scope:

This part of IEC 60034, which is a technical specification, specifies efficiency classes for variable speed rotating electric machines not covered in IEC 60034-30-1.

The document only applies to machines that:

• have a rated power PN from 0,12 kW to 1 000 kW;

• have a rated voltage UN above 50 V up to 1 kV;

• have a rated speed nN from 600 1/min up to 6 000 1/min regardless of the number of magnetic poles;

• are designed for cooling methods IC4A1A0 (IC410), IC4A1A1 (IC411), IC4A1A6 (IC416), or IC4A1A8 (IC418) according to IEC 60034-6;

• are capable of continuous operation at their rated operating point (torque/power, speed) 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. Motors rated between S3 and S10 with a cycle time of 80 % or more may be included.

• are rated for any ambient temperature within the range of - 20 °C to + 60 °C;

NOTE 2 The rated efficiency and efficiency classes are based on 25 °C ambient temperature according to IEC 60034-2-1 and IEC TS 60034-2-3.

NOTE 3 Motors rated for temperatures outside the range - 20 °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 rated for an operating 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.

The classification only covers machines designed for operation with sinusoidal fundamental current that are not designed to be operated direct on-line (grid), for example permanent magnet synchronous machines with and without additional reluctance torque, sinusoidal reluctance synchronous machines and synchronous machines with DC field windings. This also includes induction machines that are designed exclusively for variable speed operation.

Switched reluctance synchronous machines are not covered.