Rockwell Automation 1771-QDC, D17716.5.93(Passport) PLASTIC MOLDING MODULE - Manual (Page 207)

Span Your Valves
Chapter 9
9-41
To do this: change PLC41 and/or PLC43, download the block, and
repeat steps 2-4. Repeat as necessary.
Important: If downloading from your programming terminal, download
PLC followed by PPC with download bits B21/13 and 14 (chapter 4).
What You Have Accomplished
The open-loop tuning procedure you just completed has defined the:
range of ram (screw) backpressure during plastication
end-of-range maximum and minimum signal levels for linear control of
the plastication pressure valve in open-loop control
For this
range limit
When trying to obtain
the pressure in:
The QDC module drives the selected
pressure valve to % output signal in:
Minimum PLC41 PLC43
Maximum PLC42 PLC44
Now for open-loop plastication profiles, the QDC module assumes a liner
relationship between backpressure and signal output.
Set the Profile Pressure Alarm
Set the maximum pressure alarm PLC57 (N44:413) equal to a back-
pressure that should:
not be exceeded during the plastication profile
not be greater than PLC42 (N44:398) maximum pressure control limit
Entering zero disables this alarm.
Download the PLC block to the QDC module.
Important: If downloading from your programming terminal, download
PLC followed by PPC with download bits B21/13 and 14 (chapter 4).