Dual purge spraying, Turbine speed, Ransburg – Ransburg RMA-560 Single_Dual Purge Direct A13364 User Manual
Page 38

(See “Circuit Diagram” in the “Introduction” sec-
tion.) The fluid valves in the RMA-560 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 color 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 prescribed 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 mounted 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.
To color change the applicator, a solvent air chop
must be provided through the main paint line (see
”Typical Installation RMA-560” in the Installation”
section).
TURBINE SPEED
Turbine speed is determined by the input air
pressure/flow at the rear of the atomizer.
Turbine speed is intended to be closed loop
controlled using the fiber optic speed transmitter,
located on the turbine manifold. A speed input
to a remote speed controller, such as the Serial
Atomizer Module, is required. (See “Speed and
Pressure” charts in the “Introduction” section.)
DUAL PURGE SPRAYING
The RMA-560 has dual purge capability. This
means the applicator can continue to spray paint,
at voltage, while side “B” or “Paint 2” is being
flushed or cleaned. To operate in the dual purge
mode,
two (2) separate color valve systems
must be installed.
NOTE
C A U T I O N
!
The bell rotational speed determines
the quality of atomization and can be
varied for various paint flow rates and
paint formulations. For optimum transfer
efficiency and spray pattern control, the
bell rotational speed should be set at the
minimum required to achieve proper at-
omization.
Excessive speed reduces
transfer efficiency!
The normal fluid flow range is 25-800 cc/
min. During a color change or when flushing
the system, high flow rates may be required.
However, the maximum flow rate through
the bell cup must not exceed 800 cc/min.,
to avoid solvent or paint from flooding into
the internal portion of the air bearing motor
assembly or front shroud.
High voltage must be interlocked
with the solvent valve to prevent solvent
spraying while high voltage is on.
Never perform the interior/exterior
cup clean process with high voltage on.
W A R N I N G
!
RMA-560 Single/Dual Purge Direct Charge - Operation
Ransburg
LN-9278-13
35