Generators vs. Electric Motors: What’s the Difference?

Many people use the words “motor” and “generator” synonymously. This mistake is a common occurrence since people associate both machines with electricity. While they do share some similarities, they function in fundamentally different ways.

Understanding the differences between generators and electric motors is crucial—you don’t want to end up with a piece of equipment that doesn’t work for you. Discover the variations to ensure you have the best machinery for your operations.

Differences in Definition

Generators use mechanical force to create electricity. They work based on electromagnetic induction. Magnetism and electricity have a strong relationship; through various power sources, generators produce electromotive forces with the help of conductors and magnetic fields.

Electric motors have the opposite definition—they use electricity to generate mechanical force. People who use “motor” and “generator” interchangeably are making a critical error since they are actually antonyms. Instead of using magnetic fields to produce a force, conductors experience force in the field.

Differences in Power Source

Another key difference between generators and electric motors is their power source. Electric motors receive energy from direct current (DC) sources like batteries. They may also use a generator to obtain energy through alternating currents (ACs).

Motors can use generators to generate power; however, generators need their own source of energy. They need a mechanical force to turn blades that create electricity. Common power sources for generators include combustion energy, wind and steam turbines, and hydraulic machines.

Differences in Fleming’s Rule

In the 19th century, physicist John Ambrose Fleming established a system for directions of motion and current flow. He developed two guidelines governing electric motors and generators: the left-hand and right-hand rules.

Fleming’s left-hand rule shows how a current flows through a conductor in a magnetic field. Conversely, Fleming’s right-hand rule demonstrates how conductors induce currents in a magnetic field.

The left-hand rule applies to electric motors, while the right-hand rule explains generators. You can create a visual representation of these laws by holding up your thumb perpendicular to your pointer and middle fingers on the appropriate hand. Each finger points toward the direction of magnetic force, magnetic field, and current, respectively.

Hire Illinois Electric Works for Your Motor and Generator Needs

If this industry jargon sounds confusing, don’t worry—Illinois Electric Works knows which machine your facility needs. Our Midwestern crane and hoist repair services can fix your electric motors and generators with little downtime. Schedule a consultation by contacting us today!