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Electrical equipment aboard Navy ships is currently protected by current limiting fuses which provide reliable protection against hgh fault currents. Fuses, however, must be replaced after each fault event. Whle individual fuses are relatively inexpensive, the aggregate costs of replacing large numbers of them lie in the millions of dollars. Furthermore, the manpower and time required to replace blown fuses are also expensive. T h s has led us to investigate the use of modern current limiting elements to replace fuses.In the past, the excessive cost, size and weight of current limiters prohibited their widespread use. New studies show that the emerging polymer current limiter (PCL) technology will effectively limit fault currents while reducing Li fe cycle costs. T h s advantage arises because of the self-resetting capability and inexpensive procurement costs characteristic of PCLs.The protection performance and the cost advantages of polymer current h iters are described here in the context of use with distribution and load equipment. We also outline the operating mechanism of PCLs and strategies for using PCLs to improve coordination between circuit breakers. Finally, an application of PCLs as protection for solid-state devices such as Sicon Controlled Rectifiers (SCR) and MOS Controlled Thyristors (MCT) is considered.