Design Implications of Prow Formation During Electrical Contact Closure

The contact resistance behavior of electrical contacts which were closed on oxide and sulfide contaminants is reported. The minimum wipe which is required to break through contaminants and to produce ´a minimum contact resistance is approximately equivalent to the diameter of the load-bearing area. The tendency of contaminant accumulations, which are formed at the front surface of the moving contact, to break away and pass between the contacts is correlated with the extent of wipe. Some implications of these results in the design of electrical contacts to function in contaminating environments are discussed.