The Testing of Electrical Switchgear

Abstract

THE Department of Scientific and Industrial Research stated last year that at the request of a number of manufacturers of switchgear, it was considering the establishment of a short-circuit testing station at the National Physical Laboratory which would be capable of testing switchgear specified to be able to break a circuit having a current I flowing in it with a possible maximum voltage V across the gap of the circuit breaker, when the product of V and I is 250 million volt-amperes, certain limitations being made as to the value of V and I. The cost of such a laboratory would be very high, as it would have to be built at an appreciable distance from other laboratories and it would have to generate its own power. Only a limited number of full-scale tests could be made per annum and so it would need a large Government grant.