Dynamic ARC Analysis of Short-Line Fault Tests for Accurate Circuit Breaker Performance Specification

The continuing program of analysis of circuit breaker short-line fault test data has culminated in a practicable method for getting complete performance and circuit information quickly from presently available test data and a simple, time-sharing computer program. A dynamic model of the circuit breaker arc near current zero using both the Cassie and the Mayr differential equations, has been solved by computer including interaction with resistance and capacitance shunts. By expressing the critical cases which just interrupt in terms of voltage and current slope coefficients, the model is fitted to key measurements from the test oscillograms. More precise specification of performance and its dependence on electrical parameters results.