IEC 60038 Ed. 6.2 b:2002

Applies to: a.c. transmission, distribution and utilization systems and equipment with standard frequencies 50 Hz and 60 Hz and a nominal voltage above 100 V; a.c. and d.c. traction systems; a.c. and d.c. equipment with nominal voltages below 120 V a.c. or below 750 V d.c.