Scaime eNod4-B - Calibration of Flow Rate; PID Parameters Auto-Adjustment; Stop & Restart Pid; Clear Great Total

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User manual SCAIME: NU-soft-eNod4B-E-0716_236704-C.doc
10.3.29 Calibration of flow rate
So that eNod4 can carry out an expected flow rate dosing in the best conditions possible, the flow rate output control
calibration is required. This also applies when eNod4 is used both as belt scale or belt weigh feeder.
From this calibration will depend the accuracy of the flow rate obtained and on the actuation time delay, if a PID
regulator controls it. This calibration is carried out in minimum two segments by the variable segments number for
the calibration curve of flow rate. In case the extraction device has a nonlinear response it is recommended to define
maximum segments for the flow rate calibration.
If the control of extraction device is directly provided by eNod4 through a control analog output in current or voltage,
analog output of eNod4 must be allocated to level on request function first.
For each calibration point of the variable control output value, read the appropriate average flow rate. Then provide
each of the Calibration of control output point n / analog output and Calibration of flow rate point n matching with
control output value. Validate the flow rate calibration by sending “calibration of flow rate” command.
Allocate in the end the current or voltage analog output of eNod4 to flow rate control output function.
10.3.30 PID parameters auto-adjustment
The configuration of the plan of regulation can be made in a totally automatic way. The behavior of PID regulation
(slow, fast or stable) must beforehand be configured. Also, you have to configure reference flow rate used in PID auto-
adjustment.
So that this plan of regulation works, it is necessary that weight calibration indication as well as flowrate calibration
is beforehand realized.
“PID parameters auto-adjustment” command will cause eNod4 to perform special sequence on belt system and to
calculate optimized PID coefficients Kp, Ti and Td.
It is strongly recommended that Td parameter does not exceeded value 5.
10.3.31 STOP & RESTART PID
We can STOP and RESTART PID at each cycle step. When PID is stopped, analog output pilots belt to nominal value.
10.3.32 Clear great total
“Clear great total” command allows only resetting “Grand total (in weight unit x1000)” totalization result.
10.3.33 Clear general total
“Clear general total” command allows only resetting “General total (in weight unit x1000)” totalization result.