TP-6137 5/03
53
Section 9 Generator Troubleshooting
9.4 Rotor Test
The two-pole rotor creates the magnetic field needed to
raise the alternating current in the stator windings.
Before testing, inspect the rotor for visible damage to the
pole shoes, insulation, and exposed coil windings.
Check the rotor bearings for noisy operation, excessive
wear, and heat discoloration. Replace or repair these
components if any of the above conditions exist.
Procedure to test the rotor’s insulation.
1. Disconnect the two rotor field diodes (D4 and D5).
See the wiring diagrams in Section 11.
2. Using a Megger set at 500 volts DC, check the
winding insulation resistance value to ground.
Check every part isolated from the others. See
Figure 9-2 Normally, windings with a resistance
value to ground greater than 1 MOhm are
considered good.
If resistance is lower than 1
MOhm, replace the rotor.
Figure 9-2
Rotor Insulation Test
Procedure to test the rotor’s continuity.
1. Using an Ohmmeter test, check if the rotor winding
is opened.
See Figure 9-3.
If an accurate
ohmmeter is not available, check the circuit’s
continuity using a 12 VDC battery and a suitable
lamp. See Figure 9-4. Replace the rotor if it is
grounded, has an opened or short circuit.
Figure 9-3
Rotor Continuity Test with Ohmmeter
Figure 9-4
Rotor Continuity Test with AC Test Lamp
Summary of Contents for 3.5EFOZ
Page 1: ...Marine Generator Sets Includes Engine Maintenance Models 4EOZ 3 5EFOZ TP 6137 5 03 Service ...
Page 10: ...TP 6137 5 03 VI Safety Precautions and Instructions Notes ...
Page 12: ...TP 6137 5 03 ii Service Assistance Notes ...
Page 28: ...TP 6137 5 03 16 Section 3 Scheduled Maintenance Notes ...
Page 42: ...TP 6137 5 03 30 Section 5 Fuel System Notes ...
Page 48: ...TP 6137 5 03 36 Section 6 Cooling System Notes ...
Page 102: ...TP 6137 5 03 90 Section 10 Generator and Engine Disassembly Reassembly Notes ...
Page 104: ...TP 6137 5 03 92 Section 11 Wiring Diagrams 11 1 Wiring Diagram Schematic GM20645 B ...
Page 105: ...TP 6137 5 03 93 Section 11 Wiring Diagrams 11 2 Wiring Diagram Point to Point GM20645 B ...
Page 106: ...TP 6137 5 03 94 Section 11 Wiring Diagrams Notes ...
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