Applying Motor Temperature Ratings

By: Stephen Horne

Motor temperature ratings are given by the type of insulation used on the wire as well as the utilization rate. These two parameters determine the expected lifetime of the motor windings.

The vast majority of motors used today are rated for 40 °C. These motors utilize Class F insulation with a Class B temperature rise (the utilization rate). Occasionally, you will encounter a Class H motor rated for 45 °C or 50 °C. So what is the difference between these two classes and what are benefits of one over the other? And what on earth do motor temperature ratings have to do with rabbits? Continue reading “Applying Motor Temperature Ratings”