Pid Auto-Tune And The Pid Tuning Control Panel - Siemens SIMATIC S7-200 System Manual

PID Auto-Tune and the PID Tuning
Control Panel
PID Auto-Tune capability has been incorporated into the S7-200 PLCs and STEP 7--Micro/WIN
has added a PID Tuning Control Panel. Together, these two features greatly enhance the utility
and ease of use of the PID function provided in the S7-200 Micro PLC line.
Auto-tune can be initiated by the user program from an operator panel or by the PID Tuning
Control Panel. PID loops can be auto-tuned one at a time or all eight loops can be auto-tuned at
the same time if necessary. The PID Auto-Tune computes suggested (near optimum) values for
the gain, integral time (reset) and derivative time (rate) tuning values. It also allows you to select
tuning for fast, medium, slow or very slow response of your loop.
With the PID Tuning Control Panel you can initiate the auto-tuning process, abort the auto-tuning
process and monitor the results in a graphical form. The control panel displays any error
conditions or warnings that might be generated. It also allows you to apply the gain, reset and rate
values computed by auto-tune.
In This Chapter
Understanding the PID Auto-Tune
Expanded Loop Table
Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Auto-Hysteresis and Auto-Deviation
Auto-Tune Sequence
Exception Conditions
Notes Concerning PV Out-of-Range (Result Code 3)
PID Tuning Control Panel
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