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User manual SCAIME:
NU-Soft-eNod4F-E-0716_235704-C.doc
parameter will degrade stability, reduce the rise time and increase the overshoot.
•
T
i
:
integration time constant of the PID controller that drives the extraction device, expressed in ms. An
increase of this parameter will reduce the steady state error but will degrade stability and increase time
rise and overshoot.
•
Td :
derivate time constant of the PID controller that drives the extraction device. Adding some derivate
can improve time rise and overshoot. The great majority of extraction devices don't accept derivate
correction or a very low value for the derivate term.
•
PID behaviour:
eNod4
is fitted with an automatic adjustment device of the PID parameters. Slow, Fast or
stable behaviour can be selected by the
PID behaviour
variable that takes
2
,
1
or
0
values respectively.
•
PID adjustment flow rate:
flow rate value that will be used for the automatic adjustment of PID
parameters. In addition to the
PID behaviour
variable, the variable has to be defined previously to the
PID
parameters auto-adjustment
command execution.
•
Number of cycles for PID adjust:
It’s the number of cycles during which PID coefficients are calculated. If
this number is large, sequence will be longer but computing accuracy will be greater. We advise to fix this
number at 10.
