What happen when inlet airflow of an AC vacuum motor is blocked

[Qwe]

What happen when inlet airflow of an AC vacuum motor is blocked? Based on quick test, fan case motor gets very hot, but why not motor winding? Hope to get some help here..

[om_tech_support_AC]

Hi Qwe,

What is the part number of the motor you are using? How are you measuring the temperature of the windings?

[Qwe]

I test it using normal universal motor at 230vac. Thermocouples are used but only managed to place closed to the winding rotor. I found the fan case temperature shot up very fast and even higher than copper winding! Will this due to thermal radiation?

[om_tech_support_AC]

Since it is not an Oriental Motor product I cannot determine what factors are causing the fan to heat up faster then the winding. Also even if it was our product the AC induction motors we offer are not vacuum rated.