Electric motors efficiency

The new standard EN 60034-30:2009 defines the efficiency classes IE1, IE2, IE3, IE4 and IE5 for low-voltage three-phase motors. The IEC 60034-2-1:2007 standard also introduced new methods for measuring the efficiency of low-voltage three-phase motors. This leads to a more accurate determination of the additional losses. The better the efficiency class, the more complex it is to produce the motors. In relation to the service life of the motor, however, the acquisition costs are only a few percentage points and are amortized in a short time through the energy costs saved.

The most important key points at a glance:

- EU-wide uniform efficiency classes
- Scope for low-voltage three-phase motors from 0.75 to 1000 kW
- 50 Hz and 60 Hz motors
- 2-, 4- 6 and 8- pole
- Operating mode S1 and S3 >79%
- Designations:
   IE1 = Standard Efficiency
   IE2 = High Efficiency
   IE3 = Premium Efficiency
   IE4 = Super Premium Efficiency
   IE5 = Ultra Premium Efficiency

Here is an excerpt of the legal minimum efficiency levels:

- From June 1, 2021, three-phase motors from 0.75 kW to 1000 kW must meet at least IE3 efficiency. Likewise, electric motors from 0.12 kW to 0.55 kW must be manufactured at least in accordance with efficiency class IE2.

- From July 1, 2023, at least efficiency class IE4 will be required for electric motors in 2/4/6-pole versions from 75 kW to 200 kW. Likewise, from this period, at least IE2 efficiency will be required for single-phase motors from 0.12 kW.

New regulation

Here is the corresponding link to Regulation (EU) 1781 of October 1st, 2019.

Calculate savings:

You can determine the savings potential of the new motors using our energy saving calculator.

SEO= Electric motors efficiency E1, IE2, IE3, IE4, IE5