Rotor Resistance And Ground Test Procedure (Static) - Lincoln Electric Fleet 650 Service Manual

LINCOLN ELECTRIC

ROTOR RESISTANCE AND GROUND TEST PROCEDURE (STATIC)

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 Rotor Winding is open, shorted or grounded.
MATERIALS NEEDED
Volt/Ohmmeter
Wiring Diagram
TEST PROCEDURE
1. Turn off the engine on the Fleet 650 machine.
2. Perform the Case Cover Removal Procedure.
3. Perform the Chopper Module Capacitor Discharge Procedure.
4. Label and disconnect leads 201 and 200B from the field capacitor located on the right side of the
PCB bracket. See Figure F.9. See Wiring Diagram. This will electrically isolate the rotor windings.
5. Using the volt/ohmmeter, measure the resistance from lead 201 to 200B.
approximately 28 ohms. See Figure F.9. See Wiring Diagram.
6. If reading is incorrect, remove the brush holder bracket and measure directly across the slip rings. If
reading is correct, check the brushes and the leads. If reading is still incorrect, the rotor is defective.
7. Measure the resistance to ground from either of the slip rings to any good unpainted chassis
ground. The resistance should be very high, at least 500,000 ohms (500k).
8. If the test does not meet the resistance specifications, then the rotor is grounded and should be
replaced.
9. If this test meets the resistance specifications, continue testing using the Rotor Resistance and
Ground Test Procedure (Dynamic).
10. Re-connect leads 201 and 200B to the field capacitor. Be sure to connect them to the proper
polarity terminals. See Figure F.9. See Wiring Diagram.
11. Perform the Case Cover Replacement Procedure.
Fleet™ 650 Service Manual
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