HV circuit breaker contacts

The problems presented by arcing contacts in HV switchgear are among the most difficult to solve. In service and in short circuit testing the contacts must successfully withstand the effects of arcing, must not weld and must retain a contact resistance low enough to ensure current transfer on opening the main contacts. It was to meet these conditions that the range of ELKONITE heavy duty contact material was developed. They consist of metals which are not capable of forming alloys with one another and are therefore produced by powder metallurgy. All the copper-tungsten ELKONITEs are non-ductile and are used in simple shapes. They are in general used as facings attached to copper by silver brazing