Short Circuit Testing Methods for Generator Circuit Breakers with a Parallel Resistor

ANSI-Standard C37.09-1979 describes design and testing of AC high voltage circuit-breakers under fault conditions. For synthetic test methods application guide ANSI/IEEE C37.081-1981 is added. Presently, generator circuit-breakers of the airblast type are built with a low ohmic parallel damping resistor. At this time there are no standards establishing test circuits or test procedures for this type of circuit-breaker. This article outlines the problems involved in testing generator circuit-breakers equipped with parallel resistors and gives a qualitative analysis of several test circuits.