To specify the block frequency property of a filter to the output frequency property of a modulation frequency output circuit, by integrating an inverter including a modulation frequency output circuit, and an earth leakage breaker including a filter and a leakage detecting circuit.
In an earth leakage breaker for an inverter, the frequency converting circuit 11 converts the frequency of an AC current path 1, and a modulation frequency output circuit 12 supplies a frequency converting circuit with modulation frequency. Furthermore, this earth leakage breaker is constituted by integrating a breaking device for a contact, a break detecting circuit 8 to operate the breaking device, and a filter 13. Hereby, it becomes possible to specify the block frequency of the filter 13, limiting it to the output frequency of the modulation frequency output circuit 12, and this can completely check the components of high frequency of modulation frequency flowing in through a zero-phase current transformer 7 from an AC current path 1, and can surely check the occurrence of malfunction.
HATAKEYAMA YOSHIHIRO
KANEO SHIGERU
YAGISAWA MAMORU
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