Graco PRO Auto Xs Instructions-Parts List Manual page 34

Troubleshooting
Visual Check
First, check the system for any visible faults or errors to
help isolate whether the spray gun, fluid hose or voltage
isolation system has failed. A voltage probe and meter,
part no. 236003, is helpful for diagnosing voltage prob-
lems and is required for some of the troubleshooting
tests that follow.
1. Check that all of the air and fluid tubes and hoses
are properly connected.
2. Check that the voltage isolation system valves and
controls are properly set for operation.
3. Check that the spray gun and voltage isolation sys-
tem have sufficient air pressure.
4. Check that the gun turbine air (TA) is turned on and
the pressure is set correctly.
5. Check that the voltage isolation system's enclosure
door is closed and that any safety interlocks are
engaged and working properly.
6. Make sure the voltage isolation system is in the "iso-
late" mode, where it is isolating the fluid voltage
from ground.
7. To eliminate air gaps in the fluid column, spray
enough fluid to purge the air out between the volt-
age isolation system and the spray gun. An air gap
in the fluid hose can break the electrical continuity
between the spray gun and the isolated fluid supply
and cause a low voltage reading on a voltage meter
connected to the isolated fluid supply.
8. Check the spray gun cover and barrel for accumu-
lated overspray. Excessive overspray can create a
conductive path back to the grounded gun. Install a
new gun cover and clean the exterior of the gun.
9. Inspect the entire system for any visible fluid leak-
age and repair any fluid leaks that are found. Pay
special attention to the following areas:
• Packing area of the spray gun
• Fluid hose: check for leakage or any bulges in
the outer cover, which may indicate an internal
leak
• Internal voltage isolation system components
34
Tests
If you still have no voltage, separate the spray gun and
hose from the voltage isolation system and check
whether the gun and hose alone will hold voltage with
the following test.
1. Flush the system with water and leave the lines
filled with water.
2. Discharge the system voltage (page 21).
3. Relieve the pressure (page 21).
4. Disconnect the fluid hose from the voltage isolation
system.
Avoid allowing any water to leak out of the fluid hose
as that could cause a significant air gap in the fluid
column up to the gun electrode, which can break the
conductivity path and conceal a potential failure
area.
5. Position the end of the hose as far as possible away
from any grounded surface. The end of the hose
must be at least 1 ft. (0.3 m) from any ground. Make
sure that no one is within 3 ft. (0.9 m) of the end of
the hose.
6. Turn the turbine air to the gun on. Measure the volt-
age at the gun electrode with a voltage probe and
meter.
7. Discharge the system voltage by waiting 30 sec-
onds and then touching the gun electrode with a
grounded rod.
8. If the meter reading is 45 to 55 kV, the gun and fluid
hose are okay, and the problem is in the voltage iso-
lation system.
If the reading is below 45 kV, the problem is in the
gun or fluid hose.
9. Flush the fluid hose and gun with enough air to dry
out the fluid passages.
10. Turn the turbine air to the gun on. Measure the volt-
age at the gun electrode with a voltage probe and
meter.
309457G