CIRCUIT BREAKER HAVING SEPARATE RESTRAINED AND UNRESTRAINED ZONE SELECTIVE INTERLOCK SETTING CAPABILITY

摘要

A circuit breaker system and method having zone selective interlock featureswith separate restrained and unrestrained setting capability is provided. Thesystemand method include the transmission of a selective interlock signal from adownstream circuit breaker to an upstream circuit breaker in the event of afaultcondition. The upstream circuit breaker upon receipt of this signal changesthetripping response of the second circuit breaker to a restrained mode. Thecircuitbreakers include features enabling the user to modify and adjust both therestrainedand unrestrained trip curves associated with both the restrained andunrestrainedmodes of operation.