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5 - Automatic tune
5 AUTOMATIC
TUNE
Start/stop of the Fuzzy Tuning
The Tuning operation can be
started or stopped any time.
The green led { blinking goes on
when the Fuzzy Tuning is in
progress. At the end of this opera-
tion, the calculated PID terms para-
meter are stored and used by the
control algorithm and the controller
goes back to the operator mode.
The green led
{ becomes off.
This function allows the calculation
of the optimal PID terms parame-
ters, monitoring the response of the
process to disturbances.
The controller provides 2 types of
“one shot” tuning algorithm, that
are selected automatically accord-
ing to the process condition when
the operation is started.
Step response
This type is selected when, at the
start of the autotune operation, the
PV is far from the Setpoint of more
than 5% of the span.
This method has the big advantage
of fast calculation, with a reasonable
accuracy in the term calculation.
Natural frequency
This type is selected when the PV is
close to the SP Setpoint.
This method has the advantage of
a better accuracy in the term cal-
culation with a reasonable speed
calculation.
The Fuzzy Tuning determines
automatically the best method to
use to calculate the PID term,
according the process conditions.