Due to the special environment of indoor applications, indoor fiber optical cables must meet the requirements of international standards for toxicity, corrosivity and low smoke while maintaining excellent flame retardancy, mechanical properties and optical transmission characteristics. The rise of indoor fiber optical cables between floors in vertical systems, narrow space applications of communication cabinets in horizontal systems, fiber-to-desktop applications, and communication applications passing through high-pressure air-filled spaces all place different requirements on indoor fiber optical cables. How to choose the right fiber optic cable to meet the needs of different indoor applications?
At present, most indoor fiber optical cables use tight-buffered optical fibers or single-core cables as basic units, reinforced by aramid yarns, and soft optical cables with flame-retardant or non-flammable sheaths. There are also plastic optical fibers as indoor wiring fiber cables, but this product has not yet been widely used.
The tight-buffered fiber is integrated with the fiber to provide good mechanical protection, so that the fiber exhibits good compression and bending resistance when it is terminated. In addition, The tight-buffered fiber is of good flexibility and toughness,small bending radius and excellent moisture-proof function.
The good environmental protection of tight-buffered fiber can improve the service life of the fiber. The tight-buffered fiber is compatible with all standard connectors and simplifies the termination procedure and reduces the termination cost. Moreover, the tight buffer layer is easily stripped to the fiber core.
Compared with the loose tube design, the loose tube uses jelly to buffer and moisture-proof the optical fiber, while the jelly does not have fire resistance. This is far from meeting indoor fire safety requirements. Moreover, the flame spreads along the optical cable, so that the damage of the optical cable extends to the depth of the wall and deep into the pipe. During installation, a lot of cleaning materials are needed and a lot of cleaning time is spent on ointment. At the same time, a connection method is needed, which greatly increases the cost of materials. The tight-buffered optical fiber design of flame-retardant or non-flammable sheath of the indoor optical cable make the indoor optical cable fully meet the requirements of indoor safety applications.
The outer protective materials used for indoor fiber optical cables include PE, PVC, polyurethane, low-smoke halogen-free materials, flame-retardant PE, etc. indoor fiber optical cables with different outer protective materials can be used in environments with different requirements. Therefore, indoor high-performance communication transmission applications generally use indoor fiber optical cables designed with tight-buffered optical fibers.
After the indoor fiber optical cable enters the building, it is necessary to provide the connection between the entrance equipment, equipment room or computer room and the communication cabinets on different floors, which is called “vertical wiring system”. At this time, the wiring fiber cables are mostly located in the riser in the vertical shaft between the floors. For this reason, the indoor fiber optical cable needs to withstand greater tensile force (self-weight maximum).
This article comes from unitekfiber edit released