--- Term Definition
A --- Ampere
ABR --- Available Bit Rate.
Abrasion Resistance --- Ability of a wire, cable or material to resist surface wear.
Abrasion Stripper ---More accurately described as "buffing stripper", which is a motorized device for removing flat cable insulation by means of one or two buffing wheels that melt the insulation and brush it away from the conductors.
AC --- Alternating current. Electric current that alternates or reverses polarity in a cyclical manner (e.g. 60 Hertz AC power)
Accelerated Aging --- A tes tthat simulates long time environmental conditions in a relatively short time.
ACR --- Attenuation Cross talk Ratio. The difference between attenuation and crosstalk, measured in dB, at a given frequency. Important characteristic in networking transmission to assure that signal sent down a twisted pair is stronger at the receiving end of the cable than are any interference signals imposed on that same pair by crosstalk from other pairs.
ADSL--- Asymmetric Digital Subscriber Line
AES/EBU--- Informal name of a digital audio standard established jointly by the AES (Audio Engineering Society) and EBU (European Broadcast Union) organizations.
AF --- Audio frequency.
Air Core --- Cables that are not gel filled.
Air-Gap Dielectric --- A coaxial design in which a monofilament of plastic holds the center conductor in place in a hollow plastic tube allowing the remainder of the dielectric to be air. Typical velocities of up to 84% can be achieved in this design.
Alloy --- A combination of two or more different polymers/metals. Usually combined to make use of different properties of each polymer/ metal.
Alpeth --- Coated Aluminum Polyethylene. Basic sheath.
Alternating Current (AC) --- Electric current that alternates or reverses polarity in a cyclical manner (e.g. 60 Hertz AC power)
AM --- Amplitude modulation.
American Wire Gauge (AWG) --- A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.
Ampacity --- Current handling capability expressed in amperes. The maximum current a conductor can carry without being heated beyond a safe limit.
Ampere --- A standard unit of current. Defined as the amount of current that flows when one volt of electromotive force (EMF) is applied across one ohm of resistance. One ampere of current is produced by one coulomb of charge passing a point in one second.
Amplitude The magnitude of a current or voltage. It can be the maximum, minimum, average, or RMS value of an alternating current (AC) signal. These four magnitudes are the same for a direct current (DC) signal.
Analog--- Representation of data by continuously variable quantities as opposed to a finite number of discrete quantities in digital.
Analog Signal An electrical signal which varies continuously, not having discrete values. Analog signals are copies or representations of other waves in nature. An analog audio signal, for instance, is a representation of the pressure waves which make up audible sound.
Anneal--- To soften and relieve strains in any solid material, such as metal or glass, by heating to just below its melting point and then slowly cooling it. Annealing generally lowers the tensile strength of the material, while improving its flex life and flexibility.
ANSI--- American National Standards Institute.
ASP --- Aluminum Steel Polyethylene. Provides mechanical and electrical protection.
ASTM --- The American Society for Testing and Materials, a standards organization which suggests test methods, definitions and practices.
Attenuation --- The decrease in magnitude of a signal as it travels through any transmitting medium, such as a cable or circuitry. Attenuation is usually expressed logarithmically as the ratio of the original and decreased signal amplitudes. It is usually expressed in decibels (dB).
Audio --- A term used to describe sounds within the range of human hearing (20 Hz to 20 kHz). Also used to describe devices which are designed to operate within this range.
Audio Frequency --- Frequencies within the range of human hearing (approximately 20 Hz to 20 kHz).
AWG --- American Wire Gage. A wire diameter specification. The smaller the AWG number, the larger the wire diameter.
AWM --- Appliance Wiring Material. A UL designation for a type of wire.
Bandwidth --- The difference between the upper and lower limits of a given band of frequencies. It is expressed in hertz. The range of frequencies that a transmitted communications signal occupies or that a receiving system can accept. For example, it takes more bandwidth to download a photograph in a second than to download a page of text. Virtual reality and three-dimensional audio/visual presentations require even more.
Bend Radius--- Radius of curvature that a flat, round, fiber optic or metallic cable can bend without any adverse effects.
Bonded---1. Adhesive application of a metallic shielding tape to the dielectric of a coaxial cable to improved electrical performance and ease of connector installation. Also refers to adhesive application of a metallic shielding taper to the jacket of a cable. 2. Steel is bonded to polyethylene with a copolymer adhesive All STALPETH and some ASP cables are bonded. Provides extra strength to jacket, primarily used in underground applications.
Bonded ASP--- Aluminum Steel Polyethylene where the steel is bonded to polyethylene for strength. Filled cables for use in ducts.
Bonding --- The method used to produce good electrical contact between metallic parts of any device. Used extensively in automobiles and aircraft to prevent static buildup. Also refers to the connectors and straps used to bond equipment.
Braid --- A group of textile or metallic filaments interwoven to form a tubular flexible structure which may be applied over one or more wires, or flattened to form a strap.
Braid Angle --- The angle between a strand of wire in a braid shield and the longitudinal axis (i.e. axis along the length of the center) of the cable it is wound around.
Breakdown Voltage --- The voltage at which the insulation between two conductors will fail and allow electricity to conduct or 'arc'.
Breakout --- The point at which a conductor or conductors are separated from a multi-conductor cable to complete circuits at various points along the main cable.
Broadband --- The technique used to multiplex multiple networks on a single cable without interfering with each other. Technologies that allow you to transmit or receive higher volumes of data at higher speeds.
Bunch Strand --- Conductors twisted together with the same lay and direction without regard to geometric pattern.
Buried --- Cables that are required to go underground.
C --- Capacitance (electrical). Celsius (temperature).
Cable --- A group of individually insulated conductors or subcomponents twisted helically.
Cable Modem --- A device that enables you to hook up your PC to a local cable TV line and receive data at much faster rates than telephone modems and ISDN lines. A strong competitor to DSL telephone service.
Cabling --- The grouping or twisting together of two or more insulated conductors or subcomponents to form a cable.
CACSP --- Coated Aluminum, Coated Steel, Polyethylene. Provides additional strength and protection.
Canadian Electrical Code (CEC) --- Canadian version of the US National Electrical Code (NEC).
Capacitance ---The ability of a dielectric material between conductors to store energy when a difference of potential exists between the conductors. The unit of measurement is the farad. Cable capacitance is usually measured in picofarads (pF).
CATV--- Abbreviation for Community Antenna Television. Cable TV.
CCTV--- Closed-circuit television.
Cellular Polyethylene --- Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium. The result is a desirable reduction of the dielectric constant compared to solid polyethylene, which decreases attenuation and increases the velocity of propagation.
Center-to-Center Distance --- Pitch. Nominal distance from center-to-center of adjacent conductors within a cable. When conductors are flat, pitch is usually measured from the reference edge of a conductor to the reference edge of the adjacent conductor.
Characteristic Impedance --- In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the point the voltage is applied. Or the impedance which makes a transmission cable seem infinitely long, when connected across the cable's output terminals.
Circuit--- A system of conducting media designed to pass an electric current.
Coaxial Cable --- A cylindrical transmission line comprised of a conductor centered inside a metallic tube or shield, separated by a dielectric material, and usually covered by an insulating jacket. Used by cable TV companies to distribute signals to homes and businesses. Also used by telephone companies in some applications and by cellular telephone, radio, and television installations.
Coil Effect --- The inductive effect exhibited by a spiral-wrapped shield, especially above audio frequencies.
Color Code --- A system of different colors or stripes used to identify components of cables such as individual conductors or groups of conductors.
Component Video --- The unencoded output of a camera, video tape recorder, etc., whereby each red, green, and blue video signal is transmitted down a separate cable (usually coax) to improve picture quality. Can also refer to a video system where the luminance and chrominance video components are kept separate.
Composite Cable --- Cable having conductors with two or more AWG sizes or more than one cable type.
Composite Video--- The encoded output of a camera, video tape recorder, etc., whereby the red, green, and blue video signals are combined with the synchronizing, blanking, and color burst signals and are transmitted simultaneously down one cable.
Concentric Stranding --- A group of uninsulated wires twisted together and containing a center core with subsequent layers spirally wrapped around the core with alternating lay directions to form a single conductor.
Conductivity --- The ability of a material to allow electrons to flow, measured by the current per unit of voltage applied. It is the reciprocal of resistivity and is measured in siemens (S) or mhos.
Conductor --- A substance, usually metal, used to transfer electrical energy from point to point.
Coverage --- How well a metal shield covers the underlying surface. Measured in percent.
CSA --- Abbreviation for Canadian Standards Association, the Canadian version of the Underwriters Laboratories.
Current Carrying Capacity --- The maximum current a conductor can carry without being heated beyond a safe limit. Ampacity.
Current Loop --- A two wire transmit/receive interface.
Cut-through Resistance --- A test to determine the ability of a material to withstand the application of blades or sharp edges without being cut.
dB --- Decibel.
DBS --- Direct Broadcast Satellite.
DC --- Direct current.
Decibel (dB) --- A decibel is one-tenth of a bel and is equal to 10 times the logarithm of the power ratio, 20 times the log of the voltage ratio, or 20 times the log of the current ratio. Decibels are also used to express acoustic power, such as the apparent level of a sound. The decibel can express an actual level only when comparing with some definite reference level that is assumed to be zero dB.
Dielectric --- An insulating (non-conducting) medium. It is the insulating material between conductors carrying a signal in a cable. In coaxial cables it is between the center conductor and the outer conductor. In twisted pair cables it is the insulation between conductors plus any surrounding air or other material.
Dielectric Breakdown --- Any change in the properties of a dielectric that causes it to become conductive. Normally a catastrophic failure of insulation because of excessive voltage.
Dielectric Constant --- Also called relative permittivity. That property of a dielectric which determines the amount of electrostatic energy that can be stored by the material when a given voltage is applied to it. Actually, the ratio of the capacitance of a capacitor using the dielectric to the capacitance of an identical capacitor using a vacuum (which has a dielectric constant of 1) as a dielectric. A number which indicates the quality of a material to resist holding an electrical charge when placed between two conductors.
Dielectric Heating --- The heating of an insulating material when placed in a radio-frequency field, caused by internal losses during the rapid polarization reversal of molecules in the material.
Dielectric Loss ---The power dissipated in a dielectric as the result of the friction produced by molecular motion when an alternating electric field is applied.
Dielectric Strength --- The voltage insulation can withstand before it breaks down. Usually expressed as "volts per mil".
Dielectric Withstand Voltage --- The voltage insulation can withstand before it breaks down. Usually expressed as "volts per mil".
Digital Signal --- An electrical signal which possesses two distinct states (on/off, positive/negative).
Distribution Cables --- In a CATV system, the transmission cable between the distribution amplifier and the drop cable.
Disturbed Conductor --- A conductor that receives energy generated by the field of another conductor or an external source. e.g. the quiet line.
Drain Wire --- A non-insulated wire in contact with parts of a cable, usually the shield, and used in the termination to that shield and as a ground connection.
Drop Cable --- In a CATV system, the transmission cable from the distribution cable to a dwelling.
DSL Digital --- Subscriber Line. A technology for bringing high-bandwidth information to homes and small businesses over ordinary copper telephone lines. A DSL line can carry both data and voice signals, with the data part of the line remaining continuously connected. Currently competes with the cable modem in bringing broadband services to homes and small businesses.
Duobond II --- Belden trademark for a laminated shielding tape consisting of heat sensitive adhesive, aluminum foil, polyester or polypropylene, and aluminum foil.
Duofoil --- Belden trademark for a shield in which metallic foil is applied to both sides of a supporting plastic film.
DVB --- Digital Video Broadcasting.
Elongation --- The increase in length of a wire or cable cause by longitudinal tension.
Equilay --- More than one layer of helically laid wires with the length of the lay the same for each layer.
ETP --- Abbreviation for a copper refining process called Electrolytic Tough Pitch. This process produces a conductor that is 99.95% pure copper (per ASTM B115) resulting in high conductivity.
eV --- Electron volt.
Expanded Polyethylene Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium, resulting in a desirable reduction of the dielectric constant.
Extruded Cable --- Conductors are simultaneously insulated and the cable is formed by a continuous extrusion process.
F --- Frequency.
Feeder Cable --- In a CATV system, the transmission cable from the head end (signal pickup) to the trunk amplifier. Also called a trunk cable.
FEP--- Fluorinated ethylene-propylene. A thermo-plastic material with good electrical insulating properties and chemical and heat resistance.
Fiber --- A single, separate optical transmission element characterized by core and cladding.
Fiber Optics --- Light transmission through optical fibers for communication and signaling. A technology that transmits information as light pulses along a glass or plastic fiber. Optical fiber carries much more information than conventional copper wire and is generally not subject to interference. Most telephone company long-distance lines are optical fiber. See RUS 1755.900.
Field --- An area through which electric and/or magnetic lines of force pass.
Filled --- Cables that are gel filled.
Fillers --- No conducting components cabled with the insulated conductors or optical fibers to impart roundness, flexibility, tensile strength, or a combination of all three, to the cable.
Flame Resistance---The ability of a material not to fuel a flame once the source of heat is removed.
Flat Cable --- Also referred to as planar and/or ribbon cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.
Flat Conductor --- A conductor with a width-to-thickness ratio of arbitrarily 5 to 1 or greater.
Flat Conductor Cable --- A flat cable with a plurality of flat conductors.
Flex Life--- The qualification of the number of times a cable may bend before breaking.
Flexibility --- The ability of a cable to bend in a short radius. The ability of a cable to lay flat or conform to a surface as with microphone cables.
Floating --- Referring to a circuit which has no connection to ground.
FM --- Frequency modulation.
Foam Polyethylene --- Expanded or "foam" polyethylene, consists of individual closed cells of inert gas suspended in a polyethylene medium, resulting in a desirable reduction of the dielectric constant.
FR-TPE --- FR-TPE, flame retarded thermoplastic elastomer, is a rubber-like plastic that has properties similar to rubber yet is processed as a thermoplastic. It is used as the insulation and jacket in an all TPE construction which meets UL 13 and 1277 industrial cable requirements. It has good electrical properties, abrasion resistance, colorability and flame retardancy. This compound is ideal for cold weather applications.
FREP--- Flame retardant ethylene propylene is a special flame retardant version of EPDM rubber. It is designed for use as an industrial control insulation and has excellent electrical characteristics, deformation resistance, and also meets the flame retardant needs of industrial control cables.
Frequency --- The number of times a periodic action occurs in one second. Measured in Hertz.
Frequency Response --- The amplitude versus frequency characteristics of a device. Also may refer to the range of frequencies over which the device operates within prescribed performance
Gage --- The physical diameter of a wire. A standard for expressing wire diameter. As the AWG number gets smaller, the wire diameter gets larger.
H --- Symbolic designation for magnetic field intensity. Abbreviation for henrys (unit of inductance).
Halar --- Thermoplastic fluoropolymer material with excellent chemical resistance, electrical properties, thermal characteristics, and impact resistance.
Haloarrest I --- Haloarrest I is a non-halogenated flame retarded thermoplastic polyolefin with excellent low smoke and flame properties. It is used as a jacket over the XLPE insulated singles (non-XHHW), and the entire construction meets the UL 13 and 1277 specifications as a non-halogenated PLTC/TC cable. Haloarrest I meets the European Specifications on acid gas evolution and % Halogen content. This jacket can also be used with XHHW conductors for wet ratings.
Harness --- A flat cable or group of cables, usually with many breakouts with the wire ends prepared for termination or terminated to connectors and ready to install.
HDSL --- High bit-rate Digital Subscriber Line.
HF--- High Frequency. International Telecommunication Union designation for the 3-30 MHz band of frequencies.
HFC --- Hybrid Fiber/Coaxial.
High Frequency --- International Telecommunication Union designation for the 3-30 MHz band of frequencies.
Hook-Up Wire --- Single conductor wire with various types of insulation.
I --- Symbol used to designate current.
I/O --- Interconnection Input/Output interface to the "outside world."
I2R --- Formula for power in watts, where I=current in amperes, R=resistance in ohms.
ICEA --- Insulated Cable Engineers Association.
IEEE --- Institute of Electrical and Electronic Engineers.
IF ---Intermediate Frequency.
Impedance ---The total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequency.
Impedance Match--- A condition whereby the impedance of a particular circuit cable or component is the same as the impedance of the circuit, cable, or device to which it is connected.
Impedance, Characteristic ---In a transmission cable of infinite length, the ratio of the applied voltage to the resultant current at the point the voltage is applied. Or the impedance which makes a transmission cable seem infinitely long, when connected across the cable's output terminals.
Impedance, High --- Generally, the area of 25,000 ohms or higher.
Impedance, Low --- Generally, the area of 1 through 600 ohms.
Insertion Loss --- A measure of the attenuation of a cable and/or component(s) by determining the output of a system before and after the device is inserted into the system.
Insulation --- A material having good dielectric properties which is used to separate close electrical components, such as cable conductors and circuit components.
Insulation Displacement Connector (IDC) --- A mass termination connector for flat cable with contacts that displace the conductor insulation to complete termination.
Insulation Stress ---The molecule separation pressure caused by a potential difference across an insulator. The practical stress on insulation is expressed in volts per mil.
Interface The region where two systems or a major and a minor system meet and interact with each other.
Interference --- Disturbances of an electrical or electromagnetic nature that introduce undesirable responses into other electronic equipment.
Intermediate Frequency --- A frequency to which a signal is converted for ease of handling. Receives its name from the fact that it is an intermediate step between the initial and final conversion or detection stages.
IR --- Insulation Resistance.
ISO --- International Standards Organization.
Isolation --- The ability of a circuit or component to reject interference, usually expressed in dB.
ISP ---Internet Service Provider.
ITFS --- Instructional Television Fixed Service.
ITU ---International Telecommunications Union.
Jacket --- Pertaining to wire and cable, the outer protective covering that may also provide additional insulation.
Jumper--- A short length of conductor or flat cable used to make a connection between terminals or around a break in a circuit, or between circuit boards.
keV---1000 electron volts.
Kilo--- One thousand.
kV --- Kilovolt (1000 volts).
kVA --- Kilo Volt-ampere. One thousand volt-amperes (VA). See also VA.
kW --- Kilowatt.
L--- Symbol for inductance.
Laminated Cable --- Insulated or uninsulated wires which are encapsulated by two sheets of laminate material to maintain a predetermined pitch.
LAN ---Local Area Network. A data network connecting any number of users, intended to serve a small area. A group of computers and associated devices that share a common communications line and typically share the resources of a single processor or server within a small geographic area.
Laser --- A coherent source of light with a narrow beam and a narrow spectral bandwidth (about 2nm).
Lay --- The length measured along the axis of a wire or cable required for a single strand (in stranded wire) or conductor (in cable) to make one complete turn about the axis of the conductor or cable. In a twisted pair cable, the lay length is the distance it takes for the two wires to completely twist around each other.
Leakage ---The undesirable passage of current over the surface of or through an insulator.
LEC --- Local Exchange Carrier.
LF--- Low frequency. International Telecommunication Union designation for the 30-300 kHz band of frequencies.
Loss --- Energy or signal lost without accomplishing useful work.
Lossy --- Having high losses resulting in efficiency.
Low Frequency --- International Telecommunication Union designation for the 30-300 kHz band of frequencies.
Luminance Signal --- The portion of the composite video signal that represents the brightness or the black and white information.
M ---Prefix for milli or one-thousandth.
M ---Mutual inductance. The abbreviation for mega or 1 million. And also indicates 1000 (one thousand) feet in the wire industry. Lower case m is for milli or one-thousandth. See also m.
M' ---Notation representing 1000 feet.
mA ---milliampere (one-thousandth of an ampere).
MAC --- Media Access Control (layer of OSI Reference Model).
MAN ---Metropolitan Area Network. A data network intended to serve the area of a city or an area of similar size.
Margin --- Distance between reference edge of cable and nearest edge of first conductor or center of first conductor.
Matte Finish PVC --- A special formulation of PVC which very closely looks and feels like rubber.
MATV --- Abbreviation for Master Antenna Television.
Modem --- Modulator-Demodulator. Device that converts signals in one form to another form compatible with another kind of equipment.
Molded Cable --- Cable assemblies with molded connectors on one or both ends.
Multi-Conductor Cable --- Cable with more than one conductor.
Mutual Capacitance --- Effective capacitance between two conductors when the effects of the other conductors and shield, if present, are removed.
mV ---Millivolt (one-thousandth of a volt).
mW ---Milliwatt (one-thousandth of a watt).
Mylar --- DuPont trademark for polyethylene terephtalate (polyester) film.
National Electrical Code (NEC) --- A publication of the National Fire Protection Association (NFPA) which outlines requirements for electrical wiring and building construction.
NEC --- National Electrical Code. A publication of the National Fire Protection Association (NFPA) which outlines requirements for electrical wiring and building construction.
NEMA --- National Electrical Manufacturers Association.
Neoprene A synthetic rubber with good resistance to oil, chemical, and flame. Also called polychloroprene.
Network --- A network is a method of data communications between computers.
NEXT--- Near-end Crosstalk. Crosstalk induced on the pairs, measured at the end "near" the transmitter. Usually expressed in decibels.
Nibble --- One half byte (4 bits).
Noise --- In a cable or circuit, any extraneous signal which tends to interfere with the signal normally present in or passing through the system.
Non-Paired Cable --- Cable with two or more cabled conductors that are not in a paired configuration.
Non-Plenum --- A description for a cable that does not meet the requirements of UL 910 CMP flame test. Such a cable cannot be
Numerical Aperture (NA) A measure of the angular acceptance for a fiber. It is approximately the sine of the half-angle of the acceptance cone.
Nylon --- An abrasion-resistant thermoplastic with good chemical resistance.
OFHC---- Abbreviation for oxygen-free, high conductivity copper. It has 99.95% minimum copper content and an average annealed conductivity of 101% compared to standard copper.
Ohm ---The unit of electrical resistance. The value of resistance through which a potential difference of one volt will maintain a current of one ampere.
Ohm's Law ---Stated E=IR, I=E/R or R=E/I. The current I in a circuit is directly proportional to the voltage E, and inversely proportional to the resistance R.
Optical Waveguide Fiber A transparent filament of high refractive index core and low refractive index cladding that transmits light.
OSI Open System Interconnect (Model for networking protocols).
OSS Operations Support Systems.
Output ---The useful power or signal delivered by a circuit or device.
Ozone--- Extremely reactive form of oxygen, normally occurring around electrical discharges and present in the atmosphere in small but active quantities. In sufficient concentrations is can break down certain rubber insulations under tension (such as a bent cable).
Paired Cable --- Cable with conductors cabled in groups of two.
PAL Phase Alternation Line. PAL is a European color TV system featuring 625 lines per frame, 25 frames and 50 fields per second. Used mainly in Europe, China, Malaysia, Australia, New Zealand, the Middle East, and parts of Africa. PAL-M is a Brazilian color TV system with 525 lines per frame, 30 frames and 60 fields per second.
Parallel Circuit --- A circuit in which the identical voltage is presented to all components, with current dividing among the components according to the resistances or the impedances of the components.
Parallel Digital --- Digital information that is transmitted in parallel form. The digits are sent on separate conductors rather than sequentially on one transmission line (serial). Often used informally to refer to parallel digital television signals.
Patchcord --- A flexible piece of cable terminated at both ends with plugs. Used for interconnecting circuits on a patchboard, in a wiring closet, or at the work area.
Peak ---The maximum instantaneous value of a varying current or voltage.
PIC --- Plastic Insulated Conductor. Provides strong insulation.
Pickup --- Any device which is capable of transforming a measurable quantity of intelligence (such as sound) into relative electrical signals (e.g., a microphone).
Planar Cable --- Also referred to as flat and/or ribbon cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.
Plastic --- High polymeric substances, including both natural and synthetic products that are capable of flowing under heat and pressure, called thermoplastics. Unlike rubber and other thermoset compounds, plastics can be remelted and reused.
Plenum --- A compartment or chamber to which one or more air ducts are connected and that forms part of the air distribution system. A description for a cable that passes the UL 910 CMP flame test requirements.
Plug A male housing with male or female contacts.
Point-to-Point Wiring ---Wiring that consists of continuous conductors terminated at each end to circuit destination.
Polarization --- The orientation of a flat cable or a rectangular connector. e.g., for gray flat cable, the colored edge indicating the number one conductor.
Polybutadiene --- A type of synthetic rubber often blended with other synthetic rubbers to improve their properties.
Polyethylene --- A thermoplastic material having excellent electrical properties. Low dielectric constant, a stable dielectric constant over all frequencies, very high insulation resistance. In terms of flexibility, polyethylene can be rated stiff to very hard, depending on molecular weight and density - low density being the most flexible and the high-density, high-molecular weight formulation being very hard. Moisture resistance is rated excellent.
Polymer --- A substance made of many repeating chemical units or molecules. The term polymer is often used in place of plastic, rubber, or elastomer.
Polyolefin --- Any of the polymers and copolymers of the ethylene family of hydrocarbons, such as polyethylene and polypropylene.
Polypropylene --- A thermoplastic similar to polyethylene but stiffer and having a higher softening point (temperature). This material is primarily used as an insulation material. Typically, it is harder than polyethylene. This makes it suitable for thin wall insulations. The dielectric constant is 2.25 for solid and 1.55 for cellular designs.
Polyurethane (PUR) --- Broad class of polymers noted for good abrasion and solvent resistance. Can be in solid or cellular form. This thermoplastic material is used primarily as a cable jacket material. It has excellent oxidation, oil, and ozone resistance. Some formulations also have good flame resistance. It is a hard material with excellent abrasion resistance. It has outstanding "memory" properties, making it an ideal jacket material for retractile cords.
Polyvinyl chloride --- A general purpose thermoplastic used for wire and cable insulation and jackets.
Portable Cordage ---Cable with two or more twisted conductors for flexible applications. Also called flexible cord.
Power Ratio ---The ratio of power appearing at the load to the input power.
PP --- Polypropylene.
PPP ---Point-to-Point Protocol.
Precision Video --- Video coaxial cables having very tight electrical tolerances in impedance, velocity of propagation, attenuation and structural return loss. Used in high quality applications such as live broadcast in network studios and pre- or post-production facilities.
Premise Cabling --- Refers to the entire cabling system used for voice, data, video and power on a user's premise. For Local Area Networks, the cabling of choice includes unshielded twisted pairs (UTP), fiber optic and coaxial cables. Of these, the UTP market is the largest, with greatest demand for cables with four pairs that meet certain standards of performance, such as Category 5 and Category 5e.
Propagation Delay--- Time required for a signal to pass from the input to the output of a device.
Pulse --- A current or voltage which changes abruptly from one value to another and back to the original value in a finite length of time. Used to describe one particular variation in a series of wave motions.
Putup --- Packaging of finished wire or cable.
PVC--- Polyvinyl chloride (see also).
Quad --- A four conductor cable. Also called "star quad".
R --- Symbol for resistance.
Radio Frequency (RF) --- Radio Frequency. Includes frequencies from a few kilohertz to several hundred gigahertz. Used to transmit information from point to point over the airwaves or down coaxial cable.
Rated Temperature --- The maximum temperature at which an electric component can operate for extended periods without loss of its basic properties.
Rated Voltage --- The maximum voltage at which an electric component can operate for extended periods without undue degradation or safety hazard.
Reactance --- A measure of the combined effects of capacitance and inductance on an alternating current. The amount of such opposition varies with the frequency of the current. The reactance of a capacitor decreases with an increase in frequency; the opposite occurs with an inductance.
Receiver --- An electronic package that converts light energy to electrical energy in a fiber optic system. Also refers to a unit that converts an RF signal to another type of signal (e.g. radio, television). See also Photodetector.
Receptacle --- A female housing with male or female contacts.
Reference Edge --- Edge of cable or conductor from which measurements are made, such as in flat cable. Sometimes indicated by a thread, identification stripe, or printing. Conductors are usually identified by their sequential position from the reference edge, with number one conductor closest to this edge.
Reflection --- The change in direction (or return) of waves striking a surface. For example, electromagnetic energy reflections can occur at an impedance mismatch in a transmission line, causing standing waves.
Reflection Loss --- The part of a signal which is lost due to reflection of power at a line discontinuity.
Repeater A receiver and transmitter combination used to regenerate an attenuated signal.
Resistance --- In dc circuits, the opposition a material offers to current flow, measured in ohms. In ac circuits, resistance is the real component of impedance, and may be higher than the value measured at dc.
Resonance --- An ac circuit condition in which inductive and capacitive reactances interact to cause a minimum or maximum circuit impedance.
Retractile Cord --- A cord having specially treated insulation or jacket so that it will retract like a spring. Retractibility may be added to all or part of a cord's length.
Return Loss --- Measure of signal reflections from a cable or device with a fixed, standard reference impedance on the measuring equipment. Expressed in decibels.
RF ---Radio Frequency.
RFI--- Radio Frequency Interference.
RFP --- Request for Proposals.
RG/U --- RG is the abbreviation for radio guide, a military designation for a coaxial cable, and U stands for universal.
RGB Abbreviation for the three parts of color video signal: red, green and blue. Also refers to multi-coaxial cables carrying these signals.
Ribbon Cable ---A flat cable made with parallel round conductors in the same plane. Also referred to as planar and/or flat cable. Any cable with two or more parallel conductors in the same plane encapsulated by insulating material.
RJ-45 --- Modular telecommunications connector.
RL --- Return Loss.
Rope Strand A conductor composed of groups of twisted strands.
Round Conductor Flat Cable (RCFC) --- A cable made with parallel round conductors in the same plane.
Routing The path followed by a cable or conductor.
RSVP--- esource Reservation Protocol.
RTP --- Real-Time Transport Protocol.
Rubber (Wire Insulation) --- A general term used to describe wire insulations made of thermosetting elastomers, such as natural or synthetic rubbers, neoprene, Hypalon, butyl rubber, and others.
SAE --- Society of Automotive Engineers.
ScTP --- Screened Twisted Pair. Premise network cable with an overall foil shield.
Self-extinguishing --- The characteristic of a material that extinguishes its own flame after the igniting flame is removed.
Self-Support ---Undulated core with aluminum, polyethylene and a support strand. For aerial use.
Semi-Solid Dielectric --- A coaxial design in which a monofilament of plastic holds the center conductor in place in a hollow plastic tube allowing the remainder of the dielectric to be air. Typical velocities of up to 84% can be achieved in this design.
Semi-conductor --- In wire industry terminology, a material possessing electrical conductivity that falls somewhere between that of conductors and insulators. Usually made by adding carbon particles to an insulator. Not the same as semiconductor materials such as silicon, germanium, etc. Used for making transistors and diodes.
Sheath --- Pertaining to wire and cable, the outer protective covering, also called jacket, that may also provide additional insulation.
Shield --- A tape, serve or braid (usually copper, aluminum, or other conductive material) placed around or between electric circuits or cables or their components, to prevent signal leakage or interference.
Shield Coverage --- The optical percentage of a cable actually covered by shielding material.
Shield Effectiveness --- The relative ability of a shield to screen out undesirable interference or prevent signal leakage out of the cable. Frequently confused with the term shield coverage.
Shield Percentage --- The percentage of physical area of a circuit or cable actually covered by shielding material.
Shielded Armored--- Types of Shield: Aluminum, Aluminum/Steel, Gopher, and Copper. Cables that require some sort of shield.
Signal--- Any visible or audible indication which can convey information. Also, the information conveyed through a communication system.
Signal Conductor--- A conductor in a transmission cable or line that carries electrical signals.
Silicone --- General Electric trademark for 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. This is a very soft thermoset insulation. It has excellent electrical properties plus ozone resistance, low moisture absorption, weather resistance, and radiation resistance. It typically has low mechanical strength and poor scuff resistance.
Single Mode Fiber --- A fiber wave guide in which only one mode will propagate. The fiber has a very small core diameter of approximately 8 micro meters. It permits signal transmission at extremely high bandwidths and is generally used with laser diodes.
Single-ended--- Unbalanced, such as grounding one side of a circuit or transmission line.
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.
Skin Effect --- The tendency of alternating current to travel only on the surface of a conductor as its frequency increases.
Snake Cable--- A name given to individually shielded or individually shielded and jacketed, multi-pair audio cables. Used in the connection of multi-channel line level audio equipment.
Spacing --- The distance between the centers of two adjacent conductors. Pitch.
Span --- The distance between the center of the first conductor and the center of the last conductor in a flat cable.
Speed of Light ( c ) --- Approximately 2.998 x 10^8 meters per second.
Splitter --- A device that send the signal from one source to two or more receiving devices by allocating a portion of the signal to each receiver (e.g. cable TV splitter). A device that divides a high bandwidth signal into two or more lower bandwidth signals, each carrying a selected frequency range. Users connected to a DSL line, for example, may have a splitter installed at their home or business to divide the incoming signal into low frequencies to send to their phone and high frequencies for data to the computer.
SRL --- Structural Return Loss.
Standing Wave Ratio (SWR) A ratio of the maximum amplitude to the minimum amplitude of a standing wave stated in current or voltage amplitudes. See also Standing Wave.
Stay Cord--- A component of a cable, usually of high tensile strength, used to anchor the cable ends at their points of termination and keep any pull on the cable from being transferred to the electrical conductors.
Step --- Insulated Process of applying insulation in two layers. Typically used in shielded networking cables such that the outer layer of insulation can be removed and remaining conductor and insulation can be terminated in a RJ-45 type connector.
STP Shielded Twisted Pair(s).
Strand --- A single uninsulated wire.
Stranded Conductor --- A conductor composed of groups of uninsulated wires.
Strip --- To remove insulation from a cable or wire.
Stripping Groove --- The controlled thinning of the lamination between two conductors in a flat cable to allow easy hand separation. Tear feature.
Structural Return Loss --- Magnitude of the internal cable reflections, measured in decibels, relative to the actual cable impedance, not the system impedance. Measure of signal reflections caused by the structure of the cable without the additional reflections from any impedance mismatch between the cable and the measuring equipment. Measure of internal cable reflections using a reference impedance in the measuring equipment that is adjusted to the nominal or average impedance of the cable. See also Return Loss
Sweep Test --- Testing a characteristic of a cable or device across a range of frequencies. In cable, it usually implies return loss or structural return loss (see also).
TCP/IP--- Transmission Control Protocol/Internet Protocol.
Tear Feature --- The controlled thinning of the lamination between two conductors in a flat cable to allow easy hand separation.
Teflon (R) --- DuPont Company trademark for fluorocarbon resins. (FEP - Fluorinated ethylene-propylene. A thermo-plastic material with good electrical insulating properties and chemical and heat resistance.). (TFE - Tetrafluoroethylene. A thermoplastic material with good electrical insulating properties and chemical and heat resistance.). It is not suitable where subjected to nuclear radiation and does not have good high voltage characteristics. FEP Teflon is extrudable in a manner similar to PVC and polyethylene. This means that long wire and cable lengths are available. TFE Teflon is extrudable in a hydraulic ram type process. Lengths are limited due to amount of material in the ram, thickness of the insulation, and preform size. TFE must be extruded over a silver- or nickel-coated wire. The cost of Teflon is approximately 8 to 10 times more per pound than PVC compounds.
Tefzel --- Fluorocopolymer thermoplastic material has excellent electrical properties, heat resistance, chemical resistance, toughness, radiation resistance, and flame resistance.
Temperature Rating--- The maximum temperature at which the insulating material or cable may be used in continuous operation without change of its basic properties.
Tensile Strength --- The pull stress required to break a bare wire.
TFE--- Tetrafluoroethylene. A thermoplastic material with good electrical insulating properties and chemical and heat resistance.
Thermal Rating --- The temperature range in which a material will perform its function without undue degradation.
Thermoplastic --- A material which will soften, flow, or distort appreciably when subjected to sufficient heat and pressure. Examples are polyvinyl chloride and polyethylene.
Thermosetting --- A material which will not soften, flow, or distort appreciably when subjected to heat and pressure. Vulcanizable. Examples are rubber and neoprene.
TIA--- Telecommunications Industry Association. Body which authored the TIA/EIA 568A"Commercial Building Telecommunications Wiring Standard" in conjunction with EIA.
TP-PMD Twisted Pair-Physical Medium Dependent.
Transmission Line --- An arrangement of two or more conductors, a coaxial cable, or a waveguide used to transfer signal energy from one location to another.
Transmission Line Cable --- Two or more conductors placed within a dielectric material in such a way as to control the electrical characteristics.
Transmitter --- The electronic package that converts electrical energy to light energy in a fiber optic system. Also refers to equipment that generates RF or electrical signals for transmission through the air or space or over a transmissions line.
Triad Cable --- Cable with three twisted conductors.
Triaxial Cable --- A cable construction having a conductor, and two isolated braid shields, all insulated from each other. A coaxial cable with a second braid applied over an inner jacket and an outer jacket applied over the outer braid. Commonly used in television camera systems.
Trunk Cable --- In a CATV system, the transmission cable from the head end (signal pickup) to the trunk amplifier. Also called a feeder cable.
Twin-lead --- A transmission line having two parallel conductors separated by insulating material. Line impedance is determined by the diameter and spacing of the conductors and the insulating material and is usually 300 ohms for television receiving antennas.
Twinax Cable --- Cable with two twisted conductors with established electrical properties (one pair=twinax).
Twisted Pair ---Two lengths of insulated conductors twisted together. The traditional method for connecting home and many business computers to the telephone company. Gets its name because two insulated copper wires are twisted together, both of which are needed for each connection. In commercial environments, performance of data transmission can be improved by adding a composite tape to the wire. This is known as shielded twisted pair.
Two pair premise wiring --- Refers to the two pairs of voice grade (low bandwidth) twisted pair wire installed in most homes since the 1950s. The extra pair makes it possible for you to add another line when you need it.
UHF --- Ultra High Frequency. International Telecommunication Union designation for the 300-3000 MHz band of frequencies.
UL --- Underwriters Laboratories. A nonprofit organization which tests and verifies construction and performance of electronic parts and equipment, including wire and cable.
UTP --- Unshielded Twisted Pair(s).
V--- Volt (see also).
Velocity of Propagation (VP) --- The transmission speed of electrical energy in a length of cable compared to speed of light in free space. Usually expressed as a percentage.
VHF --- Very High Frequency. International Telecommunication Union designation for the 30-300 MHz band of frequencies.
Video --- Pertaining to picture information in a television system.
VLF --- Very Low Frequency. International Telecommunications Union designation for the 3-30 kHz band of frequencies.
Volt --- A unit of electromotive force.
Voltage --- Electrical potential of electromotive force expressed in volts.
Voltage Drop --- The voltage developed across a component or conductor by the current flow through the resistance or impedance of the component or conductor.
Voltage Rating --- The highest voltage that may be continuously applied to a cable construction in conformance with standards or specifications.
W--- Symbol for watt or wattage.
Wall Thickness --- The thickness of an insulation or jacket.
WAN--- Wide Area Network.
Watt --- A unit of electrical power.
Wavelength ---The distance between positive peaks of a signal. As the frequency increases, and waves get closer together, the wavelength decreases.
WCS --- Wireless Communications Service.
Wire --- A conductor, either bare or insulated.
XLPE--- Crosslinked polyethylene is a thermoset and is crosslinked by radiation, thermally, or by moisture. XLPE offers a wide range of operating temperatures, excellent deformation, abrasion, and flame resistance. XLPE can be formulated with halogenated or non-halogenated flame retardant packages. Some grades are also rated XHHW-2 which offers excellent wet electrical properties.
XLR---A multi-pin audio connector (typically 3 pins) used in microphone, line level and snake cable audio connections.
XPE-PVC--- Expanded Polyethylene-Polyvinyl Chloride. Fire retardant.
Z--- Symbol for impedance