Cable & Wire Terminology
AAR -American Association of Railroads
Abrasion Resistance -Ability of a wire, cable or material to resist surface wear.
Accelerated Life Test -An accelerated life test is a test in which certain factors such as
voltage, temperature, etc. to which a cable is subjected are increased in magnitude
above normal operating values to obtain observable deterioration in a reasonable period
of time and thereby afford some measure of the probable cable life under operating
voltage, temperature, etc.
Accelerator -A chemical additive which hastens a chemical reaction under specific
conditions. A.C. Resistance -The total resistance offered by a device in an alternating
Activator - A chemical additive used to initiate the chemical reaction in a specific
current circuit due to inductive and capacitive effects, as well as the direct current
Active Current -In an alternating current, a component in phase with the voltage; the
working component as distinguished from the idle or wattles component.
Active Pressure -In an A.C. circuit, the pressure which produces a current, as
distinguished from the voltage impressed upon the circuit.
Admittance - The measure of the ease with which an alternating current flows in a
circuit. The reciprocal of impedance.
Adhesion -The state in which two surfaces are held together by interfacial forces which
may be chemical or mechanical in nature.
Aging - The irreversible change in properties or appearance of a material with time and
under specific conditions (usually accelerated representations of environmental states,
such as high temperature, oxygen or other carious conditions).
Alloy - A metal formed by combining two or more different metals to obtain desirable
Alternating Current (AC) -Electric current that continually reverses its direction; it is
expressed in cycles per second (hertz or Hz).
Alternating Voltage - The voltage developed across a resistance or impedance
through which alternating current is flowing.
Ambient Temperature - Any all encompassing temperature within a given area
Ampacity -The maximum current an insulated wire or cable can safely carry without
exceeding either the insulation or jacket material limitations (Same as Current Carrying
Ampere -The unit of current. One ampere is the current flowing through one ohm of
resistance at one volt potential
Ampere's Law -The magnetic intensity at any point near a current carrying conductor
can be computed on the assumption that each infinitesimal length of the conductor
produces at the point of an infinitesimal magnetic density The resulting magnetic
intensity at the point is the vector sum of the contributions of all the elements of the
Anneal - Relief of mechanical stress through heat and gradual cooling Annealing
copper renders it less brittle.
Annular Conductor -A number of wires stranded in three reversed concentric layers
around a core
Anode - The electrode through which a direct current enters the liquid gas or other
discrete part of an electrical circuit the positively charged pole of an electrochemical
ANSI -The American National Standards Institute
Anti-Oxidant - A substance which prevents or slows down oxygen decomposition
(oxidation) or a material exposed to air.
Anti Ozonant - A substance which prevents or slows down material degeneration due
to ozone reaction.
Arc - 1.) A Luminous glow formed by the flow of electric current through ionized air, gas
or vapor between separated electrodes or contacts. 2) A portion of the circumference of
Arc Over Voltage -The minimum voltage required to create an arc between electrodes
separated by gas or liquid insulation under specified conditions.
Area of conductor - The size of a conductor cross-section, measured in circular mils
square inches, etc.
Armor - A braid or wrapping of metal, usually steel, used for mechanical protection.
Generally placed over the other sheath.
ASA - The American Standards Association. Former names of ANSI.
ASME - The American Society of Mechanical Engineers.
ASP -Aluminum Steel Polyethylene. Provides mechanical and electrical protection.
ASTM - The American Society for Testing and Materials
Attenuation - Power loss in an electrical system. In cables, generally expressed on dt
per unit length, usually 1000ft.
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.
Balanced Credit -A circuit so arranged that the impressed voltages on each conductor
of the pair are equal in magnitude but opposite in polarity with respect to ground.
Balium - A device for matching an unbalanced coaxial transmission line to a balanced
Band Marking - A continuous circumferential band applied to a conductor at regular
intervals for identification.
Band Width -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
Bare Conductor -A conductor having no covering. A conductor with no coating or
cladding on the copper.
Binder -A tape or thread used for holding assembled cable components in place.
Blown jacket -Outer cable covering applied by controlled inflation of the cured jacket
tube then pilling the cable through it.
Bond -An attachment at and interface between an adhesive and an adherent or
between materials attached together.
Bond Strength -Amount of adhesion between surfaces, e.g., in bonded ribbon cable.
Booster -An amplifier inserted into a cable to increase the signal amplitude in order to
compensate for signal loss due to attenuation. This extends the transmission range of
the cable. Transformers may be employed to boost ac voltages. The term booster is
also applied to amplifiers used in television receiving antenna systems.
Boot -A protective covering over any portion of a cable or conductor in additions to its
jacket or insulations.
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.
Braid Carrier - A spool or bobbin on a braider which holds on group or strands or
filaments consisting of a specific number of ends. The carrier revolves during braiding
Brand Ends - The number of strands used to make up one carrier. The strands are
wound side by side on the carrier bobbin and lie parallel in the finished braid.
Brazing -The joining of ends of two wires, rods or groups of wires with a nonferrous
filler metal at temperature above 800F (427C).
Breakdown (Puncture) - A disruptive discharge though the insulation.
Breakdown of Insulation -Failure of an insulation resulting in a flow if current through
the insulation. It may be caused by the application of too high voltage or by defects or
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 multiconductor
cable to complete circuits at various points along the main cable.
Building Wire -ire used for light power 600 Volts or less, usually not exposed to
Bunch Stranding - Conductors twisted together with the same lay and direction without
regard to geometric pattern.
Bundle (fiber optic) - A number of fibers grouped together, usually carrying a common
Buried Cable -A cable installed directly in the earth without use of underground
conduit. Also called "direct buried cable".
Bus -Wire used to connect two terminals inside of and electrical unit.
Butt -joining of two conductors end to end, with no overlap and with the axes in line.
Butt Splice -A splice wherein two wires from the opposite ends butt against each
other, or against a stop, in the center of a splice.
Butt Wrap -Tape wrapped around an object or conductor in a edge-to-edge condition.
Byte -A group of eight adjacent binary digits (8 bits).
Cable -A group of individually insulated conductors or subcomponents twisted helically.
Cable Assembly - A completed cable and its associated hardware ready to install.
Cable Filter - The material used in multiple conductor cable to occupy the spaced
forced by the assembly of components, thus forming a core of the desired shape
Cabling -The grouping or twisting together of two or more insulated conductors or
subcomponents to form
Cabling Factor - Used in the formula for calculating the diameter of and unshielded,
unjacketed cable. D-Kd, where D is the cable diameter, K is the factor and d is the
diameter of one insulated conductor.
Caged Armor -A construction using wires within a jacket to increase mechanical
protection and tensile strength. This construction is sometimes used in submarine
Capacitance -Storage of electrically separated charges between two plates having
different potentials. The value depends largely on the surface area of the plates and the
distance between them.
Capacitance Direct -The capacitance measured directly from conductor to conductor
through a single insulating layer.
Capacitance Mutual -The capacitance between two conductors with all other
conductors including shield, sort circuited to ground.
Capacitance, Unbalanced to ground - An inequality of capacitance between the wires
of two or more pairs which result in a transfer of unwanted signal from one pair to
Capacitive Coupling - Electrical interaction between two conductors caused by the
capacitance between them.
Carrier -The basic woven grouping of a braided shield consisting of one or several
Cathode - Negative pole of an electric source
Cathodic Protection -The control of the electrolytic corrosion of an underground or
underwater metallic structure by the application of an electric current through a
sacrificial anode in such a way that the structure is made to act as a cathode of an
Cellular Polyethylene - Expanded or "foam" polyethylene consisting of individual
closed cells suspended in a polyethylene medium.
Center to Center - Distance See Pitch
Certificate of Compliance (C of C) - A certificate which shows that the product being
shipped meets customer's specifications.
Certified Test Report (CTR) - A report providing actual test data on a cable. Tests are
normally run by a Quality Control Department, which shows that the product being
shipped conforms to test specifications.
Characteristic Impedance - The impedance that, when connected to the output
terminals of a transmission line of any length, makes the line appear infinitely long. The
ratio of voltage to current at every point along a transmission line on which there are no
Charge - The quantity of electricity held statically in a condenser or on an insulated
Charging Current -The current produced when a DC voltage is first applied to
conductors of an un-terminated cable. It is caused by the capacitive reactance of the
cable, and decreases exponentially with time.
Charging Time - The time required for the voltage between two conductors of a cable
to acquire a value equal to 98.2% of the magnitude of an instantaneously applied DC
Chlorosulfonated Polyethylene (CSPE) -A rubbery polymer made by treating
polyethylene with chlorine and sulfur dioxide It is suitable compounded and cross linked
for application as jacket or as insulation Manufactured by E.I. DuPont under trade name
Circuit -The complete path through which a current flows or part of the complete path
such as one conductor.
Circuit Sizes - A popular term for building wire sizes 14 through 10 AWG.
Circular Mil -The area of a circle one mil (.001") in diameter, 7.546 x 10-7 sq. in. Used
in expressing wire cross sectional area
Cladding - A method of applying a layer of metal over another metal whereby the
junction of the two metals in continuously welded.
Coat - To cover with a continuous layer of compound (such as varnish) for purposed of
depending on the nature of the substance.
fishing, protection, or enclosing. Usually comprises variable degrees of impregnation
Coating -A material applied to the surface of a conductor to prevent environmental
deterioration, facilitate soldering or improve electrical performance.
Coaxial Cable - A cable consisting of two cylindrical conductors with a common axis,
separated by dielectric.
Cold Flow -Permanent deformation od the insulation due to mechanical force or
pressure (not due to heat softening).
Cold Test - any test to determine the performance of cables during or after subjection
to a specified low temperature for a specified time.
Color Test -a system for circuit identification through use of solid colors and
Common Axis Cabling -in multiple cable constructions, a twisting of all conductors
about a "common axis" with two conductor groups then selected as pairs. This practice
yields smaller diameter contructions that does a separate axis construction, but tends to
yield greater susceptance to EMI and ESI.
Common Mode (Noise) - caused by a difference in "ground potential". By grounding at
either end rather than both ends (usually grounded at source) on can reduce this
Compact Stranded Conductor - a unidirectional or conventional conductor
manufactured to a specific diameter, approximately 8 to 10% below the nominal
diameter of a non-compact conductor of the same cross sectional area.
Compatibility -the ability of dissimilar materials to exist in mutual proximity or contract
without changing their physical or electrical properties.
Composite Cable -a cable consisting of two or more different types or sizes of wires.
Compound - an insulating or jacketing materials made by mixing two or more
Concentric Stranding -a central wire surrounded by one or more layers of helically
wound strands in a fixed round geometric arrangement.
Concentricity - in a wore or cable, the measurement of the location of the center of the
conductor with respect to the geometric center of the surrounding insulation.
Conductance -the ability of a conductor to carry electric current. It is the reciprocal of
resistance and is measure in ohms.
Conductivity -the capability of material to carry electrical current-usually expressed as
a percentage of copper conductivity (copper being 100%)
Conductor -an un-insulated wire suitable for carrying electrical current.
Conduit -a tube or trough in which insulated wired and cable are run.
Connector - a device used to physically and electrically connect two or more
Contract - the part of a connector which actually carried the electrical current, and are
touched together or separated to control the flow.
Continuity Check - a test to determine whether electrical current flows continuously
throughout the length of a single wire or individual wires in a cable.
Continuous Vulcanization -simultaneous extrusion and vulcanization of rubber-like
wires in a cable.
Control Cable -a multicolor cable made for operation in control or signal circuits.
Copolymer -a polymer formed from two or more types of Monomers.
Copper-Clad -steel with a coating of copper welded to it, as distinguished from copper-
plated. Same as Copperweld.
Copperweld - the trade name of Felxo Wire Division (Copperweld Steel Corp.) for their
copper-clad steel conductors.
Cord - a small, flexible insulated cable.
Corona - a discharge due to ionization of air around a conductor due to a potential
gradient exceeding a certain critical value.
Corona Effect - in wiring, the effect produced when two wires of other conductors
having a great difference of voltage are placed near each other.
Corona Loss -A loss or discharge which occurs when two electrodes having a great
difference of pressure are placed near each other.
Corona Resistance -The time that the insulation will withstand a specific level of field-
intensified ionization that does not result in the immediate complete breakdown of the
Corona Test -A test to determine the ability of cable to withstand the formation of the
corona under an increasing applied voltage and the extinguish corona when a corona-
producing voltage is reduced.
Corrosion - The deterioration of a material by chemical reaction or galvanic action.
CPE - jacketing compound based on chlorinated polyethylene.
Crazing - the minute crack on the surface of plastic materials.
CRCS - an acronym for continuous rigid cable support. Synonymous with tray.
Creep - The dimensional change with time of a material under load.
Creepage - Electrical leakage on a solid dielectric surface.
Cross-linked - inter-molecular bonds between long chain thermoplastic polymers by
chemical or electron bombardment means. The properties of the resulting thermosetting
material are usually improved.
Crosstalk - A type of interference caused by signals from one pair or cable being
coupled into adjacent pairs or cables. Can occur with audio, data, or RF signals.
C.S.A -Abbreviation for Canadian Standards Association, the Canadian version of the
Cure -See Vulcanization
Curl -The degree to which a wire tends to form a circle after removal from a spool. An
indication of the ability of the wire to be wrapped around the posts in long runs.
Current - the rate of flow of electricity in a circuit, measured in amperes.
Current-Carrying Capacity -the maximum current an insulated conductor or cable can
continuously carry without exceeding its temperature rating. It is also called ampacity.
Current Penetration -the depth a current of a given frequency will penetrate into the
surface of a conductor carrying the current.
Cut-Through -Resistance of solid material to penetration be an object under conditions
of pressure, temperature, etc.
CV (Continuous Vulcanization) - simultaneous extrusion and vulcanization of wire
Cycle -The complete sequence of alteration or reversal of the flow of an alternation
D.C. - abbreviation of "Direct Current"
Decibel (dB) -A unit to express differenced of power level. Used to express power gain
in amplifiers or power loss in passive circuits or cables.
Delay Line - A transmission line or equivalent device designed to delay a wave or
signal for a specific length of time.
Derating Factor - A multiplier used to reduce the current carrying capacity of
conductors in more adverse environments, such as higher temperature, or where
multiple conductors are together in one conduit.
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
conductors plus any surrounding air or other material.
conductor and the outer conductor. In twisted pair cables it is the insulation between
Dielectric Absorption -That property of an imperfect dielectric whereby there is an
accumulation of electric charges within the body of the material when it is placed in an
Dielectric Breakdown -The voltage at which a dielectric material is punctured, which is
divisible by thickness to give dielectric strength.
Dielectric Constant (K) - 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 Strength - The voltage an insulation can withstand before it breaks down.
Usually expressed as "volts per mil".
Dielectric Test - a test in which a voltage higher than the rated voltage is applied for a
specific time to determine the adequacy of the insulation under normal conditions.
Direct Burial Cable - A cable installed directly in the earth.
Direct Capacitance - The capacitance measured directly for conductor to conductor
through a single insulation layer.
Direct Current (DC) - An electric current which flows in only one direction.
Direct Current Resistance. (D.C.R) - The resistance offered by any circuit to the flow
of direct current.
Dissipation Factor - The tangent of the loss angle of the insulating material (Also
referred to as loss tangent, tan S and approximate power factor.
Double Foot -Combined length of one linear foot of paired material; i.e., one double
foot is equal to one foot of positive material plus one foot of negative material. Usually
used in determining thermocouple wire loop resistance.
Drain Wire - In a cable, the un-insulated wire in intimate contact with a shield to provide
for easier termination of such a shield to a ground point.
Drawing - In wire manufacturing, pulling the metal through a die or series of dies to
reduce diameter to a specified size.
Drum Packed - The method of coiling wire into fiber drums for shipment.
Duct - An underground or overhead tube for carrying electrical conductors.
Duplex Insulated - In the thermocouple industry, a combination of dissimilar metal
conductor of a thermocouple or thermocouple extension wire.
Eccentricity - Like concentricity a measure of the center of a conductor's location with
respect to the circular cross section of the insulation. Expressed as a percentage of
displacement of one circle within the other.
ECTFE - Ethylene chloro - trifluoroethylene (Halar)
EIA - Abbreviation for Electronic Industries Association
Elastomer - A rubber like substance
Electromagnetic - Pertaining to the combined electric and magnetic fields associated
with movements of electrons through conductors
Electromotive Force (e.m.f.) -Pressure or voltage. The force which causes current to
flow in a circuit.
Electrostatic -Pertaining to static electricity or electricity at rest. A constant intensity
Elongation - The fractional increase in length of a material stressed in tension.
Embossing -a marker identification by means of thermal indentation leaving raised
lettering on the sheath material of cable.
Emergency Overload - load which occurs when larger than normal currents are carried
through a cable or wire over a certain period of time.
EMI - abbreviation for Electromagnetic Interference.
Energize -to apply rated voltage to a circuit or device in order to activate it.
Equilay -more than one layer of helically laid wire with the direction of lay reversed for
successive layers, both with the length of lay the same for each layer.
Etched Wire -a process applied to fluroplastic wire in which the wire is passed through
a sodium bath to create a rough surface to allow epoxy resin to bond the fluroplastic.
ETFE -Ethylene tetrafluoroethylene (Teflon)
Ethylene Propylene Rubber (EPR) - an ozone resistance rubber consisting primarily of
ethylene propylene copolymer (EPM) or ethylene propylene diene terpolymer (EPDM).
ETPC - abbreviation for electrolytic tough pitch copper. It has a minimum conductivity of
External interference - the effects of electrical waves or fields which cause sounds
other than the desired signal (static).
Extrusion -the process of continuously forcing both a plastic or elastomer and a
conductor core through a die, thereby applying a continuous coating of insulation or
jacket to the core or conductor.
Fatigue Resistance - resistance to metal crystallization which leads to conductress or
wires breaking from flexing.
FEP -fluorinated Ethylene Propylene is a "Teflon" fluorocarbon resin and is a registerd
trademark of the DuPont Compnay. This is a melt extrudable fluorocarbon resin.
Fiber - A single, separate optical transmission element characterized by core and
Fiber Dispersion -(fiber optic) pulse spreading in a fiber cause by differing transit
times of various modes.
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
Field -An area through which electric and/or magnetic lines of force pass.
Filled Cable -a telephone cable construction in which the cable core is filled with a
material that will prevent moisture from entering or passing through the cable.
Filler - Nonconducting components cabled with the insulated conductors or optical
fibers to impart roundness, flexibility, tensile strength, or a combination of all three, to
Film - a thin plastic sheet.
Flame Resistant - The ability of a material not to fuel a flame once the source of heat is
Flammability -the measure of the material ability to support combustions.
Flammability Test -A test to determine the ability of a cable to resist ignition when
placed neat a source of heat of flame and to self-extinguish when removed from this
Flat braid -a woven braid of tinned copper strands rolled flat at time of manufacture to
a specified time.
Flat Cable -a cable with two smooth or corrugated but essentially flat surfaces.
Flat Conductor -a wire having a rectangular cross section as opposed to round or
Flat Conductor Cable - a cable with a plurality of flat conductors.
Flex Life -the measurement of the ability of a conductor or cable to withstand repeated
Flexible -the quality of a cable or cable component which allows for bending under the
influence of outside force, as opposed to limpness which is bending due to the cable's
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.
Foamed Plastic - insulations having a cellular structure.
FR-1 -a flammability rating established by Underwrites Laboratories for wires and
cables that pass a specially designed vertical flame test. The designation has been
replaced by VW-1.
Frequency - The number of times a periodic action occurs in one second. Measured in
Fuse Wire -Wire made from alloy that melts at a relatively low temperature.
Fused Spiral Tape -a PTFE Insulated hookup wire. The spiral wrapped conductor is
passed through a sintering oven where overlaps are fused together.
Galvanometer -an instrument used for detecting or measuring small electrical current.
Gas Filled Cable -a self-contained pressure cable in which the pressure medium is an
inert gas having access to the insulation.
Gauge -a term used to denote the physical size of a wire
Giga -a numerical prefix denoting one billion.
Ground - a conducting connection between an electrical circuit and the earth or other
large conductions body to serve as an earth thus makes a complete electrical circuit.
Halar -a trade name of Allied Chemical for their copolymer of ethylene and
chlorotriflurorethylene. Abbreviation ECTFE
Hard Drawn Copper Wire -Copper wire that has not been annealed after drawing.
Harness -an arrangement of wires and cables, usually with many breakouts, which
have been pulled together or pulled into a rubber or plastic sheath, used to interconnect
an electric circuit.
Hash Mark Stripe - a non-continuous helical stripe applied to a conductor for
Heat Distortion -Distortion or flow od a material of configuration due to application of
specific physical or electrical test.
the time of heart aging that a material can withstand before failing a
Heat Resistance -ability of a substance to maintain physical and chemical identity and
electrical integrity under specified temperature conditions.
Heat Seal -a method for sealing by thermal fusion.
Heat Shock - a test to determine stability of a material by sudden exposure to a high
temperature for a short period of time.
Helical Stripe - a continuous, colored spiral stripe applied to a conductor for circuit
Henry - Unit of inductance such that the induced voltage in volts is numerical equal to
the rate of change in current in amperes per second.
Hermetically Sealed -a gaslight enclosure that has been completely sealed by fusion
or other comparable means.
Hertz (Hz) -a term replaced cycles-per-second as a unit of frequency.
Hi Pot - a test designed to determine the highest voltage that can be applied to a
conductor without electrically breaking down the insulation.
High Voltage -generally, a wire or cable with an operating voltage of over 35,000 volts.
Hook-up Wire - a single insulated conductor used for low current, low voltage (usually
under 600 volts) applications within enclosed electronic equipment.
Hot Tin Dip - a process of passing bare wire through a bath of molten tin to provide a
Hygroscopic - capable of absorbing and retaining moisture.
Hypalon -DuPont's trade name for their chlorosulfonated polyethylene, an ozone
resistant synthetic rubber.
Hz - Abbreviation for Hertz.
IEC - International Electrotechnical Commission, similar to the ISO in structure and
IEEE -Institute of Electrical and Electronics Engineers.
Impendence -The total opposition that a circuit offers to the flow of alternating current
or any other varying current at a particular frequency.
IMSA -International Municipal Signal Association Specifications for Fire Alarm Cable.
Induced Current -an electrical current set up in a circuit by butting line of force; a
current caused by electromagnetic induction.
Inductance -The property of wire which stores electrical current in a magnetic field
around the wire. By coiling wire, the effect can be intensified. It is measured in Henrys.
Inductive Coupling -crosstalk resulting form the action of the electromagnetic field of
one conductor on the other.
Insulation - A material having good dielectric properties which is used to separate close
electrical components, such as cable conductors and circuit components.
Insulation Level 100% - Cable for use on grounded systems or where the system is
provided with relay protection such that ground faults will be cleared as rapidly as
possible but in any case within one minute.
Insulation Level 133% - Cable for use on grounded systems or where the faulted
section will be de-energized in a time not exceeding one hour.
Insulation Resistance ( I.R.) - That resistance offered by and insulation to an
impressed DC voltage, tending to produce a leakage current through the insulation.
Insulation Thickness - The wall thickness of the applied insulation.
Interconnecting Cable -the wiring between modules, between units, or the larger
portions of a system.
Interference -and undesired electrical signal induced into a conductor by electrical or
Interstices - voids or valleys between individual strands in a conductor by electrical or
Ionization -The formation of ions. Ions are produced when polar compounds are
dissolved in a solvent and when a liquid, gas, or solid is caused to lose or gain electrons
due to the passage of an electric current.
ISA -Instrument Society of America
ISO - International Standards Organization
Jacket -Pertaining to wire and cable, the outer protective covering that may also
provide additional insulation.
JAN Specification -Joint Army-Navy specifications (forerunner of present Military
Jumper Cable -a short flat cable interconnecting two wiring boards or devices
Kilo -A numerical prefix denoting 1000.
KV - Kilovolt (1000 volts)
KVA -Kilovolt ampere.
Kynar - Penwalt trade name for polyvinylidene flouoride. Typically used as insulation for
wire wrap wire.
Lacquer -a liquid resin or compound applied to textile braid to prevent fraying, moisture
Laminated Tape - a tape consisting of two or more layers of different materials bonded
LANCE - Local Area Network for Controller Ethernet
LANS -Local Area Networks System (integration of computer and communication).
System that wires together all computers and peripherals in an office so they can talk to
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.
Lay Direction - the twist on the cable as indicated by the top strands whole looking
along the axis of the cable away from the observer. Described as "right hand" or "left
Leaching and Non-Leaching -in a leaching wire the plasticizer will migrate when
exposed to heat. A non-leaching wire will retain its plasticizer under extreme
temperature conditions and remain flexible after baking.
Leakage Current - the undesirable flow of current through or over the surfaces of an
Life Cycle - a test to determine the length of time before failure in a controlled, usually
Limits of Error - the maximum deviation (in degrees or percents) of a thermocouple or
thermocouple extension wire from standard emf-temperature to be measured.
LOCA -abbreviation for Loss of Coolant Accident, a system malfunction associated
with nuclear generation stations.
Local Area Network - a baseband or broadband interactive bi-directional
communication system for information exchange on a common transmission line.
Longitudinal Shield - a tape shield, flat or corrugated, applied longitudinally with the
axis of the core being shielded.
Longitudinal Wrap -tape applied longitudinally with the axis of the core being shielded.
Loop Resistance - the total resistance of two conductors measured round tip from one
Loss Factor -the product of the dissipation and dielectric constant of an insulation
Low Noise Cable - cable configuration specifically constructed to eliminate spurious
electrical disturbances caused by capacitance changes of self-generated noise induced
by either physical abuse or adjacent circuitry.
Low Loss Dielectric -an insulation material that has a relatively low dielectric loss,
such as polyethylene or Teflon.
Low Tension -low voltage, as applied to ignition cable.
Magnetic Field - the region within which a body or current experiences magnetic
Magnetic Flux - the rate of flow of magnetic energy across or through a surface (real or
Magnetic Noise - caused my change in current level, e.g., AC powerline (created
magnetic field around that cable) this magnetic field causes the magnetic noise.
MC Metal-Clad Cable -NEC type designation for power and control cables enclosed in
a smooth metallic sheath, welded and corrugated metallic sheath, or an interlocking
MCM - one thousand circular mils.
Megarad - a unit for measuring radiation dosage, Equal to one million rads.
Megohm -one million ohms.
Member -a group of insulated wires to be cabled with other stranded groups into
Messenger- the linear supporting member, usually a high strength steel wire, used as
the supporting element of a suspended aerial cable. The messenger may be an integral
part of the cable, or exterior to it.
Mho - the unit of conductivity. The reciprocal of an ohm.
Muticonductor - more than one conductor within a single cable complex.
Mutual Capacitance - capacitance between two conductors when all other conductors
including ground are connected together and then regarded as an ignored ground.
Mutual Inductance - the ratio of voltage induced on one conductor to the time tae of
current change in the separate conductor causing this induction.
MW -radio hookup wire with polyvinyl insulation and plain or nylon jacket, braid, or
Mylar -DuPont trademark for a polyester material used in the form of a tape.
National Electric Code (NEC) -a consensus standard published by The National Fire
Protection Association (NFPA) and incorporated in OSHA regulations.
NBFU -National Bureau of Fire Underwriters. NBS - National Bureau of Standards.
NEC - See National Electric Codes.
NEMA - National Electrical Manufacturers Association.
Neoprene - trade name for polychloroprene synthetic rubber, used for jacketing when
Noise - in a cable or circuit, any extraneous signal which tends to interfere with the
signal normally present in or passing through the system.
Nominal O.D. - the desired diameter for a cable that is established within a +/
Non-Contaminating -type of PVC jacket material whose plasticizer will not migrate into
the dielectric of a coaxial cable and thus avoids contaminating and destroying the
Non-Contaminating PVC - a polyvinylchloride formulation, which does not produce
electrical contamination through plasticizer migration.
Nylon - a group of polyamide polymer which is used for wire and cable jacketing.
O.D. -outside diameter.
Off-center - conductor displaced within the cross-section of its insulation.
Offgassing -percentage of a specified gas releases during the combustion of insulation
or jacketing material.
OFHC -abbreviation for oxygen-free high conductivity copper. It has no residual
deoxidant, 99.95% minimum copper content and an average annealed conductivity of
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.
Oil Aging -cable aged in an accelerated manner by placement in an oil bath and
heated to a pre-set temperature fr a stated time.
Oil-Filled Cable -a self-contained pressure cable in which the pressure medium is low
viscosity oil having access to the insulation.
Outgassing - the dissipation of gas from a dielectric evidencing decomposition.
OVE -approval agency of West Germany; Osesterreichischer Verband fur
Overall Diameter -finished diameter over wire and cable.
Overcoat - individual strands of tin copper stranded together and then covered with a
Overlap - the amount the trailing edge laps over the leading edge of a tape wrap.
Oxygen index -percentage of oxygen necessary to support combustion of a specified
Ozone -a highly active form of oxygen produced by the passage of electric discharges
or sparks through the air or oxygen.
Pair -two insulated wires of single circuit associated together.
Pairing -the union of two insulated single conductors through twisting.
Parallel Cable - two insulated conductor's side-by-side in a cable.
Peak Voltage - the maximum instantaneous voltage.
Percent Conductivity - conductivity of a material expressed as a percentage of that of
Periodicity - The uniformly spaced cable impedance variations that result in addition of
the reflections of a signal. The distance between them is the half wavelength most
affected. Multiples of that frequency is also affected. Even very slight variations, which
appear over and over in a construction or installation, can have major effects on signal
integrity because of periodicity.
Permittivity -see dielectric constant
Pick - distance between two adjacent crossover points of braid filaments. The
measurement in picks per inch indicates the degree of coverage.
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. Spacing.
Pitch Diameter -diameter of a circle passing through the center of the conductors in
any layer of multiconductor cable.
Planetary Cabler -a cabler of laying down any number of shielded, over braided or
jacketed singles, pairs, called groups or any combination of them in a sequence.
Planetary Twister -a twisting machine whose payoff spools are mounted in rotating
cradles that hold the axis of the spool in a fixed direction as the spools are revolved so
the wire will not kink as it is twisted.
Plastic Deformation - change in dimensions under the load that is not recovered when
the load is removed.
Plasticizer -a chemical agent added to plastics to make them softer and more pliable.
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.
Plenum Cable - cable approved by Underwriters Laboratories for installation in
plenums without the need for conduit.
PLTC -NEC type designation for Power-Limited Tray Cable for use in class 2 or 3
Power-Limited circuits; instrumentation supervisory control, and thermocouple
Polyester -Polyethylene terephthalate which is used extensively in the production of a
high strength moisture resistant film used as a cable core wrap.
Polythylene -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
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.
Polypyopylene -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.
Polyvinyl Chloride (PVC) - A general purpose thermoplastic used for wire and cable
insulation and jackets.
Porosity -multiple air voids in an insulation jacket wall.
Power Factor -the ratio of resistance to impedance. The ratio of the actual power of an
alternating current to apparent power. Mathematically, the cosine of an angle between
the voltage applied and the current resulting.
PPE -Portable Power Elastomer. Same as Type W except is a thermoplastic elastomer
insulation and jacket whereas Type W is all thermoset.
Pre-Bond - stranded wire which has been fused, topcoat tinned, or overcoat tinned.
Primary Insulation - the first layer of nonconductive material applied over a conductor,
whose prime function is to act as electrical insulation.
Progpagation Delay -Time required for a signal to pass from the input to the output of
Propagation Time - time required for a signal to pass from the input to the output of a
PTFE -abbreviation for Polytetrafluoroethylene.
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.
Pulse Cable - a type of coaxial cable constructed to transmit repeated high voltage
pulses without degradation.
PVD - Polyvinylidene fluoride (Kynar).
Pyrometer - see thermocouple thermometer.
Quad -a four conductor cable.
Quadders - three-bay machines which can twist four wires together and cable braided
and shielded wires with varying lay lengths.
QPL - Qualified parts list.
Rad - the unit of radiation dose which is absorbed, equal to 100 ergs/gram.
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.
Reference Junction - the junction of a thermocouple which is as a known reference
temperature. Also known as the "cold" junction,. It is usually located at the emf
Reflection Loss - The part of a signal which is lost due to reflection of power at a line
Registration - Alignment of one object with relation to another. In flat cables it involves
aligning conductors with contacts or solder pads. Also called register.
Resin -an organic substance of natural or synthetic origin characterized by being
polymeric in structure and predominantly amorphous. Most resins, through not all, are of
high molecular weight and consist of long chain or network molecular structure.
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.
Retractile Cable -a cable that returns by its own stored energy from an extended
condition to it original contracted form.
RFI - Radio Frequency Interference.
RG/U -RG is the abbreviation for radio guide, a military designation for a coaxial cable,
and U stands for universal.
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.
Ridge maker -one or more ridges running laterally along the outer surface of the
plastic insulated wire for purposes of identification.
Ringing Out - The process of locating or identifying specific conductor paths by means
of passing a current through selected conductors.
Rise Time - the time required for the initially zero potential existing on a transmission
line (which is terminated in its characteristics impendence) to change from 10% to 90%
of its full DC value after a DC potential source is instantaneously applied.
RMS or rms - Root-mean-square.
Rockwell Harness - a test for determining hardness in which a hardened steel ball or
diamond point is pressed into the material under test.
Roentgen - the amount of radiation that will produce on electrostatic unit of ion per
cubic centimeter volume.
Rope Lay Conductor -a conductor composed of a central core surrounded by one or
more layers of helically laid groups of wire.
Rope Strand -A conductor composed of groups of twisted strands.
Round Conductor - a conductor whose cross section is substantially circular.
Rulan - DuPont's trade name for their flame-retardant polyethylene insulating material.
Rupture - in the breaking strength or tensile strength tests, the point at which the
material physically comes apart, as opposed to elongation, yield strength, etc.
SAE -Society of Automotive Engineers.
SBR -A copolymer of styrene and butadiene. Also GR-S or Buna-S. Most commonly
used type of synthetic rubber.
SDN - small diameter multi-conductor control cable with a neoprene jacket and nylon
sheath over polyethylene insulation.
Secondary insulation -a high resistance dielectric material which is placed over
primary insulation to protect it from absorption.
Self Extinguishing - The characteristic of a material that extinguishes its own flame
after the igniting flame is removed.
Self-Supporting Cable - any assemblage of conductors which incorporates a steel
rope of steel sheath for added tensile strength, thus enabling it to be suspended
between widely spaced supports.
Semi-Conducting Tape - a tape of such resistance that when applied between two
elements of a cable, the adjacent surfaces of the two elements will maintain
substantially the same potential.
Semiconductor - 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.
Semi-Rigid PVC - a hard semi-flexible polyvinylchloride compound with low plasticizer
SEMKO - approval agency for Sweden .
Separator -a layer of insulating material such as textile, paper, polyester, etc. Used to
improve stripping qualities, flexibility, mechanical or electrical protection to the
Serve - a filament or group of filaments such as fibers or wires, wound around a central
Served Wire Armor -spiral wrap of soft galvanized steel wires wrapped around a cable
to afford mechanical protection and increase the cable pulling tension characteristics.
SEW, SEWF - Silicone Rubber insulated equipment wire (CSA).
SF -Silicone rubber insulated fixture wire, solid or 7 strand conductors, 200C.
SFF -same as SF, except flexible stranding, 150C.
Sheath -the outer covering or jacket of a multi-conductor cable.
SHD-GC - portable mine power cable, three or four individually shielded conductors,
with grounding conductors, 500V.
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
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.
Shock Test -a test to determine the ability of a cable to withstand a violent physical
concussion such as might occur during handling or use.
Shore Hardness - an instrument measure of the surface hardness of an insulating or
Signal -Any visible or audible indication which can convey information. Also, the
information conveyed through a communication system.
Signal Cable -a cable designed to carry current of the usually less than one ampere
Sintering - fusion of a spirally applied tape wrap jacket by the use of high heat to a
homogeneous continuum. Usually employed for fluorocarbon, non-extrudable materials.
SIS -indicated single conductor having synthetic thermosetting insulation of heat-
resistant, moisture-resistant, flame retarding grade. Also made with chemically cross
linked polyethylene insulation. Used for switchboard wiring only, 90C.
Skin Effect - The tendency of alternating current to travel only on the surface of a
conductor as its frequency increases.
SNM - a cable designed for the use in hazardous locations consisting of insulated
conductors in an extruded nonmetallic jacket which is then covered with an overlapping
spiral metal tape and wire shield and jacketed with an extruded moisture flame, oil,
corrosion, fungus and sunlight resistant nonmetallic material.
SO - hard service cord, same construction as type S except oil-resistant neoprene
jacket. 600V, 60C, and 90C.
Solid Conductor -a single unit not divided into parts.
SOW -water resistant neoprene jacketed portable cord (CSA).
SOW-A/SOW - service cord with oil resistant jacket and weather resistant. Also is water
Spacing - The distance between the centers of two adjacent conductors. Pitch.
Spark Test - a test that is designed to locate imperfections (usually pin-holes) in the
insulating 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
Specific Inductive Gravity (S.I.C) -same as dielectric constant.
Spiral Wrap -the helical wrap of a material over a core.
ST - hard service cord, jacketed, same as type S except all-plastic construction, 600V,
60C to 105C.
STOO - same as STO but with oil-resistant thermoplastic outer jacket. 600V, 60C.
-service cord with oil resistant Thermoplastic jacket and weather resistant. STOW-A
meets CSA approval for outdoor use. Can be water resistant -UL 600V
-service cord with Thermoplastic, and weather resistant jacket, but no oil resistant. Can
me UL water resistant. STW-A meets CSA approval for out door use 600V
Stability Factor - the difference between the percentage power factor at 8-colts/mil
and at 40 volts/mil measured on wire immersed in water at 75C for a specified time.
Stranding Wave - the stationary pattern of waves produced by two waves of the same
frequency traveling in opposite directions on the same transition line. The existence of
voltage and current maxima and minima along a transmission line is a result of reflected
energy for an impedance mismatch
Standing Wave Ratio - a ratio of the maximum amplitude to the minimum amplitude of
a standing wave stated in current or voltage amplitude
Static Condition - used to denote the environmental conditions of an installed cable
rather than the conditions existing during LAN installation.
Strand -a single un-insulated wire.
Stranded Conductor - a conductor composed of individual groups of wires twisted
together to form an entire unit.
Strip Force -the force required o remove a small section of insulating materials from
the conductor it covers.
Suggested Working Voltage - AC voltage that can be applied between adjacent
Surface Resistively - the resistance of a material between two opposite sides of a unit
square of its surface. It is usually expressed in ohms.
Surge - A temporary and relatively large increase in the voltage or current in an electric
circuit or cable. Also called transient
Surlyn - DuPont's trade name for their thermoplastic resin with ionic crosslink's
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).
Switchboard Cable -a cable used within and between the central office main frames
and the switchboard.
Take-Up - the process of accumulating wire or cable into a reel, bobbin, or some other
type of pack. Also, the devise for pulling wire or cable through a piece of equipment or
Tank Test - a voltage dielectric test in which the test sample is submerged in water and
voltage is applied between the conductor and water as ground
Tape Wrap - a spirally applied tape over an insulated or non-insulated wire
TC - Tray cable. Article 340 NEC.
Tear Strength - the force required to initiate or continue a tear in a material under
Teflon -DuPont Company trademark for fluorocarbon resins. (FEP -Fluorinated
and chemical and heat resistance.). (TFE - Tetrafluoroethylene. A thermoplastic
material with good electrical insulating properties and chemical and heat resistance.). It
ethylene-propylene. A thermo-plastic material with good electrical insulating properties
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.
Telemetry Cable -cable used for transmission of information from instruments to the
peripheral recording equipment
Temperature Rating -The temperature range in which a material will perform its
function without undue degradation.
Tensile Strength -the pull stress required to break a given specimen.
Tension Member -a member included on a fiber cable to add tensile strength
Terminals - metal wire termination devices designed to handle one or more conductors,
and to be attached to a board, bus, or block with mechanical fasteners or clipped on.
Teat Lead - a flexible, insulated lead wire used for making tests, connecting instruments
to a circuit temporarily, or for making temporary electrical connections.
TEW -Canadian Standards Association type appliance wires. Solid or stranded single
conductor, plastic-insulated 600V, 105C
Textile Braid -any braid made from threads of cotton, silk, or synthetic fibers.
TFFN -fixture wire, thermoplastic-covered solid or 7 strands with nylon sheath. 60C
Thermal Aging -exposure to a thermal condition of programmed series of conditions
for pre-described periods of time
Thermal Rating - the maximum and/or minimum temperature at which a material will
perform its function without undue degradation.
Thermal Shock -a test to determine the ability of a material to withstand heat and cold
by subjecting it to rapid and wide changes in temperature
Thermocouple -a device consisting of two dissimilar metals in physical contact, which
when heated will develop an emf output
Thermocouple Element - a thermocouple designed to be used as part of an assembly,
but without associated parts such as the terminal block, connecting head, or protection
Thermocouple Extension Cable - a cable comprised of one or more twisted
thermocouple extention wires under a common sheath.
Thermocouple Extension Wire -a pair of wires of dissimilar alloys having such emf-
temperature characteristics complementing the thermocouple which is intended to be
used, such that when properly connected allows the emf to be faithfully transmitted to
the reference point.
Thermocouple Wire (Grade) -a pair of wires of dissimilar alloys having emf-
temperature characteristics calibrated to high temperature levels than the extension
type of thermocouple wires
Thermoplastic -A material which will soften, flow, or distort appreciably when
subjected to sufficient heat and pressure. Examples are polyvinyl chloride and
Thermostat -a material which hardens or sets by heat, chemical or radiation
crosslinking techniques and which, once set, cannot be re-softened by heating.
THHN -90C, 600 volt, nylon jacketed building wire for dry locations.
THW -thermoplastic vinyl insulated building wire. Flame-retardant, moisture and heat
resistant. 75C Dry and wet locations.
THWN -same as THW but with nylon jacket overall. 75C
Tin Overcoat (TOC) -tinned copper wire, stranded, then coated with pure tin.
Tinned Copper - tin coasting added to copper to aid in soldering and inhibit corrosion.
Topcoat - bare (untinned) copper wire, stranded, then coated with pure tin.
Tracer - a means of identifying polarity.
Transfer Impedance - for a specified cable length, transfer impendence is defined as
the ratio of internal longitude in a voltage to external current flow on the cable shield.
Transfer impendence is used to determine shield effectiveness against both the ingree
and egress of interfering signals.
Transmission - transfer of electric energy from one location to another through
conductors or by radiation or induction fields.
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 Loss - the decrease or loss in power during transmission of energy from
one point to another. Usually expressed in decibels.
Tray -a cable tray is a unit or assembly of units or sections, and associated fittings,
made of noncombustible materials forming a rigid structural system used to support
Tray Cable -a factory-assembled muticonductor or multipair control, signal or power
cable specifically approved under the National Electric Code for installation in trays
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.
Triboelectric Noise -Noise generated in a shielded cable due to variations in
capacitance between the shield and conductors as the cable is flexed.
Triple (Triad) -a cable consisting of three insulated single conductor cables twisted
Triplex - a cable composed of three insulated single conductor cables twisted together.
Twin Cable -a cable composed of two separately insulated stranded conductors laid
parallel or twisted together.
Twin Coaxial Cable -a single cable consisting of two separate coaxial cables laid
adjacent and parallel or twisted together.
Twin Line -a transmission line which has a solid insulating material, in which the two
conductors are placed in parallel to each other.
Twinner - a device for twisting together two conductors.
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.
Twisted Triad - any three individually insulated conductors which are twisted together
UHF -abbreviation for ultra high frequency, 300 to 3,000 Mhz.
UL - Underwriters Laboratories. A nonprofit organization which tests and verifies
construction and performance of electronic parts and equipment, including wire and
Unbalanced Circuit -a transmission line in which voltages on the two conductors are
unequal with respect to ground; e.g., a coaxial cable
Unidirectional Concentric Stranding -a stranding where each successive layer has a
different lay length, thereby retaining a circular from without migration of strands from
one layer to another
Unilay -more than one layer of helically laid wires with the direction of lay and length of
lay the same for all layers.
Valley -any void between the insulated conductors of cable or between a cable core
and it's covering. See also interstice
Velocity of Propagation -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 Pair Cable -a transmission cable containing low-loss pairs with impedance of
125 ohms. Used for TV pick ups, closed circuit TV, telephone carrier circuits, etc
Volt -A unit of electromotive force.
Voltage - Electrical potential of electromotive force expressed in volts.
Voltage Levels -power-limited 0-300 volts, low voltage 600-2000 volts, medium
voltage 5000-69000 volts.
Voltage Rating - The highest voltage that may be continuously applied to a cable
construction in conformance with standards or specifications
Voltage Stranding Wave Radio (VSWR) - the ratio of the maximum effective voltage to
the minimum effective voltage measured along the length of miss-matched radio
frequency transmission line.
Volume Resistively (Specific Insulation Resistance) -the electrical resistance
between opposite faces of a 1 cm. cube of insulating material, commonly expressed in
Vulcanization - an irreversible process during which a rubber or polymeric compound
through a change in its chemical structure (for example, crosslinking) become
VW-1 - A flammability rating established by Underwriters Laboratories for wires and
cables that pass a specially designed vertical flame test, formerly designed FR-1.
Wall Thickness -The thickness of an insulation or jacket.
Water Absorption - water by percent weight absorbed by a material after a given
Water Blocked Cable -a cable constructed with no internal voids in order to allow no
longitudinal water passage under given pressure.
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.
Wicking - the longitudinal flow of a liquid in a wire or cable due to capillary action.
Wire -a single conductor, typically with a covering of insulating.
Wire Gauge - a measure of the diameter or size of wires. The sizes are expressed by
Working Voltage - see voltage rating
XHHW -high temperature (90C) chemically cross-linked polyethylene jacketed small
diameter building wire.
XLP -Cross-linked polyethylene
Yield Strength - the minimum stress at which a material will start to physically deform
without further increase in load.
Z-Symbol for impedance
ZW -NEC conductor type designation for conductors with ETFE insulating for use in
wet or dry locations