To prevent costly motor problems and unnecessary downtime, don’t overlook the commutators and brushes when performing motor maintenance. Use the following tips to help ensure the longevity of these essential parts.
- Observe commutators and brushes as the motor runs: When the pressure on a commutator is correct, the brushes will not spark or make a lot of noise.
- Brush observations: When the motor is stopped, the brushes should have similar tension and move freely in their holder. A brush that’s seated well will appear to have a polished surface.
- Brush replacement: If there is doubt about a brush working well until the next inspection, replace it.
- Commutator observations: A commutator that’s in good shape is smooth, clean and has a burnished appearance.
- Commutator and brush cleaning: Clean grit, dirt, oil and other debris that you find in the bush holders, posts and commutator bars. When applicable, trim frayed or unevenly worn brushes so they’re square.
- Lubrication: Use mineral oil on commutators.
- Prevent short circuits: Inspect the insulation between a commutator’s segments and remove burrs, filings and metallic dust. If the insulation has too much oil in it, you may need to replace the insulation.
- Red flags: Indications of a potentially serious problem with a DC motor include:
- Grooves around the commutator’s circumference.
- Brushes that spark, chatter, leave imprints, show signs of arcing, or have excessive or uneven wear.
- Worn or dirty commutators.
When maintaining your motor or building a new one, keep in mind that Sinotech offers a wide range of commutator styles and a full line of brushes ground to your exact specifications. Call Sinotech to learn about its competitive pricing and manufacturing services.