Siemens SIMATIC S7-1200 Function Manual page 451

Manipulated value processing
You can use the LMNLIMIT function to limit the manipulated value to selected values. Alarm
bits indicate when a limit is exceeded by the input variable.
The LMN_NORM function normalizes the output of LMNLIMIT according to the following
rule:
LMN = (output of LMNLIMIT) * LMN_FAC + LMN_OFF
LMN_FAC has a default of 1 and LMN_OFF a default of 0.
The manipulated value is also available in I/O format. The CRP_OUT function converts the
LMN floating-point value to a I/O value according to the following rule:
LMN_PER = LMN * 27648 / 100
Feedforward control
A disturbance variable can be added at the DISV input.
PID control
Function Manual, 03/2017, A5E35300227-AC
Instructions
9.4 PID basic functions
451