| 摘要 |
Electrical power failure or an unnecessary alarm, which is caused by an unexpected motion caused due to an unexpected current caused due to grounding on the power source side, occurs as a production problem. Provided is an electrical leakage detection apparatus which prevents an unexpected motion without inhibiting an electrical leakage detection operation in a highly sensitive operation area. An output control circuit which monitors an electrical circuit-to-ground voltage which may cause an unexpected motion and which occurs between a B-type transformer grounding phase of an electrical circuit to be monitored and D-type or C-type grounding electrode, or a grounding structure of electrical equipment connected thereto, said output control circuit determining the phase of leakage current detected by a residual current transformer on the basis of the voltage, said output control circuit stopping the output operation of the electrical leakage detection apparatus when the leakage current is an unexpected current passing from the load side (L) to the power source side (K), i.e., the transformer side of the residual current transformer, and the electrical circuit-to-ground voltage exceeds a operation sensitive voltage stabilization value which has been appropriately stabilized, is added to the electrical leakage detection apparatus. Thus, an unexpected motion caused due to an unexpected current is prevented without inhibiting the highly sensitive operation area of the electrical leakage detection apparatus. |
