Which motor type generally has lower maintenance due to no brushes?

Which motor type generally has lower maintenance due to no brushes?

• A. DC Motors
• B. Synchronous Motors
• C. AC Motors
• D. Induction Motors

Answer: (C)

Brush wear drives a lot of motor maintenance. DC motors use carbon brushes and a commutator to switch current as the rotor turns, which causes wear, sparking, and periodic replacement. AC motors, especially induction motors, operate without any contacting brushes—the stator’s rotating magnetic field induces currents in the rotor, so there are no brush wear issues to manage. That absence of brushes means fewer parts to wear and less routine maintenance. Some synchronous motor designs can use brushes for rotor excitation or have slip rings, so maintenance needs can vary, but in general AC motors—without brushes—provide the lower-maintenance option.

Brush wear drives a lot of motor maintenance. DC motors use carbon brushes and a commutator to switch current as the rotor turns, which causes wear, sparking, and periodic replacement. AC motors, especially induction motors, operate without any contacting brushes—the stator’s rotating magnetic field induces currents in the rotor, so there are no brush wear issues to manage. That absence of brushes means fewer parts to wear and less routine maintenance. Some synchronous motor designs can use brushes for rotor excitation or have slip rings, so maintenance needs can vary, but in general AC motors—without brushes—provide the lower-maintenance option.