1926 Lightning Experience on 132-Kv. Transmission Lines

This paper deals with the interruptions due to lightning on an extensive interconnected 132-kv. system during the year 1926, a similar record covering part of the system having been reported previously.² A layout of the system is shown and details of the type of line and tower construction are given in considerable detail. The lightning performance of different sections of the line have been reduced to a common basis and discussed from the point of view material of line structure, height of line, ground wire, and line protective equipment. Changes in tower design are discussed in the light of experience gained in the past. The work done the past year to reduce the lightning troubles at the stations is described. The efficacy of the ground wire seems very definitely shown but it is believed further study and attention should be given this matter as a means of reducing the lightning voltage on transmission lines, particularly to reducing the lightning voltage at and near a switching station. The problem of determining the damage to linie conductors, etc., is an important one. Data on this are at present incomplete, but it is planned to obtain a systematic record in the future which will, it is believed, supply valuable design information.