Abstract :
The standard frequency of 25 cycles for steel mill plants was adopted many years ago, when the conditions were such that this frequency more nearly met the steel mill requirements than was possible with 60 cycles. With the coming of large central power stations, for the general supply of electric service of all kinds, the frequency of 60 cycles has come into more general use. In consequence, in considering the purchase of power from the large supply companies, the steel mills are now confronted with the problem of utilizing 60 cycles to best advantage in plants which were initially designed for 25 cycles. Various possibilities for utilization of 60 cycles in such plants are given, and the advantages and disadvantages of each are discussed briefly. The intent of the paper is to bring forward certain points for free discussion, rather than to attempt to solve the problem, it being recognized that the whole matter is too complex and contains too many varied elements to allow any entirely satisfactory general solution.