An alternator is a maintenance-free yet the most important unit of the car’s engine. It generates electricity, provides electrical supply to vehicles, and recharges the battery. The alternator works by converting mechanical energy into electrical energy from alternating current to the direct current.
The primary function is to work jointly with the battery to supply energy to the electrical components, i.e., lights, fan, windshield wipers, etc. It changes the alternating current into a direct current and regulates the voltage to meet the required minimum power for each unit.
This is a three-wire alternating wiring diagram showing the connections between the different components. The circuit comprises three main wires: battery positive cable, voltage sensing wire, and ignition wire. The ignition input wire is attached to the engine. It conducts electricity from the engine to the alternator while the voltage detecting cable senses the voltage and is connected to the rectifier.
Using a three-wire alternator ensures regulated voltage for all components. Such alternators are multi-purposed and have built-in voltage rectifiers for power sensing. Unlike the one-wire alternators, they can generate and rectify electricity in one circuit.