11. A dielectric breakdown is most likely in one of
the following three areas. Repair or replace the
component that is failing.
a.
Fluid hose:
• Check for leakage or any bulges in the
outer cover, which may indicate a pin-hole
leak through the PTFE layer. Disconnect
the fluid hose from the gun, and look for
signs of fluid contamination on the outside
of the PTFE portion of the fluid tube.
• Inspect the end of the hose connected to
the voltage isolation system. Look for cuts
or nicks.
• Make sure the hose is properly stripped
(see
Connect the Waterborne Fluid Hose,
). Restrip or replace the hose.
b.
Fluid packings:
Remove the packing assembly from the gun
(see
Fluid Packing Rod Removal, page 53
),
and look for signs of fluid leakage or any
blackened areas, which would indicate arcing
is occurring along the packing rod.
c.
Fluid hose connection to the spray gun:
A breakdown at the fluid hose connection
joint would be caused by fluid leaking past
the o-ring seals on the end of the hose.
Remove the hose at the gun connection and
look for signs of fluid leakage along the PTFE
tube.
12. Before reassembling the gun, clean and dry the
gun fluid inlet tube. Repack the inner spacer of
the fluid packing rod with dielectric grease and
reassemble the gun.
13. Reconnect the fluid hose.
14. Check the gun voltage with the voltage probe
and meter before filling the gun with fluid.
3A7504A
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