Failure rates of air blast breakers

Summary form only given. This panel presentation discusses the results of an extensive study launched by Hydro One aimed to determine air blast circuit breaker reliability measures through statistical analysis of outage data. The study concentrated on how the failure rate of breakers depends on such factors as equipment age, voltage level, manufacturer, and number of operating interventions. Planned outage rates due to equipment maintenance were also investigated. Results presented in this presentation are based on outage records covering the period of 12 years with 318 breakers.