| 摘要 |
<p>PURPOSE:To detect and obtain information from an optional steel tower part through a sensor, etc., by disconnecting the overhead earth wire of a jumper part, replacing a right- and a left-side optical cable with a long-sized cable and providing an excessive-length part, and leading and connecting the cable in and to an optical cable connection box through a watertight connection part. CONSTITUTION:The overhead earth wire 2 is extended among >=3 steel towers and jumper parts 2A of the overhead earth wire 2 are formed between steel towers. The overhead earth wire 2 of the jumper part 2A of, for example, a steel tower 1A is cut at its nearly center part and existent optical cables 9 are led out from the right and left overhead earth wires 2 to insert new optical cables 12 with extra length respectively. Then, the metallic pipe 8 of the overhead earth wire 2 and an end part of a protection pipe which is set up are connected mutually through a watertight structure part and a protection pipe 8 and the extra-length part of the optical cable 12 inserted into it are led in the optical fiber cable connection box 3C to form a lead-out part at the steel tower position of the optical fiber.</p> |
