West Control Solutions N8840 - Manual (Page 21)

3.5.4 Self-tuning start
Start condition:
w For process evaluation, a stable condition is required. Therefore, the
controller waits until the process has reached a stable condition after
self-tuning start.
The rest condition is considered being reached, when the process value
oscillation is smaller than ± 0,5% of (rnG.H - rnG.L).
w For self-tuning start after start-up, a 10% difference from (SP.LO ... SP.Hi)
is required.
g
Self-tuning start can be blocked via 8800/8840 Configurator (engineering tool)
( P.Loc).
Strt = 0 Only manual start by pressing keys Ù and È
simultaneously or via interface is possible.
Strt = 1 Manual start by press keys Ù and È simultaneously
via interface and automatic start after power-on and detection
of process oscillations.
Operation
8840 profiler 21 Self-tuning
Ada LED status Signification
blinks Waiting, until process calms down
lit Self-tuning is running
off Self-tuning not activ
or ended
RUN
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