Substitute Setpoint; Cascade Commissioning - Siemens SIMATIC S7-1200 Function Manual

Using PID_Temp
6.3 Commissioning PID_Temp
6.3.5

Substitute setpoint

The following section describes how you can use the substitute setpoint in the
commissioning window of the "PID_Temp" technology object.
Requirement
● The "PID_Temp" instruction is called in a cyclic interrupt OB.
● An online connection to the CPU has been established.
● The CPU is in "RUN" mode.
Procedure
If you want to use a different value as the setpoint than that specified at the "Setpoint"
parameter (for example to tune a slave in a cascade), use the substitute setpoint in the
commissioning window.
Proceed as follows to specify a substitute setpoint:
1. Double-click the "PID_Temp > Commissioning" entry in the project tree.
2. Activate the "Monitor all"
An online connection will be established.
3. Select the "Subst.Setpoint" check box in the "Online status of controller" section.
The substitute setpoint (SubstituteSetpoint tag) is initialized with the most recently
updated setpoint and now used.
4. Enter the substitute setpoint in the editable field.
5. Click the
Result
The substitute setpoint is written to the CPU and immediately goes into effect.
Clear the "Subst.Setpoint" check box if the value at the "Setpoint" parameter is to be used
again as setpoint.
The switchover is not bumpless.
6.3.6

Cascade commissioning

Information about cascade commissioning with PID_Temp is available under Commissioning
(Page 197).
190
button or start the trend view.
icon.
Function Manual, 03/2017, A5E35300227-AC
PID control