Glossary of Terms
Use Calmont Wire & Cable’s Glossary of Terms to help define your project’s needs.
- A
- Ampere.
- Abrasion Resistance
- A measure of the ability of a wire, wire covering or material to resist surface wear or damage by mechanical means.
- AC
- alternating current.
- Accelerated Aging
- A cable or material is subjected to increased temperatures above normal operating values to obtain observable deterioration in a reasonable period of time, and thereby provide a relative measure of the probable cable or material life under operating temperature.
- Adjacent Conductor
- Any conductor next to another conductor in the same cable.
- Aging
- The change in properties of material with time.
- Alternating Current
- Electric current that periodically and regularly reverses its direction. The frequency of the change in flow is expressed in Hertz or Hz.
- Ambient Temperature
- The temperature of the area around an object before testing starts.
- American Wire Gauge (AWG)
- The standard system used for designating wire diameter. Also referred to as the Brown and Sharp (B & S) wire gauge.
- Ampere
- The unit expressing the rate of flow of an electrical current. One ampere is the current flowing through one ohm of resistance at one volt potential.
- Anneal
- To heat and then gradually cool in order to relieve mechanical stresses. Annealing copper makes it softer and less brittle.
- Arc Resistance
- Having restive properties to an arc establishing a conductive path.
- ASTM
- American Society for Testing and Materials.
- Attenuation
- Applied to coaxial cables, the signal loss in a circuit, expressed in decibels, dB.
- AWG
- American Wire Gauge.
- AWM
- Underwriters Laboratories designation for Appliance Wiring Material.
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- Balanced Line
- A cable having two conductors which carry voltages opposite in polarity but equal in magnitude with respect to ground.
- Balun
- A device for matching an unbalanced coaxial transmission line to a balanced two line system. A balun can also provide impedance transformation.
- Band Width
- The frequency range of electrical signals transmitted. Expressed in Hz.
- Bare Conductor
- A conductor not covered with insulating material.
- Baud
- Unit of data transmission speed. One Baud is one bit per second.
- Binder
- Spirally served tape or thread used for holding assembled cable components in place.
- Bond Strength
- Amount of adhesion between bonded surfaces.
- Braid
- Woven bare metallic or tinned copper wire used as shielding for wires and cables and as ground wire equipment. Can also be a woven fibrous protective outer covering over a conductor or cable.
- Braid Angle
- The angle between the axis of the cable and axis of the braid.
- Braid Carrier
- The spool or bobbin on a braiding machine which holds one group of strands or filaments consisting of a given number of ends.
- Braid Ends
- The strands used on one carrier.
- Breakdown
- A destructive discharge through the insulation.
- Breakdown Voltage
- The voltage at which the insulation between two conductors will break down.
- Brown & Sharp Gauge
- A wire diameter standard now referred to as AWG.
- Bunched Stranding
- Term applied to group of strands twisted together in a random manner in the same direction in one operation without regard to geometric arrangement of the strands.
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- C
- Celsius. A temperature rating system where water freezes at zero degrees and boils at one hundred degrees.
- Cable
- A combination of conductors insulated from one another (multiple-conductor cable).
- Cable Core
- The portion of an insulated cable under the protective covering or coverings.
- Cable Filler
- The material used in multiple-conductor cables to occupy the interstices in a cable to make the finished cable round.
- Cabling
- Twisting together two or more insulated conductors by machine to form a cable.
- Cabling Factor
- Used in formula for calculating the overall diameter of cable. D=fd where D=cable diameter, f=factor, and d=diameter of one conductor.
- Capacitance
- That property of a system of conductors and dielectrics which permits the storage of electricity when potential difference exists between the conductors. Its value is usually stated in Picofarads/foot.
- Cellular Insulation
- Insulation that has had an agent used to produce cells or “bubbles”. Used to reduce the dielectric constant of the solid insulation.
- Characteristic Impedance
- Characteristic impedance of a uniform line is ratio of an applied potential difference to the resultant current at the point where the potential difference is applied, when the line is of infinite length. Note that the term is applied only to a uniform line. Coaxial cable is such a uniform line. There are three main impedance groups in coaxial cable, namely, 50, 70, and 93 ohms.
- Cigarette Wrap
- Tape insulation wrapped longitudinally instead of spirally over a conductor.
- Circuit
- A complete path over which electrons can flow from the negative terminals of a voltage source through parts and wires to the positive terminals of the same voltage source.
- Circular Mil Area
- The diameter of a conductor in mils squared. The cross sectional area of a stranded conductor in Circular mils is calculated by multiplying the Circular Mil Area of a strand in the conductor by the number of strands.
- Cladding
- A method of applying a layer of metal over another metal whereby the junction of the two metals is continuously welded.
- Coating
- Plating surface of a conductor to prevent corrosion and facilitate soldering. One coating commonly used on copper wire is tin. Term can also apply to an insulating coating.
- Coaxial Cable
- A cable consisting of two cylindrical conductors with a common axis. The two conductors are separated by a dielectric. The outer conductor, normally at ground-potential, acts as a return path for current flowing through the center conductor and prevents energy radiation from the cable. The outer conductor, or shield, is also commonly used to prevent external radiation from affecting the current flowing in the inner conductor. The outer shield or conductor consists of woven strands of wire or is a metal sheath.
- Coil Effect
- The inductive effect caused by a spiral wrapped shield. This is more pronounced at higher frequencies.
- Cold Bend
- Test procedure whereby a sample of wire or cable is wound around a mandrel of a specified size within a cold chamber, at a specified temperature for a given number of turns at a given rate of speed. The sample is then removed and examined for defects or deterioration in the materials or construction.
- Cold Flow
- Permanent deformation of materials due to mechanical force or pressure (not due to heat softening).
- Cold Joint
- Soldered joint made with insufficient heat.
- Cold Work
- Hardening and embrittlement of metal due to repeated flexing action.
- Color Code
- A color system for wire or circuit identification by use of solid colors, tracers, braids, surface printing, etc.
- Compact Conductor
- Stranded conductor which is rolled to deform the round wires to fill the normal interstices between the wires in a strand.
- Composite (Clad) Wire
- A wire having a core of one metal with a fused outer shell of one or more different metals.
- Composite Conductor
- Two or more strands of different metals, such as aluminum and steel or copper and steel, assembled and operated in parallel.
- Compound
- An insulating or jacketing material made by mixing two or more ingredients, thereby resulting in one material.
- Concentric
- A central core surrounded by one or more layers of helically wound strands in a fixed round geometric arrangement. It is optional for the direction of lay for successive layers to be alternately reversed or in the same direction. If the direction of lay for successive layers is the same, the lay length shall increase with each successive layer. The standard direction of the outer layer is left hand.
- Concentric
- The direction of a layer with respect to the previous layer meaning a layer spiraling in an opposite direction than the preceding layer within a wire or cable.
- Concentric Strand
- A strand that consists of a central wire or core surrounded by one or more layers of spiral laid wires. Each layer after the first has six more strands than the preceding layer and is applied in a direction opposite to that of the layer under it.
- Concentricity
- In a wire or cable, the measurement of the location of the center of the conductor with respect to the geometric center of the circular insulation. Concentricity is measured by dividing the thinnest wall by the thickest wall and expressed as a percent.
- Concentric-Lay Cable
- Either: (a) A concentric-lay conductor as defined above, or (b) A multiple-conductor cable composed of a central core surrounded by one or more layers of helically laid wires. (Note: In the most common type of Concentric-Lay Conductor, all wires are of the same size and the central core is a single wire.)
- Conductance
- The reciprocal or resistance. It is the ratio of current passing through a material to the potential difference at its ends.
- Conductivity
- Reciprocal of volume Resistivity. Conductance of a unit cube of any material.
- Conductor
- A wire or combination of wires not insulated from one another, suitable for carrying electric current.
- Continuity
- A test performed on a length of finished wire or cable to determine if the electrical current flows continuously throughout the length. Each conductor may also be checked against each other to ascertain that no short exists.
- Continuous Vulcanization
- After a rubber or rubber like compound is extruded on to a conductor, the wire is then passed into a vulcanizing chamber where the insulation or jacket is continuously vulcanized under high pressure and temperature control.
- Control Cable
- A cable used for remote control operation of any type of electrical power equipment
- Controlled Impedance Cable
- Cable with two or more insulated conductors where impedance measurements between respective conductors are kept essentially constant throughout entire length.
- Copolymer
- A compound resulting from the chemical reaction of two chemically different monomers with each other.
- Copper
- Available in rod, sheet, foil, tube, and wire forms. On a volume basis, copper has the conductivity of the common (non-precious) metals. Copper and copper alloys offer excellent corrosion resistance, high thermal conductivity, and ease of fabricating, joining and forming. The strength to weight ratio of copper is relatively low and it loses strength at elevated temperatures. Copper is the most widely used electrical conductor in wires and cables. Some of the common types of electrical coppers and copper alloys are:
- Copper Constantan
- Copper and constantan are two alloys used in making thermocouples wires. The copper is the positive wire and the constantan is the negative wire. Constantan is an alloy of copper, nickel manganese, and iron.
- Copper-Covered Steel Wire
- A wire having a steel core to which is fused an outer shell of copper.
- Cord
- A small, very flexible insulated cable constructed to withstand mechanical abuse. (Note: There is no sharp dividing line in respect to size between a cord and a cable, but generally, a cord is considered to be a size No. 10 and smaller.)
- Cord Sets
- Portable cords fitted with any type of wiring device at one or both ends. Core In cables, a term used to express a component or assembly of components over which other materials are applied, such as additional components, shield, sheath, or armor.
- Corona
- A luminous discharge due to ionization of the gas surrounding a conductor around which exists a voltage gradient exceeding a certain critical value.
- CoronaResistance
- The time that insulation will withstand a specified level field-intensified ionization that does not result in the immediate, complete breakdown of the insulation.
- Corrosion
- Chemical action which causes destruction of the surface of metal by oxidation or chemical combination. Also caused by reduction of the electrical efficiency between the metal and a contiguous substance or to the disintegrating effect of strong electrical currents or ground return currents in electrical systems. The latter is known as electrolytic corrosion.
- Coulomb
- Unit quantity of electricity, i.e. the quantity transferred by one ampere in one second.
- Coverage
- The calculated percentage which defines the completeness with which a metal braid covers the underlying surface. The higher percentage of coverage, the greater the protection against external interference.
- Coverings
- Textile braids or jackets or rubber, plastics, or other materials applied over wire and cables to provide mechanical protection and perhaps identification.
- Crazing
- Minute cracks on or near the surface of materials such as plastics.
- Creep
- The dimensional change with time of a material under load.
- Creepage Surface
- An insulating surface which provides physical separation as a form of insulation between two electrical conductors of potential.
- Crimp
- Act of compressing (deforming) a connector barrel around a cable in order to make an electrical connection.
- Cross-Linking
- The setting-up of chemical links between the molecular chains.
- Cross-Sectional Area of a Conductor T
- he sum of the cross-sectional areas of its component wires, that of each wire being measured perpendicular to its individual axis.
- Crosstalk
- Signal interference between nearby conductors caused by the pickup of stray energy.
- CS-95
- Phelps Dodge High Performance Conductors trade name for extra high strength copper alloy.
- CSA
- Canadian Standards Association.
- Cure
- To change the physical properties of a material by chemical reaction, by the action oil heat and catalysts, alone or in combination, with or without pressure.
- Curing Cycle
- The time, temperature, and pressure required for curing.
- Current
- The rate of transfer of electricity. Practical unit is the ampere which represents the transfer of one coulomb per second.
- Current Carrying Capacity
- The maximum number of amperes (amps) that can flow through a conductor before it reaches its maximum rated temperature. Many factors determine actual current carrying capacity including conductor size, temperature, number of bundled conductors, air flow and insulation material and thickness. Therefore, the table below should only be used as a general guideline to determine actual performance.
- Cut-Through Resistance
- Resistance of solid material to penetration by an object under conditions of pressure, temperature, etc.
- CV
- Continuous vulcanization.
- Cycle
- The complete sequence including reversal of the flow of alternating electric current.
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- D.C.
- direct current.
- dB
- see decibel.
- dB Loss
- The loss of a signal in a conductor expressed in decibels.
- Decibel (dB)
- Unit to express differences of power level. Used to express power gain in amplifiers or power loss in passive circuits or cables.
- Delay Line
- A cable or component made to provide an electrical delay for transmitted signals.
- Denier
- A term that describes the weight of a yarn (not cotton or spun rayon) which in turn determines its physical size. Defined as the weight in grams of 9,000 yards of the yarn.
- Density
- Density is used to calculate the approximate weight of a given conductor per unit length. Due to the stranding make-up of a given conductor, the density can only yield a nominal value.
- Derating Factor
- A factor used to reduce a current carrying capacity of a wire when used in other environments from that for which the value was established.
- Dielectric
- (1) Any insulating medium which intervenes between two conductors and permits electrostatic attraction and repulsion to take place across it. (2) A material having property that energy required to establish an electric field is recoverable in whole or in part, as electric energy.
- Dielectric
- Test Tests which consist of the application of a voltage higher than the rated voltage for a specified time. The purpose is to determine the adequacy of insulating materials.
- 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 electric field.
- Dielectric Constant
- That property of a dielectric which determines the electrostatic energy stored per unit volume for unit potential gradient.
- Dielectric Loss
- Losses due to electric energy being transformed into heat in a dielectric when it is subjected to a changing electric field.
- Dielectric Strength
- The voltage which an insulating material can withstand before breakdown occurs, usually expressed as a voltage gradient (such as volts per mil).
- Digital Signal
- An electrical signal which consists of two distinct states, on and off.
- Dip Coating
- An insulating coating applied to the conductor by passing the conductor through an applicator containing liquid insulating medium. This method can be used for magnet wire.
- Direct Current
- An electric current which flows in only one direction.
- Direction of Lay
- The lateral direction in which the elements of a cable run over the top of the cable as they recede from an observer looking along the axis of the cable. ASTM symbols are used to indicate direction: S for left-hand, Z for right hand.
- Dissipation Factor
- The tangent of the loss angle of the insulating material.
- Disturbed Conductor
- A conductor that receives energy generated by the field of another conductor on an external source such as a transformer.
- Disturbing Conductor
- A conductor carrying energy that creates spurious signals in another conductor.
- Double Shield
- Two shields, one over the other.
- Double-Faced Tape
- Fabric tape finished on both sides with a rubber or synthetic compound.
- Drain Wire
- In a cable an uninsulated wire laid over the component or components and used as a ground connection.
- Drawing
- In the manufacture of wire pulling the metal through a die or series of dies for reduction of diameter to a specified size.
- Dual Coaxial Capable
- Two individually insulated conductors laid parallel or twisted and placed within an overall shield and sheath.
- Duplex Cable
- A cable composed of two insulated single conductor cables twisted together. (Note: The assembled conductors may or may not have a common covering of binding or protecting materials. See also Parallel Pair).
- Durometer
- A measuring device used to denote the hardness of soft materials such as rubber or plastic.
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- Eccentricity
- 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 center displacement of one circle within the other.
- EIA
- Electronic Industries Association.
- Elastomer
- A material which at room temperature stretches under low stress to at least twice its length and snaps back to original length upon release of stress.
- Electric Strength
- The maximum potential gradient that the material can withstand without rupture. The value obtained for the electric strength will depend on the thickness of the material and on the method and conditions of test.
- Electromagnetic Coupling
- The transfer of energy by varying a magnetic field. Inductive coupling.
- Electromotive Force (emf)
- Pressure of voltage. The force which causes current to flow in a circuit.
- Electronic Interconnecting Wire
- Wires or cables used to make external connections between various units of electronic equipment.
- Electrostatic Coupling
- The transfer of energy by varying an electrostatic field. Capacitive coupling.
- Electro-Tinned
- Electrolytic process of tinning wire using pure tin.
- 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 a cable.
- EMF
- electromotive force or voltage.
- Ends
- The number of wires or threads on a braider carrier.
- End-To-End Check
- Tests conducted on a completed wire and/or cable run to assure electrical continuity.
- Epoxy Resins
- Straight-chain resins based on ethylene oxide, its derivatives or homolog’s. Used for bonding, potting connectors, and for splicing in some in-field splicing kits.
- Ethylenechlorotrifluoroethlene (ECTFE)
- A copolymer similar to ETFE but has one of the four fluorine atoms replaced with chlorine.
- Ethylenetrifluoroethlene
- (ETFE). A copolymer of ethylene and tetrafluoroethylene.
- ETP
- Electrolytic Tough Pitch copper. See copper.
- External Interference
- The effects of any electrical waves or fields which cause sounds other than the desired signal. Static.
- Extrusion
- Method of forcing plastic, rubber, or Elastomer material through an orifice in more or less continuous fashion to apply insulation or jacketing to conductor or cable.
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- Farad
- Unit of Capacitance. The capacitance of capacitor which, when charged with one coulomb, gives a difference of potential of one volt.
- Fatigue Resistance
- Resistance to metal crystallization which leads to conductors or wires breaking from flexing.
- Feed Through
- Terminal or connector for walls or panels.
- FEP
- Fluorinated Ethylene Propylene.
- FEPB
- NEC designation for FEP insulated wire with glass or asbestos braid.
- Ferrous
- Composed of, or containing iron. A ferrous metal exhibits magnetic properties.
- Fiber
- A thread or threadlike structure such as glass yarn.
- Filament
- Fiber characterized by extreme length per unit weight.
- Filler
- Materials used in multiconductor cables to occupy the interstices formed by the assembled conductors. Also, a substance, often inert, added to a plastic to improve properties and/or decrease cost.
- Film
- Sheeting having a nominal thickness not greater than 0.010 inch.
- Flame Resistance
- Ability of the material to extinguish flame once the source of heat is removed.
- Flammability
- Measure of the material's ability to support combustion.
- Flashover
- A disruptive discharge around or over the surface of a solid or liquid insulator.
- Flat Braid
- A woven braid, usually composed of tinned copper strands, which is rolled flat at time of manufacture to a specific width depending upon construction. It is generally used as a high current conductor at low voltages.
- Flat Cable
- Any cable with two smooth or corrugated but essentially flat surfaces.
- Flat Conductor Cable
- A cable with a plurality of flat conductors.
- Flex Life
- The time of heat aging that an insulating material can withstand before failure when bent around a specific radius (used to evaluate thermal endurance). Also, ability of a conductor, wire, or cable to withstand repeated bending.
- Floating
- A circuit which has no connection to ground.
- Fluorinated Ethylene Propylene
- FEP is similar to polytetrafluoroethylene (described later) but has a melting point about 50© lower and slightly different physical properties. It is more easily processed than PTFE and is used as an insulation and jacketing material.
- Flux
- The rate of flow of energy across or through a surface. Also, a substance used to promote or facilitate fusion such as materials used to remove oxides from surfaces to be joined by soldering or welding.
- FM
- Frequency modulation
- Foamed Plastics
- Resins in flexible or rigid sponge formed with the cells closed or interconnected. Foamed insulation provides low dielectric constants and weight savings.
- Foaming agents
- Chemicals added to plastics and rubbers that cause them to assume a cellular structure.
- Frequency
- The number of times an alternating current repeats its cycle in one second.
- Fused Spiral Tape
- This refers to a type of PTFE insulation on a hookup wire or jacketed cable. The spiral wrap wire or cable is passed through a sintering oven where the overlaps are fused together.
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- Gage
- A term used to denote the physical size of a wire.
- Gauge
- See Gage.
- Gigahertz
- A unit of frequency equal to one billion Hertz.
- Glass
- Glass fibers are used in yarn servings, fillers, and braids, and as strength members. High tensile strength, non-flammability, flexibility, and resistance to moisture and high temperatures are characteristics of glass fibers. Dielectric properties and
- Gold
- Used primarily as a coating or plating medium because of its electrical properties. It is a very soft, ductile material which is noted for its resistance to corrosive media.
- GRND
- ground.
- Ground
- An electrical term meaning to connect to the earth or other large conducting body to serve as an earth thus making a complete electrical circuit.
- Ground Power Cable
- A cable assembly fitted with appropriate terminations to supply power to an aircraft from ground power unit.
- Ground Support Cable
- Cable construction, usually rugged and heavy, for use in ground support control or power systems.
- Ground Wire
- A conductor leading from radio equipment to an electrical connection with the ground.
- Grounded
- Connected to earth or to some conducting body that serves in place of the earth.
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- Halar
- Registered trademark of Ausimont U.S.A., Inc.
- Halon
- Registered trademark of Ausimont U.S.A., Inc.
- Hard Drawn Copper Wire
- Copper wire that has not been annealed after drawing.
- Harness
- A group of conductors laid parallel or twisted by hand, usually with many breakouts, laced or bundled together.
- Heat Distortion
- Distortion or flow of a material or configuration due to the application of heat.
- Heat Endurance
- The time of heat aging that a material can withstand before failing a specific physical test.
- Heat Seal
- In cabling, a method of sealing a tape wrap jacket by means of thermal fusion.
- Heat Shock
- Test to determine stability of a material by sudden exposure to a high temperature for a short period of time.
- Helix
- Spiral winding.
- Henry
- Unit of inductance when the induced electromotive force of one volt is produced by the inducing current changing at the rate of one ampere per second.
- Hertz (Hz)
- A term replacing cycles-per second as the unit of measure for frequency.
- High Strength Alloy Conductor
- A conductor which shows a maximum 20% increase in resistance and a minimum of a 70% increase in breaking strength over the equivalent construction in pure copper while exhibiting a minimum elongation of 5% in 10 inches.
- High Voltage
- Generally considered to be a wire or cable with an operating voltage of over 600 volts.
- High Voltage Time Test
- An accelerated life test on a cable sample in which voltage is the factor increased.
- Hi-Pot
- A test designed to determine the highest potential that can be applied to conductor without breaking through the insulation.
- Hook-Up Wire
- Insulated wire used for low current, low voltage (under 1000V) applications internally within enclosed electronic equipment.
- Hot
- Connected, alive, energized. Said of a wire, terminal or any under grounded conductor.
- Hot Tin Dip
- A process of passing bare wire through a bath of molten tin to provide a coating.
- Hum
- A term used to describe the 60 cycle noise present in the sound of communication equipment.
- Hybrid Cable
- Multiconductor cable containing two or more types of components.
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- Ignition Cable
- Cable designed primarily for automotive ignition systems.
- Impact Strength
- Test for ascertaining the punishment a cable configuration can withstand without physical or electrical breakdown, by impacting with a given weight, dropped a given distance, in a controlled environment.
- Impedance
- The total opposition that a circuit offers to the flow of alternating current or any other varying current at a particular frequency. It is a combination of resistance R and reactance X, measured in ohms and designated by Z.
- Impregnate
- To fill the voids and interstices of a material with a compound. (This does not imply complete fill or complete coating of the surfaces by a hole-free film).
- Impulse
- A surge of unidirectional polarity.
- Impulse Strength
- The voltage breakdown of insulation under voltage surges on the order of microseconds in duration.
- Impulse Test
- An insulation test in which the voltage applied is an impulse voltage of specified wave shape.
- Inductance
- The property of a circuit or circuit element that opposes a change in current flow. Inductance thus causes current changes to lag behind voltage changes. Inductance is measured in henries.
- Inhibitor
- A corrosion inhibitor is a material which prevents or delays oxidation and galvanic action on a connector surface, or the interface of different conductors. Also, a chemical compound added to a mixture to restrain its chemical reaction until a d
- Inorganic
- Designating-or composed of-matter other than animal or vegetable, such as earthly or mineral matter.
- Insulated Wire
- A conductor of electricity covered with a no conducting material.
- Insulation
- Material having a high resistance to the flow of electric current to prevent leakage of current from a conductor.
- Insulation Resistance
- The ratio of the applied voltage to the total current between two electrodes in contact with a specified insulator.
- Insulator
- A material of such low electrical conductivity that the flow of current through it can usually be neglected.
- Interconnecting Wire
- The physical wiring between components (outside a module), between modules between units or between larger portions of a system or systems.
- Interstice
- A minute space between one thing and another, especially between things closely set or between the parts of a body.
- Ionization Voltage
- The minimum value of falling R.M.S. voltage which sustains electrical discharge within the vacuous or gal-filled spaces in the cable construction or insulation.
- IPCEA
- Insulated Power and Cable Engineers Association
- Iron-Constantan
- A combination of metals used in thermocouples, thermocouple wires and thermocouple lead wires. Constantan is an alloy of copper, nickel, manganese, and iron. The iron wire is positive, the constantan negative.
- Irradiation
- The exposure of a material to high energy emissions. In insulations for the purpose of favorably altering the molecular structure.
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- Jack
- A plug-in type terminal widely used in electronic apparatus for temporary connections. A connection is made to a jack simply by plugging into it a probe or plug attached to a flexible insulated wire or cable.
- Jacket
- A covering, sometimes taped or extruded over the insulation, core or shield of a cable.
- Jumper
- A short length of conductor used to make a connection between terminals or around a break in a circuit, or around an instrument. It is usually a temporary connection.
- Junction
- A point in a circuit where two or more wires are connected.
- Jute
- A natural fiber of plant base formed into rope-like strands. Used in cables for filling the interstices to give a round cross-section.
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- Kapton
- DuPont Company registered trademark for Polyimide film.
- Kilovolt
- 1000 volts.
- Kilovolt Ampere
- 1000 volts X amperes.
- Kilowatt
- A unit of power equal to one thousand watts.
- Kirchhoff's Laws
- (1) The algebraic sum of the currents which meet at any point is zero. (2) In any closed circuit the algebraic sum of the products of the current and the resistance in each conductor in the circuit is equal to the electromotive force in the circ
- KYNAR
- Registered trademark of Penwalt Corporation. Polyvinylidene fluoride (PVF2) is rated at 135C.
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- Lacing Cord or Twine
- Used for lacing and typing cable forms, hookup wires, cable ends, cable bundles, and wire harness assemblies. Available in various materials and impregnates.
- Lacing Tape
- Flexible flat fabric tape for tying harnesses and wire bundles, securing of sleeves and other items, and general lacing and typing applications. Available in various materials and impregnates.
- Lacquer Finish
- A finish applied over braided wire or cable for appearance and protection against fraying, wicking, moisture, absorption, abrasion, etc.
- Laminates
- Two or more layers, usually of different materials, bonded or laminated together.
- Lamp Cord
- Flexible stranded conductor cord, rubber or plastic insulated. Used for speaker cord, fans, lamps, etc.
- Lap Wrap
- Tape wrapped around an object in an overlapping condition.
- Lay
- The lay of any helical element of a cable is the axial length of a turn of the helix of that element. (Note: among the helical elements of a cable may be each strand in a concentric-lay cable, or each insulated conductor in a multi-conductor cable.)
- Lead
- A connecting wire, such as a test lead, battery lead, or conductor brought out from a coil or winding.
- LF
- Low frequency
- Limpness
- The ability of a cable to lay flat or conform to a bend.
- Line Cord
- A two-wire cord terminating in a two-prong plug at one end used to connect equipment or appliances to a power outlet.
- Line Voltage
- The voltage existing in a cable or circuit such as at a wall outlet or other terminals of a power line system. The line voltage is usually between 115 and 120 volts.
- Litz Wire
- Wire made from a number of fine, separately-insulated strands specially braided or woven together for reduced skin effect and hence lower resistance to high frequency currents for lower RF losses. The full name is Litzendraht Wire.
- Longitudinal Wrap
- Tape applied longitudinally with the axis of the core being covered as opposed to a helical or spiral tape wrapped core.
- Loss Factor
- The product of the power factor and the dielectric constant.
- Lossy Line
- A cable having a large attenuation per unit of length.
- Low Loss
- Term applied to a dielectric material or cable that has a small amount of power loss over long lengths making it suitable for transmission of radio frequency energy.
- Low Noise Cable
- Cable configuration specially constructed to eliminate spurious electrical disturbances caused by capacitance changes or self-generated noise.
- Low Tension
- Low voltage, as applied to ignition cable.
- Lug
- Termination, usually crimped or soldered to the conductor, with provision for screwing on to terminal.
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- Magnet Wire
- Insulated wire intended for use in windings on motor, transformer, and other coils for electromagnetic devices.
- Marker Tape
- A tape laid parallel to the conductors under the jacket in a cable, imprinted with manufacturer's name and the specification to which the cable is made.
- Marker Thread
- A colored thread laid parallel and adjacent to the strands of an insulated conductor which identifies the wire manufacturer and sometimes the specification under which the wire is constructed.
- MCM
- a thousand circular mils.
- Mega
- Prefix denoting one million.
- Melt Index
- Extrusion rate of a thermoplastic material through an orifice of specified diameter and length under specified conditions of time, temperature, and pressure.
- Melt Point
- The point at which a material melts.
- MeltRange
- The difference in degrees for F or C between the melt point of material and its flow point.
- Mfd
- microfarad, one millionth of a farad, the unit of capacitance.
- Micro
- Prefix denoting one-millionth.
- Microfarad
- One millionth of a farad.
- Microphone Cable
- A special shielded cable used to connect a microphone to an amplifier.
- Microwave
- A short electrical wave with a wave length usual of less than 30 cm.
- Microwave Frequency
- Frequency usually above 100 megahertz.
- Migration of Plasticizer
- Loss of plasticizer from an elastomeric plastic compound with subsequent absorption by an adjacent medium of lower plasticizer concentration.
- Mil
- 0.001" (1/1000 inch) one 1000th of an inch. A unit used in measuring diameter of wire or thickness of an insulation over a conductor.
- MIL
- military specifications for wire.
- Milli
- Prefix. denoting one thousandth.
- Mis-Match
- A termination having a different impedance than that for which a circuit or cable is designed.
- Modulus of Elasticity
- The ratio of stress to strain in a material that is elasticity deformed.
- Moisture Absorption
- Generally, the amount of moisture in percentage that an insulation will absorb under specified conditions.
- Moisture Resistance
- The ability of a material to resist absorbing moisture from the air or when immersed in water.
- Molded Plug
- A connector molded on either end of a cord or cable.
- Molecular Weight
- The weight of any molecule which is the sum of the weights of its constituent atoms.
- Multiconductor
- More than one conductor within a single cable complex.
- Multi-Conductor Cable
- A combination of two or more conductors cabled together and insulated from one another and from sheath or armor where used. (Note: special cables are referred to as 3-conductor cable, 7-conductor cable, 50-conductor cable, etc.)
- Multiple-Conductor Concentric Cable
- A cable composed of an insulated central conductor with one or more tubular stranded conductors laid over it concentrically and insulated from one another.
- Multiplex
- A method of putting two or more signals into a single channel.
- Mutual Capacitance
- Capacitance between two conductors when all other conductors including ground are connected together and then regarded as an ignored ground.
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- Nanosecond
- One billionth of a second.
- NEC
- National Electrical Code, which covers the use of wire and cable in many applications.
- NEMA
- National Electrical Manufacturers Association.
- Neoflon PFA
- Registered trademark of Daikin Industries, LTD. Perfluoroalkoxy (PFA). A 250© rated fluororpolymer that can be used for insulation and jacket applications.
- Neoflon
- Trademark of Daikin Industries, LTD.
- Neoflon ETFE
- Registered trademark of Daikin Industries, LTD. Polylenetetrafluoroethylene (ETFE), is a 150© rated fluoropolymer that can be used for insulation and jacket applications.
- Neoflon FEP
- Registered trademark of Daikin Industries, LTD. Fluoronatedethylenepropylene (FEP) is a 200© rated fluoropolymer that can be used for insulation and jacket applications.
- Nickel
- This metal offers combination of corrosion resistance, form ability, and tough physical properties. For these reasons, nickel is used for alloying purposes and in nickel-clad copper wire.
- Noise
- In a cable, any extraneous signals which tend to interfere with the signal normally present.
- Nylon
- the generic name for synthetic fiber-forming polyamides. Available in three forms for wires and cables: as a yarn for wire serving and braid; as an extrusion material (primarily for jackets); and a coating. For conductors of any but a small size, the electrical properties and hygroscopic properties of nylon limit its use to jacketing rather than primary insulation. Nylon extrusions are characterized by toughness and excellent oil resistance.
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- OD
- outside diameter.
- Ohm
- Unit of electrical resistance. Resistance of a circuit in which a potential difference of one volt produces a current of one ampere.
- Ohm's Law
- Current in terms of electromotive force E and resistance R: given by equation: I=E/R.
- Open Cell
- Foamed or cellular material with cells which are generally interconnected. Closed cells refers to cells which are not interconnected.
- Organic
- Designating or composed of matter originating in plant or animal life or composed of chemicals of hydrocarbon origin, either natural or synthetic.
- Over potential
- A voltage above the normal operating voltage of a device or circuit.
- Over voltage
- See Over potential.
- Overlap
- The amount the trailing edge laps over the leading edge of a spiral tape wrap.
- Ozone
- Form of oxygen produced by discharge of electricity into air.
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- Parallel Pair
- A duplex construction where the two insulated conductors are laid parallel and then covered overall with a braid or jacket. It is often referred to as "duplex cable".
- Percent Conductivity
- Conductivity of material expressed as a percentage of that of copper. Copper being 100%
- Percent Plating
- Quantity of plating on a conductor expressed as percentage by weight; thus, for the same percentage, as the conductor diameter increases, so does the thickness of the plating.
- Permittivity
- Preferred term for dielectric constant.
- Phase
- A particular stage or point of advancement in an electrical cycle. The fractional part of the period through which the time has advanced measured from some arbitrary point usually expressed in electrical degrees where 360 represents one cycle.
- Phase Shift
- Change in phase of a voltage or current after passing through a circuit or cable.
- Picks Per Inch
- The number of times the carriers in a braid cross over each other in the same direction along the longitudinal axis for each inch of length.
- Pitch Diameter
- Diameter of a circle passing through the center of the conductors in any layer of multiconductor cable.
- Plain Conductor
- A conductor consisting of one metal only.
- 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 about one another so the wire will not kink as it is twisted.
- Plastic
- High polymeric substances. Including both natural and synthetic products, but excluding the rubbers, that are capable of flowing under heat and pressure at one time or another.
- Plastic Deformation
- Change in dimensions of an object under load that is not recovered when the load is removed.
- Plasticizer
- Chemical agent added to plastics to make them softer and more flexible.
- Plating
- One method of applying a coating one metal over another.
- Polarity
- (1) An electrical condition determining the direction in which current tends to flow. (2) The quality of having two opposite charges.
- Polyamide
- A compound characterized by more than amide group. See nylon.
- Polyethylene
- A thermoplastic material composed of polymers of ethylene. A variety of types of polyethylene are used in wires and cables.
- Polyflon TFE
- Registered trademark of the Diakin Industries. Tetrafluoroethylene (TFE). A 260© rated Fluororpolymer that can be used for insulation or jacket.
- Polyimide
- Available for wire insulation in both film form and as a coating over an insulation or jacket.
- Polymer
- A compound formed by polymerization which results in the chemical union of monomers or the continued reaction between lower molecular weight polymers.
- Polymerize
- To unite chemically two or more monomers or polymers of the same king to form a molecule with higher molecular weight.
- Polypropylene
- A plastic made by the polymerization of high purity propylene gas in the presence of an organo metallic catalyst at relatively low pressures and temperatures. It is similar to polyethylene but stiffer.
- Polytetrafluoroethylene
- This is the most thermally stable and chemically resistant of all carbonaceous insulating compounds. It is unaffected by sunlight, moisture, and practically all chemicals. Temperature rang is -90( to + 250© and electrical properties are very con
- Polyurethane
- This material can be used as a jacketing material and offers good abrasion and is very flexible.
- Polyvinyl Chloride (PVC)
- A general thermoplastic material composed of polymers of vinyl chloride. PVC is widely used for primary wire insulation or jacketing.
- Polyvinylidene Fluoride
- This thermoplastic resin, a fluorocarbon, is characterized by good mechanical, electrical, and chemical properties. It is used for primary insulation and in jackets for multiconductor cables.
- Potential Voltage
- The work per unit charge required to bring any charge to the point at which the potential exists.
- Potting
- Sealing of a cable termination or other part with a liquid composition which hardens into an Elastomer or solid plastic material.
- Power
- The time rate at which work is done; equal to W/t where W is amount of work done in time t. Power will be obtained in watts if W is expressed in joules and t in seconds.
- Power Cables
- Cables of various sizes, construction, and insulation, single or multiconductor, designed to distribute primary power to various types of equipment.
- Power Factor
- (1) In an alternating current circuit, it is the number of watts indicated by a watt meter, divided by the apparent watts, the latter being the watts as measured by a voltmeter and a meter. (2) It is the multiplier used with the apparent watts to deter
- Primary Insulation
- A nonconductive material, usually the first layer over a current carrying conductor, whose prime function is to act as an electrical barrier for the applied potential.
- Propagation Delay
- Time delay between input and output of signal usually measured in nanoseconds per foot of cable.
- PTFE
- polytetrafluoroethylene.
- PVC
- See polyvinyl chloride.
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- Quad
- A four conductor cable.
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- Reactance
- Opposition offered to the flow of alternating current by inductance or capacitance of a component or circuit.
- Receptacle
- The half of the connector which is usually mounted on some support.
- Red Plague
- A powdery brown-red growth sometimes found on silver coated copper conductors and shield braids. It is fungus like in appearance and will appear in random spots along the length of a conductor or shield. It most often occurs at the point of crossover
- Reinforcement
- A material used to reinforce, strengthen, or give dimensional stability to another material such as the braid portion of a sheath constructed in layers.
- Resin
- An organic substance of natural or synthetic origin characterized by being polymeric in structure and predominantly amorphous. Most resins, though not all are of high molecular structure. Usually resins are more soluble in their lower molecular weight
- Resistance
- Property of a conductor that determines the current produced by a given difference of potential. The ohm is the practical unit of resistance.
- Resistive Conductor
- A conductor used primarily because it possesses the property of high electrical resistance.
- Resistivity
- Resistivity is the electrical resistance of a conductor of unit length and unit cross-sectional area (volume resistivity) or unit length and unit weight (mass resistivity). Resistivity units are based on the International Annealed Copper Standard (IACS) adopted by the International Electrotechnical Committee in 1913, which is 1/58 ohm-millimeter2/meter at 20°C for 100% conductivity. For volume resistivity this value is 0.017241 ohms-millimeter2/meter; for mass resistivity it is 0.15328 ohms-grams/meter2*. The latter terms mean that a copper wire 1 meter in length and weighing one gram would have a resistance of 0.15328O. * The expression ohm-gram/meter2 is a shortened expression for the unit (ohms/meter) (gram/meter), the term meter2 not denoting an area.
- Respool
- To transfer material from one package spool to another for various purposes, such as to verify lengths, inspect for defects, etc.
- RETMA
- Former Radio-Electronics-Television Manufacturers Association name changed to Electronics Industries Association (EIA).
- RF
- radio frequency.
- RF Connector
- Connector used for connecting or terminating coaxial cable.
- RG/U
- RG is the military designation for coaxial cable. The "U" stands for universal.
- Ribbon Cable
- Flat cable with conductors that have been individually insulated together. Structure is usually characterized by individual colors of insulation for each conductor, although a single color may be used for all conductors.
- RMS
- root-mean-square. When the term is applied to alternating voltage and current it means the effective value; that is, it produces the same heating effect as a direct current or voltage of the same magnitude. It is also a means of expressing a-c voltage
- Rockwell Hardness
- A test for hardness (resistance to indentation) of a material in which a hardened steel ball or diamond point is pressed the material under test.
- Roentgen
- The amount of radiation that will produce one electrostatic unit of ions per cubic centimeter volume.
- Rope Concentric
- A group of stranded conductors assembled in a concentric manner. The direction of lay of the outer rope members is usually left hand.
- Rope Unilay
- A group of stranded conductors assembled in a unilay manner. The direction of lay of the unilay rope is left hand.
- Rope-Lay Conductor or Cable
- A cable composed of a central core surrounded by one or more layers of helically laid groups of wires. (Note: This kind of cable differs from a concentric-lay conductor in that the main strands are themselves stranded. In the most common type o
- Round Conductor Flat Cable
- A cable made with parallel round conductor in the same plane.
- Rubber
- An Elastomer capable of rapid elastic recovery. Specifically, natural rubber, the standard of comparison for Elastomers.
- Rupture
- In breaking strength or tensile strength tests, the point at which a material physically comes apart as opposed to yield strength, elongation, etc.
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- SAE
- Society of Automotive Engineers.
- Secondary Insulation
- A nonconductive material whose prime functions are to protect the conductor against abrasion and provide a second electrical barrier. Placed over the primary insulation.
- Self-Extinguishing
- The characteristic of a material that extinguishes its own flame after the igniting flame is removed.
- Semi-Conducting Jacket
- A jacket having a sufficiently low resistance so that its outer surface can be kept at substantially ground potential by a grounded conductor in contact with it at frequent intervals.
- Serving
- A wrapping applied over the core of a cable or over a wire. Servings may be in the form of filaments, fibers, yarn, tape, etc.
- Sheath
- The protective covering applied to cables. Also referred to as Jacket.
- Shelf Life
- Length of time under specified conditions that a material retains its usability.
- Shield
- A metallic layer placed around an insulated conductor or group of conductors to prevent electrostatic or electromagnetic interference between the enclosed wires and external fields. This shield can be braided or served wires, oil wrap, foil backed tape,
- Shield Coverage
- When a metallic braid of tinned or bare copper is applied over the insulated conductors, the shielding effectiveness is in proportion to the amount of optical coverage, usually expressed in percentage.
- Shield Effectiveness
- The relative ability of a shield to screen out interference.
- Short Circuit
- An abnormal connection of relatively low resistance between two points on a circuit having a difference in potential.
- Shrinkable Tubing
- A tubing used to provide protection against mechanical damage for wires, cables, wire harnesses, splices, terminations, etc. They shrink to a predetermined size upon application of heat or solvent evaporation. Available in various plastic or Elastomers
- Shunt Wire
- A conductor joining two parts of an electric circuit to divert part of the current.
- Signal
- A current used to convey information, either digital, analog, audio, or video.
- Silicone
- Polymeric materials in which the recurring chemical group contains silicon and oxygen atoms as links in the main chain.
- Silver
- Silver is similar to gold in corrosion resistance. It costs less than other precious metals. It is very soft when fully annealed but work hardens during fabrication. It provides very good conductivity and solderability. It is widely used as plating or
- Sintering
- Forming articles from fusible powders at a temperature below melting point such as with PTFE.
- Skin Effect
- The phenomenon wherein the depth of penetration of electric currents into a conductor decreases as the frequency of the current increases.
- Skived Tape
- Tape shaved in a thin layer from a cylindrical block of material such as skived PTFE tape.
- Sleeving
- A braided, knitted, or woven tube.
- Solder
- A metallic alloy for uniting metals.
- Solid Conductor
- A conductor consisting of a single wire.
- Spark over
- A disruptive discharge between electrodes of a measuring gap, such as a sphere gap or oil testing gap.
- Spark Test
- A test performed on wire and cable to determine the amount of detrimental porosity (pin holes) or defects in the insulation.
- SPC
- silver plated copper.
- Specific Gravity
- The density (mass per unit volume) of any material divided by that of water at a standard temperature.
- Specific Inductive Capacity
- See dielectric constant.
- Splice
- A connection of two or more conductors or cables to provide good mechanical strength as well as good conductivity.
- Split Conductor Cable
- A cable in which each conductor is composed of two or more insulated conductors normally connected in parallel.
- Spurious Signals
- Undesired voltages in conductors caused by electrostatic magnetic or electrostatic coupling from other conductors or from external sources such as a transformer.
- Standing Wave Ratio
- A ratio of the maximum amplitude of a standing wave stated in current or voltage amplitudes.
- Storage Life
- The period of time during which a liquid resin or adhesive can be stored and remain suitable for use. Also called shelf life.
- Strand
- One of the wires, or groups of wires, of any stranded conductor.
- Stranded Conductor
- A conductor composed of a group of wires, or of any combination of groups of wires. (Note: The wires in a stranded conductor are usually twisted or braided together.)
- Strip
- To remove insulation from a wire.
- Submarine Cable
- Cable used underwater from one point to another for power or communication.
- Superconductors
- These are materials in which the resistance drops to almost zero. Superconductivity is exhibited by many of the metallic elements, their alloys, and intermetallic compounds.
- Surface Leakage
- The passage of current over the boundary surfaces of an insulator as distinguished from passage through its volume.
- Surface Resistivity
- The resistance of a material between two opposite sides of a unit square of its surface. Surface Resistivity may vary widely with the conditions of measurement.
- Surge
- A transient variation in the current and/or potential at a point in the circuit.
- Sweep Test
- Pertaining to cable, checking the frequency response by generating an RF voltage, the frequency of which is varied back and forth through a given frequency range at a rapid constant rate while the result on an oscilloscope.
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- Tank Test
- A term used to describe a voltage dielectric test where the specimen to be tested is submerged in a liquid (usually water) and a voltage potential applied between the conductor and the liquid is ground.
- Taped Insulation
- Insulation of helically wound tapes applied over a conductor or over an assembled group of insulated conductors.
- Tear Strength
- Force required to initiate or continue a tear in a material under specified conditions.
- Teflon FEP
- Registered trademark of the DuPont Company. Fluorinated ethylene propylene (FEP). A 200© rated Fluororpolymer that can be used for insulation and jacket applications.
- Teflon PFA
- Registered trademark of the DuPont Company. Perfluoroalkoxy (PFA). A 250© rated Fluororpolymer that can be used for insulation and jacket applications.
- Teflon TFE
- Registered trademark of the DuPont Company. Tetrafluoroethylene (TFE). A 260(rated Fluororpolymer that can be used for insulation and jacket applications.
- Tefzel
- Registered trademark of the DuPont Company. Ethylene tetrafluoroethylene (ETFE), is a 150( rated Fluororpolymer that can be used for insulation and jacket applications.
- Temperature Coefficient of Resistance
- This number is used to determine the change in resistance of a conductor between the temperature the conductor may see in use and 20 degrees Celsius. Most handbook tables and our wire card give the resistance in ohms per 1,000 ft at 20°C. Our customers often need to calculate the total resistance of a cable over the operating temperature range to properly size the conductors.
- Temperature Rating
- The maximum temperature at which the insulating material may be used in continuous operation without loss of its basic properties.
- Tensile Flex
- Hudson International trade mark for Phelps Dodge Alloy 135 high strength copper alloy.
- Tensile Strength
- The pulling stress required to break a given specimen.
- Tension Set
- The condition when a plastic material shows a permanent deformation caused by stress, after the stress is removed.
- Terminal
- A terminal is any fitting used for making a convenient electrical connection.
- Test Lead
- A flexible, insulated lead wire which usually has a test prod on one end. It is ordinarily used for making tests, connecting instruments to a circuit temporarily, or for making temporary electrical connections.
- TFE
- polytetrafluoroethylene.
- Thermal Conductivity
- Ability of a material to conduct heat.
- Thermal Endurance
- The time as a selected temperature for an insulating material or system of materials to deteriorate to some predetermined level of electrical, mechanical, or chemical performance under prescribed conditions of test.
- Thermal Expansion (Coefficient of)
- The fractional change in length (sometimes volume) of a material for a unit change in temperature.
- Thermal Resistance of a Cable
- The resistance offered by the insulation and other coverings to the flow of heat from the conductor or conductors to the outer surface.
- Thermal Shock
- The resulting characteristics when a material is subjected to rapid, and wide range changes in temperature in an effort to discover its ability to withstand heat and cold. In connectors, the effect can cause inserts and other insulation material
- Thermocouple
- A device for measuring temperature where two electrical conductors of dissimilar metals are joined at the point of heat application and a resulting voltage difference, directly proportional to the temperature, is developed across the free ends and is measured potentiometrically.
- Thermocouple Lead Wire
- An insulated pair of wires used from the couple a junction box or to the recording instrument.
- Thermoplastic
- A classification of resin that can be readily softened and resoftened by repeated heating.
- Thermosetting
- A classification of resin which cures by chemical reaction when heated and, when cured, cannot be resoftened by heating.
- Tinned Wire
- Copper wire that has been coated with a layer of tin or solder to simplify soldering.
- Tinsel Wire
- A low voltage, stranded wire where each strand is a very thin conductor ribbon spirally wrapped around a textile yarn. Insulation is generally a textile braid. Intended usage is for severe flexing.
- Tolerance
- A specified allowance for error from a standard or given dimension, weight, or property.
- Tracer Strip
- When more than one color coding strip is required, the first, or widest, strip is the base strip; the other, usually narrower strips, being termed tracer stripes.
- Tracer
- A means of identifying polarity. Two common types are ridges along the axis of the insulation perceptible to the touch and bands of contrasting color in braid or wind.
- Transfer Impedance
- For a fixed cable length, transfer impedance relates a current on one surface of a shield to the voltage drop generated by this current on the opposite surface of the shield. Transfer impedance is a measure of the shield effectiveness. Cables with low
- Transmission Line
- One or more insulated conductors arranged to transmit electrical energy signals from one location to another, or to transmitting electrical energy over long distances for power purposes.
- Transmission Loss
- A term used to denote a decrease or loss in power during the transmission of energy from one point to another. Usually expressed in decibels.
- Triaxial
- Refers to a three-conductor cable with one conductor in the center, a second circular conductor shield concentric with the first, and third circular conductor shield insulated from and concentric with the first and second, usually with insulation
- Triboelectric Noise
- Noise generated in a shielded cable due to variations in capacitance between the shield and conductor as the cable is flexed.
- Triplex Cable
- A cable composed of three insulated single conductors and often times one bare conductor, all twisted together. (Note: The assembled conductors may or may not have a common covering of binding or protecting material.)
- Tubing
- Extruded non-supported plastic or Elastomer materials.
- Twin Cable
- A pair of insulated conductors twisted and/or sheathed or held together mechanically and not identifiable from each other in a common covering.
- Twisted Pair
- A cable composed of two insulated conductors, twisted together without a common covering.
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- UHF
- Ultra High Frequency.
- UL
- Underwriters Laboratories, Inc.
- Ultra Violet Degradation
- Deterioration caused by long time exposure of a material to sunlight or other ultraviolet rays containing radiation.
- Unbalanced Line
- A transmission line in which voltages on the two conductors are unequal with respect to ground. A coaxial cable is an example.
- Unidirectional Concentric Standing
- A standing where each successive layer has a different lay length, thereby retaining a circular form without migration of strands from one layer to another.
- Unidirectional Stranding
- A term denoting that in a stranded conductor all layers have the same direction of lay.
- Unilay Strand
- A conductor constructed with a central core surrounded by more than one layer of helically-laid wires, with all layers having a common length and direction of lay.
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- Velocity of Propagation
- Applied to coaxial cables, velocity of propagation is the ratio of the dielectric constant of air to the square root of the dielectric constant of the insulator. It indicates the transmission speed of an electrical signal down a length of cable
- Vinyl Resin
- A synthetic resin formed by the polymerization of compounds containing the group CH2=CH - See Polyvinyl.
- Viscosity
- A measure of the resistance of a fluid to flow (usually through a specific orifice).
- Volt
- Unit of electromotive force. It is the difference of potential required to make a current of one ampere flow through a resistance on one ohm.
- Voltage
- The term most often used in place of electromotive force, potential, potential difference, or voltage drop, to designate electric pressure that exists between two points and is capable of producing a flow of current when a closed circuit is con
- Voltage Drop
- The amount of voltage loss from original input in a conductor of given size and length.
- Voltage Rating
- The highest voltage that may be continuously applied to a wire or cord in conformance with standards or specifications.
- Voltage Standing Wave Ration
- The ratio of the maximum effective voltage to the minimum effective voltage measured along the length of a mismatched radio frequency transmission line.
- Voltage Stress
- That stress found within a material when subjected to an electrical charge.
- Volume Resistivity (Specific Insulation Resistance)
- The electrical resistance between opposite faces of a 1-cm cube of insulating material, commonly expressed in ohm-centimeters.
- VSWR
- voltage standing wave ratio.
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- Wall Thickness
- A term used that expresses the thickness of a layer of applied insulation or jacket.
- Water Absorption
- Ratio of the weight of water absorbed by a material to the weight of the dry material.
- Water blocked Cable
- A cable constructed with no internal voids in order to allow no longitudinal water passage under a given pressure.
- Watt
- Unit of power or work done at a rate of one joule per second or rate or work represented by current of one ampere under a pressure of one volt (volt-ampere).
- Wave Length
- The distance, measured in the direction of propagation, of a repetitive electrical pulse or wave form between two successive points that are characterized by the same phase of vibration.
- Wicking
- The longitudinal flow of a liquid in a wire or cable construction due to capillary action.
- Wire Gauge
- A system of numerical designations of wire sizes. See American Wire Gauge (AWG).
- Wire
- A conductor of round, square or rectangular section. Either bare or insulated.
- Wrapping
- The method of insulating wire by serving insulating tapes around a conductor.
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- X
- Designation for reactance.
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- Yield Strength
- The lowest stress at which a material undergoes plastic deformation. Below his stress, the material is elastic; above it, viscous.
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- Z
- Designation for impedance.
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