Gun Overview
How the Electrostatic AA Spray Gun
Works
This is not an air spray gun. To help prevent
serious injury from pressurized fluid, such as skin
injection, and splashing fluid, read and follow the
Skin Injection Hazard Warnings on page 5.
The air-assisted spray gun combines airless and
air spraying concepts. The spray tip atomizes
and shapes the fluid into a fan pattern, as does
a conventional airless spray tip. Air from the air
cap further atomizes the fluid and completes the
atomization of the fluid tails to produce a uniform
pattern.
As the gun is triggered, part of the regulated air
operates the alternator turbine and the rest of the
air helps atomize the fluid being sprayed. The
alternator generates power, which is converted by
the power cartridge to supply high voltage to the
gun’s electrode.
The gun’s internal power supply provides high
voltage. The fluid is electrostatically charged as it
passes the electrode. The charged fluid is attracted
to the grounded workpiece, wrapping around and
evenly coating all surfaces.
The regulated air that is directed to the air cap can
be further controlled using the gun’s atomizing air
adjustment valve. This valve can be used to restrict
air flow to the air cap while maintaining sufficient air
flow to the alternator. The atomizing air adjustment
valve does not control pattern width. To change
pattern width, use a new tip size, or use the fan
adjustment to narrow the pattern width.
The high working fluid pressure of this gun provides
the power needed to atomize higher solids materials.
NOTE: For airless atomization, if desired, turn the
gun’s atomizing air adjustment valve completely off.
Closing this valve does not affect alternator operation.
Spraying Waterborne Fluids
Electrostatically
This electrostatic air-assisted spray gun is designed
to spray only waterborne fluids which meet the
following flammability requirements:
• FM, FMc Approved:
Material does not sustain burning in accordance
with the Standard Test Method for Sustained
Burning of Liquid Mixtures, ASTM D4206.
• CE-EN 50059 Compliant:
Materials which cannot be ignited, in any mixture
with air, by an energy source of less than 500mJ.
When connected to a voltage isolation system,
all of the fluid in the spray gun, fluid hose, and
isolated fluid supply is charged to high voltage,
which means that the system has more electrical
energy than a solvent-based system. Therefore,
only non-flammable fluids (as defined under
) can be sprayed with the system or
be used to clean, flush, or purge the system.
Precautions must be taken when using electrostatic
waterborne equipment to avoid potential shock
hazards. When the spray gun charges the isolated
fluid to high voltage, it is similar to charging a
capacitor or a battery. The system will store some of
the energy while spraying and retain some of that
energy after the spray gun is shut off. Do not touch
the gun nozzle or come within 4 in. (102 mm) of
the electrode until the stored energy is discharged.
The amount of time it takes to discharge the
energy depends on the system design. Follow the
Fluid Voltage Discharge and Grounding Procedure,
before approaching the front of the gun.
The Graco warranty and approvals are void if the
electrostatic spray gun is connected to a non-Graco
voltage isolation system or if the gun is operated
above 60 kV.
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