Abstract :
With the increased capacity of individual units of alternating-current generators it is natural that the potential for which these generators are wound should be continually increased. It commends itself to limit the current capacity of generators, as the distribution and conduction of large currents from the generators to the switchboards is cumbersome and expensive. Historically, the increase in voltage with the increased capacity of individual units and of power plants may be briefly summarized. The Niagara generators of approximately 3500 kw. capacity, put into operation about ten years ago, were designed for 2200 volts. The 3500 kw. generators of the Metropolitan Street Railway Company, of New York, were designed for 6600 volts. The 5000-kw. generators installed in the stations of the Interborough Rapid Transit Company, in New York, were designed for 11,000 volts. The large generators for the Brooklyn Rapid Transit Company, of 7500 kw., were designed for 11,000 volts also.
