| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a system and a method for automatically testing an apparatus which can automatically judge whether a relay or a breaker in grounding direction has operated normally at occurrence of grounding in a wireway. <P>SOLUTION: An apparatus automatic test system 1 is provided with a zero-phase current transformer 8 arranged at a wireway 3, a zero-phase transformer 9 which is provided in a bus 2, a relay 4 in grounding direction which is connected to the zero-phase current transformer 8 and the zero-phase transformer 9 and whose operation time is set to a fixed value, a breaker 5 which breaks the wireway 3, based on a trip signal V<SB>DG</SB>outputted from the relay 4 in grounding direction after passage of the operation time of the relay 4 in grounding direction, a stepped grounding overvoltage detector 6 which is connected to the zero-phase transformer 9 and outputs an output signal S<SB>V1</SB>which shows that the zero-phase voltage value of the bus 2 is not less than a specified value, and apparatus automatic testing means 21, 23 and 24 which judge whether the relay 4 in grounding direction and the breaker 5 are good or bad, based on the trip signal V<SB>DG</SB>of the relay 4 in grounding direction and the output signal S<SB>V1</SB>of the stepped grounding overvoltage detector 6. <P>COPYRIGHT: (C)2007,JPO&INPIT |
