Rockwell Automation 1771-QDC, D17716.5.86(Passport) PLASTIC MOLDING MODULE - Manual (Page 238)

Tune Your Machine
Chapter 10
10-30
End-of-profile set-output values have uses including:
setting cores between clamp close profiles
pulling cores between clamp open profiles
third plate drop-off and pick-up
building tonnage/holding pressure on the clamp prior to injection
adjusting flow with a variable pump after clamping or 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
The zero ramp rates that you entered in chapter 7 disabled ramping. This
forced the QDC module to step from setpoint to setpoint during a profile.
If required by your application, you may configure your QDC module to
ramp its outputs during any profile. The QDC module uses configured
acceleration and deceleration ramp rates when moving all of its outputs
from setpoint to setpoint during any profile (figures 10.4 and 10.5).
ATTENTION: Because ramp rates are time based, using very
slow (low value) ramp rates may inhibit effective closed- loop
control, reduce ERC calculation accuracy, and limit the QDC
module’s control capability. Use ramp rates only if machine
operation mandates them.
Important: When enabled, the QDC module applies ramp rates at the
beginning of each profile segment.
With caution, you can use ramp rates to smooth jerky motion resulting
from large changes in clamp pressure or flow.
Acceleration and
Deceleration
Ramp Rates