Troubleshooting

Troubleshooting

WARNING

Electric Shock Hazard

Installing and servicing this equipment requires access to parts which may cause an electric shock or other serious injury if

the work is not performed properly. Do not install or repair this equipment unless you are trained and qualified.

Follow the Fluid Voltage Discharge and Grounding Procedure on page 20 before checking or servicing the system and whenever you are instructed to dis- charge the voltage.

WARNING

Pressurized Equipment Hazard

To reduce the risk of an injury, follow the Pressure Relief Procedure on page 20 before checking or servicing any part of the system and whenever you are instructed to relieve the pressure.

A loss of spraying voltage can be caused by a problem with the spray gun, fluid hose, or voltage isolation sys- tem, since all of the system components are electrically connected through the conductive, waterborne fluid.

Before troubleshooting or servicing the voltage isolation system itself, you need to determine which component in the system is most likely causing a problem. Possible causes include the following:

Spray Gun

Fluid leakage

Dielectric breakdown at the fluid hose connection or fluid packings

Not enough air pressure for the turbine

Faulty power supply

Excessive overspray on gun surfaces

Fluid in the air passages

Waterborne Fluid Hose

Dielectric failure of hose (pin-hole leak through PTFE layer)

Air gap in the fluid column between the gun and iso- lated fluid supply, causing a low voltage reading on the isolation system voltage meter.

Voltage Loss Troubleshooting

Normal spraying voltage for a system using the water- borne gun is 45-55 kV. The system voltage is lower due to spraying current demands and voltage isolation sys- tem losses.

Voltage Isolation System

Fluid leakage

Dirty interior

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HP GRACO OR PRO TI1681A manual Voltage Loss Troubleshooting, Spray Gun, Waterborne Fluid Hose, Voltage Isolation System