Siemens SIMATIC S7-1200 Function Manual page 243

● Default value of PID parameters
The following default settings have been changed:
– Proportional action weighting (PWeighting) from 0.0 to 1.0
– Derivative action weighting (DWeighting) from 0.0 to 1.0
– Coefficient for derivative delay (TdFiltRatio) from 0.0 to 0.2
● Renaming tags
The static tags have been given new names that are compatible with PID_3Step.
PID_Compact V1.2
● Manual mode on CPU startup
If ManualEnable = TRUE when the CPU starts, PID_Compact starts in manual mode. A
rising edge at ManualEnable is not necessary.
● Pretuning
If the CPU is switched off during pretuning, pretuning starts again when the CPU is
switched back on.
PID_Compact V1.1
● Manual mode on CPU startup
When the CPU starts up, PID_Compact only switches to manual mode with a rising edge
at ManualEnable. Without rising edge, PID_Compact starts in the last operating mode in
which ManualEnable was FALSE.
● Reaction to reset
A rising edge at Reset resets the errors and warnings and clears the integral action. A
falling edge at Reset triggers a switchover to the most recently active operating mode.
● Default of process value high limit
The default value of r_Pv_Hlm has been changed to 120.0.
● Monitoring the sampling time
– An error is no longer output when the current sampling time is ≥ 1.5 x current mean
– PID_Compact is compatible with FW, V2.0 or higher.
PID control
Function Manual, 03/2017, A5E35300227-AC
value or when the current sampling time is ≤ 0.5 x current mean value. The sampling
time may deviate much more in automatic mode.
Instructions
9.1 PID_Compact
243