Weld Control Feedback Test Procedure - Lincoln Electric RANGER 305G EFI Service Manual

LINCOLN ELECTRIC

WELD CONTROL FEEDBACK TEST PROCEDURE

Service and repair should be performed by only Lincoln Electric factory trained personnel. Unauthorized
repairs performed on this equipment may result in danger to the technician or machine operator and will
invalidate your factory warranty. For your safety and to avoid electrical shock, please observe all safety
notes and precautions detailed throughout this manual. If for any reason you do not understand the test
procedures or are unable to perform the test/repairs safely, contact the Lincoln Electric Service Department
for electrical troubleshooting assistance before you proceed. Call 1-888-935-3877.
TEST DESCRIPTION
This test will determine if the Weld Control Board is receiving accurate current and voltage feedback from
the Weld Circuit.
This test will only yield usable information if the machine is producing some weld output.
MATERIALS NEEDED
Digital Multimeter Suitable For Accurate Readings In Both The Millivolt And Normal Weld Voltage Ranges.
Resistive Load Bank
Ammeter, Suitable For Accurate Readings Of Normal Welding Current (often Built Into The Load Bank).
Wiring Diagram
TEST PROCEDURE
1. Turn off the engine on the Ranger 305G EFI machine.
2. Perform the Case Cover Removal Procedure.
3. Perform the Capacitor Discharge Procedure.
4. Place the idle switch in the "HIGH IDLE" position.
5. Place the mode switch in the "CC-STICK" position.
6. Place the weld terminals switch in the "WELD TERMINALS ON" position.
7. Make sure that nothing is plugged into either Amphenol receptacle.
8. Connect the resistive load bank and the ammeter to the weld output terminals per the equipment
manufacturer's instructions; also connect the voltmeter probes across the weld output terminals.
9. Start the machine and apply a load of about 200 amps, as shown on the external ammeter. If the
machine will not produce 200 amps apply as much load as you can.
10. Compare the readings shown on the external ammeter and voltmeter to the amps and volts
displayed on the front panel of the machine.
11. If the readings shown on the front panel displays are about the same or very close to the reading on
the external meters, the feedback is probably good and this test is complete.
12. If the readings differ significantly, continue with this procedure.
13. Turn off the engine and release the load from the weld terminals. The load bank and ammeter
should remain connected, but the load should be released.
14. Perform the Case Cover Removal Procedure.
Ranger® 305G EFI Service Manual
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