Advanced Settings V1 - Siemens SIMATIC S7-1200 Function Manual

5.3.1.4

Advanced settings V1

Actual value monitoring V1
Configure a warning high and low limit for the process value in the "Process value
monitoring" configuration window. If one of the warning limits is exceeded or undershot
during operation, a warning will be displayed at the PID_3Step instruction:
● At the InputWarning_H output parameter if the warning high limit has been exceeded
● At the InputWarning_L output parameter if the warning low limit has been undershot
The warning limits must be within the process value high and low limits.
The process value high and low limits will be used if you do not enter values.
Example
Process value high limit = 98° C; warning high limit = 90° C
Warning low limit = 10° C; process value low limit = 0° C
PID_3Step will respond as follows:
Process value
> 98° C
≤ 98° C and > 90° C
≤ 90° C and ≥ 10° C
< 10° C and ≥ 0° C
< 0° C
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
Δy
K
p
s
b
w
x
PID control
Function Manual, 03/2017, A5E35300227-AC
InputWarning_H
TRUE
TRUE
FALSE
FALSE
FALSE
Description
Output value of the PID algorithm
Proportional gain
Laplace operator
Proportional action weighting
Setpoint
Process value
InputWarning_L
FALSE
FALSE
FALSE
TRUE
TRUE
Using PID_3Step
5.3 PID_3Step V1
Operating mode
Inactive
Automatic mode
Automatic mode
Automatic mode
Inactive
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