How Alternators Work

How Alternators Work

Alternators are one of the most critical components to your heavy machinery electrical systems. They are responsible for keeping your battery fully charged as well as powering several electronic components on their own, including lighting, control, and management systems. Without it, most electrical systems on your heavy-duty equipment would not function. But how does an alternator actually work?

This article will give you an overview of how alternators work to support your heavy-duty machinery.


How Heavy-Duty Alternators Work

The alternator creates electrical energy from mechanical energy. When your engine is running, it will turn a pulley that is attached to the alternator. This rotates the rotor shaft, a magnetic core within a stator lined with copper winding. The rotor will begin rotating extremely fast, creating a magnetic field that generates alternating current (AC) around the coil.

This is what produces the power to keep your battery charged and provides the electrical energy needed for other systems on your heavy-duty vehicle to function.

As your battery drains, the power generated by the alternator is sent to the battery through a voltage regulator. This is to prevent overload which could cause electrical failure and damage the battery. This process repeats as long as your battery needs power and your engine is running.


How to Identify Alternator Issues

Operators are quick to guess any electrical faults are the cause of a damaged battery, however it is also important to check your alternator is working as intended. Any number of electrical faults such as headlight issues, unusual sounds and smells, and difficulty starting your machinery could be the result of a damaged alternator.

When you notice problems with your heavy-duty electrical systems, make sure to check your alternator when diagnosing the issue rather than assuming it is the battery. Even if it is the battery, still make sure to assess the quality of your alternator as a damaged battery can cause damage to the alternator.

Check your machine monitoring system for error and warning codes.


How to Keep Your Alternator Working

The risk of your alternator getting damaged is exacerbated on construction sites due to the stressful conditions that heavy machinery undergoes every day. Some of the most common causes include overheating and water damage, but loose or corroded battery terminals as well as incorrect jump-starting of your heavy machinery puts unwarranted stress on the alternator.

Always make sure your alternator and surrounding parts are kept dry clear of dust and dirt and well-maintained. If you notice any damaged parts, always make sure to replace them as soon as possible to avoid further damage that could result in costly downtime of equipment is left unchecked.

If you need a replacement alternator for your heavy-duty equipment, we are here to help. At Jaytrac, we stock and supply replacement parts of heavy machinery including electrical components for Caterpillar, Komatsu, Volvo and Cummins machinery. If you need a replacement alternator, please contact us via telephone at 01604 491 133 or email us at