Rockwell Automation 1771-QDC, D17716.5.85(Passport) MNL. PLASTIC MOLDING MODULE - Manual (Page 132)

Span Your Valves
Chapter 9
9-15
Span Your Pack and Hold Pressure Valves
Span your pack valve for smooth operation at the highest desired pressure.
Do this in the following procedure by finding optimum values for words:
Title of Word Pack Word (Address) Hold Word (Address)
Minimum Pressure Control Limit PKC41 (N44:157) HDC41 (N44:217)
Maximum Pressure Control Limit PKC42 (N44:158) HDC42 (N44:218)
Selected Pressure Valve, Output for Minimum PKC43 (N44:159) HDC43 (N44:219)
Selected Pressure Valve, Output for Maximum PKC44 (N44:160) HDC44 (N44:210)
Important: If using the same valve for pack and hold with similar values
in PKC and HDC, span this valve for pack and hold at the same time.
When you enable the pack profile, the QDC module automatically runs the
pack and hold profiles in succession. If using different valves for pack and
hold or substantially different hydraulic circuit during the profiles, span the
pack valve first. Then repeat the procedure for the hold valve.
Important: If PanelView is available, use it to:
observe actuals
change and download setpoints
run profiles
Important: We suggest that you read this procedure before starting.
1. Manually jog your ram (screw) to the mold-end position so you can
exert maximum pressure against the nozzle tip.
2. Align all other machine hydraulics to simulate pack and hold:
enable pumps and align valves to their normal state for pack or hold.
3. Copy initial values PKC09-12 into DYC09-12 (N40:121-124) of your
PLC-5 data table with this exception:
Important: Enter a value corresponding to zero pressure into the word
DYC09-12 (N40:121-124) for output 1, 2, 3, or 4 that drives the selected
ram (screw) pressure valve.
ATTENTION: A value of zero does not necessarily correspond
to zero pressure. For example, a bi-directional valve would
require a set-output value of 50% (5000) to obtain 0 PSI.