New testing method for the classification of contact materials for vacuum circuit breakers

Abstract

A new testing method to classify contact materials for high-current interruption with vacuum circuit breakers (VCB) is described. The testing effort is reduced by diminishing the contact gap and the contact area as well as by an adequate testing circuit. Consequently, the number of experiments can be increased for the benefit of a high statistical certainty in the classification of contact materials. The test results are in good agreement with the results of full-size short-circuit current interruption tests carried out in a high-power testing laboratory with VCB equipped with contact materials classified in the new testing circuit.