What does "stalling" indicate in electric motors?

Stalling in electric motors refers specifically to the condition when the motor is energized but not rotating. This condition can occur when the load on the motor exceeds its capacity to overcome it, causing the motor to draw excessive current while its rotor remains stationary. During a stall, the rotor fails to turn, resulting in a significant increase in current draw, which is a crucial indicator of an overloaded condition.

This phenomenon is vital to understand because it can lead to overheating of the motor, potential damage to the windings, and tripping of overload protection devices. Recognizing that a motor in a stall condition is drawing a high current is critical for diagnosing motor issues and ensuring the motor's longevity.

When considering other options, maximum speed refers to the motor running efficiently, without any blockage or excessive load. A current limitation implies that the motor is not consuming more than its rated current, which is not synonymous with stalling. Running under heavy load could still allow the motor to operate, just at a reduced speed, instead of stalling entirely. Therefore, the definition of stalling is specific and aligns directly with the state of the motor being energized without rotation.