scope:

This guide applies to three-phase overhead ac transmission line (110 kV to 1000 kV) design and construction, and it can be used as reference for lower voltage levels. This guide specifies design methodologies of the overhead transmission line conductors and ground wires, insulators and fittings, insulation coordination, lightning protection and grounding, conductor arrangement, as well as tower types, loads, materials, structure, and foundations.

Purpose

This guide applies to the design of ac overhead transmission lines, and gives primary methods for electrical, structural, and foundation design. The design engineer can choose the appropriate design methods based on the location, ambient conditions, and importance of the line.