Graco HFRL, Setup And Operation Manual

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Appendix H- Circulation
3A2175Z 113
Once dispensing, the screen will appear similar to F
IG
.
39. When the dispense is completed (or aborted early
by re-triggering the footswitch during the dispense), the
system will return to the circulation state, the display
will appear as shown in F
IG
. 40, and the material count -
ers will be incremented accordingly.
To stop the circulation process, press the “ ” key
when the pumps are circulating.
Pressurize Before Opening DV
Feature
HFR logic versions 1.12.008 and later, a “Pressurize
Before Opening DV” feature was added to the “Auto
Circulate Between Dispenses” option as indicated in
the Advanced Screen 6 shown below. The new feature
is intended to pressurize the two materials to the cor -
rect values to ensure the mix quality at the dispense
start is optimal. This feature eliminates the need to add
restriction to the material return lines in an attempt to
match the recirculation and dispense pressures.
F
IG
. 40: System Circulating Automatically after a
Shot Mode Dispense
F
IG
. 41: System Circulating Automatically after a
Sequence Mode Dispense
F
IG
. 42: System Circulating Automatically after a
Sequence Mode Dispense in PLC Control
F
IG
. 43: Pressurize Before Opening DV Feature ON