A 69-kv compressed-air circuit breaker

A 5,000,000-KVA COMPRESSED-AIR circuit breaker that is rated at 69,000 volts with 2,000-ampere continuous current-carrying capacity has been developed and tested. The breaker is completely metal enclosed. Six condenser bushings extend through the roof for mounting of current transformers, potential devices, and for connection to the customer's bus structure (Fig. 1). Verification tests included interrupting demonstrations at 66, 44, and 22 kv. Tests with varying rates of rise of the transient recovery voltage were also included in the testing program.