IEC 60034-30-1 Ed. 2.0 b:2025

IEC 60034-30-1:2025 specifies efficiency classes for single-speed electric motors that are rated in accordance with IEC 60034-1 or IEC 60079-0 and are rated for operation on a sinusoidal either 50 Hz or 60 Hz, or both voltage supply.

The motors within this document:

• have a rated power PN from 0,12 kW to 1 000 kW;
• have a rated voltage UN from 50 V up to and including 1 000 V;
• have 2, 4, 6 or 8 poles;
• are capable of continuous operation at their rated power with a temperature rise within the specified insulation temperature class;

NOTE 1 Most motors covered by this document are rated for duty type S1 (continuous duty). However, some motors that are rated for other duty cycles are still capable of continuous operation at their rated power, and these motors are also covered by this document.

• are marked with any ambient temperature within the range of –30 °C to +60 °C;

NOTE 2 The rated efficiency and efficiency classes are based on 25 °C ambient temperature in accordance with IEC 60034-2-1.

NOTE 3 Motors exclusively rated for temperatures outside the range –30 °C and +60 °C are considered to be of special construction and are consequently excluded from this document.

NOTE 4 Smoke extraction motors with a temperature class of up to and including 400 °C are covered by this document.

• are marked with an altitude up to 4 000 m above sea level.

NOTE 5 The rated efficiency and efficiency class are based on a rating for altitudes up to 1 000 m above sea level.

This document establishes a set of nominal efficiency values based on supply frequency, number of poles and motor output power. No distinction is made between motor technologies, supply voltage or motors with increased insulation designed specifically for converter operation even though not all motor technologies are capable of reaching the higher efficiency classes (see Table 1). This makes different motor technologies fully comparable with respect to their energy efficiency potential.

The efficiency of power-drive systems is not covered by this document. Motor losses due to harmonic content of the supply voltage, losses in cables, filters and frequency-converters, are not covered.

Motors with flanges, feet or shafts with mechanical dimensions different from IEC 60072-1 are covered by this document.

Geared motors are covered by this document including those incorporating non-standard shafts and flanges.

This document does not apply to the following:

• Single-speed motors with 10 or more poles or multi-speed motors.
• Motors with mechanical commutators (such as DC motors).
• Motors completely integrated into a machine (for example pump, fan and compressor) that cannot be practically tested separately from the machine even with provision of a temporary end-shield and drive-end bearing. This means the motor:
  • a) shares common components (apart from connectors such as bolts) with the driven unit (for example, a shaft or housing) and
  • b) is not designed in such a way as to enable the motor to be separated from the driven unit as an entire motor that can operate independently of the driven unit. That is, for a motor to be excluded from this document, the process of separation shall render the motor inoperative.
• Totally enclosed air-over machines (TEAO, IC418), i.e. totally enclosed frame-surface cooled machines intended for exterior cooling by a ventilating means external to the machine. Efficiency testing of such motors can be performed with the fan removed and the cooling provided by an external blower with a similar airflow rate as the original fan.
• Motors with integrated frequency converters (compact drives) when the motor cannot be tested separately from the converter. Energy efficiency classification of compact drives is based on the complete product (PDS, ie. Power Drive System) and is defined in IEC 61800-9-2.

NOTE 6 A motor is not excluded when the motor and frequency-converter can be separated, and the motor can be tested independently of the converter.

• Brake motors when the brake is an integral part of the inner motor construction and can neither be removed nor supplied by a separate power source during the testing of motor efficiency.

NOTE 7 Brake motors with a brake coil that is integrated into the flange of the motor are covered as long as it is possible to test motor efficiency without the losses of the brake (for example by dismantling the brake or by energizing the brake coil from a separate power source).

When the manufacturer offers a motor of the same design with and without a brake the test of motor efficiency can be done on a motor without the brake. The determined efficiency may then be used as the rating for a motor with or without the brake.

• Submersible motors specifically designed to operate wholly immersed in a liquid.
• Smoke extraction motors with a temperature class above 400 °C.

This second edition of IEC 60034-30-1 cancels and replaces the first edition of IEC 60034-30-1 published in 2014. This edition constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous edition:

• a) Table 1 in Clause 4 revised and IE5 efficiency introduced.
• b) New efficiency tables (Table 11 and Table 12) added for IE5 nominal efficiency limits.
• c) Table 13 for interpolation coefficients revised based on IE5 limits and the coefficients limited from 0,12 kW to 0,75 kW (previously 0,12 kW to 0,55 kW). A linear interpolation shall be applied to obtain minimum efficiency between 0,55 kW and 0,75 kW.
• d) Annex A revised and added Figure A.1 showing nominal, rated, minimum efficiency and tolerance.