164 Technical Information Electronics Random Winding: A winding in rotating equipment wherein the wires do not lie in an even pattern. Reactance: The opposition offered to the flow of alternating current by inductance or capacitance of a compound or circuit. Red Plaque: A powdery, brown-red growth found on silvercoated copper conductors and shield braids. Redraw: The consecutive drawing of wire through a series of dies to reach a desired wire size. Reducing Joint: A joint between two lengths of cable where the conductors are not the same size. Reel: A revolvable flanged device made of wood or metal, used for winding flexible metal wire or cable. Reflection: (fiber optic) Change in direction of a light wave or ray. Reflection Loss: The part of a signal which is lost due to reflection of power at a line discontinuity. Refraction: (fiber optic) The bending of lightwaves or rays as they go from one material to another due to the difference in velocities in the materials. Reinforced Sheath: The outermost covering of a cable that has cable sheath constructed in layers with the addition of a reinforcing material, usually a braided fiber, molded in place between layers. Remanence: The magnetic induction that remains in a magnetic circuit after the removal of an applied magnetomotive force. Repeater: A device which consists of a transmitter and a receiver or transmitter, used to regenerate a signal to increase the system transmission length. Resistance: A measure of the difficulty in moving electrical current through a medium when voltage is applied. It is measured in Ω. Resistive Conductor: A conductor with high electric resistance. Retractile Cord: A cord having specially treated insulation or jacket so that it will retract. Return Wire: A ground wire or the negative wire in a direct-current circuit. Ribbon Cable: A flat cable of individually insulated conductors lying parallel and held together by means of adhesive or woven textile yarn. Ridge Marker: One or more ridges running laterally along the outer surface of a plastic- insulated wire for purposes of identification. Rigid Bay: Cabling equipment that maintains component sequence, and can produce cables with distinct layers. Rigid Coaxial Cable: Nonflexible coaxial cable, usually a metal tube armored coaxial cable. Ring Tongue: A solderless terminal that connects wire to a stud. Ringing Out: Locating or identifying specific conductive paths by passing current through selected conductors. Rip-Cord: 1.) Two or more insulated conductors in a parallel configuration which may be separated to leave the insulation of each conductor intact. 2.) A small filament cord used to rip through the outer cable sheath. RoHS (Restriction on Hazardous Substances): European Union directive that restricts use of heavy metal substances. Rope Concentric: A group of standard conductors assembled in a concentric manner. Rope Lay Conductor: A conductor composed of a central core surrounded by one or more layers of helically laid groups of wires. Rope Unilay: A group of stranded conductors assembled in a unilay manner. Round Wire Shields: Shields constructed from bare, tinned or silver-plated copper wire that include braided, spiral and reverse spiral. Routers: A device that determines how to forward a packet toward its destination, based on tables that indicate the costs, congestion status and other factors associated with possible routes. Also called a level 3 relay or an intermediate system. Rubber (Wire Insulation): Term used to describe wire insulations made of thermosetting elastomers; occurs naturally or may be made synthetically. Rulan®: DuPont’s trade name for their flame- retardant polyethylene insulating material. Screen: A shield placed over the entire core. Secondary Insulation: A nonconductive material that protects the conductor against abrasion and provides a second electrical barrier. Segmental Conductor: A stranded conductor consisting of three or more stranded conducting elements, each element having approximately the shape of the sector of a circle, assembled to give a substantially circular cross-section. Selenium Cure: Process used to cure neoprene and rubber jacketed wires and cables. Self-Extinguishing: Characteristic of a material whose flame is extinguished after the igniting flame source is removed. Semi-Conducting Jacket: A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential. Semi-Rigid: A cable containing a flexible inner core and a relatively inflexible sheathing. Semi-Solid: An insulation cross-section having a partially open space between the conductor and the insulation perimeter. Separator: A layer of insulating material which is placed between a conductor and its dielectric between a cable jacket and the components it covers, or between various components of a multiple-conductor cable. Series Circuit: A circuit in which the components are arranged end to end to form a single path for current. Serve: A filament or group of filaments such as fibers or wires, wound around a central core. Serving: A wrapping applied over the core of a cable or over a wire. Sheath: See Cable Sheath. Shield: In cables, a metallic layer placed around a conductor or group of conductors to prevent electrostatic or electromagnetic interference between the enclosed wires or external fields. Shield Coverage: Amount of outer cable covered by the shielding material. Shield Effectiveness: The ability of a shield to screen out undesirable signals. Shielded Line: A transmission line whose elements confine propagated radio waves to an essentially finite space inside a tabular conducting surface called the sheath, thus preventing the line from radiating radio waves. Shielded-Type Cable: A cable in which the surface of the insulation is at ground potential. Shunt Wire: A conductor joining two parts of an electric circuit to divert part of the current. Signal: A current used to convey information, either digital, analog, audio or video. Silicone: A material made from silicon and oxygen. Can be in thermosetting elastomer or liquid form. The thermosetting elastomer form is noted for high heat resistance. Silicone Treating: A silicone liquid treatment applied to insulated conductors to allow for easy jacket stripping. Sine Wave: A wave that can be expressed as the sine of a linear function of time, or space or both. Single-ended: Unbalanced, such as grounding one side of a circuit or transmission line. Single-Faced Tape: Fabric tape finished on one side with a rubber or synthetic compound. Singlemode Fiber: A fiber wave guide in which only one mode will propagate. The fiber has a very small core diameter of approximately 8mm. It permits signal transmission at extremely high bandwidths and is generally used with laser diodes. Sizing: Applying a material to a surface to fill pores. Skeleton Braid: Widely separated braid of fiber copper or steel, used to hold core together, for reinforcing jacket or for shielding. Skew Rays: A ray that does not intersect the fiber axis. Generally, a light ray that enters the fiber core at a very high angle. Skim Tape: Filled tape coated on one or both sides with a thin film of uncured rubber or synthetic compound to produce a coating suitable for vulcanization. Skin Effect: The tendency of alternating current, as its frequency increases, to travel only on the surface of a conductor. Sleeve: A braided, knitted or woven tube used over wires or components as insulation tubing. Also called Sleeving. Solid Conductor: A conductor consisting of a single wire. Source Coupling Loss: (fiber optic) Loss of light intensity as light from source passes into fiber. Space, Telecommunications: An area used for housing the installation and termination of telecommunications equipment and cable, e.g. telecommunications closets, work areas and manhole/handholes. Span: (1.) In flat conductors, distance between the reference edge of the first and the last conductor. (2.) In round conductors, distance between centers of the first and last conductors. (3.) In aerial cable, the distance between poles or support clamps. Spark Test: A test designed to locate pin-holes in the insulation of a wire or cable by application of a voltage for a very short period of time while the wire is being drawn through the electrode field. Specific Gravity: The ratio of the density (mass per unit volume) of a material to that of water. Spectral Bandwidth: The difference between wavelengths at which the radiant intensity of illumination is half its peak intensity. Spectral Response: (fiber optic) The response of a detector (or a system) over different wavelengths. Spectrum: Frequencies that exist in a continuous range and have a common characteristic. Speed of Light (c): 2.998 x 108 meters per second. Spiral Shield: A metallic shield of fine-stranded wires applied spirally rather than braided. Glossary
