Specifies procedures for electrical and mechanical tests on insulators of ceramic material or glass for use on a.c. overhead power and traction lines with a nominal voltage greater than 1000 V and a frequency not greater than 100 Hz. This Standard applies to string insulator units, pin insulators, line post insulators, shackle insulators and insulator units for overhead traction lines. This Standard is based on but not equivalent to, and has been reproduced from, IEC 60383-1:1993.