Troubleshooting

Troubleshooting

Voltage Loss 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 service this equipment unless you are trained and qualified.

Follow the Fluid Voltage Discharge and Ground- ing Procedure on page 16 before checking or servicing the system and whenever you are instructed to discharge the voltage to ensure the voltage is discharged and avoid serious injury from an electric shock.

Spray Gun WARNING

PRESSURIZED EQUIPMENT HAZARD

To reduce the risk of an injury, follow the Pressure Relief Procedure on page 16 before checking or servicing any part of the system and whenever you are instructed to relieve the pressure.

Voltage Loss Troubleshooting

Normal spraying voltage for a system using the PRO 3500wb gun is 45 to 55 kV. The system voltage is lower due to spraying current demands and voltage isolation system losses.

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

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

Spray Gun

DFluid leakage

DDielectric breakdown at the fluid hose connection or fluid packings

DNot enough air pressure for the turbine

DFaulty power supply

DExcessive overspray on gun surfaces

DFluid in the air passages

Waterborne Fluid Hose

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

DAir gap in the fluid column between the gun and isolated fluid supply, causing a low voltage reading on the isolation system voltage meter.

Voltage Block

DFluid leakage

DDielectric breakdown of hoses, seals, or connec- tions

DIsolators not functioning properly

Visual Check

First, check the system for any visible faults or errors to help isolate whether the spray gun, fluid hose or voltage block has failed. A voltage probe and meter, part no. 236003, is helpful for diagnosing voltage problems and is required for some of the troubleshoot- ing 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. Refer to the voltage isolation system manual.

3.Check that the spray gun and voltage isolation system have sufficient air pressure.

4.Check that the gun ES ON-OFF lever is in the ON position and that the gun ES indicator light comes on. If the ES indicator light does not come on, remove the spray gun for service, and complete the electrical tests on page 28.

5.Check that the voltage isolation system’s enclo- sure door or safety fence gate is closed and that any safety interlocks are engaged and working properly.

6.Make sure the voltage isolation system is in the “isolate” mode, where it is isolating the fluid volt- age from ground.

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Graco Inc 308584, 3500WB Voltage Loss Troubleshooting, Spray Gun, Waterborne Fluid Hose, Voltage Block, Visual Check