Rotor Voltage Test Procedure - Lincoln Electric Fleet 650 Service Manual

LINCOLN ELECTRIC

ROTOR VOLTAGE 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 Rotor Winding is functioning properly.
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. Connect the voltmeter probes to the field capacitor terminals (201 & 200B). See Wiring Diagram.
5. Set the 'RUN/STOP' switch to the 'RUN' position. Start the engine and allow the RPM to stabilize for
about 15 to 30 seconds. The meter should read 145-175 VDC.
6. Set the 'RUN/STOP' switch to the 'STOP' position.
7. If the meter reading is normal, this test is complete.
8. If the voltage measures zero or very near zero, the rotor flashing circuit may be faulty, the leads may
be open or the rotor may be shorted. Check the flashing resistor (R1 10 ohm). See Wiring Diagram.
9. Perform the Rotor Resistance and Ground Test Procedures (Static) and (Dynamic) and the Flashing
Voltage Test Procedure (Engine Not Running).
10. If voltage is higher than 175 VDC, the engine RPM may be too high or there may be voltage intrusion
from one of the higher voltage stator windings to the stator exciter winding.
11. If the voltage is lower than 145 VDC, the engine RPM may be too low or there may be problems in
the windings, capacitor or other exciter circuit components or connections.
12. If the meter reading indicates battery voltage, about 12 to 14 VDC, the rotor may be open or the
brushes may be faulty or not making proper contact with the slip rings.
13. If the voltage measures about 3 to 5 VDC, the generator is not building-up to normal output even
though the flashing circuit appears to be functioning normally.
14. Perform the Flashing Diode (D1) & Field Diode (D2) Test Procedure.
15. Perform the Case Cover Replacement Procedure.
Fleet™ 650 Service Manual
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