Alternator / Charging System

What is a Charging System?

The purpose of the charging system is to maintain the charge in the vehicle’s battery, and to provide the main source of electrical energy while the engine is running. Vehicle’s today are equipped with many electrical devices to drive safely and comfortably. Your vehicle requires electricity not only while driving but also while it stops. The vehicle has a battery for a power supply and a charging system to generate electricity by the engine running. The charging system supplies electricity to all the electrical devices and charges the battery.

The main component in the charging system is the ALTERNATOR. The alternator is a generator that produces Alternating Current (AC), similar to the electrical current in your home. This current is immediately converted to Direct Current (DC) inside the alternator. This is because all modern automobiles have a 12 volt, DC electrical system.

A voltage regulator “regulates” the charging voltage that the alternator produces, keeping it between 13.5 and 14.5 volts to protect the electrical components throughout the vehicle.

There is also a system to warn the driver if something is not right with the charging system. This is usually, a warning lamp but some vehicles have a charging system gauge. The lamp is often labeled “Bat” or “Alt.”. If this warning lamp lights up while the engine is running, it means that there is a problem in the charging system, usually an alternator that has stopped working.

The alternator is driven by a belt that is powered by the rotation of the engine. This belt goes around a pulley connected to the front of the engine’s crankshaft and is usually responsible for driving a number of other components including the water pump, power steering pump and air conditioning compressor.

Vehicles today require more power than those of 20 or 30 years ago. Computers, power windows and accessories, navigation systems, sound systems etc. all require electrical power. Alternators are required to produce more amperage.

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