Cables Glossary
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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
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Adaptor
A component to permit electrical connection between two or more connectors where direct connection is not mechanically possible.
Air Spaced Cables
A cable in which air is the essential dielectric material. A spirally wound synthetic filament or spacer may be used to center the conductor.
Alternating Current (AC)
An electric current continually reversing in direction, represented by a sinusoidal waveform.
Alternating Current Resistance
electrical resistance (usually ohms/km) of a cable when measured with alternating current. (This will generally be higher than the direct current resistance, and is needed for the purpose of circuit rating calculations.)
Ambient Temperature
The temperature of any medium surrounding an object.
American Wire Gauge (AWG)
An American standard system to indicate wire diameter. The smaller the AWG number, the larger the wire diameter.
Ampacity
The maximum allowable continuous current carrying capacity of a conductor without exceeding either the insulation or jacket material limitations. (See also Current Carrying Capacity).
Ampere
The unit of current flowing through one ohm of resistance at one volt potential.
Anneal
To soften and relieve strains in any solid material 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.
Aramid Yarn
Generic name for a tough synthetic material that is often used in cable construction to provide tensile strength.
Armour
A braid or wrapping of metal, (usually steel), or non-metallic material used to protect a cable from mechanical stress. This is generally placed under the outer sheath.
Attenuation
The power loss in an electrical system. In cables, this is generally expressed as db per unit length, usually a Km.
Attenuator
An electronic device that reduces the amplitude or power of a signal without distorting its waveform. Attenuators are usually passive devices made from resistors.
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Backbone Cable
A cable used to interconnect buildings.
Balanced Cable
Cables of which the transmission lines are symmetrical pairs. (See also Symetrical Cable).
Balanced Pair
The assembly of two insulated conductors twisted together. (See also Symetrical Pair).
Balun
A device used to convert an unbalanced circuit to a balanced circuit.
Bedding
The additional underlying sheath of a cable which protects the cores from mechanical stress.
Braiding
Interwoven textile or metallic filaments forming a tubular flexible structure around a cable.
Bundle
A number of individual cable elements contained within a single jacket or sheath and distinguished from other groups in the same cable.
Buried cable
A cable installed directly into the earth without the use of a conduit.
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Cable
An insulated group of one or more conductors or optical fibres in twisted or parallel configuration with a protective sheath.
Cable Assembly
A completed cable and its associated hardware.
Cable Core
The conductor with its own insulation (and screens if any) lying under the outer protective covering(s) of a cable.
Cable Drum
A cylinder onto which cable is wound during manufacture, for storage, transportation and installation.
Capacitance
The ability of a dialectric material between conductors to store electric charge when a difference of potential exists between the conductors. The unit of measurement is the farad, which is the capacitance value that will store a charge of one coulomb when a one-volt potential difference exists between the conductors. In ac, one farad is the capacitance value which will permit one ampere of current when the voltage across the capacitor changes at the rate of one volt per second.
CATV System
Community antenna television.
Cladding
A low refractive index material that surrounds the core of an optical fibre causing the transmitted light to travel down the core and protects against surface contaminant scattering.
Coaxial Cable
A cable consisting of two conductors with a common axis separated by a dielectric.
Common-mode
The mode where the voltage of both conductors of a pair, relative to ground potential is equal and in phase.
Composite Cable
A cable containing more than one gauge size or a variety of circuit types, eg. pairs, triples, quads, coaxials, etc.
Concentric Stranding
A conductor consisting of a central wire or core surrounded by one or more layers of helically wound wires.
Conductivity
The capability of a material to carry an electrical current. Usually expressed as a percentage of copper conductivity - copper being one hundred (100%) percent.
Conductor
A material capable of carrying electric current. The most common materials for wire and cable applications are aluminium and copper.
Conductor Resistance
The ratio of the potential difference across to the current flowing through a conductor. Usually expressed in ohms/km. This parameter is required for voltage drop and current rating calculations. (See also Resistance).
Connector
A device used to physically and electrically connect two or more conductors.
Core
The central component or assembly of components over which other materials are applied, such as a shield, sheath, or armour.
Core Identification
The method of distinguishing between multiple cores, either with a colour or a number.
Crimp Termination
A wire termination that is attached by compression to the conductor.
Cross sectional area (CSA)
The area of the cut surface of the conductor of a cable cut at right angles to the length of the cable.
Crosstalk
The electrical interference between adjacent conductors.
Current Carrying Capacity
This is the maximum allowable continuous current carrying capacity of a conductor without exceeding either the insulation or jacket material limitations. (See also Ampacity)
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Dielectric
An insulating material between conductors in a cable.
Dielectric Strength
The voltage which an insulating material can withstand before breakdown occurs.
Differential-mode
The mode of transmission where the voltage is equal and in opposite phase on each conductor relative to ground potential.
Direct Burial Cable
A cable installed directly in the earth without a conduit.
Direct Current
An electrical current that flows in one direction only.
Direct Current Resistance
The resistance offered by a circuit to the flow of direct current.
Direction of Lay
The direction, clockwise or counter-clockwise, of a conductor or group of conductors when looking axially down a cable length.
Dissipation
The loss of energy, as the production of waste heat in a circuit.
Distribution Cable
The transmission cable between the distribution amplifier and the drop cable in a CATV system.
Drain Wire
An uninsulated wire usually place directly beneath an electrical contact with a grounded shield, which is used for making ground connections.
Drop Cable
The transmission cable from the distribution cable to a dwelling in a CATV system.
Duct
An tube or trough used for carrying electrical conductors and designed for mechanical protection.
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Earth Continuity Conductor
A conductor used to connect equipment (or the earth circuit of a wiring system) to a grounding electrode.
EL-FEXT (Equal Level of FEXT)
Calculation that normalises the results of Far End Cross Talk (FEXT) as it takes attenuation into account. It is calculated by subtracting attenuation of interfering pairs from the FEXT.
Electrical Length
The length of cable multiplied by the relative propagation velocity.
Electrical Screen
A metallic shield which isolates a device from external fields.
Electromagnetic Disturbance
The disturbance of a signal by a superimposed electromagnetic field.
Ethylene Propylene Diene Monomer (EPDM)
An ozone resistant rubber consisting primarily of ethylene propylene diene terpolymer.
Ethylene Propylene Rubber (EPR)
An ozone resistant rubber consisting primarily of ethylene propylene copolymer.
Extrusion
The process of applying an insulation or sheath compound over a conductor, or core by forcing material through a die.
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Fault current
The maximum electrical current that flows through a circuit during an electrical fault condition prior to the activation of a current limiting device.
Filler
The material used in multi-conductor cables to occupy large interstices formed by the assembled conductors, which imparts flexibility, strength and shape to the cable.
Fire Integrity
This refers to the amount of time a cable can be exposed to a flame and continue to function.
Fire Resistance
The ability of a cable to continue to transmit a signal for a specific period of time while in the presence of a fire.
Flame Retardance
The ability of a cable to restrict the propagation of flames in the event of a fire.
Flexible Cable
A cable or cable component which is capable of repeated bending under the influence of an outside force.
Foam Filled
The cellular structured insulation typically found in coaxial cable which acts as a dielectric.
Foil
The film of metal or composite polymer which is used as a screen in the cable construction.
Foiled Twisted Pairs Cable (FTP)
A cable containing multiple twisted pairs of wire enclosed in a foil screen. Also known as Screened Twisted Pairs.
Frequency
The number of cycles which occur in one second. Frequency is measured in Hertz.
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Graded-Index Fibre
A multimode optical fibre in which the refractive index of the core is lower toward the outside of the fibre core and increases toward the centre.
Grounding Conductor
A conductor used to connect equipment (or the earth circuit of a wiring system) to a grounding electrode.
GSWB
Galvanised Steel Wire Braid.
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Halogen
A particular group of elements with similar bonding properties, consisting of flourine, chlorine, bromine and iodine. Halogen gases are poisonous when inhaled.
Heat Endurance
The time of heat aging that a material can withstand before failing a specific physical test.
Heat Resistance
The property of a material to resist the deteriorating effects of elevated temperatures.
Helix
A spiral winding.
Hertz
The term to denote cycles-per-second as an indication of frequency.
HOFR
Heat and Oil Resistant, Flame Retardant (also Hypalon/CSP Chlorosulphated Polyethylene).
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Impedance
The total opposition that a circuit offers to the flow of a current at a particular frequency.
Inductance
The property of wire which stores electrical current in a magnetic field around the wire. This can be intensified by coiling the wire.
Insertion Loss
The loss of power that results from inserting a component, such as a connector or splice, into a previously continuous path.
Insulation
A material having high resistance to the flow of electric current. Often called a dielectric.
Insulation Resistance
That property of an insulating material which resists electrical current flow through the insulating material when a potential difference is applied.
Interference
The undesired electrical or electromagnetic signal induced into a conductor.
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Jacket
The material, usually an extruded plastic or elastomer, applied outermost to a wire or cable to provide mechanical and environmental protection. (See also Sheath).
Jumper
A short length of conductor used to make a connection between terminals or around a break in a circuit.
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Lay
The length measured along the axis of a wire or cable of one complete helix of a strand or conductor.
Loss Factor
The dissipation multiplied by the dielectric constant of an insulation material.
LSF
Low Smoke and Fume.
LSZH
Low Smoke Zero Halogen.
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Marker Tape
A tape, imprinted with the manufacturer's name, and various other relevant information and laid parallel to the conductors in a cable under the outer sheath.
Mechanical Splice
A semi-permanent joint created by mechanical means, which ensures the electrical/optical continuity of conductors or fibres.
Messenger Wire
A longitudinal wire supporting the weight and enhancing the tensile strength of a suspended cable.
Minimum Bending Radius
The radius to which a copper or fibre cable can be bent before the risk of breakage or the degradation of performance occurs.
Moisture Absorption
The amount of moisture, in percentage, that an insulation or a jacket will absorb under specified conditions.
Multiconductor
More than one conductor within a single cable complex.
Multifibre Cable
An optical fibre cable containing two or more fibres.
Multimode Fibre
Fibre with a comparatively wide optical core, permitting several light modes to pass at once.
Mutual Capacitance
Capacitance between two conductors when all other conductors are connected together.
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NBR
Nitrile Butadiene Rubber. Good oil and chemical resistance.
Neoprene
A polychloroprene synthetic rubber with excellent flame retarding and abrasion resisting qualities used as a jacketing material. (Also see Polychloroprene).
Neutral Conductor
The wire in a two-wire AC electrical system that carries the return current.
Nominal Thickness
The specified, indicated, or named thickness of an extruded layer in a wire or cable.
Numerical Aperture
The "light gathering ability" of a fibre, defining the maximum angle to the fibre axis at which light will be accepted and propagated through the fibre.
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Ohm
The unit of electrical resistance. It is the value of resistance through which a potential difference of one volt will maintain a current of one ampere.
Ohm's Law
Stated V=IR, I=V/R or R=V/I, the current I in a circuit is directly proportional to the voltage V, and inversely proportional to the resistance R.
Operating Temperature
The range of temperatures between which cables will continue to function acceptably.
Optical Fibre
Translucent fibre which can transmit beams of laser light.
Optical Fibre Cable
A cable in which the transmission elements are optical fibres.
Outer Protection
The outer layer of a cable intended to enhance the mechanical protection from external factors.
Outside Diameter
The length of a straight line passing through the center of a cable and connecting two points on the circumference.
Ovality
Distortion of pipe or round tube from its normal, round shape to an oval shape.
Overhead (Aerial) Cable
A cable suspended in the air on poles or other overhead structures
Oxygen Index (OI)
Percentage of Oxygen required to support combustion.
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Partial Discharge Test
A test to measure the electrical discharge or spark that bridges a portion of the insulation between two conducting electrodes. Partial discharge can occur at any location within the insulation system (between the two electrodes) where the electric field strength exceeds the breakdown strength of that portion of the insulating material.
Pigtail
A short length of optical fibre or cable that has a connector installed on one end.
Plug
A connector used for attachment on the free end of a cable.
Polychloroprene (PCP)
A synthetic rubber with excellent flame retarding and abrasion resisting qualities used as a jacketing material. (Also see Neoprene).
Polyethylene
A thermoplastic material composed of polymers of ethylene. It has excellent dielectric properties.
Polyvinyl Chloride (PVC)
A family of vinyl compounds widely used as insulation on low voltage applications and jacketing for many types of cables.
Power Rating
The maximum continuous input power when the cable is terminated with its nominal impedance.
Primary coating
The plastic coating applied directly to the cladding surface during manufacture of optical fibres to preserve the integrity of the surface.
Propagation Time
Time required for a wave to travel between two points on a transmission line.
PS-ELFEXT (Power Sum Equal Level FEXT)
Sum of EL-FEXT, which is the calculation that normalises the results of Far End Cross Talk (FEXT) as it takes attenuation into account. It is calculated by subtracting attenuation of interfering pairs from the FEXT.
PS-NEXT (Power Sum NEXT)
Algebraic sum of Near End Cross Talk (NEXT). Three pairs as they affect one pair.
PSACR
Power Sum Attenuation to Cross Talk Ratio
Pull Strength
The pulling force that can be safely applied to a cable without damage.
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Quad
A term used to describe a cable consisting of four separately insulated conductors twisted together.
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Reflected Wave
A wave that travels from the discontinuity in a transmission line in an opposite direction to that of the incident wave.
Refraction
The bending of light as it passes from one medium to another.
Resistance
The ratio of the potential difference across to the current flowing through a conductor. Usually expressed in ohms/km. This parameter is required for voltage drop and current rating calculations.(See also Conductor Resistance).
Resistor
A two-terminal electrical or electronic component that resists an electrical current by producing a voltage drop between its terminals in accordance with Ohm's Law.
Return Loss
The ratio, at the junction of a transmission line and a terminating impedance or other discontinuity, of the amplitude of the reflected wave to the amplitude of the incident wave. The return loss value describes the reduction in the amplitude of the reflected energy, as compared to the forward energy.
Riser Cable
Indoor cables made especially for between floor applications.
RL-DB
Return Loss. The ratio, at the junction of a transmission line and a terminating impedance or other discontinuity, of the amplitude of the reflected wave to the amplitude of the incident wave. The return loss value describes the reduction in the amplitude of the reflected energy, as compared to the forward energy.
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Screen
The conducting layer of a cable which has the function of controlling the electric field within the cable core or element.
Screened Twisted Pairs Cable (STP)
A cable in which each twisted pair is individually screened. It may also have an additional overall screen.
Screening Effectiveness
The measure of the ratio of the power inside the cable to the total radiated power outside.
Secondary Coating
A coating applied directly to the primary coating of one or more fibres to reinforce the protection of the optical fibre during handling and cabling. Also known as a buffer.
Secondary Insulation
Any extremely high resistance material which is placed over primary insulation to protect it from abrasion.
Semi Rigid Cable
A cable containing a flexible inner core and a relatively inflexible sheathing material, such as a metallic tube.
Semi-Conductor
A material possessing electrical conductivity that falls somewhere between that of conductors and insulators.
Semi-Flexible Cable
A cable not intended for applications requiring repeated flexing of the cable in service but bending or forming is permissible during installation.
Sheath
The material, usually an extruded plastic or elastomer, applied outermost to a wire or cable to provide mechanical and environmental protection.(See also Jacket).
Shield
A metallic layer of tape, braid or spiral wrapped wire construction (commonly aluminium or copper) with the primary purpose of preventing electrostatic or electromagnetic interference between adjacent wires and external sources.
Shield Coverage Percentage
Percentage of the surface are of a cable core surface area which is covered by the shield.
Single Mode Fibre
A fibre with a small core, usually between 2 and 9 microns that can only support one wavelength.
Socket/Jack
A connector for attachment to the fixed end of a cable.
Solid Dielectric Cables
Cables in which the space between the inner conductor and outer conductor is substantially filled by solid plastic dielectric.
Spark Test
A test designed to locate flaws in an insulated wire by application of an electrical potential across the material for a very short period of time while the wire is drawn through an electrode field.
Spike Test
A Spike Test is a test specifically designed to prove that the screen of a cable can withstand a full specified fault current for a defined period. It simulates the accidental “spiking” of a live cable installation and ensures that the circuit protection will operate and the circuit fails to safety.
Splice
A connection of two or more conductors or cables to provide good mechanical strength as well as good conductivity.
Standards
An agreed set of guidelines used to maintain the level of quality in the production of cables and their component elements.
Static Bending Radius
The smallest radius to which an installed cable can be bent once without impairing its transmission characteristics.
Strand
A single uninsulated wire.
Stranded Conductor
A conductor composed of individual wires twisted together.
Strength Member
An element which mechanically reinforces a cable, in particular against tension, compression or bending.
SWA
Steel Wire Armour.
Symmetrical Cable
Cables of which the transmission lines are symmetrical pairs. (See also Balanced Cable).
Symmetrical Pair
The assembly of two insulated conductors twisted together. (See also Balanced Pair).
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TCWB
Tinned Copper Wire Braid.
Temperature Rating
The maximum temperature at which the insulating material may be used in continuous operation without loss of its basic properties.
Thermoplastic Insulation
A material which will soften, flow or distort when subjected to heat and pressure. Examples are PVC (Polyvinyl Chloride) and PE (Polyethylene).
Thermoset Insulation
A material which will not soften, flow or distort when subjected to heat and pressure, eg. XLPE (cross-linked Polyethylene) and Neoprene.
Tight Bufferred Cable
A cable construction where each fibre is tightly buffered by a protective thermoplastic coating.
Tinned Wire
Copper wire coated with tin to make soldering easier and to inhibit corrosion.
TPE
Thermoplastic Elastomer.
Transfer Impedance
The ratio of the induced voltage inside the cable to the inductive current outside the cable.
Transmission Line
A way of conveying electromagnetic energy between two points with a minimum of radiation.
Trefoil
A cross-sectional arrangement of cables that minimises electrodynamic forces during fault conditions.
Twisted Pair
A cable composed of two insulated conductors, twisted together without a common covering.
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Underground Cable
A cable installed in an underground trough or duct system which separates the cable from direct contact with the soil.
Uscreened Twisted Pair Cable (UTP)
Unshielded twisted pair is the most common kind of copper telephone wiring.Twisted pair is the ordinary copper wire that connects home and many business computers to the telephone company.
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Volt
The potential difference across a conductor when a current of one ampere dissipates one watt of power.
Voltage Drop
The voltage developed between the terminals of a circuit component by the flow of current through the resistance or impedance of that part.
Voltage Rating
The highest voltage that may be continuously applied to a wire or cord in conformance with standards or specifications.
Voltage Withstand Test
A test used to stress the insulation of a product far beyond what it would it encounter during normal operation.
VoP
Velocity of Propagation. The speed at which an electrical signal passes through a medium. Expressed as a percentage, it is the ratio of a signal's transmission speed compared to the speed of light in a vacuum.
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Wave Length
The distance between positive peaks of a signal. As the frequency increases, and waves get closer together, the wavelength decreases.
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XLPE
Cross-linked Polyethylene.
