Hydro-Quebec's concerns related to performances of SF/sub 6/ circuit-breakers

Hydro-Quebec's concerns regarding circuit breaker reliability are presented. Emphasis is placed on two aspects crucial in determining line charging current breaking capacity, i.e., the arc duration and the test circuit configuration. The importance of manufacturing quality for the arcing contacts, nozzles and gasket is discussed. Test criteria at 20 degrees C for simulating breaking tests at -50 degrees C are given. Hydro-Quebec's requirements for testing the tightness of SF/sub 6/ breakers are presented together with a reliable leakage-measuring method.<
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