A New Design 34.5 to 69 Kv Intermediate Capacity SF6 Circuit Breaker

A new line of SF6 breakers has been developed to cover the range of 34.5 to 69 kv and 500 to 2,500 mva (megavolt-amperes). A new puffer-type interrupter is used to operate in sealed and grounded metal tanks at 60 psig (pounds per square inch gage) gas pressure. Interrupting tests and impulse voltage withstand tests have been made according to proposed new ASA (American Standards Association) standards. Capacitor switching tests have been made which show these breakers to be well suited for switching large single or multiple banks.