The Fault Ground Bus Its Use and Design in Brunot Island Switch House of Duquesne Light Company

This paper describes the ground protection in the Brunot Island switch house of the Duquesne Light Company at Pittsburgh, Pa. This switch house constructed on the vertical isolated-phase plan, is divided structurally into several completely insulated sections. The well known fault ground bus system of protection is applied and made effective by the special features of construction not heretofore used. Details of building construction and of fault ground bus application are given. Arrangements for heating, ventilating, and lighting the buildings are such as not to interfere with phase isolation and insulation. Oil circuit breaker mechanisms are insulated where necessary to maintain the building subdivision into insulated sections. The fault ground bus location, connections, and special details of construction are outlined. Preliminary tests, relay settings, and operating results are given.