Electrical
Electrical
Electrical Tests
Tests
Tests
Electrical components inside the gun affect
performance and safety. Use the following
procedures to test the condition of the power supply
and gun body, and electrical continuity between
components.
Use megohmmeter Part No. 241079 (AA) and an
applied voltage of 500 V. Connect the leads as
shown.
Megohmmeter Part No. 241079 is not approved
for use in a hazardous area. (In Figure 15, item
AA.) To reduce the risk of sparking, do not use
the megohmmeter to check electrical grounding
unless:
• The gun has been removed from the hazardous
area;
• Or all spraying devices in the hazardous area
are turned off, ventilation fans in the hazardous
area are operating, and there are no flammable
vapors in the area (such as open solvent
containers or fumes from spraying).
Failure to follow this warning could cause fire,
explosion, and electric shock and result in serious
injury and property damage.
Test
Test
Test Gun
Gun
Gun Resistance
Resistance
Resistance
1.
Follow the steps under
Prepare the Gun for Service, page 48
2.
Trigger the gun and measure resistance
between the electrode needle tip (3) and the
air swivel (21). The resistance should be
104–150 megohms (90–120 megohms for
Model L60M19). If outside this range, go to
Test Power Supply Resistance, page 39
If in range, see
Voltage Loss Troubleshooting, page 41
for other
possible causes of poor performance, or contact
your Graco distributor.
Figure 15 Test Gun Resistance
Test
Test
Test Power
Power
Power Supply
Supply
Supply Resistance
Resistance
Resistance
1.
Follow the steps under
Prepare the Gun for Service, page 48
2.
Remove the power supply (11). Follow the steps
in
Power Supply Removal and Replacement,
.
3.
Remove the turbine alternator (15) from the
power supply.
4.
Measure resistance from the power supply's
ground strips (EE) to the spring (11a). The
resistance should be 90–115 megohms. If
outside this range, replace the power supply. If in
range, go to
Test Electrode Resistance, page 40
.
3A7504A
39