West Control Solutions KS 92-1 Programmer manual - Manual (Page 17)

3.5.3 Selecting the method ( ConF/ Cntr/ tunE)
Selection criteria for the optimization method:
Step attempt after start-up Pulse attempt after start-up Optimization at the set-point
tunE = 0 sufficient set-point reserve is
provided
sufficient set-point reserve is not
provided
tunE = 1 sufficient set-point reserve is
provided
sufficient set-point reserve is not
provided
tunE = 2 always step attempt after
start-up
Sufficient set-point reserve:
inverse controller:(with process value < set-point- (10% of
rnGH - rnGL)
direct controller: (with process value > set-point + (10% of rnGH - rnGL)
3.5.4 Step attempt after start-up
Condition: - tunE = 0 and sufficient set-point reserve provided or
- tunE = 2
The controller outputs 0% correcting variable or Y.Lo and waits, until the process
is at rest (see start-conditions on page 8).
Subsequently, a correcting variable step change to 100% is output.
The controller attempts to calculate the optimum control parameters from the pro-
cess response. If this is done successfully, the optimized parameters are taken
over and used for line-out to the set-point.
With a 3-point controller, this is followed by “cooling”.
After completing the 1st step as described, a correcting variable of -100% (100%
cooling energy) is output from the set-point. After successfull determination of
the “cooling parameters”, line-out to the set-point is using the optimized parame-
ters.
3.5.5 Pulse attempt after start-up
Condition: - tunE = 1 and sufficient set-point reserve provided.
The controller outputs 0% correcting variable or Y.Lo and waits, until the process
is at rest (see start conditions page 8)
Subsequently, a short pulse of 100% is output (Y=100%) and reset.
The controller attempts to determine the optimum control parameters from the
process response. If this is completed successfully, these optimized parameters
are taken over and used for line-out to the set-point.
With a 3-point controller, this is followed by “cooling”.
After completing the 1st step as described and line-out to the set-point, correcting
variable "heating" remains unchanged and a cooling pulse (100% cooling energy)
is output additionally. After successful determination of the “cooling parame-
ters”, the optimized parameters are used for line-out to the set-point.
Operation
KS 90-1
p / KS 92-1 p 17 Self-tuning