Indoor and outdoor substations in Pennsylvania

This paper covers some points in substation design for installations for the lower voltages, including choice of location, type of building and arrangement of electrical apparatus. The subject is treated in three divisions, namely: customers' substations fed from the distribution system, customers' substations fed from the transmission system and company's substations. Attention is called to some of the advantages of both the outdoor and indoor substations for each of the different divisions. Points to be considered in the selection of locations for substations are outlined and several types of buildings, particularly the one of concrete slab construction, are described. Attention is also called to different arrangements of electrical equipments, which may be employed for installations of various sizes. Different schemes for installing high-tension switchboard apparatus are considered, attention being called to the open wire and the cell structure installations, with special reference to the concrete cell structure and the method employed in its construction.