Class codes IE1, IE2, IE3 and IE4 have been introduced. This system is similar to the IP, IM and IC codes uses for many years in the electrical machinery industry. IE stands for ‚International Energy Efficiency Class‘ and is expected to be widely accepted.
Comparison of efficiency classes
In a direct comparison with the same motor, it can be assumed that the efficiency determined with the new measuring method for IE motors will be lower.
For example, a 4 pole 15 kW EFF1 motor with an efficiency of 91.8% is physically identical to a 4 pole IE2 motor with an efficiency of 90.6%.
The main difference between the EFF and IE classes is in the method used to determine the efficiency.