Siemens SIMATIC Manual page 50

Controller Tuning in FB 58 "TCONT_CP"
Damping Control Parameters
If oscillations occur in the closed control loop or if there is overshoot following
setpoint step changes, you can reduce the controller GAIN (for example to 80 % of
the original value) and increase the reset time TI (for example to 150 % of the
original value). If the analog manipulated variable (LMN) of the continuous
controller is converted to binary actuating signals with a pulse generator,
quantization effects can cause small permanent oscillations. You can eliminate
these by extending the controller deadband DEADB_W.
Changing the Control Parameters
To change the control parameters, follow the steps outlined below:
1. Save the current parameters with SAVE_PAR.
2. Change the parameter settings.
3. Test the control response.
If the new parameter settings are worse than the old settings, reload the old
parameters with UNDO_PAR.
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PID Temperature Control
A5E00125039-02