Configure Controller Difference Cont_C - Siemens SIMATIC S7-1200 Function Manual

Using PID basic functions
7.1 CONT_C
7.1.2

Configure controller difference CONT_C

Use process value periphery
To use the process value in the periphery format at the PV_PER input parameter, follow
these steps:
1. Select the "Enable I/O" check box.
2. If the process value is available as a physical size, enter the factor and offset for the
scaling in percent.
The process value is then determined according to the following formula:
PV = PV_PER × PV_FAC + PV_OFF
Use internal process values
To use the process value in the floating-point format at the PV_IN input parameter, follow
these steps:
1. Clear the "Enable I/O" check box.
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
How CONT_C works (Page 450)
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Function Manual, 03/2017, A5E35300227-AC
PID control