| 摘要 |
PURPOSE:To prevent the operation of unnecessary alarm and lamp display, by stopping the operation of an external monitor automatically when the system is switched to a simple spare device. CONSTITUTION:When a processor 5 detects a failure of the system not possible for exchange operation, a simple spare device changeover switch 11 is driven, a K relay 10 is activated, its contact k1 is controlled to switch the connection between an incoming trunk device 1 and an outgoing trunk 2 by a simple spare device 9. Further, a brake contact k2 of the k relay 10 turn-off ground required for the operation of an external monitor 6. Thus, when the exchange system is switched to the device 9 due to any cause, since the operation of the device 6 is stopped, allowing to prevent the operation of unnecessary alarm and lamp display. |
