What Does an Alternator Do in a Car?

One of the most important aspects of any vehicle is the alternator, responsible for turning the mechanical energy of the wheel’s rotations into electrical energy which is used by the battery to power the car’s various systems. Within the alternator, two parts called a stator and rotor act as an electromagnetic generator with a spinning flywheel core and coils of copper wire. The alternator sends current through a voltage regulator, which makes sure a stable and appropriate amount of current is sent out into various sub-systems of the car, like the speakers, AC, and battery.

Sometimes, an alternator will suffer damage or go out on its own and need to be replaced. Other times, people choose to upgrade to a high output alternator due to their various needs or customizations. These are able to output a higher amount of charge, which is necessary for high-performance, racing, or custom/modified vehicles.

How Do Alternators Work?

Within the engine, the drive belt is attached through a series of belts and pulleys to the alternator. As the engine turns, the belts turn the inner magnetic core of the alternator, which causes electrons to flow through the copper wires. This rotation is the core principle behind steam and nuclear power - heating water until the steam is powerful enough to turn flywheels which rotate the same type of device.

In essence, an alternator is just a miniature version of the power plants that give us our lights, cool our refrigerators, power our fans, and make all the things we love doing possible. Without this technology, many facets of modern life would disappear, and cars would cease to be as convenient as they currently are.

However, the alternator produces A/C power, but the car's systems use D/C power. This means that the current has to be changed, or rectified. A small device called a rectifier performs this function, changing the current into a form that can be used by the car. A rectifier uses diodes, which only let current flow in one direction.

From there, the current goes into the battery to keep it charged and functioning. The car draws power where needed for various accessories, and the system works efficiently and effectively at providing all the power a car could need.

What Do High Output Alternators Do?

The main reason people upgrade their alternators is that certain upgrades like sub speakers, lifts, or LED lights require more energy than a standard alternator can put out. Upgrading your alternator can help you save on fuel, and will ensure a more reliable battery charge. If you’re experiencing frequent stalling or trouble starting your vehicle, dim headlights, or malfunctioning accessories, the alternator is a good place to start looking.

Because of their more robust nature and construction, high output alternators are able to put out a higher level of voltage than a standard one. While you don’t have to worry about the car itself, as the voltage regulator will prevent current that is too high from flowing out, the charge wires and ground strap may need to be upgraded. This is because the higher charge can occasionally cause issues with burning out or overloading normal wires.

If you have been hearing strange noises like a high-pitched humming noise or experiencing frequent stalling and dead batteries it’s worth looking into your alternator. To test it, simply use a multimeter or voltmeter and touch the prongs to the terminals when the car is off and look for a reading of around 12-13 volts. Test it again when the car is running, and look for a reading of around 13-14.

This differential tells you that the alternator is working and putting out current. If your readings are much different than these, it’s a good idea to have your alternator checked out and consider an upgrade.

Alternators: A Key Part of the World Today

Imagine a world without alternators: car batteries piling up by the millions, cars constantly dying, and cars that don’t start without frequent new batteries. Indeed, without the alternator, the car itself might not even be possible. Alternators are an underappreciated and critical component to maintaining your vehicle at its highest level, so never overlook this part as a potential upgrade.

From Tesla, to Edison, to Ford, great electrical thinkers have shaped our world. The discovery that, essentially, rotating a magnet inside a coil of copper wires produces current revolutionized everything and shaped almost every facet of our world today. From there, it was a simple and logical step to simply attach an alternator to the drive shaft of a turning wheel, making the automobile as we know it possible.

What this meant for humanity was the ultimate freedom, and the greatest American pastime - driving. Driving allows us to transcend borders, make connections, and achieve our dreams. That would be difficult to do without an alternator, so always make sure that yours is working properly and contact a sales location today if you are having issues.

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