Siemens SIMATIC S7-1200 Function Manual page 196

Using PID_Temp
6.4 Cascade control with PID_Temp
Setting in the configuration editor or
Inspector window
Output settings → Output limits and
scaling → OutputHeat / OutputCool:
PID output value low limit (heating),
PID output value high limit (heating),
Scaled low output value (heating),
Scaled high output value (heating)
This tag is not available in the Inspector
window or in the functional view of the
configuration editor.
You can change it via the parameter
view of the configuration editor.
Configuration of a slave
Setting in the configuration editor or
Inspector window
Basic settings → Cascade:
Select the "Controller is slave" check
box
196
DB parameter
Config.Output.Heat.PidLowe-
rLimit,
Config.Output.Heat.PidUppe-
rLimit,
Config.Output.Heat.Lowe-
rScaling,
Config.Output.Heat.Uppe-
rScaling
Config.Cascade.AntiWin-
dUpMode
DB parameter
Config.Cascade.IsSlave =
TRUE
Explanation
If no own scaling function is used when assign-
ing OutputHeat of the master to Setpoint of the
slave, it may be necessary to adapt the output
value limits and the output scaling of the master
to the setpoint/process value range of the
slave.
The Anti-Wind-Up mode determines how the
integral action of this master is treated if directly
subordinate slaves reach their output value
limits.
Options are:
AntiWindUpMode = 0:
•
The AntiWindUp functionality is deactivated.
The master does not react to the limitation
of its slaves.
AntiWindUpMode = 1 (default):
•
The integral action of the master is reduced
in the relationship "Slaves in limita-
tion/Number of slaves". This reduces the ef-
fects of the limitation on the control
behavior.
AntiWindUpMode = 2:
•
The integral action of the master is held as
soon as a slave is in limitation.
Explanation
Activates this controller as a slave in a cascade
Function Manual, 03/2017, A5E35300227-AC
PID control