Alternator & Regulator - HITACHI: Description

Hitachi alternators are conventional 3-phase, self-rectifying alternators. Six diodes (3 positive and 3 negative) are used to rectify current. Most models are equipped with Integrated Circuit (IC) voltage regulators, except Isuzu gasoline engine equipped models.

The IC voltage regulator consists of integrated circuits using transistors. These transistors control current flow to alternator rotor, thus maintaining alternator output voltage at a constant value.

On the charge indicator light circuit, a diode monitors alternating voltage at the stator. When monitored voltage and charging voltage are equal, the charge indicator light is turned off.

Fig 1: Exploded View of Typical Hitachi Alternator