| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a communication time and reduce a locating time. <P>SOLUTION: A waveform recorder 20 comprises: a change detection unit 60 for detecting whether there is a change in a voltage and a current in each phase; first recording control means 50 for controlling a recording unit 45 to record waveform data of the voltage and the current before and after the occurrence time when the change occurred; determination means 50 for performing first determination whether a zero-phase current exceeds a first threshold H1 in a determination time period and second determination whether every voltage of three phases becomes less than a second threshold in the determination time period; and second recording control means 50 for controlling the recording unit 45 to record determination information indicating the determination by the determination means 50 in association with the waveform data. <P>COPYRIGHT: (C)2013,JPO&INPIT |
