When should motor brushes be replaced?

Motor brushes are critical components in electrical motors, facilitating the transfer of electrical energy to the motor's rotor. The lifespan of motor brushes can vary, but a general guideline is that they should be replaced when they are worn to about half of their original length. This ensures that they maintain adequate contact with the commutator, which is necessary for efficient performance and to prevent problems such as increased electrical resistance.

When brushes are worn down to this level, they might still function, but their effectiveness can decrease. This can lead to sparking, reduced motor efficiency, and potential damage to both the brushes and the commutator over time. Therefore, monitoring brush wear and replacing them at the halfway point helps in maintaining the longevity of the motor and avoiding unexpected failures.

Visible damage, minor wear, or sparking can be indicators that maintenance is needed, but they do not establish the proper threshold for replacement. Monitoring wear until it reaches about half ensures that motors operate safely and efficiently.