Earth leakage breaker

Abstract

An earth leakage breaker includes a main body housing having, in a single structure, a casing and a case cover, and an auxiliary cover for covering the case cover. The case cover has a recess for mounting an internal accessory device. Components including a main circuit contact, a contact switching mechanism, an operation handle, an overcurrent tripping device, an earth leakage detection circuit combined with a zero-phase current transformer, and an earth leakage tripping device, are retained in the main body housing. An earth leakage operation output switch is detachably mounted in the recess formed in the case cover of the main body housing. The earth leakage operation output switch is an internal accessory device that indicates earth leakage trip operation electrically and linking mechanically with the earth leakage trip device to operate the earth leakage operation output switch in the earth leakage trip operation.