Introduction
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309297K
Introduction
How the Electrostatic Air
Spray Gun Works
The automatic electrostatic air spray gun operates very
similar to a traditional air spray gun. The atomization
and fan air are emitted from the air cap. The atomization
air breaks up the fluid stream and controls the droplet
size. The fan air controls the shape and width of the
spray pattern. The fan and atomization air can be
adjusted independently.
Operating the Spray
Function
Applying a minimum of 50 psi (0.35 MPa, 3.5 bar) air
pressure to the gun manifold’s cylinder air fitting (CYL)
will retract the gun piston, which opens the air valves
and a short time later opens the fluid needle. This pro-
vides the proper air lead and lag when triggering the
gun. A spring returns the piston when the cylinder air is
shut off.
Operating the Electrostatics
To operate the electrostatics, apply air pressure to the
gun manifold’s turbine air fitting (TA) through a Graco
grounded air hose. The air enters the manifold and is
directed to the inlet of the power supply turbine. The air
spins the turbine, which then provides electrical power
to the internal high voltage power supply. The fluid is
charged by the spray gun electrode. The charged fluid is
attracted to the nearest grounded object, wrapping
around and evenly coating all surfaces.
The turbine air is exhausted into the shroud and out the
back of the manifold through the exhaust fitting (EXH).
The exhaust air helps keep contaminants out and helps
keep the gun clean.
Gun Features and Options
•
The gun is designed for use with a reciprocator, and
can be mounted directly on a 1/2 in. (13 mm) rod.
With additional brackets, the gun can be mounted
for robotic applications.
•
The gun’s quick-disconnect design enables its
removal without disconnecting the fluid and air lines
to the gun.
•
Gun functions are activated from a separate control-
ler that sends the appropriate signal to the actuating
solenoids.
•
The optional fiber optic readout system can be
installed to monitor the gun’s spraying voltage. A
fiber optic cable connected to the gun manifold car-
ries the signal from the gun to a remote display
module. Part No. 224117 Display Module displays
the gun’s spraying voltage and current. Bat-
tery-operated Display Module 189762 displays the
gun’s spraying voltage only.
Changing the kV Setting
The gun’s full voltage setting is 85 kV. Three lower volt-
age settings are possible by actuating the KV1 and KV2
switches. Supply 50 psi (0.35 MPa, 3.5 bar) air pressure
to the KV1 and KV2 ports. Turn the air on or off as
shown in Table 1 to set the desired voltage.
The solenoid valves used to activate the KV1 and KV2
switches must bleed the air out of the lines for the
switches to draw back to the higher voltage setting.
Table 1: KV1 and KV2 Switch Settings
KV1 Air
KV2 Air
Output Voltage (kV)
OFF
OFF
85
OFF
ON
70
ON
OFF
60
ON
ON
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Summary of Contents for PRO Auto Xs Series
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