Rockwell Automation 1771-QDC, D17716.5.87(Passport) CLAMP AND EJECT MODE - Manual (Page 180)

Tune Your Machine
Chapter 10
10-7
Enter an operational profile representative of the movement characteristics
you desire for your production cycle. Zero the appropriate integral and
derivative term(s) associated with the profile(s), leaving the proportional
term(s) at the default settings you entered in chapter 7.
Run several cycles of the profile(s) while observing the oscilloscope trace.
Ideally, for each step of a multi-stepped profile, the oscilloscope trace rises
(or falls) quickly to a controlled level and then “flattens out”. “Bounce” or
“chatter” when rising (or falling) is undesirable.
If: Then:
Your scope trace for any given profile step
never levels off (it is either rising or falling for
the entire step)
Increase proportional term(s)
Your scope trace for any given profile step
rises (or falls) quickly and then bounces" or
chatters" around a voltage/current
Decrease proportional term(s)
Excessive hammering and vibration is
observed in the cylinder's hydraulic lines
Decrease proportional term(s)
Important: Each change to a tuning constant requires you to download
your changes to the QDC module. Refer to the Download Procedure
outlined in chapter 4.
Repeat the profile(s) cycles after each change to the proportional term(s)
until observed oscilloscope traces quickly level off without any bouncing
or chattering.
Without modifying the proportional term(s) determined by the above
procedure, slowly begin increasing the appropriate integral term(s) while
running machine cycles until significant “overshoots” are observed on the
oscilloscope trace. Now decrease the integral term(s) until the overshoot is
no longer observed.
If you cannot alter your proportional and integral term(s) such that
observed oscilloscope traces quickly level off without any bouncing or
chattering, verify your Unselected Valve Set-output Values are correct for
your application (Refer to chapter 7 and the discussion later in this
chapter).