METHOD AND EQUIPMENT FOR SENSING FAULT OF ELECTRIC SYSTEM

摘要

PURPOSE:To decide whether a fault of an electric system is generated on a primary side or on a secondary side, by sensing the varying part varied suddenly from the stationary value of an electric signal, and concurrently, by deciding the polarity of the varying part. CONSTITUTION:A first waveform-shaping circuit 9 for outputting the rectangular wave having the same polarity as a signal S0 and a second waveform-shaping circuit 10 for outputting the rectangular wave having the same polarity as the converted part of the signal S0 are provided respectively. Further, a polarity deciding circuit 11 for deciding the polarities of the two rectangular waves outputted by the respective waveform-shaping circuits 9, 10 and for outputting the decided results thereof is provided.