Mode Of Operation - Siemens SIMATIC S5 Manual

1.2.2 Mode of Operation

Fig. 1.2.1/1 shows the structure of the temperature controller with self-tuning function.
In addition to the PID controller as described in Chapter 1, the following functions are also included:
– self-tuning,
– parameter monitoring,
– PID controller in rugged design.
– The "self-tuning function" performs a process identification and determines the optimum
controller parameters. It also controls the process during the self-tuning phase. On
completion of the self-tuning, the rugged PID controller takes over process control.
– The "parameter monitoring" function checks whether the controlled system has changed its
characteristics, if necessary reduces the controller gain and increases the integral action
time.
– A rugged PID controller is obtained from the conventional PID control algorithm, which is not
sensitive to small control system changes as caused, for example, by plastic-granulate
change.
IP244
C79000–B8576–C860–02
Description of the Firmware
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