coefficient, the longer the
•
effect of the derivative action is delayed.
TdFiltRatio is retentive.
Active proportional action weighting
The proportional action may weaken with changes to
the setpoint.
Values from 0.0 to 1.0 are applicable.
1.0: Proportional action for setpoint change is fully
•
effective
0.0: Proportional action for setpoint change is not
•
effective
The proportional action is always fully effective when
the process value is changed.
PWeighting is retentive.
Instructions
9.1 PID_Compact
261