Electric motors efficiency

The new standard EN 60034-30:2009 defines the efficiency classes IE1, IE2, IE3 and IE4 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 375 kW
- 50 Hz and 60 Hz motors
- 2-, 4- and 6- pole
- operating mode S1 and S3 >79%
- designations:
- IE1 = standard efficiency
- IE2 = high efficiency
- IE3 = premium efficiency
- IE4 = Super Premium Efficiency
- New methods for determining losses and efficiency

Timetable for statutory minimum efficiency requirements:

- since June 16, 2011, motors (0.75 kW - 375 kW) must have at least efficiency IE2.
- from January 1, 2015, motors (7.5 kW - 375 kW) must have at least IE3, or be operated as IE2 with frequency converter.
- from 01.01.2017, motors (0.75 kW - 375 kW) must correspond to at least IE3, or be operated as IE2 with frequency inverter.

New regulation

There is a newer regulation on this, here is the corresponding link regarding Regulation (EU) 1781 of October 1st, 2019.

Calculate savings:

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

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