Motor Trending Process

Procedure for trending temperatures on Electric Motors

General Notes:

  • Pick a temperature scale at the beginning of the trending. (Either °C – Celsius or °F – Fahrenheit and always use the same scale.
    Keep the surface clean with an air hose, so dust does not build up on the inboard bearing and insulate it.
  • After blowing it off, give the bearing a few minutes to come back to steady state temperature.
  • This trending is predicated on the fact that the Delta-T (HT – AT = Delta-T) will not change if the motor stays in the same condition.
  • If the motor’s inboard bearing gets hotter over time, something is wrong. Increase frequency and check other components.
    The motor’s inboard bearing is the pivot point of all other connected components, if something goes wrong anywhere, the bearing heats.
  • Don’t worry about being off a few degrees here or there. The idea is that you will be able to see a trend. Even if some errors are introduced, so as long as you use the same repeatable method, you will see the trend.