What occurs when a three-phase motor is subjected to an unbalanced load?

When a three-phase motor is subjected to an unbalanced load, it undergoes a condition known as single phasing. This situation arises when one or more phases of the motor's supply voltage are lost or have significantly different current levels due to the unequal load. As a result of this imbalance, the motor experiences increased currents in the remaining phases, which can cause excessive heat generation and ultimately lead to overheating.

Overheating harms the motor's insulation and other components, which can reduce the motor's lifespan and increase the risk of mechanical failure. This is why understanding load balance is critical in the operation of three-phase motors, as maintaining balanced loads helps ensure efficient operation and longevity of the equipment.