Introduction - Graco PRO 5500wb Instructions-Parts List Manual

Spraying Waterborne Fluids
Electrostatically
The PRO 5500wb spray gun is a 60 kV electrostatic
spray gun that is designed to spray conductive, water-
borne, non-flammable fluids. When spraying water-
borne fluids electrostatically, the gun must be con-
nected to a voltage isolation system, which isolates the
fluid supply from ground and allows voltage to be
maintained at the tip of the gun. For information on the
2
Graco H O PRO Voltage Block System, contact your
Graco distributor.
A safe, well designed voltage isolation system should
have the following features:
D All components of the isolation system that are
charged to high voltage must be contained within a
fence or enclosure that prohibits personnel from
making contact with the high voltage components
before the system voltage is discharged.
D A means for automatically discharging the system
voltage if someone opens the fence or enclosure or
enters the spray area.
D A bleed resistor to drain off the system voltage
when the spray gun is not in use.
D The system should not have any severe arcing
occurring when the isolation mechanism opens and
closes. Severe arcing will shorten the life of the
system components.
CAUTION
The Graco warranty is void if the spray gun is con-
nected to a non-Graco voltage isolation system or if
the gun is operated above 60 kV.
When connected to a voltage isolation system, all of
the fluid in the spray gun, fluid hose, and isolated fluid
supply are charged to high voltage, which means that
the system has more electrical energy than a solvent-
based system. Therefore, only non-flammable fluids
(defined on the front cover of this manual) can be
sprayed with the system or be used to clean, flush, or
purge the system.
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Introduction

Precautions must be taken when using electrostatic
waterborne equipment to avoid potential shock haz-
ards. When the spray gun charges the isolated fluid to
high voltage, it is similar to charging a capacitor or
battery. The system will store some of the energy while
spraying and retain some of that energy after the spray
gun is shut off. It is not safe to touch the front end of
the gun until the stored energy is discharged. The
amount of time it takes to discharge the energy de-
pends on the system design. Follow the Fluid Voltage
Discharge and Grounding Procedure, page 19,
before approaching the front of the gun.
Operating the Spray Function
Applying a minimum of 50 psi (345 kPa, 3.5 bar) air
pressure to the gun manifold's cylinder air fitting (which
is marked "CYL", see page 7) will retract the gun
piston, which opens the air valves and a short time
later opens the fluid needle. This provides 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
(Refer to page 7)
To operate the electrostatics, air pressure is applied to
the gun manifold's turbine air fitting (which is marked
"TA") through a Graco electrically conductive air hose.
The air enters the manifold and is directed to the inlet
of the power supply turbine (G). The air spins the
turbine, which then provides electrical power to the
internal high voltage power supply (H). The fluid is
charged by the spray gun electrode (J). The charged
fluid is attracted to the nearest grounded object, wrap-
ping around and evenly coating all surfaces.
The turbine air is exhausted into the shroud (D) and
out the back of the manifold through the fitting marked
"EXH", unless you are using part no. 238091 spray
gun, then the air is exhausted out of the slot in the
bottom of the shroud. The exhaust air helps keep
contaminants out and helps keep the gun clean.