Alternator & Regulator: Description

NOTE: Some Volvos are equipped with a Nippondenso generator. Testing information on these generators is not available from the manufacturer.

Bosch generators are a conventional 3-phase, self-rectifying type. Bosch 55-amp through 75-amp generators have 3 positive and 3 negative diodes connected to stator windings to rectify current. Bosch 80-amp through 120 amp generators have 14 diodes. All generators use 3 exciter diodes connected to stator windings. These diodes turn off the generator indicator light and supply power to voltage regulator while engine is running. Voltage regulator is transistorized.