Abstract :
The southern portion of the Pacific Coast is comparatively free from lightning disturbances and the number of such disturbances, as compared with the number of lightning storms in other sections of the United States, is quite small. However, the expansion of the high voltage transmission network with the installation of many additional substations and further expansion of distribution systems has made necessary the use of some form of protection against transient high voltages throughout the system of the Southern California Edison Company.
