Why do the carbon brushes of DC motors wear out quickly?

What causes the carbon brushes of DC brushed motors to wear out so quickly? This is a very common problem, the following is to give you an analysis of the specific reasons.

1. Poor commutator condition

Rough, out-of-round or poor contact surfaces can lead to accelerated brush wear, and poor commutator condition can lead to electrical and mechanical wear of the carbon brushes. To ensure that the commutator can make contact with carbon brushes, the industry recommends that the commutator surface should be round with a roundness of 0.002mm or less. In addition, a poorly contoured commutator will cause the spring to bend more frequently, reducing spring life and increasing the chance of insufficient spring pressure.

2. Low spring pressure

Insufficient spring pressure will accelerate brush wear. Insufficient spring length tends to lose the spring force that drives the carbon brushes as they wear, and the spring fatigues over time, which reduces the effectiveness of the brush surface and accelerates the rate of brush wear.

3. Incorrect installation or uneven brush holder spacing

Incorrectly mounted brush holders can cause a variety of problems. Incorrectly mounted brush holders have the potential to increase brush wear and damage contact surfaces.

These are the three causes of brush motors leading to rapid wear of carbon brushes, I hope you have a reference, for more information about this, please feel free to consult us