Generator Inspection
Generator InspectionRotor
1. Using an ohmmeter, check for continuity between slip rings of rotor (1). If there is no continuity, replace the rotor.
Standard resistance between slip rings of rotor: About 2.9 Ohm at 20 °C (68 °F)
2. Using an ohmmeter, check that there is no continuity between slip ring and rotor (1). If there is continuity, replace the rotor.
3. Check slip rings for roughness or scoring. If rough or scored, replace the rotor.
Using a vernier caliper, measure the slip ring diameter. If the diameter is less than minimum, replace the rotor.
Slip ring diameter
Standard: 14.4 mm (0.567 in.)
Limit: 14.0 mm (0.551 in.)
Stator
1. Using an ohmmeter, check all leads for continuity. If there is no continuity, replace the stator.
2. Using an ohmmeter, check that there is no continuity between coil leads and stator core. If there is continuity, replace the stator.
Brush and Brush Holder
Check each brush for wear by measuring its length as shown. If the brush is found worn down to service limit, replace the brush.
Exposed brush length "a"
Standard: 10.5 mm (0.41 in.)
Limit: 4.5 mm (0.18 in.)
Rectifier
1. Using an ohmmeter, connect one tester probe to the "B" terminal (1) and the other to each rectifier terminal (2).
2. Reverse the polarity of the tester probes and repeat step (1).
3. Check that one shows continuity and the other shows no continuity. If there is continuity, replace the rectifier.
4. Using an ohmmeter, connect one tester probe to each negative terminal (1) and the other to each rectifier terminal (2).
5. Reverse the polarity of the tester probes and repeat step 4).
6. Check that one shows continuity and the other shows no continuity. If there is continuity, replace the rectifier.