What is a common maintenance requirement for motors?

Lubrication of bearings is a vital maintenance requirement for motors because it directly impacts the smooth operation and longevity of the motor. Bearings allow for smooth rotation of the motor's rotor, and without proper lubrication, they can experience increased friction and wear. This can lead to overheating, excessive noise, and potentially catastrophic failure of the motor.

Regular lubrication reduces friction between moving parts and helps dissipate heat generated during operation. It also helps protect bearings from wear caused by contaminants and rust. Different types of motors may require specific lubricants and maintenance intervals, so it’s important to refer to the manufacturer's guidelines to ensure optimal performance.

In contrast, replacing the circuit board is not a routine maintenance task. It's typically necessary only when there is an electrical failure. Adjusting voltage levels could be part of setup or troubleshooting rather than regular maintenance. While cleaning the exterior of the motor can maintain appearance and prevent dust buildup that could affect airflow, it does not have the same critical impact on operational functionality as lubrication does.