| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric leakage detection circuit that can prevent malfunction caused by electromagnetic wave noise.SOLUTION: A zero-phase current transformer 21 through which a main electrical path ML (main trunk lines L1D, ND, L2D) is inserted is connected to an electric leakage determination circuit 33 via signal lines 35a, 35b. The electric leakage judging circuit 33 receives a differential signal output from the zero-phase current transformer 21 via the signal lines 35a and 35b, and determines the electric leakage of the main electric path ML on the basis of the voltage difference between the differential signals. First terminals of capacitors C 11 and C 12 are connected to the signal lines 35a and 35b, and second terminals of the capacitors C11 and C12 are connected to each other by a connection line 36. An external connection terminal T1, that is, the connection line 36 is connected to the ground GND. Therefore, the second terminals of the capacitors C11 and C12 are connected to the ground GND.SELECTED DRAWING: Figure 2 |
