85
12 Configuration
is made from the standby output. In both cases, the controller determines the optimum control-
ler parameters from the response of the actual value.
Ö Chapter "Optimization according to the oscillation method", page 86
Ö Chapter "Optimization according to the step response method", page 87
Output type 1, 2
The cycle time is calculated on the basis of the type of controller output.
Optimized controller parameters
With both autotuning methods, certain parameters are optimized according to the configured
controller type and configured parameters. The controller structure is derived from the type of
the optimized parameters: Proportional band Xp (P component), derivative time Tv (D compo-
nent), and reset time Tn (I component).
The cycle time Cy and the filter time constant dF are also optimized.
For 1st-order control processes, the parameters required for the PI controller structure are op-
timized, independently of the configured parameters.
Error handling
If the actual value deviates above or below the measuring range during autotuning, autotuning
is aborted. In this case, the configured parameters are not changed.
Configured con-
troller type
Configured parameters Optimized parameters Optimized
controller
structure
Two-state control-
ler
Xp1 = any;
Tv1 = 0; Tn1 > 0
Xp1, Tn1, Cy1, dF PI
All other settings Xp1, Tv1, Tn1 Cy1, dF PID
Three-state con-
troller
Xp1 = Xp2 = any;
Tv1 = 0; Tn1 > 0
Xp1, Xp2, Tn1, Cy1, Cy2, dF PI
All other settings Xp1, Xp2, Tv1, Tn1, Cy1, Cy2, dF PID
Three-step con-
troller
Xp1 = any;
Tv1 = 0; Tn1 > 0
Xp1, Tn1, dF PI
All other settings Xp1, Tv1, Tn1, dF PID
Continuous con-
troller
Xp1 = any;
Tv1 = 0; Tn1 > 0
Xp1, Tn1, dF PI
All other settings Xp1, Tv1, Tn1, dF PID
Position control-
ler
Xp1 = any;
Tv1 = 0; Tn1 > 0
Xp1, Tn1, dF PI
All other settings Xp1, Tv1, Tn1, dF PID
WARNING!
During autotuning according to the oscillation method, output value limits Y1 and Y2 are not
active for switched outputs or solid state outputs.
The output level may exceed or fall below the set limits.
It must be ensured that this does not result in damage to the plant.
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