How to prevent lightning damage in optical fiber and cable wiring?

With the development of the network, optical fiber, as a medium used to transmit data in the integrated wiring system, is increasingly used by people because it has the advantages of large transmission rate and long distance. As we all know, the optical fiber is non-conductive and can be protected from impact current. The optical cable also has good protection performance. The metal components in the optical cable have a high insulation value to the ground, and the lightning current is not easy to enter the optical cable, however, because the optical cable has a reinforced core, especially the directly buried optical cable has an armored layer, when the optical cable line is struck by lightning, the optical cable can also be burned or damaged. Today, I would like to explain in detail the main measures for lightning protection of optical cables and fibers in the construction of integrated wiring projects. Measures 1. Lightning protection for direct optical cable lines: ① internal grounding mode, the metal parts in the optical cable should be connected at the joint position, keep the reinforced core, moisture-proof layer and armor layer of the relay section optical cable connected. (2) According to YDJ14- According to the regulation of 91, the moisture-proof layer, armored layer and reinforced core at the joint of the optical cable should be electrically disconnected, and all of them are not grounded and are insulated to the ground, which can avoid the accumulation of induced lightning current in the optical cable, it can also avoid the lightning current in the Earth from the grounding device to the optical cable due to the difference of the impedance between the lightning protection discharge line and the optical cable metal components to the ground loop. Measures 2. For overhead optical cables: overhead suspension cables should be electrically connected and grounded every 2km. When grounding, they can be directly grounded or grounded through appropriate surge protection devices. In this way, the suspension wire has the protective effect of overhead ground wire. Measure 3. After the optical cable enters the terminal box, the terminal box should be grounded. After the lightning current enters the metal layer of the optical cable, the grounding of the terminal box can quickly discharge the lightning current and play a protective role. The directly buried optical cable is adopted with armored layer and reinforced core, and the outer sheath is PE (Polyethylene)Sheath, can effectively prevent corrosion and mouse bite.