ITU-T L.9

Abstract

<strong>General</strong> <br>Metallic cable conductor terminations are installed at various locations within the cable network. The type of terminal and termination device utilized at these locations is dependent on various factors relating to the specific installation: <br>Type of cable and conductor being terminated; <br>- location and purpose of the termination; <br>- number or quantity of terminations required; <br>Type of service or transmission link involved; <br>- flexibility and protection requirements. <br>Basically, all exchange, repeater (amplifier or regenerator), and major cross-connection point terminations are of the "fixed" type utilizing wrapping, soldering of insulation displacement connection (IDC) techniques. <br>Local distribution and customer terminations utilize a mixture of "fix" and "temporary" (screw terminal) type terminations depending on individual conditions. Where required, over-voltage protection may be provided as an integral component of the terminating device or a separate "add-on" facility. <br>Within a cable network, two methods of terminating cables are available. These may generally be referred to as the direct and indirect methods. <br>Direct termination implies that the conductors associated with a particular cable connected directly to the terminal forming the "end" of the cable circuit, e.g. the cable conductor and terminal are directly coupled. <br>Indirect termination implies that the cable conductor is connected to the end terminal via a device that incorporates a preformed or manufactured termination. <br>Direct terminations are usually utilized in end terminals such as at the exchange main distribution frame (MDF) and customer premises, although some direct terminations are used in the customer distribution cable area. In most other mid-point terminations (distribution cabinets and pillars, repeater housings and termination points for trunk carrier and coaxial cables), indirect terminations utilizing devices with pre-terminating tail cables are spliced into the basic bearer cables. <br>The electric conducting parts of terminating devices will be of metal such as copper, brass or other similar alloys suitably plated to resist corrosion and other environmental effects and provide good electrical connection, either by contact, pressure, soldering or wrapping. <br>Various insulating materials (plastic extrusions and resin moulding) provide the mechanical mounting and electrical insulation of the metallic components.