This part of IEC 60034 specifies efficiency classes for single-speed, three-phase, 50 Hz and 60 Hz, cage-induction motors that:
• have a rated voltage UN up to 1 000 V;
NOTE The standard also applies to motors rated for two or more voltages and/or frequencies.
• have a rated output PN between 0,75 kW and 375 kW;
• have either 2, 4 or 6 poles;
• are rated on the basis of either duty type S1 (continuous duty) or S3 (intermittent periodic
duty) with a rated cyclic duration factor of 80 % or higher;
• are capable of operating direct on-line;
• are rated for operating conditions in accordance with IEC 60034-1, Clause 6.
Motors with flanges, feet and/or shafts with mechanical dimensions different from IEC 60072-1 are covered by this standard.
Geared motors and brake motors are covered by this standard although special shafts and flanges may be used in such motors.