Generator — Checking Elements

Rotor

1. Check the field winding for electrical conductivity. Make sure there is continuity between the slip rings. If the resistance is very low, this indicates a short circuit (pic. 7.3). If there is no electrical conductivity or a short circuit, the rotor must be replaced. Resistance: approximately 2-5 ohms.



2. Check the field winding for a short to ground (pic. 7.4). Make sure there is no electrical conductivity between the slip rings and the core. Otherwise, the rotor must be replaced.

Stator

3. Check the electrical conductivity of the winding wires (pic. 7.5). If there is no electrical conductivity, the stator should be replaced.




4. Check the contact of the stator winding with the housing (pic. 7.6). Make sure there is no electrical conductivity between the winding wire and the core. If present, the stator and rectifier should be replaced.

Rectifier

1. Using an ohmmeter, check the continuity between the positive rectifier and the stator winding wire connection terminal. If there is continuity in both directions, the diode has shorted. In this case, the rectifier must be replaced (pic. 7.7).




2. Using an ohmmeter, check the continuity between the negative rectifier and the stator winding wire connection terminal. If there is continuity in both directions, the diode has shorted. In this case, the rectifier must be replaced (pic. 7.8).



3. Use an ammeter to check the continuity of each of the three diodes at both ends. If there is no electrical conductivity in both directions, the diode under test has short circuited. In this case, the heat sink changes (pic. 7.9).



4. Brushes that are worn out more than allowed must be replaced (pic. 7.10).




5. Connecting harnesses are soldered, the old brush with a spring is removed (pic. 7.11).



6. A new brush is installed in the brush holder and then the wire is soldered (pic. 7.12).