IEC 60034-30-1:2014 specifies efficiency classes for single-speed electric motors that are rated according to IEC 60034-1 or IEC 60079-0, for operation on a sinusoidal voltage supply. This standard establishes a set of limit efficiency values based on frequency, number of poles and motor power. No distinction is made between motor technologies, supply voltage or motors with increased insulation designed specifically for converter operation even though these motor technologies may not all be capable of reaching the higher efficiency classes. This makes different motor technologies fully comparable with respect to their energy efficiency potential.