Electric motors are mechanically simple devices with a relatively small number of moving parts. This, combined with their low vibration output, makes electric motors very reliable power supplies if used properly and within their specified ratings limits. In applications where either electric or combustion motors are viable options, the electric motor is often the more reliable solution.
Why Are Electric Motors Reliable?
When compared to a combustion engine, electric motors have very few moving parts. An average electric motor will consist of around 20 components, while the combustion engine contains upwards of 200 different moving parts.
The reduced number of moving parts means that fewer components in an electric motor experience wear over the life of the device. The reduced wear means that the motor’s individual components last longer. This leads to improved reliability and reduced maintenance, especially when compared to a combustion motor. That isn’t to say that an electric motor will last forever, just that the likelihood of a failure or repair is reduced.
Extending the Life and Reliability of an Electric Motor
The reduced number of moving parts makes it easier to pinpoint areas of potential failure within an electric motor. By paying careful attention to the condition of the motor’s wear items and replacing or reconditioning them when necessary will help to avoid a total failure.
The components of an electric motor that experience the most wear include:
- Brushes: In electric motors, brushes conduct current between stationary wires and moving parts, such as a rotating shaft. Brushes are typically constructed of one or more carbon blocks and a terminal. After extended use, brushes can wear out—in many cases, these brushes are replaceable, allowing the life of the motor itself to be extended.
- Bearings: In electric motors, bearings are used to reduce the friction between components, and to keep the shaft or rotor in proper position. Bearings come in many types and shapes. The most common types of bearings used in electric motors include simple sleeve, ball, roller and sealed. As bearings lose lubrication, they begin to fail, and must be serviced or replaced.
Each of these components is relatively inexpensive and easy to replace or repair upon failure. This ease of maintenance and low-cost repair are also key factors in the reliability of an electric motor.