Fiber-Optic Network Components DIGITUS Optical fiber cable Construction of a glass fiber cable The glass fiber core A glass fiber cable consists mainly of three parts: The glass fiber There are various thicknesses of the glass fiber core which are core, carrying the light signal, the glass jacket which reflects the described with their cross section: The single mode fiber cable with light and a plastic cladding which protects the glass fiber cable from a cross section of 9m and multi-mode fiber cables with cross sec - external influences and makes it flexible tions of 50 m and 62.5 m. Single mode fiber cables are more costly than multi-mode fiber cables because of difficulties in the manufacture of an extremely thin cable with a cross section of 9m, but they have a greater range. Additional designations are used to describe them in terms of their quality: OS1 and OS2 for single mode fiber cables, where OS2 is the best quality and OM1, OM2 and OM3 for multi-mode cables where OM3 is the best quality. Fiber-Optic Patch Cables ................................................................. 75 Fiber-Optic Couplers and Connectors ............................................. 81 Fiber-Optic Installation cable ........................................................... 79 Fiber-Optic Spliceboxes.................................................................... 82 Fiber-Optic Pigtails ........................................................................... 80 Fiber-Optic Accessories .................................................................... 86The difference between single mode and multi mode The combined strand type represents an intermediate form of the The light is reflected in a zigzag pattern in the core of thicker multi- solid core type and the hollow core type. The hollow space of the mode fiber cables. This results in higher attenuation, the range of cladding is filled here with a gel or similar. the signal reduces, in other words. The light does not refract so frequently in single mode fiber cables and guarantees an enor - Use of the individual glass fiber cables mous range. Multi fire cables are usually found in cabling in buildings and in short and medium distance runs. OM2 fiber cables are used the most. OM3 fibers of better quality are used more and more fre - quently and replace OM2 fiber cables over the long run. Single mode fiber cables are used because of their good signal properties in long distance cabling. LWL plugs The widest distributed LWL plugs are ST-, SC- and LC plugs. The LC Cladding plugs gains an ever increasing share of the market for glass fiber There are several forms of cladding for glass fiber cables. plugs because of the compact size and their use with mini GBIC modules in switches or media converters. Pigtails Pigtails are cables equipped with an LWL plug on one side and a plain glass fiber cable on the other side. They are used at the end points of laid cables and are spliced with each other. Solid strand type Hollow strand type Combined strand type Splicing Splicing is understood to be the connection of two glass fiber The solid strand type surrounds the fiber directly. This has a disad - cables. These are adjusted at their end points and permanently vantageous effect when there is high strain and with temperature fused together. differences. Unlike the solid strand type, the hollow strand type does not surround the fiber directly. There is a hollow space between the cladding and the fiber which reduces the disadvantageous effects of strain load and temperature differences. Kabeltyp A Outside cable I/J Inside cable U optoversal cable (not VDE) Uniform, abbreviated descriptions exist for LWL Ader cables in accordance with DIN-VDE Norm 0888 V Solid strand which consist of a series of number, as can be D Bundled strand W Hollow strand, filled seen in the table. H Hollow strand, unfilled M Mini bundle (not VDE) S Metallic distribution element F Filling compound for filling the cord cavities in the cable core Q Source element (not VDE) 1. Outside cladding H LSOH cladding Y PVC cladding 2Y PE cladding (ZN)2Y PE cladding with non-metallic strain relief elements (ZN)(L)2Y PE laminated cladding with non-metallic strain relief elements (ZN)(SR)2Y Steel spiral laminated cladding with non-metallic strain relief elements 2. Outside cladding B Reinforcement BY Reinforcement with PVC protective cover B2Y Reinforcement with PE protective cover Number of fibers Number of bundled fibers x number of fibers per fiber bundle 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Construction LG stranding in layers Bandwidth in MHz for 1 km (Multimode fibers) Dispersion in ps/nm x km (Single mode fibers) Wavelengths B 850nm (multimode fibers) F 1300nm (multimode fibers) F 1310nm (single mode fibers) H 1550nm (single mode fibers) Attenuation coefficient in dB/km Cladding diameter in m (125m) Field diameter in m for single mode fibers (9m) Core diameter in m for multi mode fibers (50m or 62.5m) Construction type E Single mode fiber Subject to alterations. G Multimode fiber 4