West Control Solutions D280-1 - Manual (Page 18)

4.3 Self-tuning
After starting by the operator, the controller makes a self-tuning attempt. The
controller uses the process characteristics for quick line-out to the set-point wit-
hout overshoot.
g
Self-tuning start can be locked via BlueControl (engineering tool) ( P.Loc).
g
ti and td are taken into account only, if they were ¹ OFF previously.
4.3.1 Self-tuning start (
Щ + И )
The operator can start self-tuning at any time. For
this, keys Ù and È must be pressed simultane-
ously. The AdA LED starts blinking.
The controller outputs 0% or
Y.Lo, waits until the
process is at rest and starts self-tuning (AdA LED
lit permanently).
The self-tuning attempt is started when the following prerequisite is met:
w The difference between process value i set-point must be ³ 10% of the
set-point range ( SP.Hi - SP.LO) (with inverse action: process value smaller
than set-point, with direct action: process value higher than set-point).
After successful self-tuning, the AdA-LED is off and the controller continues
operating with the new control parameters.
4.3.2 Self-tuning cancellation
By the operator:
Self-tuning can always be cancelled by the operator. For this, press Ù and È
key simultaneously. The controller continues operating with the old parameters.
By the controller:
If the Err LED starts blinking whilst self-tuning is running, successful self-tuning
is prevented due to the control conditions. In this case, self-tuning was cancelled
by the controller.
Dependent of control type, the output status is:
w 3-pnt. stepping controller:
actuator is closed (0% output)
w 2-pnt./ 3-pnt./ continuous controller:
If self-tuning was started from the automatic mode, the controller output is
0%. With self-tuning started from manual mode, the controller output is Y2.
Controller
18 Self-tuning Digital 280-1
FUNC
ADA
OUT1
OUT2
OUT3
ERR
Digital 280-1