West Control Solutions KS 92-1 Programmer manual - Manual (Page 16)

3.5.1 Preparation for self-tuning
Adjust the controller measuring range as control range limits. Set
values
rnG.L and rnG.H to the limits of subsequent control.
(Configuration r Controllerrlower and upper control range limits)
ConFrCntrr rnG.L and rnG.H
w Determine which parameter set shall be optimized.
- The instantaneously effective parameter set is optimized.
r Activate the relevant parameter set (1 or 2).
w Determine which parameter set shall be optimized (see tables above).
w Select the self-tuning method
see chapter 3.5.3
-Step attempt after start-up
-
Pulse attempt after start-up
- Optimization at the set-point
3.5.2 Optimization after start-up or at the set-point
The two methods are optimization after start-up and at the set-point.
As control parameters are always optimal only for a limited process range, vari-
ous methods can be selected dependent of requirements. If the process behaviour
is very different after start-up and directly at the set-point, parameter sets 1 and 2
can be optimized using different methods. Switch-over between parameter sets
dependent of process status is possible (see page ).
Optimization after start-up: (see page 4)
Optimization after start-up requires a certain separation between process value
and set-point. This separation enables the controller to determine the control pa-
rameters by evaluation of the process when lining out to the set-point.
This method optimizes the control loop from the start conditions to the set-point,
whereby a wide control range is covered.
We recommend selecting optimization method “Step attempt after start-up”
with
tunE = 0 first. Unless this attempt is completed successfully, we recom-
mend a “Pulse attempt after start-up”.
Optimization at the set-point: (see page 18)
For optimizing at the set-point, the controller outputs a disturbance variable to the
process. This is done by changing the output variable shortly. The process value
changed by this pulse is evaluated. The detected process parameters are con-
verted into control parameters and saved in the controller.
This procedure optimizes the control loop directly at the set-point. The advantage
is in the small control deviation during optimization.
Operation
Self-tuning 16 KS 90-1
p / KS 92-1 p