IEC 61467:2008 applies to insulator strings and sets comprising string insulator units of ceramic material, glass or composite material for use on a.c. overhead lines and traction lines with a nominal voltage above 1 000 V and a frequency between 15 Hz and 100 Hz. This standard also applies to insulator strings or sets of similar design used in substations. This standard establishes a standard test procedure for power arc tests on insulator sets. It also establishes a standard test procedure for power arc tests on short strings. This standard does not apply to insulator sets mounted on non-metallic poles or towers. This edition cancels and replaces IEC/TR 61467, which was published as a technical report in 1997. It constitutes a technical revision and now has the status of an International Standard.