Expected Switching Life for Safety Related Metal Clad Switchgear Applied in a Boiling Water Reactor Generating Unit

The design of the medium voltage safety related auxiliary electric system for a particular boiling water reactor (GE BWR/6) generating unit is examined and the expected number of metal-clad circuit breaker operations in each category defined in Table 6 of ANSI C37.06 is determined. The analysis of one breaker application, the diesel generator breaker, is given as an example of the methods used to determine the expected number of operations.