Circuit Breaker Standards and the Statistical Approach

The increasing dependency of power circuit breaker insulation standards (i.e., switching and lightning surge ratings) on a statistical approach is discussed with particular emphasis on design considerations and testing. The mathematical meaning and significance of such aspects of Statistics as Reliability, Probability, and Confidence and their relationship to circuit breaker development are presented in basic terms. The various statistical techniques are illustrated by a number of practical examples which can be readily applied elsewhere by power engineers who have minimal experience in the use of statistics.