Rockwell Automation 1771-QDC, D17716.5.87(Passport) CLAMP AND EJECT MODE - Manual (Page 176)

Tune Your Machine
Chapter 10
10-3
The remainder of this chapter is presented in two major sections:
In Closed-loop Tuning we discuss the use and effect of the QDC
module’s closed-loop tuning constants and present a procedural
discussion on how to determine their proper settings for your plastic
molding process. If your application does not require operating in
closed-loop, you do not need to refer to this section, and may proceed to
the section entitled Other Tuning Considerations.
In Other Tuning Considerations we discuss the use and effect of many
of the other QDC module setpoint parameters. This section is presented
in a “discussion” format rather than a procedural format similar to
previous chapters. The discussions in this section assume familiarity
with conventions, terminologies, and procedures used in the Injection
Molding Industry and previously in this User’s Manual.
If you Need Information on: Reference:
Downloading modified parameter values
from your PLC processor to your QDC module
Chapter 4
Definitions of configuration block parameters Chapter 7
PMMRM Section 1
PMMRM Section 3
Definitions of profile block parameters Chapter 8
PMMRM Section 1
PMMRM Section 3
PLC data table cross reference to QDC
command and status block words
PMMRM Section 1
Determining appropriate tuning constants for your closed-loop clamp and
ejector movements is essential to ensure smooth, repeatable operation.
Because of the type of dynamic loads present when cycling an injection
molding clamp mechanism, tuning constants large enough to achieve strict
adherence to profile pressure and velocity setpoints are not always
desirable.
Important: When altering the profile (stroke) tuning constants for
closed-loop clamp and ejector control, the user should strive to utilize the
lowest possible settings that yield repeatable, high speed clamp and ejector
cycles.
In chapter 7 of this manual, you entered our recommended closed-loop
tuning constants into the configuration blocks. These values are normally
sufficient to produce the desired clamp and ejector performance when
cycling your machine in closed-loop. If you need to modify the default
closed-loop tuning constants, remember the following:
The QDC module’s velocity control and ERC algorithms should not be
used if a FeedForward tuning constant is applied to the velocity loop
What to do Next
Tune in ClosedĆloop Mode