| 摘要 |
PROBLEM TO BE SOLVED: To provide a leakage detecting device capable of improving the linearity of pulse signals in accordance with the wave height of leakage input waveforms and improving detecting accuracy while restraining current consumption without increasing charge and discharge currents for an improvement of the linearity. SOLUTION: In the leakage detecting device, integrating circuits 13, 14 alternately charge outputs of a zero-phase-sequence current transformer 4 and discharge during the period of not charging, a VF conversion circuit 15 resets the integrating circuits 13, 14 when the size of waveforms of output signals of the integrating circuits reaches a given level and at the same time changes over a switch 12 through a switching circuit 16 to output pulse signals of frequencies in accordance with signal waveforms inputted from a zero-phase-sequence current transformer 4, and an arithmetic circuit 17 carries out an interruption operation from both judgment results of a leakage input waveform width from the transformer 4 and an integrated value of the pulse signals outputted from the VF conversion circuit 15. COPYRIGHT: (C)2004,JPO&NCIPI
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