Structured wiring . It consists of laying cables inside a building for the purpose of establishing a local area network. It is usually a copper twisted pair cable, for IEEE 802.3 type networks. However, it can also be fiber optic or coaxial cable .
Summary
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- 1 Importance
- 2 Structured wiring system
- 3 Limitations
- 1 Connection
- 4 Main elements
- 1 Horizontal cable and connecting hardware
- 2 Routes and Horizontal Spaces
- 5 Design considerations
- 1 Topology
- 2 Distances
- 3 Recognized means
- 6 Vertical wiring
- 7 Telecommunications room
- 8 Service entrance room
- 9 Grounding system
- 10 Attenuation
- 11 Capacitance
- 12 Impedance and delay distortion
- 13 American Structured Cabling Standards
- 14 See also
- 15 Sources
Importance
It is the collective system of cables , pipes , connectors , labels , spaces and other devices that must be installed to establish a generic telecommunications infrastructure in a building or campus.
The characteristics and installation of these elements must be done in compliance with standards to qualify as structured cabling. The adherence of standards-structured cabling facilities brings with it the benefits of provider and protocol independence (generic infrastructure), installation flexibility, growth capacity, and ease of administration.
Structured cabling system
It is the cable infrastructure destined to transport, throughout the length and breadth of a building, the signals emitted by a transmitter of some type of signal to the corresponding receiver. A structured cabling system is physically a single, complete cable network, with combinations of copper wire (UTP unshielded twisted pairs), fiber optic cables, connection blocks, cables terminated in different types of connectors and adapters. One of the benefits of structured cabling is that it allows for easy and systematic management of moves and relocations of people and equipment. The building telecommunication cabling system supports a wide range of telecommunication products without modification. It is possible to design the wiring of a building with very little knowledge of the telecommunication products that will then be used on it. The standard guarantees that the systems executed according to it will support all present and future telecommunications applications for a period of at least ten years. This statement may seem excessive, but not, considering that among the authors of the standard are precisely the manufacturers of these applications.
Limitations
The laying involves a certain complexity when it comes to covering large areas such as a multi-storey building. In this sense, the design limitations imposed by the local area network technology to be implemented must be taken into account:
- Segmentation of networktraffic .
- The maximum length of each network segment.
- The presence of electromagnetic interference.
- The need for virtual local networks.
Conection
- Run cables on each floor of the building.
- Interconnect cables each floor.
Main elements
The EIA / TIA 568A standard defines horizontal cabling as follows : The horizontal cabling system is the portion of the telecommunications cabling system that extends from the work area to the telecommunications room or vice versa. Horizontal cabling consists of two basic elements:
Horizontal cable and connecting hardware
They provide the basic means of transporting telecommunications signals between the work area and the telecommunications room. These components are the “contents” of the routes and horizontal spaces.
Routes and Horizontal Spaces
Horizontal routes and spaces are used to distribute and support horizontal cable and connect hardware between the work area exit and the telecommunications room. These routes and spaces are the “containers” of the Horizontal cabling.
- If there is a suspended ceiling, the use of gutters is recommended to transport the horizontal cables.
- One ¾ in pipe for every two UTP cables.
- One 1in pipe for each two fiber optic cable.
- The minimum radii of curvature must be well implemented.
Design considerations
The costs in materials, labor and interruption of work when making changes in the horizontal wiring can be very high. To avoid these costs, horizontal cabling must be capable of handling a wide range of user applications. The horizontal layout should be designed to facilitate maintenance and relocation of work areas. The designer should also consider incorporating other building information systems (eg cable television , environmental monitoring, security, audio, alarms, and sound) when selecting and designing horizontal cabling.
Topology
The EIA / TIA 568A standard makes the following recommendations regarding the topology of horizontal cabling: Horizontal cabling must follow a star topology. Each telecommunications socket / connector in the work area must be connected to an interconnect in the telecommunications room.
Distances
Regardless of the physical environment, the maximum horizontal distance should not exceed 90m. The distance is measured from the mechanical termination of the medium at the horizontal interconnect in the telecommunications room to the telecommunications socket / connector in the work area. In addition, the following distances are recommended: 10 m are separated for cables in the work area and cables in the telecommunications room (patch cords, jumpers, and equipment cables).
Recognized means
Three types of cables are recognized for the horizontal cabling system:
- Four-pair 100 ohm Unshielded Twisted Pair (UTP) cables.
- Four-pair 150 ohm shielded twisted pair (STP) cables.
- 5 / 125 um multimode fiber optic cables and two fibers.
Vertical wiring
The purpose of backbone cabling is to provide interconnections between building service entry rooms, equipment rooms, and telecommunications rooms. Backbone cabling includes the vertical connection between floors in multi-story buildings. Backbone cabling includes transmission media (cable), main and intermediate cross-connect points, and mechanical terminations. Vertical cabling makes the interconnection between the different telecommunication cabinets and between these and the equipment room. In this component of the cabling system, it is no longer economical to maintain the general structure used in horizontal cabling, but it is convenient to carry out independent installations for telephony and data. This is reinforced by the fact that, if it is necessary to replace the backbone, this is done at a relatively low cost, and causing very little inconvenience to the occupants of the building. The telephone backbone is usually done with a multipair telephone cable. To define the data backbone it is necessary to take into account what the physical layout of the equipment will be. Normally, the physical laying of the backbone is in the form of a star, that is, the cabinets are interconnected with one that is defined as the center of the star, where the most complex electronic equipment is located. To define the data backbone it is necessary to take into account what the physical layout of the equipment will be. Normally, the physical laying of the backbone is in the form of a star, that is, the cabinets are interconnected with one that is defined as the center of the star, where the most complex electronic equipment is located. To define the data backbone it is necessary to take into account what the physical layout of the equipment will be. Normally, the physical laying of the backbone is in the form of a star, that is, the cabinets are interconnected with one that is defined as the center of the star, where the most complex electronic equipment is located.
The data backbone can be implemented with UTP cables or with fiber optics. In the case of deciding to use UTP, it will be category 5 and a number of cables will be arranged from each cabinet to the cabinet selected as the star center.
Standard 19-inch-wide cabinets with doors are used, approximately 50 cm deep and between 1.5 and 2 meters high. The following sections are generally available in such cabinets:
- Workstation connection:2 UTP cables arrive from each workstation.
- Telephone backbone connection: multipaircable that can be determined in connection strips or “patch panels”.
- Data backbone connection:fiber optic cables that are led to a suitable connection tray.
- Electronic data network:Hubs, Switches, Breidges and other necessary devices.
- Power supply for such devices.
- Internal lighting to facilitate carrying out work in the cabinet.
- Ventilation to keep the internal temperature within acceptable limits.
Telecommunications room
It is an exclusive area within a building where the telecommunications equipment is housed. Its main function is the completion of the horizontal and vertical wiring of the building. Equipment cable connections to horizontal or vertical cabling can be interconnects or cross connections. They must be designed in accordance with TIA / EIA-569 .
Services entrance room
It consists of cables, connection accessories, protection devices, and other equipment necessary to connect the building to external services. It can contain the demarcation point. They offer electric protection established by electric available codes. They must be designed according to the TIA / EIA-569 – A standard . The installation requirements are:
- Cable handling precautions
- Avoid strains on the cable
- Cables should not be routed in tight groups
- Use appropriate cable paths and accessories 100 ohms UTP and ScTP
- Do not turn with an angle of May at 90 degrees
Grounding system
The grounding and bridging system established in ANSI / TIA / EIA-607 standard is an important component of any modern structured cabling system. The cabinet must have a ground connection, connected to the general ground of the electrical installation, to make the connections of all equipment. The ground conduit is not always indicated on plans and may be unique for branches or circuits that pass through the same pass boxes, conduits or trays. Safety ground wires will be grounded underground.
Attenuation
Transmission signals over long distances are subject to distortion, which is a loss of signal strength or amplitude. Attenuation is the main reason that the length of nets has various restrictions. If the signal becomes too weak, the receiving equipment will not intercept well or will not recognize this information. This causes errors, poor performance when having to transmit the signal. Repeaters or amplifiers are used to extend the distances of the network beyond the limitations of the cable. Attenuation is measured by devices that inject a test signal at one end of the cable and measure it at the other end.
Capacitance
Capacitance can distort the signal in the cable, the longer the cable, and the thinner the insulation, the greater the capacitance, resulting in distortion. Capacitance is the unit of measurement for the energy stored in a cable. Cable testers can measure the capacitance of this pair to determine if the cable has been threaded or stretched. The capacitance of the twisted pair cable in the networks is between 17 and 20 pF.
Impedance and delay distortion
Transmission lines will have background noise somewhere, generated by external sources, the transmitter or adjacent lines. This noise is combined with the transmitted signal. The resulting distortion may be less, but the attenuation may cause the digital signal to drop to the level of the noise signal. The level of the digital signal is higher than the level of the noise signal, but it approaches the level of the noise signal as you get closer to the receiver. A signal made up of multiple frequencies is prone to delay distortion caused by impedance, which is the resistance to change of different frequencies. This can cause the different frequency components that contain the signals to reach the receiver out of time. If the frequency increases, the effect worsens and the receiver will be unable to interpret the signals correctly. This problem can be solved by decreasing the length of the cable. Note that the measurement of the impedance helps us to detect cable breaks or missing connections. The cable must have an impedance of 100 ohm at the frequency used to transmit data. It is important to maintain a signal level above the noise level. The biggest source of noise in multi-wire twisted pair cable is interference. Interference is a break in adjacent cables and is not a typical cable problem. Environmental noise in digital circuits is caused by fluorescent lamps, motors, microwave ovens, and office equipment such as computers, fax machines, telephones, and copiers.
American Structured Cabling Standards
- TIA-526-7 “Measurement of Optical Power Loss of Installed Single-Mode Fiber Cable Plant” – OFSTP-7 – (February 2002)
- TIA-526-14-A Optical Power Loss Measurements of Installed Multimode Fiber Cable Plant – OFSTP-14 – (August 1998)
- ANSI / TIA / EIA-568-B.1 on Telecommunications Wiring for Commercial Buildings, Part 1: General Requirements, May 2001.
- ANSI / TIA / EIA-568-B.1-1-2001 Addendum, Addendum 1, Minimum Bend Radius for 4 Pair UTP and STP Cables, July 2001.
- TIA / EIA-568-B.1-2 Commercial Building Telecommunications Cabling Standard Part 1: General Requirements Addendum 2 – Grounding and Bonding Requirements for Screened Balanced Twisted-Pair Horizontal Cabling – (February 2003)
- TIA / EIA-568-B.1-3 Commercial Building Telecommunications Cabling Standard Part 1: General Requirements Addendum 3 – Supportable Distances and Channel Attenuation for Optical Fiber Applications by Fiber Type – (February 2003)
- TIA / EIA-568-B.1-4 Commercial Building Telecommunications Cabling Standard Part 1: General Requirements Addendum 4 – Recognition of Category 6 and 850 nm Laser Optimized 50/125 μm Multimode Optical Fiber Cabling – (February 2003)
- TIA / EIA-568-B.1-5 Commercial Building Telecommunications Cabling Standard Part 1: General Requirements Addendum 5 – Telecommunications Cabling for Telecommunications Enclosures – (March 2004) oe xvpemenn la ratta mierd sapos
- TIA / EIA-568-B.1-7 Commercial Building Telecommunications Cabling Standard Part 1: General Requirements Addendum 7 – Guidelines for Maintaining Polarity Using Array Connectors – (January 2006)
- TIA / EIA-568-B.2 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – (December 2003)
- TIA / EIA-568-B.2-1 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 1 – Transmission Performance Specifications for 4-Pair 100 ohm Category 6 Cabling – (June 2002)
- TIA / EIA-568-B.2-2 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 2– Revision of Sub-clauses – (December 2001)
- TIA / EIA-568-B.2-3 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 3– Additional Considerations for Insertion Loss & Return Loss Pass / Fail Determination – (March 2002)
- TIA / EIA-568-B.2-4 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 4 – Solderless Connection Reliability Requirements for Copper Connecting Hardware – (June 2002)
- TIA / EIA-568-B.2-5 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 5 – Corrections to TIA / EIA-568-B.2 – (January 2003)
- TIA / EIA-568-B.2-6 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 6 – Category 6 Related Component Test Procedures – (December 2003)
- TIA / EIA-568-B.2-11 Commercial Building Telecommunications Cabling Standard Part 2: Balanced Twisted-Pair Cabling Components – Addendum 11 – Specification of 4-Pair UTP and SCTP Cabling – (December 2005)
- TIA / EIA-568-3 Optical Fiber Cabling Components Standard – (April 2002)
- TIA / EIA-568-3.1 Optical Fiber Cabling Components Standard – Addendum 1 – Additional Transmission Performance Specifications for 50/125 μm Optical Fiber Cables – (April 2002)
- TIA-569-B Commercial Building Standard for Telecommunications Pathways and Spaces – (October 2004)
- TIA-598-C Optical Fiber Cable Color Coding – (January 2005)
- TIA / EIA-606-A Administration Standard for Commercial Telecommunications Infrastructure – (May 2002)
- J-STD-607-A Commercial Building Grounding (Earthing) and Bonding Requirements for Telecommunications – (October 2002)
- TIA-758-A Customer-owned Outside Plant Telecommunications Infrastructure Standard – August 2004
