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Network Cabling Solutions Appendix Q Quick Clip An electrical contact used to provide an insulation displacement connection to telecommunications cables. R Raceway See Pathway Return Loss Noise or interference caused by impedance discontinuities along the transmission line at various frequencies. Return loss is expressed in decibels. Ring Conductor A telephony term used to describe one of the two conductors in a cable pair used to provide telephone service. This term was originally coined from its position as the second (ring) conductor of a tip-ring-sleeve switchboard plug. Tip Conductor A telephony term used to describe the conductor of a pair that is grounded at the central office when the line is idle. This term was originally coined from its position as the first (tip) conductor of a tip-ring-sleeve switchboard plug. Topology The physical or logical layout of links and nodes in a network. These include star, ring and bus configurations. Transfer Impedance A measure of shield effectiveness. Transition Point (TP) A location in the horizontal cabling subsystem where flat undercarpet cabling connects to round cabling. Transverse Conversion Transfer Loss (TCTL) A ratio of the measured common mode voltage on a pair relative to the differential mode voltage applied at the opposite end of the same pair, or on either end of another pair, expressed in dB. S Screen An element of a cable formed by a shield. Shield A metallic layer placed around a conductor or group of conductors. Star Topology 1. A method of cabling each telecommunications outlet/connector directly to a cross connect in a horizontal cabling subsystem. 2. A method of cabling each cross connect (HC and IC) to the main cross connect (mC) in a backbone cabling subsystem. Surge A rapid rise in current or voltage usually followed by a fall back to a normal level. Also referred to as transient. T Telecommunications Any transmission, emission or reception of signs, signals, writings, images, sounds or information of any nature by cable, radio, visual, optical or other electromagnetic systems. Trunk A communication line between two switching systems. The term "switching systems" typically includes equipment in a central office (the telephone company) and PBXS. A tie trunk connects PBXS. Central office trunks connect a PBX to the switching system at the central office. U Unshielded Twisted Pair (UTP) A cable with multiple pairs of twisted insulated copper conductors bound in a single sheath. W Work Area The area where horizontal cabling is connected to the work area equipment by means of a telecommunication outlet. A station/desk which is served by a telecommunications outlet. Sometimes referred to as a "work station". Work Area Cable A cable assembly used to connect equipment to the telecommunications outlet in the work area. Work area cables are considered to be outside the scope of cabling standards. Telecommunications Room (TR) An enclosed space for housing telecommunications equipment, cable terminations and cross-connect cabling used to serve work areas located on the same floor. The telecommunications room is the typical location of the horizontal cross-connect and is considered distinct from an equipment room because it is considered to be a floor serving (as opposed to building or campus serving) facility. Telecommunications Industry Association (TIA) An organization that sets standards for cabling, pathways, spaces, grounding, bonding, administration, field testing and other aspects of the telecommunications industry. 228 For product information visit www.hellermann.tyton.com or call 800.537.1512