CIGRÉ Technical Brochure No. 510: Final Report of the 2004 – 2007 International Enquiry on Reliability of High Voltage Equipment, Part 2 - Reliability of High Voltage SF6 Circuit Breakers

In the past, two circuit breaker reliability surveys have been carried out. The first was performed in 1974 - 77 and concerned nearly 79 000 circuit breaker years of service. In the second surveydata was collected in the period 1988 - 91 and almost the same number of circuit breaker years were covered, but the survey was limited to single pressure SF6 technology. This report gives the results of the third international enquiry (called “present survey” in this report). The scope of this survey is mainly based on the structure and questions contained in the second survey (called “previous survey” in this report) ; therefore, in many instances trends and comparisons can be made. Again, the present survey concentrates on live tank, dead tank and GIS high voltage circuit breakers based on single pressure SF6 technology.