A
Abrasion Resistance: A measure of the ability of a wire covering to resist damage by mechanical means. 

Adhesive Bonded: Cables bonded by adding an adhesive coating to the surface of the cable components, then joining and curing the adhesive to form a cable. See Bonded Cable. 

Adhesive Lined Tubing: Dual-wall tubing with an inner layer that melts and flows when heated, filling voids in the areas being covered, and forming a mechanical bond to the substrate. 

Alternative Current: An electrical current whose direction is reversed at regular intervals

ASTM: American Society for Testing and Materials, American Standard Testing Method.

ASTM D2671: Standard Test Methods for Heat-Shrinkable Tubing for Electrical use.

ASTM D638: Standard Test Method for Tensile Properties of Plastics.

AWG (American Wire Gauge): A method of specifying conductor size. Lower gauge numbers indicate larger conductor size.

B
Blocking: The sticking together of insulated wires; usually caused by heat.

Bonding Temperatures: Temperature above which adhesive melts and flows sufficiently to form an adhesive bond between substrates. 

Braid: A weave of metal fibers used as a shield covering for an insulated conductor or group of insulated conductors.

Bunch Stranding: A method of twisting individual strands to form a finished stranded conductor. 

Bus: A communal circuit over which data or power is conducted. 

Bushing: A device used to line an opening, which prevents abrasion to any wires and cables that are being passed through that opening. 

C
Cable: Two or more wires in a twisted or parallel configuration. 

Cable Clamp: A mechanical clamp attached to the cable side of a termination assembly to support the cable or wire bundle. 

Cable Clamp Adapter: A mechanical clamp attaches to the rear of the a termination assembly to allow the attachment of a cable clamp. 

Cable Sheath: The overall protective covering applied to cables. 

Capacitance: The property of an electrical conductor that permits the storage of energy as a result of electrical displacement. 

Capacity factor: The ration of the actual output of a generating facility over the period of time over the theoretical energy output of the generating facility operated as its rated capacity over the same time period. 

Carrier: A group of strands or ends used to form a finished band. 

Chemical Resistance: The ability of insulation to withstand the presence of materials that can deteriorate the insulation or can cause dielectric loss of insulating qualities. 

Circular Mil Area (CMA): A unit of area equal to the area of a circle whose diameter is 1 mil (0.001 inch). Used chiefly in specifying cross-sectional areas of conductors. 

Color Code: A means of identifying cable components using solid colors or stripes. Also the scheme that assigns a number 0 to 9 for each of 10 colors. 

Compound: An insulating or jacketing material made by formulating polymeric materials and additives. 

Compound Under Strands (CUS): A problem that occurs when loose stranding, or overheating during extrusion, allows compounds to get under individual strands or conductors.

Concentric Stranding: A method of stranding conductor. 

Conductivity: The capability of a material to carry electrical current. 

Conductor: The metallic strand or strands used to carry an electric current. 

Conductor Resistance: The resistance to flow of the electrical current along a conductor. 

Corrosion: Damage to the surface of a metal by chemical reaction. 

Contact: The element in a conductor that makes the actual electrical connection. 

Contact Resistance: Measurement of electrical resistance of mated contacts when assembled in a connector under typical service use. 

Continuity: A continuous path for the flow of current in an electrical circuit. 

Continuous Operating Temperature: Maximum temperature at which a component will maintain an acceptable lifetime performance. 

Colorant: Pigment additives used to introduce color to tubing. Both natural colored PVC and clear PVC can be colored. 

Compound: A chemical mixture of base resin and desired additives, which can be extruded into tubing. 

Concentricity: A comparison of the thinnest wall thickness to the thickest wall thickness. 

Core: The inner wall of dual wall, heat shrinkable tubing.

Cross-linking: The formation of three-dimensional covalent bonds between molecular chains in a polymer, thereby improving the mechanical and thermal properties. 

Cross-links: Covalent bonds linking one polymer chain to another. They have the characteristic property of thermosetting polymer materials. 

CSA (Canadian Standards Association): An agency that has developed standard specifications for products with particular emphasis on safety. 

Current: A movement or flow of electrons. 

D
Dielectric: A material that serves as an insulator. The amount of resistance to voltage in a given insulation. 

Direct Current: A form of power transmission and distribution in which electricity flows in a single unchanging direction.

Direct Current Resistance (DCR): The resistance offered by any circuit to the flow of direct current. 

Drain Wire: In a cable, an un-insulated conductor laid over the component in a foil-shield cable. 

E
Elastic Memory: The ability of a crosslinked polymer to be deformed to a predetermined shape, hold that shape for a period and return to its original shape. 

Elastometer: A material that exhibits very low or zero crystalinity and a high degree of flexibility. 

Elongation: The fractional increase in the length of a material stressed in tension. 

Encapsulant: Description related to the way dual-wall tubing products and precoated molded parts melt and flow when heated. 

Expanded ID (EID): The specified minimum (as supplied) internal diameter of tubing 

Expansion Ratio: An expression of how much larger the inside diameter of a tubing is before shrinking.

F
Flame Resistance: The ability of a material to not propagate flame once the heat source is removed.

Flame Retardant: An additive that is included in tubing compounds to improve resistance to burning. 

Flammability: The measure of a material's ability to support combustion. 

G
Gauge: A term used to denote the physical size of a wire. 

Ground: A connection, intentional or accidental, between an electrical circuit and the earth or some conduction body. 

Ground Connector: A conductor that provides a current return path from an electrical device to the ground. 

H
Hardness: An easily determined measurement of resistance to penetration that correlates well with mechanical strength and rigidity. Usually measured using Shore or Rockwell scales. 

Heat Distortion: Distortion of the flow or configuration of a material due to the application of heat. 

Heat Shrinkable: Tubing that is capable of being reduced in size when exposed to heat. 

Hookup wire and cable: Wiring used to connect various points in electrical assemblies. 

Hot-melt adhesive: An adhesive that becomes activated by heating. When heated, it melts, flows over the substrate surface and forms an adhesive bond. 

Hygroscopic: Capable of absorbing moisture from the air. 

I
ID (Internal Diameter): The inside of internal diameter of a tubing. 

Impulse Test: A high voltage test designed to locate pinholes in the insulation of a wire or cable by applying a voltage while the wire or cable is being drawn through an electrode. 

Inductance: One cause of reactance. 

Insulating Joint: A device, which mechanically couples and electrically insulates the sheath and armor of contiguous lengths of cable. 

Insulation Resistance: The electrical resistance between two conductors separated by an insulating material. 

Insulation, Thermal: A nonconductive material that prevents the passage of heat. 

Irradiation: In insulations, the exposure of the material to a high-energy emissions for the purpose of favorably altering the molecular structure via cross-linking. 

J
Jacket: An outer protective sheath over primary insulation, braids, shields, cable components, or over the cable itself. In fiber optics, a jacket is a covering over a single fiber, bundle of fibers or cable, which protects against the environment. 

L
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 covered. 

M
Modulus of Elasticity: The ratio of stress to strain in an elastic material. 

Moisture Absorption: The amount of moisture, in percentage, that a material will absorb under specified conditions. 

Moisture Resistance: The ability, of a material to resist absorbing moisture from the air, or when immersed in water. 

N
Neoprene: A synthetic rubber with good resistance to oil, chemical and flame. Also called polychloroprene.

Nominal: A description applied to a dimension representing the center of the range of tolerance or a value if no tolerance is applied.

O
Oil Aging: Cable aged in an accelerated manner by placement in an oil bath and heated to a pre­set temperature for a stated time. 

Operating Temperature: The maximum internal temperature at which a system, harness, or connector may operate in a continuous service, generally expressed as a time and temperature. 

Operating Temperature Range: The range between the maximum and the minimum internal temperature of insulation in a system, harness or connector in continuous service. The lower limit is determined by low temperature flex test. 

Oxygen Index: Percentage of oxygen necessary to support combustion in a gas mixture. 

Ozone: Reactive form of oxygen, typically found around electrical discharges and present in the atmosphere in small quantities. 

P
Plastic Deformation: A change in dimension that occurs when an object or material is under load, which is not recovered when the load is removed. 

Plasticizer: A chemical agent added to plastics to make them softer and more pliable. 

Polyester: Polyethylene terephthalate, used extensively as a moisture-resistant cable core wrap. 

Polyethylene: A thermoplastic material having excellent electrical properties. 

Polyhalocarbon: A general name for polymers containing halogen atoms. The halogens are fluorine, chlorine, bromine and iodine. 

Polymer: A compound consisting of long molecular chains formed from monomers occurring as repetitive “building blocks”. 

Polyolefin: A generic term for cross-linkable thermoset polymers. Polyolefin heat shrink tubing is usually made from polyethylene and its copolymers. 

Polypropylene: A thermoplastic that is similar to polyethylene, with the exception of being stiffer and having a higher softening point (temperature); also possesses excellent electrical properties. 

Porosity: Multiple voids in an insulation cross- section. 

Pull Tension: The maximum pulling force that can be safely applied to a cable without damage.

Polyvinyl Chloride (PVC): A general-purpose thermoplastic widely used for wire and cable insulations and jackets. 

Primary Insulation: The inner member of a dual-wall wire insulation. The insulation applied directly on the conductor. 

R
Radiation Crosslinking: The act of crosslinking a material with ionizing radiation. 

Rated Temperature: The maximum temperature at which a component can operate for extended periods with acceptable changes in its basic properties. 

Rated Voltage: The maximum voltage at which an electric component can operate for extended periods without undue degradation. 

Recovery (Heat Shrinkable Components): Heat activation of the elastic memory effect to cause expanded tubing to return to its originally extruded size. 

Recovered ID: The internal diameter of heat shrinkable tubing after being allowed to recover fully. 

Recovery Temperature: The midpoint of the recovery versus temperature curve of heat shrinkable tubing. 

Resin: The base material in a plastic compound. 

Resistance: A measure of the difficulty in moving electrical current through a conductor or insulation when a voltage is applied. 

S
Secondary Insulation: A nonconductive material that protects a cable’s conductor against abrasion and provides a second electrical barrier. 

Selenium Cure: Process used to cure neoprene and rubber-jacketed wires and cables. 

Self-Extinguishing: Characteristic of a material whose flame is extinguished after the igniting flame source is removed. 

Semi-Rigid: A cable containing a flexible inner core and relatively inflexible sheathing. 

Semi-Solid: An insulation cross-section having a partially open space between the conductor and the insulation perimeter. 

Serve: A filament or group of filaments, such as fibers or wires, which are wound around a central core. 

Serving: A wrapping applied over a wire or the core of a cable. 

Sheath: See Cable Sheath. 

Shore Hardness: A series of scales used to indicate hardness. The Shore A scale is most commonly used to measure the hardness of plastic tubing. Within a given scale, a higher number indicates a harder material. 

Shield: In cables, a metallic layer placed around a cable’s conductor to prevent electrostatic or electromagnetic interference between the enclosed wires or external fields.

Shield Coverage: Amount of outer cable covered by the shielding material. 

Shrink Ratio: The nominal ratio of expanded diameter to recovered diameter of heat shrinkable tubing. 

Silicone: A material made from silicon and oxygen, which can be found either in thermosetting elastomer form, which is noted for its high heat resistance, or as a liquid. 

Silicone Treating: A silicone liquid treatment applied to insulated conductors to allow for easy jacket stripping. 

Sleeve: The insulated or metallic or metallic covering over the barrel of a terminal. 

Specific Gravity: The ratio of the density (mass per unit volume) of a material to the density of water. 

Splice: A joining of conductors, generally from separate sheaths. 

Splice Closure: A device used to protect a cable or wire splice. 

Strain Relief: The reduction of the stress or strain on an object that is obtained through the use of an outer covering of tubing to provide additional stiffness. 

T
Tear Strength: The force required to initiate or continue a tear in a material under specified conditions. 

Temperature Rating: The maximum temperature at which an insulating material may be used in continuous operation without loss of its basic properties. 

Tensile Strength: The ratio of the amount of axially applied force required to break or rupture a piece of tubing to the cross-sectional area of the tubing. It is expressed in units of force/area, such as pounds per square inch (psi). 

Thermal Aging: Exposure to a thermal condition or programmed series of conditions for preset periods of time. 

Thermal Rating: The effect of heat of cold applied at such a rate that non-uniform thermal expansion or contraction occurs within a given material or combination of materials. 

Thermoplastic: A polymer that can be repeatedly melted and solidified with only minimal degradation of the properties each cycle. Common examples are polyvinyl chloride and polyethylene. 

Thermoset: A polymer, such as polyolefin, in which irreversible chemical “curing” or “set” takes place (the molecule chains are cross-linked in three dimensions. 

U
UL (Underwriters Laboratories): A nonprofit independent testing organization that operates a listing service for electronic materials and equipment. 

UL 224: An Underwriters Laboratories standard that gives requirements for heat-shrink tubing, cross-linked tubing and insulating tubing made of extruded thermosetting, elastomeric, or thermoplastic polymers. 

Ultraviolet Degradation: The degradation caused by long-term exposure of tubing to sunlight or other ultraviolet rays. 

Ultraviolet (UV) Stabilizer: An additive to tubing compounds that protects against loss of strength or discoloration when it is exposed to the outdoors. 

Urethane: See Polyurethane. 

W
Wall Thickness: The thickness of the applied insulation or jacket. 

Water Absorption: A test to determine the water absorbed by a material after a given immersion period.