| 摘要 |
In a circuit arrangement for initiating a switching or indicating process, which consists of two physically separate points, preferably circuit parts which are allocated to the section ends of a high-voltage line, square-wave pulses which have a fixed phase relationship to the line current of the first point and needle-shaped sampling pulses, which have a fixed phase relationship to the line current of the second point, are formed and compared with one another. The adjustable edge separation of the individual square-wave pulse from the central position of the associated sampling pulse is used as a measure for the reliably judged maximum deviation. The deviation of the pulse coincidence of the square-wave and sampling pulses is used as the criterion for initiating switching or indicating. Critical phase differences which characterise fault cases can be detected at the latest after half a line current cycle by forming more than one square-wave pulse and more than one sampling pulse per cycle of the line current.
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