| 摘要 |
PURPOSE:To swiftly detect a fault in a transmission line, by inverting a transmission route in accordance with a command from a supervisory station, and sending back a status from the communication station which has been designated by the supervisory station. CONSTITUTION:The synchronizing station 10 becomes a supervisory station which takes charge of centralized system supervision, and in case when a fault has occured on the transmission line, both a transmission route inversion command and a status send-back command with station designation are sent out to all the communication stations 11-ab. The communication station 11 switches the switch SW1 and SW2, and also sends back the status. The synchronizing station 10 detects an abnormal transmission line by detecting whether the status has been sent back or not from the designated station. |
