IEC Standards for electric motors
In 1999, the European Commission established different efficiency classes for electric motors to reduce energy consumption and to create awareness among various industries to the importance of a more sustainable environment. These efficiency classes were called the EFF standards. However, in 2008 these EFF standards changed to the current IEC standards for electric motors to overcome the international inconsistencies in regulations between electric motor standards and efficiency classes. For example, the US established the NEMA standards for electric motors, which differed a lot from the EU standards. These standards were set by a new commission called the International Electrotechnical Commission (IEC).
IE4 motors by Magnetic Innovations
The following IEC standards were established in 2008:
Since 2014 the power range was extended for electric motors and was set between 0,12 kW and 1000kW. Furthermore, since the 1st of January 2017 electric motors with a rated output of 0,75-375 kW must meet either IE3 efficiency or IE2 if fitted with VSD’s.
International electric motor efficiency standards
The following table shows a comparison between the in 2008 established IEC standards (IEC/EN 60034-20-01) and other international norms:
Electric motors included by the IEC standards
- Single speed electric motors (single and three phase), 50 and 60 Hz
- Line-start permanent magnet motors
- 2, 4, 6 or 8 poles – Rated output PN from 0.12 kW to 1000 kW
- Rated voltage UN above 50 V up to 1 kV
- Motors, capable of continuous operation at their rated power with a temperature rise within the specified insulation temperature class
Electric motors excluded by the IEC standards
- Motors designed to operate wholly immersed in a liquid
- Brake motors, when the brake cannot be dismantled or separately fed.
- Single-speed motors with 10 or more poles or multi-speed motors
- Motors completely integrated into a machine (for example, pump, fan or compressor) that cannot be tested separately from the machine.
- Motors specifically designed to operate:
- At altitudes exceeding 4000 meters
- Where ambient air temperatures exceed 60°C
- In maximum operating temperatures above 400°C.
- Where ambient air temperatures are less than –30°C (any motor) or less than 0°C (water-cooled motors)
- Where the water coolant temperature at the inlet to a product is less than 0°C or exceeds 32°C
- In potentially explosive atmospheres as defined in Directive 94/9/EC