The design of overhead insulated distribution lines must account for route selection, the determination of meteorological parameters, and the technical requirements for selecting overhead insulated conductors. Span lengths are limited to 40–50 meters in urban areas and 50–80 meters in rural areas. The minimum ground clearance for conductors is 6.5 meters in urban areas and 5.5 meters in rural areas.
In coastal regions, copper-core, cross-linked polyethylene (XLPE) insulated conductors should be used in conjunction with lightning arresters. In areas prone to heavy icing, medium-strength aluminum alloy core conductors should be employed, with the safety factor increased to 3.0. The standards incorporate a classification system for pollution levels and reference the technical requirements set forth by the IEC.
