The thermal balance of an electric motor is changed when the supply voltage varies. A voltage drop will limit the flux of the magnetic circuit, reducing the losses in the iron and the current in a vacuum. However, the motor torque must overcome the resistant torque to prevent excessive slippage.
Since the conjugate is a function of the product between the flux and the intensity of the absorbed current, if the flux falls to the current intensity increases. With the on-load current increased by the voltage drop, the motor leeson 192107.00 will heat up, increasing the losses.
An increase in the supply voltage will have more limited effects, since the no-load current rises while the on-load current decreases.
The rated power of a motor that is engraved on your nameplate represents the useful mechanical power available on the shaft, but this value is conditioned by at least two factors, such as:
(a) The temperature of the refrigerating medium must not exceed 40 °. The cooling medium is usually the ambient air. B) The altitude of the place where the engine is to operate must be at most 1000 meters.