Ransburg RMA Indirect A12869 - Manual (Page 45)

RMA-303 Indirect Charge - Operation
LN-9268-11.4 40
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W A R N I N G
! W A R N I N G
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W A R N I N G
> Danger of shock and/or personal injury can
occur. Proper grounding procedures must be
followed. Personnel must never work around
the turbine when the turbine is spinning or
when high voltage is turned on.
FLUID VALVE CONTROL
(Trigger, Dump, and Solvent)
(See "Figure 2 - Circuit Diagram" in the "Intro-
duction" section.) The fluid valves in the RMA
-303 are actuated by an air signal. The air
pressure must be greater than 70 psi (482.6
kPa) to assure proper actuation of the valve.
Applying air to the valve actuator turns on the
fluid or air for that valve.
The paint trigger valve controls the paint flow
to the bell. When actuated, paint flows
through the valve to the fluid tube, and into the
rear of the bell cup. The bell cup must be
spinning at least 30,000 rpm when fluid is
turned on to enable the fluid to flow through
the bell paint passage and be atomized.
The dump valve controls the paint flow
through the dump line. When actuated, paint
flow is directed to the dump return line. This
provides a method of rapidly removing paint
from the incoming line for cleaning and/or col-
or change. Normally, the dump valve is not
actuated at the same time as the paint trigger
valve since the trigger valve is intended to
cause the fluid to flow to the bell at the pre-
scribed input pressure.
The solvent valve controls the flow of cup
wash solvent. When actuated, solvent flows
through a separate fluid tube passage and into
the bell cup . This provides cleaning of the
inside of the bell cup. The outside of the cup
is simultaneously cleaned by a nozzle mount-
ed on the shaping air ring and shroud. The
solvent valve should never be triggered at the
same time as the paint trigger valve to prevent
solvent from flowing backward into the paint
line.
The cup wash air valve controls the flow of air.
It is recommended that this valve and the sol-
vent valve be controlled to create an air/
solvent chop sequence for superior internal
and external cup cleaning.
> Never perform the interior/exterior cup clean
process with high voltage on (direct charge
only).
To color change the applicator, a solvent/air
chop must be provided through the main paint
line. (See "Figure 5 - Typical Installation" in
the "Installation" section.)
> The normal fluid flow range is 25-700 cc/
min. During a color change or when flushing
the system, higher flow rates may be required.
However, the maximum flow rate through the
bell cup must not exceed 700 cc/min. to avoid
solvent or paint from flooding into the internal
portion of the air bearing motor assembly or
front shroud.