Optical Fiber Cabling
The specifications for optical fiber cabling consist of one recognized cable type for the horizontal subsystem and two cable types for the backbone subsystem:
- Horizontal - 62.5/125 µm multimode (two fibers per outlet).
- Backbone - 62.5/125 µm multimode or single mode.
All optical fiber components and installation practices shall meet applicable building and safety codes.
Optical Fiber Cables:
- Cables shall be marked according to applicable electrical codes.
- Horizontal cables shall contain a minimum of 2 fibers (typically 6 or 12 fiber cables are used for backbone cabling).
- For multimode, 62.5/125 µm, graded index is specified.
- For single mode, a 8.7-10 µm dispersion unshifted core with 125 µm cladding is specified.
Optical Fiber Patch Cords:
- Shall be a two-fiber indoor cable of the same type as the cables they connect to.
- Shall allow for easy connection and reconnection and ensure that polarity is maintained (568SC configuration required).
- Shall perform a cross-over of fiber positions A and B. If provided in simplex form, ends shall be identified "A" and "B".
Optical Fiber Cabling Installation:
- Testing is recommended to ensure correct polarization and acceptable link performance. An informative annex is provided for optical fiber link performance.
Installation of Optical Fiber Connecting Hardware:
- Connectors shall be protected from physical damage and moisture.
- Distribution facilities for optical fiber should terminate no more than 144 optical fibers per 14 rack spaces [622 mm (24.5 in.)] or 2 ft. x 2 ft. wall space.
- Capacity for 12 or more fibers per rack space [44.5 mm (1.75 in.)] should be provided.
- Optical fiber connecting hardware shall be installed:
- To provide well organized installation with cable management.
- In accordance with manufacturers' guidelines.
Optical Fiber Connections:
Recommended adapter (coupler) and connector is designated as 568SC (duplex SC). ST connectors are allowed, where an installed base exists.
In cross-connects, a simplex or duplex connector is allowed.
For the work area side of the telecommunications outlet, the 568SC duplex SC connector is specified. 568SC patch cords are required for two-fiber applications.
Outlets shall be securely mounted at planned locations.
The two positions in a duplex connector are referred to as "position A" and "position B".
The outlet shall have:
- The ability to secure optical fibers.
- Cable management means to ensure a minimum bend radius of 30 mm (1.18 in.).
- The ability to store at least 1 m (3.28 ft.) of optical fiber cable.
Identification of fiber types:
- Multimode connectors and adapters shall be beige in color.
- Single mode connectors and adapters shall be blue in color
568SC connectors are rated for a minimum of 500 mating cycles.
The 568SC adapter performs a cross-over between position A and position B of two mated connectors.
Unterminated fibers shall be stored in a telecommunications outlet box.
|