What term describes the maximum torque a stepper motor can withstand without moving when the stator is energized?

• A. Holding torque
• B. Detent torque
• C. Running torque
• D. Start torque

Answer: (A)

Holding torque is the maximum torque a stepper motor can resist without moving when the windings are energized. When the stator is energized, the magnetic fields lock the rotor in position, so any load torque up to holding torque keeps the rotor stationary. This is different from detent torque, which comes from residual magnetism and mechanical fit even without energizing the coils; and from running torque, which is the torque available while the rotor is turning, and from start torque, which is the torque needed to begin movement from rest. So holding torque best fits the description.