Overcurrent protection in large-capacity shipboard electric systems

IN all power systems the continuity of power service is dependent upon the characteristics of the devices that are employed in the distribution systems and the proper co-ordination of these devices. It is desirable to have these devices so arranged as to isolate any fault with a minimum disruption of power in the remainder of the power systems. The methods of accomplishing this on navy ships and the limitations of available protective devices were discussed in a previous paper.1 Shipboard power plants have continued to become larger, thus resulting in higher available fault currents. This paper describes these larger systems and discusses the shipboard protective systems and devices employed.