GLOSSARY OF ELECTRICAL TERMS

Summit Electric Supply has collected hundreds of definitions to help you find the meaning of words, acronyms and regulations you may run into in the electrical industry.

Term

Definition

A

Asbestos-insulated, no braid, for dry locations only. In raceways, only for leads to or within apparatus. Limited to 300V, 200°C.

A/D

Analog to digital signal conversion

AA

Asbestos-insulated, asbestos or glass braid. Dry locations only. Open wiring. In raceways, only for leads to or within apparatus. Limited to 300V, 200°C.

AAA

Aluminum Association of America

AAAC

All aluminum alloy conductor, usually used to refer to 6201 aluminum alloy.

AAC

Aluminum Alloy Conductors

AAR

American Association of Rail Roads

AASC

Aluminum Alloy Stranded Conductors

AB

High-voltage butyl cable.

ABC

Armored bushed cable. BX-armored building wire with polyvinyl chloride insulation, 600V

ABP

Butyl-polyethylene high voltage cable, 75°C.

Abrasion Resistance

Ability of material or cable to resist surface wear.

ABS

Acrylonitrile butadiene styrene

Absolute Pressure (PSIA)

Pressure measured relative to a vacuum (absolute zero).

Absorption

The property of materials such as clothing, drapes, carpeting on racks, acoustic ceilings, etc., which causes them to soak up or deaden sound.

AC

Branch circuit and feeder cables with flexible metal tape armor.

AC adapter

A device intended to convert line voltage alternating current to low voltage AC or DC current.

AC Input Mode

An I/O module that converts various AC signals originating at user devices to the appropriate logic level signal for use within the processor of a programmable controller.

AC Output Module

An I/O module that converts the logic level signal of the processor to a usable output signal to control a user AC device.

ACA

Synthetic tapes, felted asbestos, glazed cotton or glass braid, 1000V, 90°C.

ACAR

Aluminum Conductor Alloy Reinforced

Accelerated Aging

A test performed on material or cable meant to duplicate long time environmental conditions in a relatively short space of time.

Accelerator

A chemical additive which hastens a chemical reaction under specific conditions.

Accent Lighting

directional lighting to emphasize a particular object or dawa attention to a part of the field of view.

Accuracy

The total of all deviations from a specified straight line including the sum of nonlinearity, repeatability, and hysteresis expressed as a percent of full scale output.

B

Same as AVC. Motor lead wire.

B+S

Brown and Sharpe wire gauge-same as AWG.

Backbone Wiring

The physical interconnections between the entrance facility and various floors or telecommunications closets.

Baffle

A single opaque or translucent element to sheild a source from direct view at certain angles or to absorb unwanted light.

Baking

Heating to a low termperature in order to remove gasses. Curing or hardening surface coatings such as paints.

Balance Circuit

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.

Balance Point

The tempearture at which the heat pump can no longer provide all the heating requirements of home. At this point a backup heater automatically comes on to assist the compressor in maintaining the temperature set on the thermostat.

Ballast

Devices that by means of inductance, capacitance or resistance, singly or in combination, limit the lamp current of fluorescent or mercury lamps, to the required value for proper operation, and also, where necessary, provide the required starting voltage and current.

Ballast Efficacy Factor

Measure used to compare various lighting systems.

Ballast Factor

Measure of light output from lamp operated by commercial ballast, as compared to a reference ballast.

Ballast Hum

Sound made by operating core & coil ballast, generated by the electromagnetic field that transforms the current for discharge lamp use. High frequency solid state ballasts may also make a sound, but at a significantly lower level which is inaudible - except in the case of some solid state ballasts that use non-electronic power factor correction which is relatively "noisy."

Ballast Losses

Power which is supplied to the ballast but is not converted into light energy.

Ballast noise rating

Ballast noise ratings are designated by letters starting with letter A (the quietest) through F. The rating A is best for applications where the surrounding and competitive noise level may be at a minimum.

Ballast Performance Factors

Measurements that allow the comparison of various ballasts in terms of their power efficiency and ability to produce light. Include power factor, ballast factor and ballast efficacy factor.

Band

The frequency spectrum between two defined limits, especially those delimiting a channel.

Band Marking

A continuous circumferential band applied to a conductor at regular intervals for indentification.

Bandwidth

A measure of the amount of information which can pass through a channel, expressed in Hertz (Hz). Higher bandwidth means greater capacity to carry data.

Banked

This term is used when two or more single phase transformers are connected or banked together to supply power to a three phase load. The three single phase transformers banked together will produce a KVA capacity of three times the nameplate rating of each of the single phase transformers. Example, three 5 KVA single phase transformers connected together for a three phase load will have a KVA capacity of 15 KVA.

Bar

A piece of material thicker than a sheet, long in proportion to its width or thickness and whose width-thickness ratio is much smaller than sheet or plate, as low as unity or squares and rounds. Bars are generally smaller in cross section than billets or other forms of forging stock.

Bar Coil

A bar coil is constructed of a ferrite bar and is wrapped with copper wire. This device is used to reduce RFI generated by a dimmer or other electronic switching devices.

Base Speed of an Adjustable-Speed Motor

The speed of a motor obtained with full field under full load with no resistor in the armature circuit.

Baseband

With reference to LAN, the system whereby digitally encoded information is directly connected to the transmission medium without being modulated. Compare with broadband.

Battery

Device that changes chemical energy into electrical energy.

Baud

Strictly speaking, the number of signal-level transitions per second in digital data. For some common coding schemes, this equals bits per second, but this is not true for more complex coding where it is often misused. Thelecommunication specialists prefer bits per second, which is less ambiguous.

Bayonet

A lampholder for low-voltage incandescent lamps having an unthreaded metal shell with two diametrically opposite keyways that cooperate with similarly located projections on a mating lamp bulb. Pushing down on the bulb and turning it clockwise in the socket locks the bulb in place.

BDC

Plastic busdrop cable

Beam Lumens

The lumens contained within the beam spread of a floodlight.

Beam Spread

In any plane, the angel between the two directions in which the candlepower is equal to a stated percent (usually 10 percent) of the maximum candlepower in the beam.

Bearing Plate

Steel plate placed under one end of a beam or truss for load distribution.

Bearing Wall

Wall supporting a load other than its own weight.

Bellows

Type of pressure switch actuator with a fixed effective area for a constant differential over the entire range of the pressure switch.

Bench Mark

Point of reference from which measurements are made.

Bend Radius

The minimum radius to which a cable or fiber can be bent before excessive signal attenuation occurs.

Bending Equipment

Manual, motorized, hydraulic or heat-driven to bend all varieties and diameters of raceway at suitable angles.

Best Fit Straight Line (BSFL)

The best straight line chosen such that the transducer response curve contains points of equal maximum deviations.

BICSI

(Building Industry Consulting Service International) An industry association dedicated to the design and installation of communication wiring.

BIL

Basic Insulation Level is a measure of the ability of the insulation system to whithstand very high voltage surges. For example, a 600 volt class transformer has a 10KV BIL rating.

Billet

A solid semifinished round or square product that has been hot worked by forging, rolling or extrusion.

Bimetallic

A strip of two metals having different coefficients of expansion, bonded together usally in the form of a spiral or strip. Movement of the bonded metals caused by a tempeature change can initiate a change in a device or circuit.

Binder

Usually a spirally served tape or thread used for holding assembled cable components in place awaiting further manufacturing operations.

Bi-Pin Medium

A fluorescent lampholder having two contacts, used in pairs, with type T-8 tubular fluorescent lamps that are approximately 1" in diameter, having two contacts at each end.

Bi-Pin Miniature

Similar to medium Bi-Pin lampholdeer except for use with Type T-5 tubular fluorescent lamps that are 5/8" in diameter

Blackout

A condition where power fails altogether, causing the immediate stoppage of any device that functions on electrical current.

Blower

A fan used to force air under pressure.

Bobbins

Metal sools used for taking up drawn wire and subsequently used for payout packages in cabling and stranding equipment.

Bolt-In Fuse

A fuse which is intended to be bolted directly to bus bars, contact pads or fuse blocks.

Bond Strength

Amount of adhesion between surfaces, e.g. in cemented ribbon cable.

Bonding

The permanent adhesion of metallic parts forming an electrically conductive path.

Bonding Jumper

A reliable conductor used to ensure the required electrical conductivity between metal parts required to be electrically connected.

Booster

A generator inserted in series in a circuit to add or subtract from the circuit voltage.

Box

A wiring device that is used to contain wire terminations where they connect to other wires, switches, or outlets.

Box Mounted Dimmers/Fan Speed Control

Any dimmer or fan speed control that mounts in or on a NEMA standard switch box.

Braid

A fibrous or metallic group of filaments interwoven in cylindral form to form a covering over one or more wires.

Braid Angle

A term used in the determination of the braid configuration relating to the angle of the braided filaments or fibres in relationship to the axis of the cable core being braided.

Braid Carrier

A spool or bobbin on a braiding machine holding one group of strands or filaments consisting of a specified number of ends. The carrier revolves during the braiding operation.

Braid Ends

In a braid the given number of strands used to make up one carrier. The strands are wound side by side on the carrier bobbin and lay parallel in the finished braid.

Braider

A machine used to apply a woven fiberous or metallic braid over a cable.

Brake Wire

Wire used in mobile-home, travel and truck trailers to supply current to the electrical breaking system.

Branch Circuit

A circuit that supplies a number of outlets for lights, applicances, equipment etc.

Break Magnetic

A friction brake which is controlled by electromagnetic means.

Break of a Circuit-Opening Device

The minimum distance between the stationary and movable contacts when these contacts are in the open position.

Breakdown Voltage

The voltage at which the insulation between two conductors is destroyed.

Breakout

A term used to define a wire or group of wires in a multi-conductor configuration which terminate somewhere other than at the end of the configuration.

British Thermal Unit

(BTU)a heat unit equal to the amount of heat required to raise one pound of water one degree fahrenheit.

Brownout

Utility supply voltage dips below its nominal supply voltage.

BSC

Bare soft copper - uncoated annealed copper.

Building Wire

Wire used for light power in permanent installations utilizing 600 volts or less. Usually in an enclosure and which will not be exposed to outdoor environments.

Bulb Sing (Filament Hum)

The audible noise which can come from an incandescent lamp controlled by a dimmer.

Bunch Wrap

Any number of conductor strands twisted together in one direction with the same lay length.

Bundle

More than one cable held in a single Grip.

Burst Pressure

The maximum pressure that can be applied to a transducer wihtout rupture of either the sensing element or the transducer case.

Bus

A set of power supply leads or a conductor providing for multiple connections.

Bus Bar

A heavy solid conductor at the main power source to which branch circuits are connected.

Bus Interface Unit

(BIU)The data circuit terminating equipment which provides access to a LAN. It may also provide packet assembly/dissassembly functions.

Butt Wrap

A spirally wrapped tape over a cable core where the trailing edge of one wrap just meets the leading edge of the preceding wrap with neither overlap nor spacing.

BW

Braided wire armor. Basket weave.

BX

Armored building wire, 600V.

Bypass

A circuit that carries telephone signals from a subscriber to another point without the use of local telephone company circuits.

C

Lamp cord, two or more conductors twisted together. Rubber insulation, cotton braid. For pendant or portable use in dry places. No overall covering. 300V or 600V, 60°C

Cable

An insulated conductor or twisted group of conductors used for the transmission of electrical energy.

Cable Cutter

Specially deisigned tool for easy cutting of cable

Cable Preparation Took

Cuts, slits and removes insulation from a variety of cable.

Cable Protector

A fuse with characteristics designed to protect cables against fault damage. Cable protectors have unique mounting and crimping terminals.

Cable Roller

Device installed on cable tray or cable ladder to help pull cables.

Cable Tie

Means of bundling wire and cable and or means of support.

Cabling

The twisting together of two or more insulated conductors to form an element.

CAC

Flexible copper, synthetic tapes, felted asbestos and lacquered braid. 1000V, 125°C

CAD/CAM

Computer Aided Design, Computer Aided Manufacturing.

Cadmium Plating

An Electroplated coating of cadmium on a steel surface which resists atmospheric corrosion. Applications include, nuts, bolts, screws and many hardware items in addtion to enclosures.

Calibration

The process of setting a measurement instrument by use of standards.

Campus

A comples of buildings which operate as one continuous facility - e.g., multi-building corporate headquarters, university, military base.

Candela, cd

(formerly candle) The unit of luminous intesity.

Candelabra

A small screw-base threaded lampholder accepting a bulb approximately 1/2" in diameter commonly used in night lights, indicator lights and Christmas tree bulbs.

Candlepower distribution curve

A curve, generally polar, representing the variation of lumious intensity of a lamp or luminaire in a plane through the light center.

Candlepower, cp

Term which expresses intensity of a beam of light.

Capacitance

The ratio of the electrostatic charge or a conductor to the potential difference between the conductors required to maintain the charge.

Capacitive Coupling

Electrical interaction between two conductors required to maintain that charge.

Capacitor or Condensor

An electrical device that causes the current to lead the voltage, opposite in effect to inductive reactance. It is used to neutralize the objectional effect of lagging (inductive reactance), which overloads the power source. It also acts as a low resisrance path to ground for currents of radio frequency, thus effectively reducing radio disturbance.

Capillary Action

The phenomenon of liquid rising in a small interstice due to surface tension.

Capitance Detector

A device with single or multiple probes that with an object coming within proximity of the detector, will cause a change in probe capacitance. This change in prope capacitance will allow the detector to turn the load on or off.

Carbonitriding

A case hardening process in which a suitable ferrous material is heated above the lower transformation temperature in a gaseous atmosphere of such composition as to cause simultaneous absorption of carbon and nitrogen by the surface and by diffusion, create a concentration gradient. The process is completed by cooling at a rate that produces the desired properties in the workpiece.

Carrier

A continous frequency capable of being modulated by an information carrying signal.

Cartridge Fuse

A fuse consisting of a current responsive element inside a fuse tube with terminals on both ends.

Cast Tape

A material which is formed directly into a tape by means of flowing or "casting" a solution or dispersion of the film-forming material onto a suitable carrier, then removing the solvent - as opposed to skiving or slicing a block of material into a tape form.

Cathode Ray Tube (CRT)

An electronic device that can be used to display graphic images and which is commonly used in data processing.

CATV

Community Antenna Television, known as cable television.

CB

Rubber-insulated brewery cord, with weather-proof braid on each conductor. Twisted, no overall covering.

CBM

Certified Ballast Manufactures'Association

CBO

Neoprene-insulated brewery cord for use in damp locations.

CENELEC

An acronym for the European Committee for Electromechanical Standardization. A European standard that allows retrofitting of devices that are of Cenelec standard. They have same dimensions, mounting capablities, and sensing ranges.

Ceramic

Pertaining to a product made from inorganic, nonmetallic materials fused or fired at high temperatures; used as an insulation in cables when extremely high temperatures are to be encountered.

Certificate of Compliance (C of C)

A cerrificate which is normally generated by a quality control department which shows that the product being shipped meets Customer's specifications.

CF

Fixture wire, heat resistant, with flame-retardant, moisture-resistant impregnated cotton insulation. With or without plain or fancy cotton or rayon braid. 300V, 90°C

CFC

Two or three CF type wire twisted together without overall covering. Color coded. 300V, 90°C

CFPD

Two or three CF type wires twisted together with overall braid. Color coded. 300V, 90°C

CFPO

Two CF type wires laid parallel with overall braid. Color coded. 300V, 90°C

Channel

The complete communications path between telecommunications closet equipment and workstation equipment which includes cross-connects and patch.

Characteristic Impedence

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 everypoint along a transmission line on which there are no standing waves.

Choke

A device used to filter RFI noise generated by dimmers or other electronic switching devices.

Chromaticity

The aspect of color that includes consideration of its dominant wavelength and purity

Circline

A four contact, double-ended lampholder for use with tubular, circular, fluorescent lamps.

Circuit (Electric)

A conductive path over which an eletrical charge can flow.

Circuit Breaker

A device designed to open and close a circuit by non-automatic means and to open the circuit automatically on a predetermined overcurrent without injury to itself when properly applied within its rating.

Circuit Interrupter

A circuit interrupteer is a non automatic manually operated device designed to open, under abnormal conditions, a current-carrying circuit without injury to itself.

Circular Mil

A measurement used in determining the area of a wire. The area of a circle one one thousandth inches in diameter.

Cladding

A method of applying a layer of metal over another metal, whereby, the junction of the two metals is continuously welded

Class CC Fuse

A small current-limiting rejection type fuse for control circuits. Rated 0-30 amperes, 600 volts and 200,000 amperes interrupting rating.

Class G Fuse

A small current-limiting fuse which come in four sizes 0-15A, 20A, 25-30A and 35-60A which are non-interchangeable. Rated 480 volts with a 100,000 ampere interrupting rating.

Class H Fuse

Any 250 or 600 volt "standard" dimension fuse, either renewable or non-renewable which has a 10,000 ampere interrupting rating.

Class J Fuse

A 600 volt non-interchangeable current-limiting fuse of small, unique dimensions. Available in ratings 0-600 amperes with a 200,000 ampere interrupting rating.

Class K Fuse

A 250 or 600 volt standard dimension fuse (no rejection feature) with an interrupting rating of 50,000 or 100,000 amperes, meeting specific lp and 1²t limits. Available in ratings 0-600 amperes.

Class L Fuse

A 600 volt bolt-in, current limiting fuse of small, unique dimensions. Available in rating 0-600 amperes with a 200,000 ampere interrupting rating.

Class R Fuse

A 250 or 600 volt standard dimensions fuse with a 200,000 ampere interrupting rating and a rejection feature on one terminal. They are current-limiting fuses rated 0-600 amperes.

Class T Fuse

A small, unique dimension current limiting fuse, non-interchangeable with any other fuse. Available in 300 volt and 600 volt sizes, rate 0-1200 amperes, with a 200,000 ampere interrupting rating.

Clearing Time

The total time between the beginning of the overcurrent and the final opening of the circuit at rated voltage by an overcurrent protective device. Clearing time is the total of the melting time and the arcing time.

Clock Hanger

A single receptacle generally recessed behind a special cover plate having a hook or other means of supporting a wall-hung clock.

Closed Circuit

Electrical circuit which provides path for flow of current.

Closed Circuit Transition

As applied to reduced voltage controllers, is a method starting by which the power to the motor is not interrupted during normal starting sequence. Open circuit transition is a method of starting in which the power to the motor is interrupted during normal starting sequence.

Closed Loop Control

Controller automatically compensates for variables, e.g. product temperature ambient temperature, conveyor speed, etc.

Closing a Circuit

Placing the circuit in operation.

CMA

Circular Mil Area.

CO/ALR

A marking designation used on certain devices to indicate their suitability for connection to either aluminum or copper conductors.

Coaxial

A cable configuration having two cylindral conductors with coincidental axis, such as, conductor with a tubular shield surrounding the conductor and insulated from it.

Coefficient of Beam Utilization

(CBU)The percentage of light from a floodlight which reaches the seeing task relative to beam lumens.

Coefficient of Performance

(COP)The ratio of the rate of heat removal to the rate of energy input, inconsistent units, for a complete refrigerating plant under designated operating conditions.

Coefficient of Utilization, CU

The ratio of the luminous flux (lumens) from a luminaire calculated as received on the work plane to the luminous flux emitted by the luminaire's lamps alone.

Coil

Windings of copper or aluminum wire surrounded by a core in ballast.

Coilmate

Function of lens and reflector in a photoelectric device, concentrating the light beams from the light source.

Cold Bend

Generally refers to a test to determine cable or wire characteristics at low temperatures.

Cold Flow

Permanent deformation of the insulation due to mechanical forces without the aid of heat softening of the insulating material.

Cold Joint

A soldered joint made with insufficient heat.

Cold Work

The hardening and embrittlement of a metal by repeated flexing action.

Color Code

A color system for circuit identification by use of solid colors, tracers, braids, suface printing, etc.

Color Discrimination

The perception of differences between two or more colors.

Color Mark Detector

A sensor designed to differenciate between two different colored marks, or between a color mark and the background color it appears on. The contrast between the two marks, not the true color of the mark, is used for this detection. The color mark detector is available with either Red or Green LED emitter for this purpose.

Color Rendering

A general expression for the effect of a light source on the color appearance of objects in conscious or subconscious comparison with their color appearance under a reference light source.

Combination Starter

A magnetic starter having a manually operated disconnecting means built into the same enclosure with the magnetic contractor or starter.

Combination Wall Plates

A multiple gang wall plate with different openings in each gang for different devices.

Common Ground Connection

Location where two or more continuous grounded wires terminate.

Common Mode

Noise, caused by a difference in "ground potential." By grounding at either end rather then both ends (usually grounded at source) one can reduce this interference.

Commutator

Device used on electric motors or generators to maintain a unidirectional current.

Compact Conductor

A concentric stranded conductor which after stranding and on subsequent layers in a multiple layered cable, is passed through a closing die or roller die to reduce the diameter approximately 10% thus eliminating the normal interstices in the cable.

Compact Round Conductor (ASTM B-496)

A concentric stranded conductor with the layers of indivdual wires all laid in the same direction and rolled or die compacted by layer to a predeteremined size. This results in an extremely smooth conductor at the same time preserving the flexiblility of a stranded conductor. Advantages are minimum overall diameter for a given conductor area and freedom from "bird caging" of strand under bending, and the practical elimination of space between strands. Used in some high voltage power cables.

Compatiblility

The ability of various specified units to replace one another, with little or no reduction in capablility. The ability of units to be interconnected and used without modification.

Compensated Temperature Range

The range of ambient temperatures within which the transducer will perform according to its output specifications.

Compensator

a manually operated reduced voltage starter.

Complementary Outputs

Sensors with both N.O. and N.C. outputs which change state simultaneously.

Component

The smallest element of a circuit (i.e. resistor, capacitor, transistor or integrated circuit package.)

Composite Conductor

A composite conductor consists of two or more strands of different metals, such as aluminum and steel, or copper and steel. i.e.: ACSR, ACAR, AWAc.

Compound

A term used to designate an insulating and jacketing material made by mixing two or more ingredients. To compound: the mixing together of two or more different materials to make one material.

Compressed Conductor

A concentric stranded conductor which after stranding, or on subsequent layers of a multiple layered conductor, is passed through a die to reduce the overall diameter approximately 3%.

Concentric Neutral

A number of wire concentrically stranded about a cable for use as a neutral.

Concentric Stranding

A group of uninsulated wires twisted so as to contain a center core with one or more distinct layers of spirally wrapped, uninsulated wires laid overall to form a single conductor. When more than one layer is present each layer must have a different lay length.

Concentricity

In a wire or cable, the measurement of the location of the center with respect to the geometric center of the circular insulation.

Concentric-Lay-Cable

A cencentric-lay conductor or a multiple-conductor cable composed of a central core surrounded by one or more layers of helically laid conductors.

Conductance

A measure of the ability of a conductor configuration to conduct an electrical charge. Conductance is a ratio of the current flow to the potential difference causing the current flow.

Conducting Parts

Those parts designed to carry current or which are conductively connected therewith.

Conductivity

A term used in describing the capability of a material to carry an electrical charge. Usually expressed as a percentage of copper conductivity - copper being one hundred (100%)percent. Conductivity is expressed for a standard configuration of conductor.

Conductor

Any material capable of carrying an electrical charge easily.

Conductor Losses

Losses caused by the resistance of the transformer winding and usually measured at 25,50,75 and 100 percent of load.

Conduit

An enclosure for conductors. For underground wiring there are numerous kinds of conduit: fiber, asbestos cement, metallic, soapstone, rigid polyvinyl chloride (PVC), fiberglass epoxy, etc.

Connected Load

The combined continuous rating of all the equipment connected to the system or part of the system under consideration.

Connecting Block

A plastic block with metal wiring clips used to establish an electrical connection.

Connector

A mechanism used to unite two pieces of cable or cable to an apparatus, both physically and electrically.

Connector Grip

A Strain Relief Grip for specific Customers usually attached to a connector retaining nut.

Constant Current Source

Source which provides constant current to the output of a switching transistor, and allows the voltage at the output to vary from zero up to the supply voltage.

Constant Current Source

Source which provides constant current to the output of a switching transistor, and allows the voltage at the output to vary from zero up to the supply voltage.

Constant-Speed Motor

A motor whose speed is either constant or varies little, such as synchronous motors, induction motors with low slip and ordinary direct-current shunt motors.

Contact

The surface common to two conducting parts, united by pressure, for the purpose of carrying current.

Contactor

A device for repeatedly establishing or interrupting an electrical circuit under normal conditions. It is usually magnetically operated.

Continuity Check

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 Current

Steady-state current. AC or DC.

Continuous Rating

The maximum constant load that can be carried continuously without exceeding established temperature rise limitations under prescribed conditions.

Contrahelical

A term meaning the application of two or more layers of spirally twisted, served, or wrapped materials where each successive layer is wrapped in the opposite direction to the preceding layer.

Control Cable

A multiconductor cable made for operation in control or signal circuits, usually flexible, relatively small in size, and with relatively small current ratings.

Control Switch

A manually operated switch for controlling power operated switches and circuit breakers.

Convection

A conveying or transference of heat or electricity by moving particles of matter.

Converter

A device which changes electrical energy from one form to another. There are several types of converters.

Co-Polymer

A term used to designate that two or more monomers are polymerized together to form a different material.

Copper

The principle electrical conductor.

Copperclad

A thin coating of copper fused to an aluminum core. Used in some building wires (#12 and larger).

Copperweld® (CW)

A copper covering over a high strength steel core used for its corrosion resistance, high electrical conductivity, and ductility. ®Copperweld Enterprises

Cord

A small, very flexible insulated cable.

Cord connector

A portable receptacle which is attached to, or provided with, means for attachment to a flexible cord and which is not intended for fixed mounting.

Cord Sets

Portable cords, fitted with any type of wiring device at one or both ends.

Core

In cables, a term used to denote a component or assembly of components over which other materials are applied, such as, additional components, shield, sheath, or armor.

Corona

A discharge due to ionization of a gas (usually air) due to a potential gradient exceeding a certain critical value.

Corona Initiation Point

The critical value in the application of an electrical potential where corona is first noticed by the detection device.

Corrosion

The prosses or result of a material being eaten or worn away, usually by chemical reaction.

Corrosion Resistant

A device constructed of special materials and/or suitably plated to withstand corrosive environments.

Counter-Clockwise Convention

It is a convention that in any vector diagram, the leading vector be drawn counter-clockwise with respect to the lagging vector, as in the accompanying diagram, where OI represent the vector of a current in a simple alternating current circuit, lagging behind the vector OE or impressed voltage.

Covering

A material applied over a conductor generally for weather protection.

CPE

Jacketing compound based on chlorinated polyethylene.

Crest Factor

The ratio of the peak or maximum value of a wave, to the r.m.s. value. The crest factor of a sine is the square root of 2.

Crimp Termination

A wire termination that is applied by physical pressure of terminal to wire.

Cross Sectional Area

The area of the cut surface of an object cut at right angles to the length of the object.

Cross Talk

Electrical interference between two adjacent insulated conductors whereby a signal in one of the conductors will be picked up by the adjacent conductor.

Cross-Connect

System component where jumper wires and patch cards are used to rearrange communications circuits in order to administer the network. Usually located in a telecommunications closet or equipment room.

Cross-Linked

Inter molecular bonds produced between long chain molecules in a material to increase molecular size by chemical or electron bombardment means, resulting in a change in physical properties in the material - usually improved properties.

CSA

Canadian Standards Association. Test products, provides certification and develops standards for many products.

Cu

Copper

Cube Tap

An adapter that converts one receptacle opening to multiple openings.

Current

The movement of electrons through a conductor; measured in amperes, milliamperes and microamperes.

Current Carrying Capacity

The current a conductor of given size is capable of carrying safely without exceeding its own insulation and jacket temperature limitations.

Current Consumption

Maximum amount of current required to properly operate the photoelectric sensor.

Current Limitation

A fuse operation relating to short ciruits only. When a fuse operates in its current-limiting range, it will clear a short circuit in less than 1/2 cycle. Also, It will limit the instantaneous peak let through current to a value substantially less than that obtainable in the same circuit if that fuse were replaced with a solid conductor of equal impedance.

Current Penetration

The depth a current of a given frequency will penetrate into the surface of a conductor carrying the current.

Current Ratio

The current ratio of a current transformer is the ratio of r.m.s. primary current to r.m.s. secondary current, under specified conditions of load.

Current Sinking

NPN output - refers to a switching output device that allows current flow from the load, through the devices output and then to ground, when in the "on" state.

Current Sinking Sensor (NPN-Transistor)

A current sinking sensor "sinks" current from the load to the negative terminal (-) of the dc voltage supply.

Current Sourcing

PNP output - refers to a switching output device that allows current flow from the devices output, through the load, and then to the ground, when in the "on" state. Considered safer than NPN outputs due to the way current flows when wired up.

Current Sourcing Sensor (PNP-Transistor)

A current sourcing sensor "sources" current from the positive terminal (+) of the dc voltage supply to the load.

Current Tap

An adaptor consisting of a medium-base lampholder extension, with or without integral switch, having one or tow reeptacle openings.

Current Transformer

A transformer designed for series connection in its primary circuit with the ratio of transformation appearing as a ratio of currents.

Current-Limiting Fuse

A fuse which will limit both the magnitude and duration of current flow under short circuit conditions.

Cut-Through Resistance

The ability of a material to withstand mechanical pressure, usually a sharp edge or prescribed radius, without separation.

CV

Continuous Vulcanization – Rubber casing process.

CV-Continuous Vulcanization

Simulatneous extrusion and vulcanization of wire coating materials.

CX

Two-conductor, #18 A.W.G., rubber-insulated, twisted Christmas tree cord, 300V.

CXT

Two-conductor, #18 A.W.G., plastic-insulated, twisted Christmas tree wire, 300V.

Cycle

One complete wave of postive and negative values of an alternating current.

D

Used as a suffix to indicate a twin wire with two insulated conductors laid parallel under an outer, non-metallic covering.

Daisy Chain

A cabling method (topology) of connecting devices in series. Daisy chaining is no longer recommended.

Dark-on Operation

Output mode that will result in an output from a device when light from the emitter is not incident (being received) upon the receiver. The beam is being interrupted, thus creating an output.

DB (Decibel)

The standard unit of measure of signal gain or loss, used in attenuation and crosstalk measurements.

DBWP

Double braided weatherproof cable.

DC

Direct current.

DCR

Direct current resistance.

Decibel

Unit to express differences of power level. Example: The decibel is 10 times the common logarithim of the power ratio. It is used to express power gain in amplifiers or power loss in passive circuits or cables.

Dedicated Circuit

A circuit established to provide control voltage and current to one load or one type of load, such as an electric range or a computer.

Deep Wall Plate

A wall plate that provides greater clearance for device mounting straps than standard wall plates.

Degree Rise

The amount of increase in temperature caused by the introduction of electricity into a unit.

Delay Line

A cable made to provide very low velocity of propagation with long electrical delay for transmitted signals.

Demand Factor

The ratio of the maximum demand of any system to the total connected load of the system, or of the part of the system under consideration.

Demarcation Point

The interface which marks the division between telephone company facilities and private building wiring, where ownership and operational control changes.

Denier

A term describing the weight of a yarn (not cotton or spun rayon) which in turn determines its pysical size. The weight in grams of 9000 meters of yarn.

De-Rating

When two or more dimmers are ganged and heat sinking material is removed, it is important to "de-rate" or lower the wattage rating of the dimmer. This is due to the heat rise cause by the devices.

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.

Design Voltage

Voltage for which cable is designed.

Dessicant

Water or moisture absorbant material used to prevent moisture from damaging packaged equipment or other merchandise.

Detectable Object

Refers to the requirements of an object; size, reflection qualities, light transmission properties, in order for that object to be detected by the photoelectric sensor.

Die

A device used in the drawing of a wire; that element through which the wire is drawn, to achieve a predetermined diameter. A mold used to form a plastic compound around a wire or cable.

Dielectric

An insulating material usually having a very low loss factor (RF cables).

Dielectric Constant

That property (K) of an insulating material which is the ratio of the parallel capacitance (C) of a given configuration of electrodes with the material as the dielectric, to the capacitance of the same electrode configuration with a vacuum as the dielectric.

Dielectric Phase Angle

Angular difference in phase between the sinusoidal alternating potential difference applied to a dielectric and the component of the resulting alternating current.

Dielectric Strength

A term used to describe the limit, without damage of an insulating material, to an applied voltage potential.

Differential (Hyseresis)

The distance between the operating point where the target enters the sensing field (sensor energizes) to the release point where the target leaves the sensing field (sensor de-energizes).

Differential Travel

(Hystereis) The distinctive property of a photoelectric sensor that results in the operation point being different from the release point. This distance is expressed as a % of the total sensing distance of the photoelectric sensor. It is the distance difference between the operate point when approaching the photoelectric, and the release point when moving away from the photoelectric.

Diffuse Reflective

The detection method of a photoelectric sensor used when the photoelectric relies on the object being sensed to reflect the light beam back to the receiver. The emitter/receiver are contained in one unit.

Dimmer

A switch with electronic components that permits variable control of lighting intensity.

Dimming Ballast

A special ballast used with fluorescent dimmers to control the light intensity of fluorescent lamps.

Dip Process

The process of covering a surface by means of dipping it into or through a molten bath of the coating material. This may be followed by dippings or baths into other solutions and/or materials to produce desired results.

Direct Capacitance

The capacitance measured directly from conductor to conductor through a single insulating layer.

Direct Current

An electrical current that flows in one direction only.

Direct Current Resistance

The resistance offered by any circuit to the flow of direct current.

Direct-Current Compensator or Balancer

Comprises two or more similar direct-current machines (usually with shunt or compound excitation) directly coupled to each other and connected in series across the outer conductors a multiple-wire system of distribution, for the purpose of maintaining the potentials of the intermediate wires of the system, which are connected to the junction points between the machines.

Direct-Current Converter

A device which converts direct current to direct current, usually with a change in voltage.

Direction of Lay

The direction, either clockwise or counter-clockwise, of a conductor or group of conductors when looking axially down a cable length.

Directional Angle

The angular range within which an emitter, receiver, emitter/receiver pair or reflector can be rotated or shifted about on the optical axis and still have the photoelectric properly operate.

Disconnecting Switch

A switch which is intended to open a circuit only after the load has been removed by some other means.

Dissipation Factor

The ratio of the conductance of a capacitor, in which the material is the dielectric, to its susceptence; or the ratio of its parallel reactance to its parallel resistance, or the ratio of the power loss to the circulating KVA.

Diversity Factor

The ratio of the sum of the maximum power demand of the subdivisions, or parts of a system, to the maximum demand of the whole system or part of the system under consideration.

DLC

Diesel locomotive cable

Door Switch

A momentary contact switch normally installed in a door-jamb. The switch is activated when the door is opened or closed.

Double Contact Recessed

A lampholder having two "PAD" type recessed contacts and used with high-output fluorescent lamps.

Double Pole Switch

A switch that makes or breaks the connection of conductors of a single branch circuit.

Double Weave

Mesh braid with rows of two strands each.

Double-Current Generator

Supplies both direct and alternating currents from the same winding.

DR

Rubber range & dryer cord (C.S.A.).

Drain Wire

In a cable an uninsulated wire laid over the component or components and used as a ground connection.

Draw Feed Stock

Rod or wire that is subsequently drawn to a smaller size.

Drawing

In the manufacture of wire, pulling the metal through a die or series of dies for reduction of diameter to specified size.

Drip-Proof

Apparatus is designed as drip-proof when it is constructed so that successful operation is not interfered with when falling drops of liquid or solid particles strike or enter the enclosure at an angle of 0 to 15 degrees from vertical.

DRO

Neoprene range & dryer cord (C.S.A.).

DRT

Plastic ranger & dryer cord (C.S.A.).

Dual Coaxial Cable

A configuration consisting of two individually insulated conductors laid parallel or twisted and placed within an overall shield and sheath.

Dual Element Fuse

Fuse with a speacial design that utilizes two individual elements in series inside the fuse tube. One element, the spring actuated trigger assembly, operates on overloads up to 5-6 times the fuse current rating. The other element, the short circuit section, operates on short circuits up to their interrupting rating.

Duct

An underground or overhead tube used for carrying electrical conductors.

Duplex

An adapter that provides two female receptacle openings when plugged into a single receptacle opening.

Duplex Cable

A cable composed of two conductors twisted together, usually one insulated and one bare neutral.

Duplex Receptacle

Two receptacles in a common housing or mounting means which accepts two plugs.

Durometer

A measurement used to denote the hardness of a substance (usually of thermosetting and thermoplastic materials).

Dust-Proof

Apparatus is designed as dust-proof when so constructed or protected that the accumulation of dust with or without the device will not interfere with its successful operation.

Dust-Tight

Apparatus is designated as dust-tight when so constructed that the dust will not enter the enclosing case under specified test conditions.

DV/DT (Delta Voltage/Delta Time)

DV/DT is the rate of change in voltage over a certain time frame.

Dynamotor

A converter with both motor and generator in one magnetic field, either with two armatures, or with one armature having two separate windings.