Capacitor-start, capacitor-run motors provide what torque characteristics?

• A. Low running torque and no starting torque
• B. Medium (or high) running and high starting torque
• C. High running torque and low starting torque
• D. Low running torque but high current draw

Answer: (B)

Capacitor-start, capacitor-run motors get a strong push at startup because the start capacitor injects a large, phase-shifted current into the auxiliary winding, creating a powerful rotating magnetic field that produces high starting torque. Once running, the run capacitor keeps the auxiliary winding energized with the proper phase, improving torque during operation compared with a motor without a run capacitor. So you get high starting torque along with medium to high running torque, depending on the design.