Final Report of the 2004 - 2007 International Enquiry on Reliability of High Voltage Equipment - Part 5 - Gas Insulated Switchgear

Results from a world wide utility survey of failures and service experience with gas insulated switchgears (GIS) are presented. The surveyed service experience comprises 88 971 GIS three phase circuit breaker bay years. Statistical information about 358 major and 1 505 minor failures - such as origin, cause and failed subcomponent - are provided. In addition, failure frequencies as a function of voltage level, application, technology, age, design and maintenance strategy are presented.