Alternator & Regulator - BOSCH: Description

Bosch alternators are conventional 3-phase, self-rectifying type alternators. Bosch 55 through 75 amp alternators use 6 diodes (3 positive and 3 negative) connected to stator windings to rectify current. Bosch 80 and 90 amp alternators use 14 diodes, instead of 6.

All alternators use 3 exciter diodes connected to stator windings. These diodes turn off the alternator indicator light and supply power to the voltage regulator while the engine is running. Bosch regulators are transistorized solid state and integral with alternator.