Graco 234129, Инструкция по эксплуатации

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Configuring Software
38 309738L
On/Off Delays
The PrecisionFlo LT regulator can physically respond
faster than the dispense device and its solenoid. As a
result, the regulator can supply material to the dispense
device before the device has time to open. Supplying
material to a closed device can create trapped-pressure.
At the end of a cycle, the dispense device can shut off
before the pressure has dissipated. This can cause a
dispense of an excess of material at the beginning of the
next cycle.
To eliminate these two problems, you can change the
delay time associated with the opening of the regula-
tor/dispense and/or the closing of the dispense device,
see
Table 7 - On/Off Delay Variables .
In general, your outlet pressure on the screen during “no
flow” should be slightly below the outlet pressure during
dispense. If your dispense hose to the gun is creating
too much pressure drop during flow, you may want the
no flow reading to be lower. High trapped pressures
shorten the dispense device life.
Table 7 - On/Off Delay Variables
F
IG
. 18 and Table 8 - Delay On/Off Timing show delay
ON and OFF timing.
Table 8 - Delay On/Off Timing
Regulator Pre-Charge
Another method which can be used to increase the dispense hose pressure while the dispense valve is closed is to
use a regulator pre-charge. Setting this value to a range of 1.00 to 5.00 VDC causes the V/P to apply 0 to 100 psi (.60
MPa, 68 bar) air pressure to the fluid regulator. Typical values entered would be about 1.2 VDC.
Variable: Sets the Amount of Time:
Gun ON Sets time from Dispense Gun High to
Gun Open command
Regulator ON Sets time from Dispense Gun High to
Regulator ON
Gun OFF Sets time from Dispense Gun Low to
Gun Close command
Regulator
OFF Sets time from Dispense Gun Low to
Regulator OFF
F
IG
. 18
D
C
A
B
Dispense Gun
Signal
PrecisionFlo LT
Regulator
Gun Open
Command
Gun Actually
Open
E
F
A Regulator ON delay The user sets the regulator ON delay timing.
B Gun ON delay Usually set to zero. Can be used to change the starting point of a bead.
C Gun OFF Delay Usually set to zero. Higher values will lower the trapped pressure.
D Regulator OFF delay The user sets the regulator OFF delay timing. Zero or small values will lower the
trapped pressure.
E Gun Open Reaction
Time Time delay for gun to physically open. Delay varies based on pneumatic hose length
and valve air volume.
F Gun Close Reaction
Time Time delay for gun to physically close. Delay varies based on pneumatic hose length
and valve air volume.