Configure Controller Algorithm Tcont_S - Siemens SIMATIC S7-1200 Function Manual

Using PID basic functions
7.4 TCONT_S
Use internal process values
To use the input parameter PV_IN, proceed as follows:
1. Select the entry "Internal" from the "Source" list.
Control deviation
Set a dead zone range under the following requirement:
● The process value signal is noisy.
● The controller gain is high.
● The derivative action is activated.
The noise component of the process value causes strong deviations of the output value in
this case. The dead zone suppresses the noise component in the steady controller state.
The dead zone range specifies the size of the dead zone. With a dead zone range of 0.0, the
dead zone is turned off.
See also
Mode of operation TCONT_S (Page 497)
7.4.3

Configure controller algorithm TCONT_S

General
1. Enter the "Sampling time PID algorithm".
A controller sampling time should not exceed 10 % of the determined integral action time
of the controller (TI).
2. If the controller structure contains a proportional action, enter the "proportional gain".
A negative proportional gain inverts the rule meaning.
Proportional action
For changes of the setpoint, it may lead to overshooting of the proportional action. Through
the weighting of the proportional action, you can select how strongly the proportional action
should react when setpoint changes are made. The weakening of the proportional action is
reached through a compensation of the integral action.
1. To weaken the proportional action for setpoint changes, enter a "Proportional action
weighting".
– 1.0: Proportional action for setpoint change is fully effective
– 0.0: Proportional action for setpoint change is not effective
Integral action
1. If the controller structure contains an integral action, enter the "integral action time".
With an integral action time of 0.0, the integral action is switched off.
See also
Mode of operation TCONT_S (Page 497)
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Function Manual, 03/2017, A5E35300227-AC
PID control