This part of IEC 60034 defines criteria for assessing the insulation system of stator/rotor windings which are subjected to voltage-source pulse-width-modulation (PWM) drives. It applies to stator/rotor windings of single or polyphase AC machines with insulation systems for converter operation. It describes qualification tests and quality control (type and routine) tests on representative samples or on completed machines which verify fitness for operation with voltage source converters. This standard does not apply to: – rotating machines which are only started by converters; – rotating electrical machines with rated voltage ≤ 300 V r.m.s.; – rotor windings of rotating electrical machines operating at ≤ 200 V (peak).