Overview

Telecommunications cabling installers must be aware of the various types of media (cable) that are available for installation and maintenance. Each type and configuration has specific uses and defined methods that must be employed during installation. This section focuses on horizontal media, although backbone cable is also identified.

This document addresses the various types of telecommunications cable commonly in use. The major telecommunications cables are:

• Twisted-pair copper cable:

  Proposed Category 6

  Category 5e

  Category 5

  Category 3

• Enhanced shielded twisted-pair (STP) copper cable.

• Coaxial cable:

  Thin Ethernet IEEE 802.3

  Thick Ethernet IEEE 802.3

  Series-11 backbone, Series-6 horizontal drop, and Series-59 patch cord

  Series-62

• Optical fiber cable:

  Multimode (50/125 m)

  Multimode (62.5/125 m)

  Singlemode

Twisted-pair copper cable

Twisted-pair copper cable has been used for a long time for both voice and data cabling. It has the following characteristics:

• Composed of pairs of wires twisted together

• Commonly available in various pair counts (2 2400 pairs)

• Normally not shielded below 600 pairs and has an overall aluminum-steel shield up to 2400 pairs

• Reduces electrical interference by twisting of conductors

• Characteristic impedance of 100 ? at 100 MHz and 600 W at 16 MHz

• Recommended conductor sizes 22 AWG [0.64 mm (0.025 in)] 24 AWG [0.51 mm (0.020 in)]

Figure 1.23: Typical twisted-pair cable.

To improve information throughput, significant performance improvements have been made to unshielded twisted-pair (UTP) cable. In ANSI/TIA/EIA-568-A, Commercial Building...