Rockwell Automation 1771-QDC, D17716.5.93(Passport) PLASTIC MOLDING MODULE - Manual (Page 242)

Tune Your Machine
Chapter 10
10-14
Ram (Screw) Position for Transition
(IPC61)
This position setpoint (measured from mold end) determines where
injection ends and pack (or hold) begins (figure 10.3). Enter a position
value equal to or slightly greater than the top-of-cushion position,
depending on whether your part requires additional plastic compressed into
the mold during pack and hold.
Ram (Screw) Pressure for Transition
(IPC62)
If actual ram (screw) pressure during injection exceeds this setpoint, the
QDC module transitions to the pack phase. Typically you enter a value
less than mold flash pressure.
Start of Zone for Pressure Transition
(IPC64)
A non-zero value (measured from mold end) forces the QDC module NOT
to transition on pressure until the ram (screw) reaches this position (figure
10.3). Use this setpoint to prevent nuisance pressure transitions due to
pressure spikes during the early phases of the injection profile. Typically,
you can inhibit pressure transitions over 50% of shot size without flashing
the mold.
Figure 10.3
Static Setpoints for the Injection Profile
Backpoint Mold end
Cushion
Shot Size
Transition Position
Zone for Pressure Transition
Direction of Ram (Screw) Travel
IPC64
Time Limit for Transition
(IPC60)
The QDC module transitions from injection to pack (or hold) if the total
injection profile time equals or exceeds this setpoint. Use this value as a
safety watchdog if some condition prevents the injection profile from
completing in a timely fashion.