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SCAIME Manual : NU-eNod4B-ETH-E-236708-D.docx
12.2.6
PID
Parameter
Possible Value
Description
PID parameters
PID activation
Yes / No
eNod4 adjusts the speed of the extraction device to produce a constant
flow rate and to comply with flow rate target setting.
Behavior
Slow / Fast /
Stable
eNod4 is fitted with an automatic adjustment device of the PID
parameters. Slow, Fast or stable behaviour can be selected.
PID adjustement
Flow Rate
Flow rate value that will be used for the automatic adjustment of PID
parameters.
Kp
Proportional coefficient of the PID controller that drives the extraction
device. An increase of this parameter will degrade stability, reduce the rise
time and increase the overshoot.
Ti
0 - 65535
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
0 - 65535
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.
Launch automatic adjustment of PID. So that this controller automatic
adjusting device works, both the weight calibration and the flowrate
calibration must be previously carried out. PID parameters auto-
adjustment command will cause eNod4 to perform successive dosing cycle
(10) sequences to calculate optimized PID coefficients Kp, Ti and Td.
