| 摘要 |
PURPOSE:To enable a phase discrimination only base on the information at one terminal for phase discrimination leaving the destribution line in live state by detecting a measuring signal on the receiving side with the overlapping thereof over a specific phase on the receiving side between destribution line sections. CONSTITUTION:An output (a) of a voltage transformer 1 on the transmission side is outputted synchronizing a specific phase through a waveform shaping circuit 2, a measuring signal generator 3 and a synchronization circuit 4. The output (d) of the synchronization circuit 4 overlaps a black phase voltage, for instance. On the receiving side for phase discrimination, a voltage transfer 6 for drawing phase voltages U1, V1 and W1 are provided to a phase discrimination circuit 9 via a signal voltage separation circuit and a waveform shaping circuit 8 and the circuit 9 transmits an output signal from a U phase AND circuit. This makes it clear that the U phase corresponds to the black phase on the transmission side. Thus, a phase discrimination can be performed only based on information line at one terminal for phase discrimination leaving the destribution line in live state. |
