Ransburg MMA-570 Direct_Ind Charge Atomizer A13366 - Manual (Page 80)

TROUBLESHOOTING GUIDE - DIRECT CHARGE
(Cont.)
Faulty low voltage connections
(Usually indicated by MicroPak.
feedback fault light)
Faulty high voltage connection
MicroPak or cascade failure
Improper color change (i.e., paint or
solvent in dump line)
Low or no high voltage
Poor grounding of parts being coated
Excessive turbine speed
Excessive inner/outer shaping air
Excessive target distance
Turbine drive air not present
Bearing air return signal not present
Brake air is activated
Make sure quick disconnect electrical
connection is aligned and clean.
a. Check low voltage connection at cascade.
Remove cascade and check continuity
between cascade connection and turbine
shaft.
Refer to “MicroPak” service manual for
detailed “Troubleshooting Guide”.
Optimize color change.
Verify high voltage at bell cup edge. Nor-
mallya high voltage setting of 70-100 kV is
appropriate for most applications.
Verify that parts being coated are properly
grounded (the electrical resistance between
the part and ground must not exceed 1
megohm).
For optimum transfer efficiency and spray
pattern control, the bell rotational speed
should be set at the minimum required to
achieve proper atomization of the coating
material.
Shaping air should be set at the minimum
air volume required to gently direct the
spray pattern toward the part being coated.
Excessive shaping air will cause some
atomized particles to “blow-by” the part or
bounce back onto the atomizer.
The recommended target distance is be-
tween 6-12 inches (152.4-304.8 Nm) (see
“Target Distance” in the “Operation” section
of this manual).
Verify supply air pressure.
a. Verify bearing air return signal.
b. Increase bearing air supply pressure to
90 psig (± 10 psig) (620.5 ± 68.9 kPa).
Remove brake air signal (turbine air and
brake air must be interlocked to prevent
both from being used simultaneously).
General Problem Possible Cause Solution
Low or No High
Voltage (Cont.)
Low Transfer
Efficiency (or light
coverage)
No Turbine Air
MMA-570 Direct/Indirect Charge - Maintenance
Ransburg
LN-9279-13 77