Rockwell Automation 1771-QDC, D17716.5.86(Passport) PLASTIC MOLDING MODULE - Manual (Page 240)

Tune Your Machine
Chapter 10
10-32
You can configure ramp rates to decelerate the clamp:
at the beginning of low pressure close. This may avoid possible damage
to mold or machinery when moving toward the mold protection zone at
high velocities during the clamp close operation.
at the beginning of open slow. This may help achieve consistent
repeatability of the full open position when moving toward the open
slow zone at high velocities during the clamp open operation.
If your application requires the use of ramp rates, remember:
Never apply ramp rates until you tuned all applicable clamp pressure
and velocity loops.
You can apply ramp rates to selected and unselected valves. Therefore,
even though you may be controlling velocity, you can ramp clamp
pressure during low pressure close.
Ramp rates and ERC may not function properly together. Be very
careful if applying ERC and ramp rates in the same profile.
Using slow ramp rates may force pressure and velocity actuals out of
control because these actuals include the time spent ramping plus the
time each segment is controlled.
The QDC module uses ramp rates upon entry into a profile and when
stepping between segments in that profile. See figures 10.4 and 10.5.
You enter ramp rates in units of 0 to 9999% signal output per second
(note that there is no decimal point). A ramp rate entry of 9999 lets the
output move full range in 10 milliseconds, while a ramp rate entry of 99
requires a full second to go full range. Lower values = slower ramps.
The QDC module monitors high pressures and compares them with two
types of alarm setpoints for:
absolute pressure that you configure in the MCC block (chapter 3)
The QDC module monitors these continuously without regard to current
machine mode or operational cycle.
profile pressure that you configure in configuration blocks (chapter 7)
The QDC module monitors these only during the subject profile.
Pressure Alarm Setpoints