What factors can contribute to overheating in single-phase motors?

Overheating in single-phase motors can be attributed to several critical factors, with overloading, poor ventilation, and an increase in ambient temperature being some of the most significant.

Overloading occurs when the motor is required to perform tasks beyond its designed capacity, leading to an excessive demand for current, which generates additional heat. If the motor is consistently subjected to loads greater than it can handle, the heat generated will lead to insulation breakdown and eventual failure.

Poor ventilation also plays a crucial role in overheating. Motors generate heat during operation, and adequate airflow is necessary to carry that heat away. If the air circulation around the motor is insufficient, heat will accumulate, raising the temperature of the motor components.

An increase in ambient temperature further exacerbates the overheating issue. Higher surrounding temperatures limit the motor's ability to dissipate heat effectively. This scenario can be especially pronounced in poorly designed environments or when the motor operates in unconditioned spaces where the air temperature is frequently elevated.

While the other factors mentioned in the other choices can affect a motor's performance or longevity, they do not have the same direct relationship to overheating as those listed in the correct choice. For instance, using a higher voltage than rated can cause excessive current and overheating, but this specifically falls