EARTH LEAKAGE CIRCUIT BREAKER HAVING OPEN-PHASE PROTECTION FUNCTION

摘要

PROBLEM TO BE SOLVED: To provide an earth leakage circuit breaker enabling easy distinction between forced contact parting of a main contact as a result of detecting earth leakage and forced contact parting of a main contact as a result of detecting open-phase. SOLUTION: The earth leakage circuit breaker has a case 1 whose inside is partitioned with partitioning ribs 28 into three spaces consisting of two side spaces and one center space, and the main contact 26 is contained in every space. The first electromagnetic releasing device 9A and an earth leakage indicator 100 are disposed in one of two side spaces formed in the case 1, and the second electromagnetic releasing device 9B and an open-phase indicator 110 are disposed in another side space formed in the case 1. Thereby, the distinction between forced contact parting of the main contact 26 as the result of detecting earth leakage and forced contact parting of the main contact 26 as the result of detecting open-phase, becomes easy. Compact size of the earth leakage circuit breaker can be realized because an area for installing a printed board 53 becomes small by common using of power source circuit 54 for an earth leakage protection integrated circuit 50a and an open-phase protection integrated circuit 51a.