Siemens SIMATIC S7-1200 Function Manual page 104

Using PID_Compact
4.3 PID_Compact V1
Output value limits V1
In the "Output value limits" configuration window, configure the absolute limits of your output
value in percent. Absolute output value limits are not violated in neither manual mode nor in
automatic mode. If a output value outside the limits is specified in manual mode, the effective
value is limited in the CPU to the configured limits.
The valid output value limit values depend on the Output used.
Output
Output_PER
Output_PWM
PID_Compact sets the output value to 0.0 if an error occurs. 0.0 must therefore always be
within the output value limits. You will need to add an offset to Output and Output_PER in the
user program if you want an output value low limit of greater than 0.0.
See also
Process value settings V1 (Page 100)
Process value monitoring V1 (Page 101)
PWM limits V1 (Page 102)
PID parameters V1 (Page 104)
PID parameters V1
The PID parameters are displayed in the "PID Parameters" configuration window. The PID
parameters will be adapted to your controlled system during controller tuning. You do not
need to enter the PID parameters manually.
The PID algorithm operates according to the following equation:
Symbol
y
K
p
s
b
w
x
T
I
a
T
D
c
104
Description
Output value of the PID algorithm
Proportional gain
Laplace operator
Proportional action weighting
Setpoint
Process value
Integral action time
Derivative delay coefficient (derivative delay T1 = a × T
Derivative action time
Derivative action weighting
-100.0 to 100.0
-100.0 to 100.0
0.0 to 100.0
)
D
Function Manual, 03/2017, A5E35300227-AC
PID control