Getting to know alternators

This week in our “Getting to Know” series, we take a look at what an alternator is and how it works.


What is an alternator?


Formerly the job of a generator in older vehicles, the role of an alternator is to charge up the battery to power the starter motor, ignition and other electrical components on a car. It’s driven by the crankshaft.


Where can I find it?


The alternator can be found near to the front of the engine.


How does an alternator work?


Cylindrical in shape, the alternator is made of up of four core components. These are namely the stator, rotor, diode and voltage regulator. The rotor spins inside the stator, producing electricity, which is converted by the diode from an AC to DC current. This is subsequently used to charge the car’s battery. The voltage regulator makes sure the current flowing to the battery does not reach a level which is too high.


What happens if the charging voltage is too low?


If the voltage is too low, the charging system could fail which can cause the car to breakdown. This could be as a result of worn or loose cables.


Where can I find a garage to get my alternator repaired or replaced?


To find your local Motor Ombudsman-accredited franchised car dealership or independent garage to get your alternator repaired or replaced, visit The Motor Ombudsman’s online Garage Finder.


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