Rockwell Automation 1771-QDC, D17716.5.87(Passport) CLAMP AND EJECT MODE - Manual (Page 166)

Span Your Clamp and Ejector Valves
Chapter 9
9-30
Ejector Retract
1. Jog your ejectors to the full retracted position.
2. Align all other machine hydraulics to simulate Ejector Retract. For
example, if certain pumps are enabled during Ejector Retract, enable
them at this time. If a certain valve alignment exists during Ejector
Retract, line the valves up accordingly at this time.
3. Enter a value that should produce minimum pressure into the
set-output word (DYC09, DYC10, DYC11, or DYC12)
corresponding to the selected valve for Ejector Retract pressure
control. Enter all other unselected valve set-output values to what
you would normally use during Ejector Retract (copy ERC09-12 into
DYC09-12).
ATTENTION: A value of 0 entered in your data table does not
necessarily correspond to zero pressure or flow. For example, a
bi-directional valve would require a set-output value of 50%
(5000) to obtain 0 PSI. Amplifier electronics or valve spools
may also be designed such that 0 volts signal input does not
correspond to no flow or pressure. Please consult your valve
and amplifier specifications for more details.
4. Enable set-output by transitioning DYC01-B08 (Pro-Set 600 address
B35/392) from a 1 to a 0.
5. Observe the pressure reported back in SYS26 (Pro-Set 600 address
N41:178).
If this pressure is greater than zero, marginally adjust the selected
Ejector Retract valve set-output value in an attempt to obtain zero
pressure feedback. Stop the adjustments when you observe the
smallest pressure attainable. This procedure may be required on a
bi-directional valve with a spool offset.
If this pressure is zero, marginally adjust the selected Ejector
Retract valve set-output value until the observed pressure feedback
just becomes greater than zero, and then re-adjust the value until
you just observe zero again. This procedure may be required on a
uni-directional valve with no response at low signal levels.
6. Once you are satisfied you have obtained the lowest possible pressure
(bi-directional valve), or the highest possible signal at zero pressure
(uni-directional valve), copy the pressure observed in SYS26 (usually
0 PSI or Bar) into ERC41 (Pro-Set 600 address N45:97), the
Minimum Ejector Retract Pressure Control Limit.