Most car owners think that it’s their battery that powers all things electric in your car, be it your headlights, windshield wipers, or the radio. However, it is your car’s alternators that produces most of your vehicle’s electricity.

The battery in your car is ideally used to ignition your vehicle and provide power when the engine is not running. The alternators is the most crucial component of your car’s charging system, so it would be best if you understand how it works if you have to deal with your vehicle not starting.

What is an alternators? 

An alternators is a generator whose primary function is to distribute electricity throughout your car and recharge its battery. Besides some hybrid models, all standard vehicles that feature an internal combustion engine will have an alternator.  

As big as a regular coconut, the alternator is usually mounted to the front of your vehicle’s engine and has a belt running around it. Since automotive batteries cannot fully meet the electrical system’s requirements for an extended time, your alternator’s job is to restore all the electrical power to the battery.  


The Best And #1 Alternators In Irving-Tx - Express Auto Shop
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The alternators also helps supply current to all the various electrical accessories in your vehicle when your engine is running. We have been using alternators in cars since the late 1960s when it first made an appearance in the Plymouth Valiant.  

Before they came into the picture, we used to depend on direct current (DC) generators. Both AC alternators and DC generators rely on a phenomenon known as electromagnetic induction. 

Electromagnetic induction 

This kind of induction occurs when electricity is created by shifting a conductor through a magnetic field. It could also happen if a magnetic field passes through a conductor.

In order to produce electricity using a direct current generator, a conductor is rotated, and its field is held. In an alternator, however, the conductor is held in its place while the field rotates.

Even though they may sound very much the same, generators could not produce the required amount of current to power the various number of electrical accessories that we have in our modern-day vehicles. This is the reason why we dropped DC generators in favor of the alternator.

The stator, rotor, and diodes  

Semiconductors’ arrival is the main reason for creating various devices we use daily, from a transistor radio to the home computer. An alternator is one of such devices that relies on a specific type of semiconductor called a diode.

The diode allows current to only pass in one direction and not the other. This helps in converting an alternate current voltage into a direct current, which our vehicles can use. An alternator was specifically created to convert mechanical energy into electrical energy.

It is driven by the energy which is created by a belt. The belt is used to turn a pulley, which is further attached to your rotor shaft.

A rotor is a magnetic iron core that is wrapped with a coil of wire. Both the coil ends are connected to a copper slip ring that is then attached to brushes.

One brush is attached to the ground while the other to the field terminal in your voltage regulator. Spinning the belt results in turning the router, which is placed inside the stator. Since a rotor is a magnet and a stator is a conductor, rotating the router creates electricity in your stator. This is induction at work.

Ideally, three coils of wire are wrapped inside the stator, each generating its alternating current voltage. This voltage needs to be converted into direct current before using it to charge the vehicle’s battery and power all the various electrical accessories. This is the primary purpose of diodes inside the rectifier bridge.

As mentioned earlier, diodes are solid-state semiconductors used to allow current to pass in a particular direction. The diode helps block the negative output from all of your stator coils so that only positive voltage can reach your vehicle.

Voltage regulators 

Another important feature that an alternator requires is a voltage regulator. The alternators requires a voltage regulator to control the overall output of electricity.

The regulator switches the router circuit control on and off to get this task done correctly, which reduces its magnetic field. This helps in reducing the overall voltage that enters the stator, as is the total alternator output.

Old generation alternators used a regulator that was either internal to the alternators or an externally mounted regulator. These could be either electronically or mechanically controlled. In our new age vehicles, voltage regulation is the PCM’s primary responsibility (powertrain control module).

We no longer need a separate regulator. Ideally, the powertrain control module monitors the engine speed, battery temperature, and battery voltage. It then pulses the field coil of the alternator to control its output.

Charge indicators 

Warning lights and gauges are built to alert the driver if there is an issue with the charging system. Older vehicles used ammeters for this, whereas modern vehicles use warning lights or voltmeters.

However, voltmeters are known to be inaccurate, which is the reason why most vehicle manufacturers have now shifted to warning lights.

Besides being accurate, if your vehicle’s charging system has a problem, the indicator will still receive ground from the regulator, keeping it illuminated.

If you have a problem with your vehicle’s alternator, you need to get it checked immediately.

Get in touch with Express Auto & Tires today! 

Serving Irving, TX, Express Auto & Tires is a trusted auto service provider specializing in auto repairs, and can handle any job type. By now, you should know that an alternator is an essential part of your vehicle.

Without it, your vehicle will not stay running for long. Hopefully, now you have a little knowledge of how your alternator works and why you need to get it fixed as soon as possible.

Our capable staff can perform auto inspections and service replacements without any hassle and will have your vehicle back on the road. In addition to Irving, we also serve Euless and Grand Prairie.


Call us today at 972-636-4903, and one of our experts will take care of all your servicing needs.

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