Do motors have classes of ratings?
There are four typical insulation classes for motors and associated maximum operating temperatures.
Insulation classes for motors define the acceptable maximum ambient operating temperatures for different motors. There are four typical insulation classes for motors and associated maximum operating temperatures. Class A (105 degrees C), Class B (130 degrees C), Class F (155 degrees C), and Class H (180 degrees C). The motors used in Air Vent powered attic ventilator products have an insulation Class B rating.