| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a zero-phase current transformer having improved productivity and high earth leakage detection sensitivity. <P>SOLUTION: The zero-phase current transformer comprises a core 12, and primary side coils 13a, 13b and a secondary side coil 14 in which the number of turns of the coil is two times or larger. For wiring from a power supply 15 to equipment 16, the primary side coils 13a, 13b of the zero-phase current transformer 11 are used as a wiring path. Earth leakage is generated in the equipment 16, unbalance is generated in current flowing through the primary side coils 13a, 13b of the zero-phase current transformer 11, and an output voltage Vg corresponding to a current difference by the earth leakage is obtained in the secondary side coil 14 according to a current difference by the unbalance. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
