Capacitor-start, capacitor-run motors provide

• A. Medium (or high) running and high starting torque
• B. Low torque and low running torque
• C. Only starting torque
• D. Low running torque but high current draw

Answer: (A)

Capacitor-start, capacitor-run motors are designed to create a strong rotating field by using a capacitor in the auxiliary winding. The starting capacitor delivers a large phase shift between the main and auxiliary currents, producing high starting torque to get the motor up to speed. Once running, the run capacitor stays in the circuit to improve torque during operation, efficiency, and power factor, so the motor maintains solid running torque as it reaches speed. This combination results in both high starting torque and medium to high running torque, rather than weak torque or torque limited only to starting.