How does an alternator work?

Most people think of the battery as the driving force for powering your vehicle's electronics, but that's only part of the equation. The charging system is a combination of your battery, voltage regulator, and alternator. Today, our focus is on the alternator.

The alternator gets its power from the serpentine belt, which gets its power from the engine's crankshaft. The alternator got its name because it uses alternating current. The alternator's job is to channel that alternating current (AC) to the battery to get the voltage needed to power the electronics in your car. Essentially, the alternator takes mechanical energy from the engine and turns it into electrical power for your vehicle's accessories.

The alternator acts as a generator. In a very cool process, the alternator creates AC power through electromagnetism that is created from the rotor and converted by the stator. The conductor inside is held stationary and the field is rotated to create the electricity. The alternator's various components all serve the job of providing the right type and amount of power to your car.

Because an alternator (AC) and car battery (DC) use different current directions, the electricity's converted via the diode rectifier that lies within the alternator. This process is what gives the alternator the ability to charge your battery.

A failing alternator will drain a good battery, dim your lights, make it hard for your car to start, and more. Like most parts, the alternator will lose juice over time, and there may be a need for replacement. For a battery or alternator diagnostic, call Ferber's Tire and Auto Service!