Which type of motor is generally less expensive and requires less maintenance?

• A. AC
• B. DC
• C. Servo
• D. Stepper

Answer: (A)

AC motors, especially induction types, are generally the least expensive to buy and require the least maintenance. They have a very simple, rugged design with a rotor that doesn’t use brushes or a commutator, so there are far fewer wear parts. That means less regular maintenance and fewer part replacements over time. They’re also produced in enormous quantities for a wide range of applications, which drives down unit cost. By contrast, DC motors rely on brushes and a commutator that wear and need periodic replacement; servo systems add high-cost feedback and dedicated drives; and stepper motors need drivers, sometimes additional cooling, and can be less forgiving under load. All of this makes AC motors the more economical and maintenance-friendly choice overall.