Alternator & Regulator - HITACHI: Description
Hitachi alternators are conventional 3-phase, self-rectifying alternators. Three positive and 3 negative diodes are used to rectify current. All models are equipped with Integrated Circuit (IC) voltage regulators.
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.