When and how to change alternators in a car? - The Bromsgrove Standard

When and how to change alternators in a car?

Bromsgrove Editorial 17th May, 2023   0

By definition, an alternator is a device that converts mechanical energy into alternating current electrical energy.

The alternator is the primary source of electrical power. As the alternator rotates, it generates voltage, which in turn charges the vehicle’s battery. In addition, the alternator also powers all the vehicle’s electrical systems.

The alternator performs its primary function only by transferring mechanical energy from the rotation of the motor shaft to the rotor.

The magnetic field resulting from the rotation of the rotor is converted into an electric current in the starter coil and then distributed to the main consumers in the on-board network.

This allows the power to be used only during the start-up phase, after which the battery charge is gradually restored.

Without this important device, the battery would be discharging with great speed, and the voltage in the network would be insufficient for the operation of all energy-intensive components and consumers.

The device of a car alternator includes the following nodes: The stator, which includes a winding, a magnet wire, winding leads, wedge grooves. The rotor, consisting of contact rings, shaft, field winding, pole.

Bearings. The alternator cover, which has holes for cooling the system. Cooling system consisting of one or two fans. Brush assembly. Rear and front cover with mounting slots. Voltage regulator. Drive unit with pulley, located on front cover side. Rectifier assembly

Once you’ve looked at all the parts of the alternator, all that’s left to do is figure out how it all works together.

When the ignition is turned on, voltage is applied to the rotor field winding from the battery through the brushes and contact rings.

The current flowing through the winding creates magnetic flux around the rotor poles. After starting the engine, when the rotor of the generator begins to rotate, the changing magnetic field crosses the coils of the stator windings, inducing an EMF in them.

An electric current appears on the stator windings.

Then through the rectifier unit, consisting of several diodes, the direct current feeds electric devices and charges the battery.

At the same time, also from the stator windings, through a separate rectifier unit, voltage is fed to the regulator, which provides a stabilized voltage by acting on the rotor field winding.

Information about generators can be read from autodoc.co.uk malfunctions will be helpful to any driver, even if it is a driving instructor.

Here is a list of malfunctions and what you should do when you find them. What could be the problem if the alternator is not delivering current or not fully charging the battery?

The cause for concern should be the fact that the headlights began to shine dimmer, or when the engine is running in the generator, you hear uncharacteristic noises.

Another obvious sign of trouble is a rapidly discharging battery.

It should be said that not all signs of failure of an alternator are so obvious.

Some of them can be determined only on the stand. That is why it is recommended for prevention to make diagnostics of the generator, after driving about 70 thousand kilometers.

Some small malfunctions of the alternator can be eliminated by yourself.

For example, if the battery is not fully charged, then first you should pay attention to the tension of the belt. If it is loose, you should retighten it.

It is recommended to use a dynamometer to check the tension.

About the use of alternators in a car from dubizzle.com also, if the alternator does not give charging current, the alternator gives charging current, but does not provide a normal charge of the battery.

Battery voltage is higher than allowed, alternator makes increased noise.

Replacement of worn parts

When replacing worn parts, you need to know a few nuances.

For example, a new alternator manifold must not only be pressed in, but also centered.

The rotor along with the manifold must be placed on a machine, where they are centered, ground and polished. If this step is skipped, the new brushes will not last long.

When restoring mechanisms, you can expect their service life to be at least as long as that of new assemblies.

The main thing is to correctly calculate the feasibility of such repairs.

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