| 摘要 |
PURPOSE:To shorten reconstitution at the generation of a fault on a loop transmission line by connecting a master station and plural subordinate stations as a loop by a main loop transmission line and a subloop transmission line of which transmitting directions are reversed with each other and setting up the master station at a loop back mode at normal operation. CONSTITUTION:At normal operation, the master station 1 and subordinate stations 2-a-2-d communicates with each other by the main loop 3. At the time, the master station 1 is in the loop back mode and transmits the same signal as the main loop 3 also to the subloop 4. If disconnection occurs in a point A, the local station 2-c is turned to the turnback mode by the disconnection of clocks. The local station 2-c informs the return-back mode in the self-station to the master station 1. Consequently the master station 1 turns the subordinate station 2-b to the loop back mode and also turns the self-station to the normal mode to reconstitute the loop. |
