| 摘要 |
PURPOSE:To facilitate searching of fault points in low resistance ground faults by providing a check pulse generating circuit within a pulse receiver, and if necessary, generating check pulses thereby permitting the operation checking of the receiver. CONSTITUTION:In the case of searching the fault point in a high voltage distribution line, an antenna 5 is put on the line, and the current flowing in the line is inductively detected. In case a fault point is a low resistance ground fault, virtually no current flows in the line past the fault point, and the detected current is equal to zero, and therefore is cannot be discriminated from the fault of a detector. Thereupon, in such a case, the antenna 5 is spaced from the distribution line, and a signal changeover circuit 12 is changed over to selectively connect a receiving gate circuit 15 and a check pulse generating circuit 13. Check pulses are generated by operating a switch 14 for checking and whether the indication of a detecting meter 17 is a predetermined value or not is checked. |
