10ć17 – Rockwell Automation 1771-QDC, D17716.5.86(Passport) PLASTIC MOLDING MODULE User Manual
Page 225

Tune Your Machine
Chapter 10
10-17
Important: The QDC module always logically bridges the injection, pack
and hold phases as a single integrated machine movement.
Bridging machine phases has benefits such as:
reduced cycle time
smoother QDC control
less chance of hydraulic pressure transients
If your hydraulics and/or process require changes controlled by your
PLC-5 processor before continuing a molding cycle, you may configure
the QDC module to stop as completion of:
hold (HPC03-B08 = 1)
pre-decompression (HPC03-B09 = 1)
plastication (PPC03-B08 = 1)
Then the QDC module sends a fixed signal to each of its four outputs
while awaiting further commands from the PLC-5 processor.
Important: The QDC module always stops and sets outputs at completion
of the post-decompression movement.
EndĆofĆprofile SetĆoutput Values
End-of-profile set-output values have uses including:
adjusting flow through a variable pump between profiles
initializing valves for the next profile or movement
re-aligning solenoid valves by PLC-5 processor before starting the next
profile or movement
When configuring end-of-profile set-output values, remember:
The QDC module ignores these values on all profiles that are logically
bridged to the next profile or movement
After the QDC module sets them, they remain in set until the QDC
module is commanded to start another movement or profile, or until the
stop command is asserted
Lengths for PreĆ and PostĆdecompression Pullback
(for preĆdecompression PRC05)
(for postĆdecompression PSC05)
Pre-decompression separates plastic solidifying in the sprue from the
molten cushion remaining in the barrel. The QDC module applies pre-
decompression pullback to the ram (screw) after hold, before plastication.
Decompression Pullback