| 摘要 |
PURPOSE:To indicate operation of a relay reliably even for short duration of relay output, by indicating the operation on condition that an output is provided from a fault judging circuit by operation of the relay and a trip signal is outputted. CONSTITUTION:When a relay 1 produces an output, an operational command is sent from a fault judging circuit 5 to an output relay 6 and an AND gate 22 produces an output to set relay operation holding circuits 25, 28. Then the output relay 6 functions to operate a trip relay 7 which provides a trip command to a circuit breaker. When the contact 7a of the trip relay 7 closes, an interface circuit 8 produces an output then an AND gate 9 produces an output and an operation indicating/holding circuit 12 is set to light an indicator 15. Since an AND gate 18 produces an output similarly, an external alarm indication relay 20 operates based on an output fed from a one-shot circuit 19. |
