| WORD | 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 Railroads |
| 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 draw 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. |
| ACTUATOR SOLENOID | The solenoid in the actuator housing on the back of the injection pump which moves the control rack as commanded by the engine controller. |
| ALTERNATING CURRENT (AC) | A flow of electrons which reverses its direction of flow at regular intervals in a conductor. |
| ALTERNATOR | A device which converts mechanical energy into electrical energy. |
| AMBIENT TEMPERATURE | The temperature of the surrounding medium, such as gas, air or liquid, which comes into contact with a particular component. |
| AMMETER | An instrument for measuring the flow of electrical current in amperes. Ammeters are always connected in series with the circuit to be tested. |
| AMPERE | A unit of measure for the flow of current in a circuit. One ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance. The ampere is used to measure electricity much as ‘gallons per minute’ is used to measure water flow. |
| AMPERE-HOUR | A unit of measure for battery capacity. It is obtained by multiplying the current (in amperes) by the time (in hours) during which current flows. For example, a battery which provides 5 amperes for 20 hours is said to deliver 100 ampere – hours. |
| AMPLIFIER | A device of electronic components used to increase power, voltage, or current of a signal. |
| AMPLITUDE | A term used to describe the maximum value of a pulse or wave. It is the crest value measured from zero. |
| ANALOG GAUGE | A display device utilizing a varying current to cause a mechanical change in the position of its needle. |
| ANALOG IC | lntegrated circuits composed to produce, amplify, or respond to variable voltages. They include many kinds of amplifiers that involve analog – to – digital conversions and vice versa, timers, and inverters. They are known as Operational Amplifier Circuits or OP – Amps. |
| ARMATURE | The movable part of a generator or motor. It is made up of conductors which rotate through a magnetic field to provide voltage or force by electromagnetic induction. The pivoted points in generator regulators are also called armatures. |
| ARTIFICIAL MAGNETS | A magnet which has been magnetized by artificial means. It is also called, according to shape, a bar magnet or a horseshoe magnet. |
| ATOM | A particle which is the smallest unit of a chemical element. It is made up mainly of electrons (minus charges) in orbit around protons (positive charges). |
| AUXiliARY SPEED SENSOR | The engine speed sensor located on the engine timing gear cover. It serves as a back – up to the primary engine speed sensor. |
| 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 shield a source from direct view at certain angles, or to absorb unwanted light. |
| Baking | Heating to a low temperature in order to remove gasses. Curing or hardening surface coatings such as paints. |
| Balance Circuit | A circuit arranged so 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 temperature 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 identification. |
| 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. Telecommunication 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 angle 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. |
| BENDIX DRIVE | One type flywheel engaging device for a starting motor. It is said to be mechanical because it engages by inertia. |
| 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 withstand 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 temperature 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 lampholder 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 spools 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 cylindrical 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 Magnetic | A friction brake which is controlled by electromagnetic means. |
| Brake Wire | Wire used in mobile-home, travel and truck trailers to supply current to the electrical braking system. |
| Branch Circuit | A circuit that supplies a number of outlets for lights, appliances, equipment etc. |
| BREAK | See Open. |
| 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. |
| BRUSH | A device which rubs against a rotating slip ring or commutator to provide a passage for electric current to a stationary conductor. |
| 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. |
| Burst Pressure | The maximum pressure that can be applied to a transducer without 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 designed tool for easy cutting of cable |
| Cable Preparation Tool | 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 addition to enclosures. |
| Calibration | The process of setting a measurement instrument by use of standards. |
| CALIBRATION | The determination or rectification of the graduations used on a testing instrument. |
| Campus | A complex 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 intensity. |
| 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, 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. |
| Capacitance 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 probe capacitance will allow the detector to turn the load on or off. |
| Capacitive Coupling | Electrical interaction between two conductors required to maintain that charge. |
| CAPACITOR | A device which stores electrical energy. Commonly used for filtering out voltage spikes. |
| 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 resistance 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. |
| 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 continuous 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 Manufacturers 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 certificate 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 Impedance | The impedance that when connected to the output terminals of a transmission line of any length, makes the line appear infinitely long. The ratio of voltage to current at every point along a transmission line on which there are no standing waves. |
| CHARGE | To restore the active materials in a storage battery by the passage of direct current through the battery cells in a direction opposite that of the discharging current. |
| 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 interrupter 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 cylindrical 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, in consistent 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, surface printing, etc. |
| Color Discrimination | The perception of differences between two or more colors. |
| Color Mark Detector | A sensor designed to differentiate 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 flexibility 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 concentric-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-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 process 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 | Movement of electricity along a conductor. Current is measured in amperes. |
| 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 FLOW | The flow or movement of electrons from atom to atom in a conductor. |
| 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 adapter consisting of a medium-base lampholder extension, with or without integral switch, having one or two receptacle 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. |
| CYCLE | The change in an alternating electrical sine wave from zero to a positive peak to zero to a negative peak and back to zero. |
| CYCLING | The process by which a battery is discharged and recharged. |
| 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. |
| DIAGNOSTIC CODE | A number which represents a problem detected by the engine controller. Diagnostic codes are transmitted for use by on – board displays or a diagnostic reader so the operator or technician is aware there is a problem and in what part of the fuel injection system the problem can be found. |
| 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 (Hysteresis) | 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. |
| DIFFERENTIATOR CIRCUIT | A circuit that consists of resistors and capacitors designed to change a DC input to an AC output. It is used to make narrow pulse generators and to trigger digital logic circuits. When used in integrated circuits it is known as an inverter. |
| 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. |
| DIGITAL IC | lntegrated circuits that produce logic voltage signals or pulses that have only two levels of output that are either ON or OFF (yes or no). Some component output examples are: Diagnostic Codes Output, Pulse-Width-Modulated (PWM) Throttle Output, Auxiliary Speed Output, and Fuel Flow Throttle Output. |
| 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. |
| DIODE | An electrical device that will allow current to pass through itself in one direction only. Also see Zener diode. |
| 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 (DC) | A steady flow of electrons moving steadily and continually in the same direction along a conductor from a point of high potential to one of lower potential. It is produced by a battery, generator, or rectifier. |
| 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. |
| DISCHARGE | To remove electrical energy from a charged body such as a capacitor or battery. |
| 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. |
| DISTRIBUTOR (IGNITION) | A device which directs the high voltage of the ignition coil to the engine spark plugs. |
| DISTRIBUTOR LEAD CONNECTOR | A connection plug in the wires that lead from the sensor in the distributor to the electronic control unit. |
| 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) | The rate of change in voltage over a certain time frame. |
| DYER DRIVE | One type of flywheel engaging mechanism in a starting motor. |
| Dynamotor | A converter with both motor and generator in one magnetic field, either with two armatures, or with one armature having two separate windings. |
| E | Elevator lighting and control cable. Rubber insulation, three overall braids, outer one flame-retardant and moisture resistant. May have steel supporting strand in center, 300V. |
| EC | Electrical conductor (electrical grade aluminum – now known as Alloy 1350). |
| Eccentricity | Like concentricity a measure of the center of a conductor’s location with respect to the circular cross section of the insulation; expressed as a percentage of center displacement of one circle within the other. |
| Edison Base | A lampholder having a threaded internal shell approximately 1″ in diameter which accepts lamp bulbs of the size commonly used for domestic illuminating. |
| Efficiency | The efficiency of an electrical machine or apparatus is the ratio of its useful power output to its total power input. Efficiency is stamped on the nameplate of most domestically-produced electric motors. |
| EIA | (Electronic Industries Association) Industry trade association which works with the Telecommunications Industry Association (TIA) in developing standards. |
| Elastomer | Any elastic, rubber like substance such as natural or synthetic rubber. |
| Electric Arc | Sustained visible discharge of electricity across gap in circuit or between electrodes. Arcing takes place in switches and other make and break devices when a circuit is opened, and at the brushes of a commutator type motor if brush contact is bad. |
| Electric Controller | A device, or group of devices, which serves to control, in some manner, the electric power delivered to the apparatus to which it is connected. |
| Electric Gradient | The space rate of change of potential at a point in the direction of the greatest change. |
| Electrical Degree | One 360th part of a cycle. |
| ELECTRICAL FIELD | The region around a charged body in which the charge has an effect. |
| Electrical Length | The length of cable expressed as degrees of a cycle or fraction of a wavelength for the signal transmitted. The equivalent electrical length of a cable equals physical length times the square root of the dielectric constant. |
| Electrical Load | That part of the electrical system which actually uses the energy or does the work required. |
| ELECTRICITY | The flow of electrons from atom to atom in a conductor. |
| Electro Magnetic | Magentism caused by the flow of an electric current. |
| Electro Motive Force | That force which determines the flow of electricity; a difference of electric potential. |
| Electro Positive | A substance which has a tendency to unite electrons in electrolysis leaving it with a positive charge. |
| ELECTROCHEMICAL | The relationship of electricity to chemical changes and with the conversions of chemical and electrical energy. A battery is an electrochemical device. |
| Electrode | A conductor through which a current enters or leaves an eletrolytic cell, arc furnace, vacuum tube, gas discharge tube or other non-metallic conductor. |
| ELECTRO-HYDRAULIC VALVE | A hydraulic valve actuated by a solenoid through variable voltage applied to the solenoid coil. |
| Electrolier | A lampholder of the Edison base type, having a smaller outside diameter then those in general use. |
| Electrolysis | The production of chemical changes by passage of current through an electrolyte. |
| ELECTROLYTE | Any substance which, in solution, is dissociated into ions and is thus made capable of conducting an electrical current. The sulfuric acid – water solution in a storage battery is an electrolyte. |
| Electrolytic Corrosion | Corrosion by means of electrochemical erosion. |
| Electrolytic Tough Pitch | A term describing the method of raw copper preparation to ensure a good physical and electrical grade copper finished product. |
| ELECTROMAGNET | core of magnetic material, generally soft iron, surrounded by a coil of wire through which electrical current is passed to magnetize the core. |
| ELECTROMAGNETIC CLUTCH | An electromagnetic device which stops the operation of one part of a machine while other parts of the unit keep on operating. |
| ELECTROMAGNETIC FIELD | The magnetic field about a conductor created by the flow of electrical current through it. |
| ELECTROMAGNETIC INDUCTION | The process by which voltage is induced in a conductor by varying the magnetic field so that lines of force cut across the conductor. |
| ELECTRON | A tiny particle which rotates around the nucleus of an atom. It has a negative charge of electricity. |
| ELECTRON THEORY | The theory which explains the nature of electricity and the exchange of ”free” electrons between atoms of a conductor. It is also used as one theory to explain direction of current flow in a circuit. |
| ELECTRONIC CONTROL UNIT (ECU) | General term for any electronic controller. See controller: |
| ELECTRONIC GOVERNOR | The computer program within the engine controller which deterines the commanded fuel delivery based on throttle command, engine speed, and fuel temperature. It replaces the function of a mechanical govnor. |
| ELECTRONIC IGNITION SYSTEM | A system in which the timing of the ignition spark is controlled electronically. Electronic ignition systems have no points or condenser, but instead have a reluctor, sensor, and electronic control unit. |
| ELECTRONICS | The control of electrons (electricity) and the study of their behavior and effects. This control is accomplished by devices that resist, carry, select, steer, switch, store, manipulate, and exploit the electron. |
| Electroplate | The term used to indicate the application of a metallic coating on a surface by means of electolytic action. |
| Electro-Tinned | Electrolytic process of tinning wire using pure tin. |
| ELEMENT | (1) Any substance that normally cannot be separated into different substances. (2) The completed assembly of a battery consisting of negative plates, positive plates, and separators mounted in a cell compartment. |
| Embossing | A means of marker identification by means of thermal indentation leaving raised lettering on the sheath material of cable. |
| Emergency Overloads | Loads which occur when larger than normal currents are carried through a cable or wire over a certain period of time. |
| EMI | Electromagnetic interference or unwanted signal pick-up. One of two types of electrical “noise” caused by varying magnetic fields conducted into branch wiring from inductive load switching. |
| Emitter | The portion or unit of a photoelectric sensor that contains a light source. |
| Enameled Wire | A conductor with a baked-on varnish enamel. |
| Enclosed Cartridge Fuse | A fuse with a tubular body having a terminal on each end and a current-responsive element (link) inside. |
| Ends | In braiding, a term used to denote the number of wires or threads on a braider carrier. |
| Energy | The capacity for doing work. |
| ENGINE CONTROLLER | The electronic module which controls fuel delivery, diagnostic outputs, back – up operation, and communications with other electronic modules. |
| EO | Elevator lighting and control cable. Rubber insulation, cotton braid, neoprene jacket. May have steel supporting strand in center, 300V. |
| EP, EPR, EPM, EPDM | Designations for synthetic rubber based upon ethylene-propylene hydrocarbon. |
| Equipment Room (ER) | A centralized space for telecommunications equipment serving one or multiple buildings. It contains more complex equipment than the telecommunications closet, which serves each floor of a building. |
| Error | The difference between the value indicated by the trandsucer response curve contains points of equal maximum value. |
| ET | Elevator lighting and control cable. Polyvinyl chloride insulation, three braids, flame-retardant and moisture-retardant finish. May have steel supporting strand in center, 300V. |
| Ethernet | The most commonly used network protocol. |
| Excess Gain Ratio | Maximum light available at a given distance. Level of light intensity needed to operate the photoelectric sensor. |
| Excitation Voltage | The external application of an electrical voltage source applied to a transducer for normal operation. |
| Exothermic | Characterized by the liberation of heat. |
| Explosion Proof | A connector so constructed as to meet the requirements of hazardous (classified) locations as defined by the NEC, NFPA-70 |
| Extrusion | The application of a semi-solid plastic or rubber material by forcing it on a conduit or wire passing through the extruder in a continuous fashion. |
| E-Z-C | Special jacketing combining excellent ozones, oil and abrasion resistance, low-temperature flexibility and color retention. |
| F | Flat band metallic armor. |
| F | Fahrenheit |
| Factor of Assurance | The ratio of the voltage at which wire or cable insulation is tested to that at which it is used. |
| Fan Hanger Receptacle | A single receptacle furnished with a cover plate and having a stud or other means for suppporting a wall hung fan. |
| Fan Hum | Noise created by a fan motor when controlled by a standard speed control. |
| Farad | A unit of electric capacity. |
| Far-End Crosstalk (FEXT) | Crosstalk measured at the cable end opposite from where the signal originates. |
| Fast Acting Fuse | A fuse which opens on overload and short circuits very quickly. This type of fuse is not designed to withstand temporary overload currents associated with some electrical loads. |
| Fatigue Resistance | Resistance to metal crystalization that occurs when the conductors or wires break from flexing. |
| FCC | Flexible control cable. |
| FCC | Federal Communication Commission |
| FDDI (Fiber Distributed Data Interface) | An ANSI standard for 100 Mbps fiber physical and data protocols, generally used in “backbone” applications. |
| Feed Through | The practice of wiring a single branch circuit through a device and feeding power to other devices wired downstream. Feeding through a GFI would provide protection to downstream receptacles. |
| FEP | Fluorinated ethylene propylene insulated wire. |
| FEPB | Fluorinated ethylene propylene insulated wire but with glass or asbestos braid. |
| FF-1 | Fixture wire, flexible, rubber insulated, single conductor. 300V, 60°C |
| FF-2 | Same as FF-1 with 600V rating. |
| FFH-1 | Heat-resistant fixture wire otherwise same as FF-1, 300V. |
| FFH-2 | Same as FFH-1 with 600V rating. |
| Fiber (Optical Fiber) | A thin filament of glass or plastic capable of carrying information in the form of light. |
| Fiber Optic Cables | The use of transparent glass or plastic fibers to transmit light by internal reflection. |
| Fiber Optics | Communications scheme which converts electrical energy to light in order to transmit through optical fiber. |
| Fibrous Filler | A material used to fill interstices in cables made from fibers such as cotton, glass, etc. |
| Field Adjustable Trim Potentiometer | A small, typically screwdriver-adjustable, variable resistor. Used to adjust minimum level of light or speed of a fan. |
| FIELD EFFECT TRANSISTOR (FET) | A transistor which uses voltage to control the flow of current. Connections are the source (input), drain (output) and gate (control). |
| Field Wire | A term defining a light, small, wire type usually produced in long lengths for use in communications in the field. |
| Filler | (a) A material used in the cable to fill large interstices between electrical components. (b) A substance, often inert, added to a compound to improve properties and/or decrease cost. |
| Filler (Fuse) | A non-conductive medium filling the inside of a fuse for quenching electric arcs and absorbing energy produced by element or link melting during interruption. |
| Film | Another term to describe thin plastic sheeting. |
| Firestop | A material or device installed in a cable pathway to prevent the passage of flames, smoke and gases |
| FIXED RESISTOR | A resistor which has only one resistance value. |
| Flanged Inlet | A plug which is intended for flush mounting on an appliance or equipment and which serves to connect utilization equipment to a cord connector. |
| Flanged Outlet | A receptacle which is intended for flush mounting on an appliance or equipment which is intended to establish electrical connection with an inserted plug. |
| Flanged Receptacle | A receptacle which is intended for flush mounting on an appliance or on equipment which is intended to establish electrical connection with an inserted plug. |
| Flat Conductor | A wire manuractured in a flattened form as opposed to round, or square, conductors. |
| Flex Life | Ability of a conductor, wire or cable to withstand repeated bending. |
| Floor Receptacle | A receptacle with a protective cover plate intended for mounting flush with the surface of the floor. |
| Fluorescent Lamp | A glass housing that contains phosphorus in a sealed vacuum. When the phosphorus is exited from a voltage charge it becomes ionized and gives off light. |
| Fluorescent Starter | A device rated in watts having a voltage-sensitive switch and a capacitor whose function is to provide a high voltage pulse to start a fluorescent lamp. |
| Flush Wall Plate | A wall plate designed to mount flush with the wall surface or the plane surface of electrical equipment. |
| Flush Wall Plate | A wall plate designed to mount flush with the wall surface or the plane surface of electrical equipment. |
| Flux | (a) A material that helps produce fusion, as solder flux. (b) A continuous flowing or passing, as in the field created by a magnet. |
| Focusable Diffuse | A diffuse reflective photoelectric sensor that either allows the optical axis of the emitter and receiver to be adjusted to a focal point or it utilizes an aperture to focus on an area in front of the sensor. |
| Form Factor | The ratio of the r.m.s. to the average value of a periodic wave. |
| Four-way Switch | A switch which is used in conjunction with two three way switches to control one light or other connected equipment from three or more locations |
| FPM | Feet per minute |
| Frame Size | Motors, like suits of clothes, shoes and hats, come in various sizes to match the requirements of the application. In general, the frame size gets larger with increasing horsepowers or with decreasing speeds. In order to promote standardization in the motor industry, NEMA prescribes standard frame sizes for certain dimensions of standard motors. For example, a motor with a frame size of 56 will always have a shaft height above the base of 3-1/2 inches. |
| Fraying | In cabling, a term used to describe the unraveling of a fibrous braid. |
| FREOUENCY | The number of pulse or wave cycles that are completed in one second. Frequency is measured in Hertz, as in 60Hz (hertz) per second. |
| Frequency | The number of cycles per second. One cycle per second equals one Hertz (Hz). |
| Frequency Converter | Converts the power of alternating current system from one frequency to one more other frequencies. |
| FRMR | Flame-retarding, moisture-resisting finish. |
| FRP | Fiberglass reinforced plastics |
| Full Load Amps | The amount of current the motor can be expected to draw under full load conditions. Also known as Nameplate Amps |
| Full Load Speed | An indication of the approximate speed that the motor will run when it is putting out full rated output torque or horsepower. |
| Full Load Torque | Full load torque is the rated continuous torque that the motor can support without overheating within its time rating. |
| FUNDAMENTAL LAW OF MAGNETISM | The fundamental law of magnetism is that unlike poles attract each other, and like poles repel each other. |
| Fuse | An overcurrent protective device containing a calibrated current-carrying member which melts and opens under specified overcurrent conditions. |
| FUSE | A replaceable safety device for an electrical circuit. A fuse consists of a fine wire or a thin metal strip encased in glass or some fireresistant material. When an overload occurs in the circuit, the wire or metal strip melts, breaking the circuit. |
| Fuse Block or Fuse Holder | A device, designed and intended to hold a fuse and provide the means to connect it to the electrical circuit. Fuse blocks consist of fuse clips, insulator and terminals. |
| Fuse Clip | A conductive mechanical device for accepting and securing the conductive part of a fuse to an electrical terminal or connection point. |
| Fused Circuit Breaker | An integrally fused circuit breaker which combines the design and operating features of a circuit breaker and current-limiting fuse in one package. |
| FX | Single rubber-insulated Christmas tree wire with outer braid. 125V, 60°C |
| FXT | Single plastic-insulated Christmas tree wire. 125V, 60°C |
| G | Rubber-insulated, neoprene, Hypalon or CPE jacketed, portable power cable with two to five #8 A.W.G. or larger conductors with ground wires. |
| Gage | A term used to denote the physical size of a wire. |
| Galvanizing | A coating of some metal part (usually steel or iron) with zinc by dipping or electroplating. |
| Gang | The space required for one wiring device, wall plate etc. |
| Gas-Proof | Apparatus is designed as gas-proof when so constucted or protected that the specified gas will not interfere with successful operation. |
| Gas-Tight | Apparatus is designed as gas-tight when so constructed that the specified gas will into enter the enclosing case under specified test conditions. |
| GATE | A logic circuit device which makes a YES or NO (one or zero) decision (output) based on two or more inputs. |
| Gauge Pressure (PSIG) | A measure of pressure reference to atmoshperic pressure. |
| General Purpose Fuse | A fuse which meets industry standards for overload and short circuit protection as well as physical dimensions. This fuse type is tested and certified by nationally recognized testing laboratories and may be applied in accordance with the National Electrical Code and the Canadian Electrical Code to provide main, feeder and branch circuit protection. |
| Generator | A machine used to change mechanical energy into electrical energy. |
| GENERATOR | A device which converts mechanical energy into electrical energy. |
| GFCI (Ground Fault Circuit Interupter) | A personnel protection device that detects current leakage to ground on the load side and removes power to the receptacle. |
| G-GC | A portable power cable similiar to type G, but also having a ground check conductor to monitor the continuity of the Grounding Circuit. |
| Giga | A numerical prefix denoting one billion as a gigacycle is one billion cycles |
| GIGA-Hertz | One billion hertz equal to 1 KMC (1000 megacycles). |
| Glass Braid | Used to provide thermal and/or mechanical protection to the underlying insulation of certain types of conductors. |
| Glass Fuses | A loose term describing a group of low voltage fuses, with glass or ceramic bodies, having dimensions smaller than midget fuses. Also called “miniature” fuses, they are typically 1/4″ x 1-1/4″, 1/4″ x 1,” or 5mm x 20mm. These fuses are used to protect electronic circuits or components. |
| Glow Discharge | A fluorescent starter that starts a lamp very rapidly and will continue to try to start a failed lamp, resulting in the lamp flickering until the lamp is replaced. |
| GOR | Gasoline and oil-resistant wire |
| GRID | A wire mesh to which the active materials of a storage battery are attached. |
| Grip | a flexible wire mesh cable holding device |
| 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 | A ground occurs when any part of a wiring circuit unintentionally touches a metallic part of the machine frame. |
| Ground Check Conductor | A conductor used in mining cables to monitor the continuity of the grounding circuit, so that a discontinuity or “open” in the grounding circuit causes the power conductors to be de-energized. Also called a “ground monitoring” conductor. Used in Types G-GC, SHD-GC, and MPF-GC. Abbreviated “GC”; identified by yellow colored insulation. |
| Ground Conductor | A conductor (normally non-current carrying) which is intentionally connected to earth ground (it is identified as the bare or green conductor) to provide an intentional path for fault current to ground. |
| Ground Support Cable | A cable construction, usually rugged and heavy, for use in ground support control or power systems. |
| GROUNDED CIRCUIT | A connection of any electrical unit to the frame, engine, or any part of the tractor or machine, completing the electrical circuit to its source. |
| Grounded Conductor | A system or circuit conductor that is intentionally grounded; usually colored white. |
| Grounding | An adapter that converts a two wire receptacle opening to a two pole three wire grounding receptacle opening. |
| Grounding Conductor | A conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode or electrodes; usually colored green. |
| Grounding Parts | Parts that are intentionally connected to ground. |
| Grounding terminal | A designated terminal screw or pressure wire connector located on the internal wall of the field wiring compartment for connection to an equipment grounding conductor from the panelboard. |
| GROWLER | A device for testing the armature of a generator or motor. |
| GSA | (General Services Administration, Federal Supply Service) The U.S. Government administration responsible for the approval of Federal Specifications used in the purchase of products by all Federal agencies. |
| GTO | Gas tube sign and oil-burner ignition cable. 5,000V-15,000V |
| H | Shielded power cable. Multi-conductor cables have paper or varnished cambric insulation applied directly over individual conductors. Spiralled metallic shielding tape over insulation with overall protective covering. |
| Hard Drawn Copper Wire | Copper wire that has been drawn to size and not annealed. |
| Harness | A term used to describe a group of conductors laid parallel or twisted by hand, usually with many breakouts, laced together or pulled into a rubber or plastic sheath, used to interconnect electrical circuits. |
| Hash Mark Stripe | A non-continuous, helical stripe applied to a conductor for circuit indentification. |
| HC | Two or more conductor heater cord, asbestos and rubber insulation with cotton braid over each conductor. Twisted, no overall covering. |
| HDP | High density polyethylene |
| Headroom | The overhead of margin, expressed in decibels, by which a communications system exceeds minimum requirements. |
| Heat Distortion | Distortion or flow or a material or configuration due to the application of heat. |
| Heat Seal | In cabling, a method of sealing a tape wrap jacket by means of thermal fusion. |
| Heat Shock | A test to determine stability of a material by sudden exposure to a high temperature for a short period of time. |
| Heat Sink | A metal plate used for absorbing or removing heat for the switching device in a dimmer or fan speed control |
| Heat Sink Dimmer/Fan Speed Control | Any dimmer or fan speed control that mounts onto a NEMA standard switch box and onto the surface of the wall itself. Heat sink dimmers and fan controls will not accept a traditional wall plate and usually are supplied with their own unique cover. |
| Helical Stripe | A continuous, colored, spiral stripe applied over the outer perimeter of an insulated conductor for circuit indentification purposes. |
| Helix | A spiral winding. |
| Henry | An electrical unit denoting the inductance of a circuit in which a current varying at the rate of one ampere per second produces an electromotive force of one volt. |
| High Inertia Load | These are loads that have a relatively high flywheel effect. Large fans, blowers, punch presses, centrifuges, commercial washing machines and other types of similar loads can be classified as high inertia loads. |
| High Speed Fuses | Fuses with no intentional time-delay in the overload range and designed to open as quickly as possible in the short-circuit range. These fuses are often used to protect solid-state devices. |
| High Voltage Fuses | Fuses rated 34,500 volts and above. |
| HMP | High molecular weight polyethylene. |
| Home Run | Also known as star topology, a cabling system where indiviual calbes are run directly from the telecomunnications closet to each information outlet. |
| Hook-up Wire | A wire used for low current, low voltage (under 1000V) applications internally within enclosed electronic equipment. |
| Horizontal Cabling | The portion of the wiring system extending from the workstation to the horizontal cross-connect in the telecommunications closet. |
| Horizontal Cross-Connect | The cross-connection between horizontal and other cabling, such as backbone cabling. |
| Horizontal Length | The cable distance from the workstation to the telecommunications closet cross-connect, a maximum of 295 ft. (100 meters). |
| Horizontal Stripe | A colored stripe running horizontally with the axis of a conductor, sometime called a longitudinal stripe, used as a means of circuit identification. |
| Horsepower Rated | A device having a marked horsepower rating intended for control of motor loads. |
| Hospital Grade | A device constructed to meet performance requirements of high abuse areas found in hospital locations, tested to “Hospital Grade” requirements of Underwriters Laboratories Standard UL498 |
| Hospital Only | A connector which is listed by Underwriters Laboratories INC for use in health care facilities. |
| Hot Dip | A term denoting the covering of a surface to be coated into a molten bath of the coating material. |
| HPD | Rubber and asbestos-insulated heater cord. No braid on individual conductors but with braid overall. Also made with neoprene insulation and no asbestos or PVC/NBR. |
| HPN | Two-conductor, neoprene-insulated heater cord. Parallel construction. For use in damp locations. |
| HS | Rubber and asbestos-insulated heater cord. Cotton serve and rubber-jacketed overall. For use in damp locations #14 or #12 conductors. Also made with neoprene insulated inners and asbestos. |
| HSJ | Same as type HS but with #18 or #16 conductors and differing thickness of jacket. |
| HSJO | Same as type HSJ but with neoprene jacket. |
| HSO | Neoprene jacketed heater cord. |
| Hub | Equipment which serves as a centralized connection point for a network or a portion of network. Hubs contain multiplexing, switching, and bridging functions and are not considered part of the cabling infrastructure. |
| HV | High voltage |
| HW | Radio hookup wire with polyvinyl insulation. With or without nylon jacket, braid or shield, 2500V. |
| Hybrid Cable | A multi-conductor cable containing two or more types of component. |
| HYDROMETER | An instrument for measuring specific gravity. A hydrometer is used to test the specific gravity of the electrolyte in a battery. |
| Hygroscopic | Readily absorbing and retaining moisture. |
| Hypalon® | Dupont trandmark for chlorosulfonated polyethylene (CSPE) synthetic rubber. |
| Hysteresis | The error defined by the maximum deviation of measured output from a best fit straight line during any one calibration cycle. |
| I | Interlocked armor of aluminum, bronze or steel. |
| IACS | International Annealed Copper Standard. |
| ID | Internal Diameter |
| IEC | The International Eletrotechnical Commission, writes recommended safety and performance standards for electrical products. |
| IEEE | Institute of Electrical and Electronic Engineers. |
| Ignition Cable | A cable designed primarily for automotive ignition system. |
| IGNITION CONTROL UN IT | The module that contains the transistors and resistors that controls the electronic ignition. |
| Illuminated | A device that, when connected to an electrical circuit is lighted in the area of the face or handle. |
| Impact Strength | A test designed to ascertain the punishment a cable configuration can absorb, without physical or electrical breakdown, by impacting with a given weight, dropped a given distance, in a controlled environment. |
| Impedance | The ratio of the effective value of the potential difference between two terminals to the effective value of the current flow produced by that potential difference. |
| Incandescent | Lampholders of the threaded screw shell types for use with standard sizes of incandescent bulbs, having threaded bases. |
| Incandescent Lamp | A light bulb which contains a filament in a sealed vacuum. When voltage is applied to the filament, it heats, producing light. |
| Individual Strand Diameter | The diameter of an individual strand of a stranded wire. |
| Inductance | That property of an electrical circuit by virtue of which a varying current induces an electromotive force in that circuit, or in an adjacent circuit. |
| INDUCTANCE | The property of an electric circuit by which an electromotive force (voltage) is induced in it by a variation of current either in the circuit itself or in a neighboring circuit. |
| Induction Generator | An induction machine driven above synchronous speed, used to convert mechanical power to electrical power |
| Induction Motor | An alternating current motor, either single phase or polyphase, comprising independent primary and secondary windings, in which the secondary receives power from the primary by electromagnetic induction. |
| Inductive Load | Electrical devices made of coiled or wound wire that create a magnetic field when energized. Components such as motors, solenoids and coils are all inductive loads. |
| INDUCTOR | A coil of wire wrapped around an iron core. |
| Inductor Alternator | An alternator in which both field and armature windings are stationary and in which the voltage is produced by varying the flux linking the armature winding. |
| Inlet (Male Base) | A plug which is intended for flush or surface mounting on an appliance or equipment and which serves to connect utilization equipment to a connector. |
| Instrument Transformer | A transformer (current or potential) suitable for use with measuring instruments; i.e. one in which the conditions of the current, voltage and phase angle in the primary circuit are represented with acceptable accuracy in the secondary circuit. |
| Insulated Conductor | A conductor to which an insulating material has been applied to withstand a predetermined voltage gradient. |
| INSULATED GATE FIELD EFFECT TRANSISTOR (IGFET) | A diffused transistor which has an insulated gate and almost infinite gate – channel resistance. |
| Insulation | A non-conductive material usually surrounding or separating two conductive materials. Often called the dielectric in a radio frequency cable. |
| Insulation Class | The insulation class is a measure of the resistance of the insulation components of a motor to degradation from heat. Four major classifications of insulation are used in motors. They are, in increasing thermal capabilities, A,B,F and H. |
| Insulation Displacement Connection | An electrical connection made by “punching down” a wire in a terminal which cuts through the insulation to make contact with the conductor. |
| Insulation Resistance | That property of an insulating material which resists electrical current flow through the insulating material when a potential difference is applied. The resistance measured between two insulated points on a transducer when a specified DC voltage is applied. |
| Insulation Shield | A layer of semi-conducting material or tape applied directly over the insulation of high voltage cabes, usually on cables rated at over 5000 volts. In addition to this layer, some cable constructions include a layer of non-magnetic metal overlapping tape or a number of helically applied small wires. |
| Insulator | A non-conducting substance such as poreclain, plastic, glass, rubber, etc. |
| INSULATOR | A substance or body that resists the flow of electrical current through it. Also see ‘Conductor:’ |
| Integral Belt | In a cable, a layer of insulation or semi-conductive material applied usually by extrusion over two or more insulated, twisted or parallel conductors, to form a round smooth diameter |
| INTEGRATED CIRCUIT (IC) | An electronic circuit which utilizes resistors, capacitors, diodes, and transistors to perform various types of operations. The two major types are Analog and Digital Integrated Circuits. Also see ‘Analog IC’ and ‘DigitaI IC.’ |
| INTEGRATOR CIRCUIT | A circuit that consists of resistors and capacitors and functions as a filter which can pass signals only below a certain frequency. |
| Interchangeable | A device or combination of devices, each individually housed and having common mounting dimensions and intended for field installation on a single or multiple opening mounting strap. Also known as despard. |
| Interconnecting Wire | A type of wire for external use in electronic equipments where exposed to physical abuse. Interconnecting wire encompasses both control and power circuits. |
| Intermediate Cross-Connect (IC) | The cross-connection between the first and second level of backbone cabling. |
| Intermediate lampholder | A lampholder with a threaded screw shell accepting intermediate size incandescent lamps with thereaded bases that are approximately 13/32″ in diameter. Most often used in decorative lighting such as candle scones, etc. |
| Internal Diameter | The diameter of some internal part or composite of an object which in this case would pertain to wire, cable, etc. |
| Interrupting Rating or Capacity | Interrupting (breaking or rupturing) capacity is the hightest r.m.s. current at normal voltage which a device can interrupt under prescribed conditions. |
| Interstice | In cable contruction, the space, valley or void left between or around the cabled components. |
| INVERTER | A device with only one input and one output; it inverts or reverses any input. |
| ION | An atom having either a shortage or excess of electrons. |
| Ionization | The act of splitting into or producing ions. |
| IP Rating | Rating system established by IEC Publications 144 and 529 which defines the degree of protection provided by electrical enclosures with respect to person, other electrical equipment and the ingress of water. |
| IPE | Irradiated polyethylene tape. |
| IPM | Inches per minute |
| IR | Insulation Resistance |
| Irradiation | The exposure of a material to high energy emissions. In insulations for the purpose of favorably altering the molecular structure. |
| Isolated Ground | A grounding type device in which the equipment ground contact and terminal are electrically isolated form the receptacle mounting means. |
| ISOLATION DIODE | A diode placed between the battery and the alternator. It blocks any current flow from the battery back through the alternator regulator when the alternator is not operating. |
| J | Asphalted jute, non-metallic armor |
| Jack | A device into which a plug is inserted in order to make electrical contact in a communication circuit. |
| Jacket | A material covering over a wire insulation or an assembly of components. An overall jacket on a complex cable grouping is also often referred to as a sheath. |
| Joule | The unit of work. |
| Joule Rating | The short duration peak energy rating of a surge supression device. The higher the joule rating the longer the expected life of the device. |
| Jumper Wire | A short length of twisted pair cable used to route a circuit between two cross-connect termintation points. |
| Junction Box | A box used in an electrical circuit to enclose and permit access to electrical connections. |
| K | Constant used to denote insulation resistance. |
| KCM | 1000 circular mils |
| Key Lampholder | A lampholder with a flat or round “key” projecting from its side, which when turned operates an interanal switching mechanism. |
| Kilocycle | A term denoting one thousand cycles. |
| Kilovolt | A term denoting one thousand volts. |
| Kilowatt | A term denoting one thousand watts. |
| KV | 1000 Volts |
| KVA | Kilovolt Amperes |
| KW | Kilowatt, 1000 watts of power |
| L | Denotes lead sheath |
| Lace | Strand of wire usually the same material as the mesh used to weave closed a split mesh. |
| Lacquer | The term used in cable manufacture to designate the liquid resin or compound applied to a fibrous braid to prevent fraying, wicking, moisture absorption, etc., in the braid. |
| Laminated Tape | A term used to describe a tape consisting of two or more layers, usually each layer being a different material, sealed or laminated together to form one tape. |
| Lampholder | A device that establishes mechanical and electrical connection to an inserted lamp. |
| LAN (Local Area Network) | A network of computers and peripheral devices with a limited area such as a department, single building, or campus environment. |
| Lateral Approach | When the target to be detected approaches the sensing face from the side (slide-by). |
| Lay | A term used in cable manufacturing to denote the distance, of advance of one member of a group of spirally twisted members, in one turn, measured axially. |
| Lays | The twists in a twisted pair cable which, when varied, limit the potential for interference in a twisted pair cable. |
| Leakage Current | The amount of current that flows through, or leaks from, the output of an energized device when the device is in the OFF-STATE. Most common problem involves leakage current when a device is wired as an input to a Programmable Controller. Leakage current should be less than 1.7 mA. |
| LED (Light Emitting Diode) | Solid State device which produces visible red, green, or yellow light or invisible infrared light radiation. |
| LESCW | Low energy safety circuit wire. |
| Life Cycle | A test performed on a material or configuration to determine the length of time before failure in a controlled, usually accelerated, environment. |
| Light | Measured in wavelength, wavelenghts of visible light range between 400 and 700 nanometers. |
| LIGHT EMITTING DIODE (LED) | A solid – state display device that emits infrared light when a forward – biased current flows through it. |
| Light Incident | The condition met when light from the emitter is reaching, or incident upon, the receiver. |
| Light Interrupted | The condition met when light from the emitter is not reaching, or incident upon, the receiver. |
| Light Source | Type of light used in the emitter portion of the photoelectric. Most common, pulse modulated LED or incandescent lamp. |
| Lighted Handle | A switch with an integral lamp in the actuator that lights when the switch is in the OFF position. |
| Light-on Operation | Output mode that will result in an output turning on when light from the emitter is incident upon the receiver. |
| Light-Powered Sensor (3 or 4-Wire) | A sensor that draws its operating current (burden current) directly from the line. Its operating current does not flow through the load, and a minimum of three connections (3-wire) are required. A 4-wire sensor has complimentary outputs and requires four connections. |
| Limiter | A special purpose fuse which is intended to provide short circuit protection only. |
| Line Voltage | The voltage existing in a phase conductor in an electrical circuit, either phase to ground (neutral) or phase to phase. |
| LINES OF FORCE | Invisible lines which conveniently illustrate the characteristics of a magnetic field and magnetic flux about a magnet. |
| Link | The basic, permanently installed, horizontal cabling path between the work area outlet and telecommunications closet cross-connect. Often referred to as the contractor link. |
| LIQUID CRYSTAL DISPLAY (LCD) | A display device utilizing a special crystal fluid to allow segmented displays. |
| Litz Wire | A conductor made up of several insulated twisted wires to reduce skin effect and lower radio and frequency losses. |
| LMP | Low molecular weight polyethylene. |
| Load | Any device which current flows through and has a voltage drop across it. |
| Load Factor of a Machine, Plant, or System | The ratio of the average power to the peak power during a specified period of time. In each case, the interval of maximum load and the period over which the average is taken should be definitely specified. The proper interval and period are usually dependent upon local conditions and upon the purpose for which the load factor is to be used. |
| Load Types | Constant Horsepower – The term is used in certain types of loads where the torque requirement is reduced as the speed is increased and vice-versa. The constant horsepower load is usually associated with metal removal applications such as drill presses, lathes, milling machines and other similar types of applications. Constant Torque – is a term used to define a load characteristic where the amount of torque required to drive the machine is constant regardless of the speed at which it is driven. For example, the torque requirement for most conveyors is constant. Variable Torque – Variable torque is found in loads having characteristics requiring low torque at low speeds and increasing values of torque as the speed is increased. Typical examples of varibale torque loads are centrifugal fans and centrifugal pumps. |
| Load-Break Switch | A switch which is designed for, and intended to open a circuit which may be under load. |
| Load-Powered Sensor | A sensor that draws its operating current (leakage current) through the load. The sensor is always in series with the load and only two connections are required. |
| Locked Rotor Amps | Also known as starting inrush, this is the amount of current the motor can be expected to draw under starting conditions when full voltage is applied. |
| Locking (Turnlock) | A device is designated to lock in place when it is rotated in a clockwise direction. The device can then only be removed when turned in a counterclockwise direction. |
| Longitudinal Wrap | A tape applied longitudinally with the axis of the core being covered, as opposed to a helical, or spiral, tape wrapped core. |
| Loop Resistance | The total resistance of two conductors measured round trip from one end (twisted pair, shield and conductor, etc.). |
| Loss Factor | The loss factor of an insulating material is equal to the product of its dissipation and dielectric constant. |
| Low Loss Dielectric | An insulating material such as polyethylene, that has a relatively low dielectric loss making it suitable for transmission of radio frequency energy. |
| Low Noise Cable | A cable configuration specially constructed to eliminate spurious electrical disturbances cause by capacitance changes or self generated noise induced by either physical abuse or adjacent circuitry. |
| Low Voltage Fuses | Fuses rate 600 volts and below. |
| Lug | A term commonly used to describe termination, usually crimped or soldered to the conductor, with provision for screwing down to a terminal. |
| Lumiline Lampholder | A special type of “disc” contact lampholder that only fits tubular incandescent lamps of the “lumiline” type. Commonly used in bathroom fixtures, store display case fixtures, etc. |
| LV | Low voltage |
| LW | Radio hookup wire with polyvinyl insulation. With or without nylon jacket, braid, or shielding braid. 300V |
| M | Suffix indicating two or more insulated, twisted conductors under an outer, non-metallic covering. |
| M.O.V. | Metal Oxide Varistor, primary component of TVSS. |
| MAGNET | A body which has the property of at. tracting iron or other magnets. Its molecules are aligned. |
| Magnetic Field | The region within which a body or current experiences magnetic force. |
| MAGNETIC FIELD | That area near a magnet in which its property of magnetism can be detected. It is shown by magnetic lines of force. |
| Magnetic Flux | The rate of flow of magnetic energy across or through a surface (real or imaginary). |
| MAGNETIC FLUX | The flow of magnetism about a magnet exhibited by magnetic lines of force in a magnetic field. |
| MAGNETIC INDUCTION | The process of introducing magnetism into a bar of iron or other magnetic material. |
| MAGNETIC LINES OF FORCE | Invisible lines which conveniently illustrate the characteristics of a magnetic field and magnetic flux about a magnet. |
| MAGNETIC MATERIAL | Any material to whose molecules the property of magnetism can be imparted. |
| MAGNETIC NORTH | The direction sought by the north pole end of a magnet, such as a magnetic needle, in a horizontal position. It is near the geographic north pole of the Earth. |
| MAGNETIC PICKUP ASSEMBLY | The assembly in a self – integrated electronic ignition system that contains a permanent magnet, a pole piece with internal teeth, and a pickup coil. These parts, when properly aligned, cause the primary circuit to switch off and induce high voltage in the secondary windings. |
| MAGNETIC SOUTH | The opposite direction from magnetic north towards which the south pole end of a magnet, such as a magnetic needle, is attracted when in a horizontal position. It is near the geographic south pole of the Earth. |
| MAGNETIC SWITCH | A solenoid which performs a simple function, such as closing or opening switch contacts. |
| MAGNETISM | The property inherent in the molecules of certain substances, such as iron, to become magnetized, thus making the substance into a magnet |
| Main Cross-Connect (MC) | A cross-connect used with first level backbone, entrance, or equipment cables. |
| Maintained Contact Switch | When the actuator is moved to the ON postition, this switch makes and retains the circuit contact until the actuator is moved to the OFF position. |
| Manual Controller | A horsepower rated switch without overload protection used for the operation of small A.C. or D.C. motors. |
| Manual Reset | A fluorescent starter that automatically deactivates a failed lamp to eliminate flickering. A reset button is provided on the starter to activate the circuit after lamp replacement. |
| Marked Ratio | The marked ratio of an instrument transformer is the ratio of the rated primary value to the rated secondary value as stated on the nameplate. |
| Marker Tape | A tape laid parallel to the conductors under the sheath in a cable, imprinted with the manufacturer’s name and the specification to which the cable is made. |
| Marker Thread | A colored thread laid parallel and adjacent to the strand in an insulated conductor which identifies the manufacturer and sometimes the specification to which the wire is made. |
| Master Switch | A switch which serves to dominate the operation of contactors, relays and auxiliary devices of an electric controller. |
| Maximum Load | The most current that can flow through a device continually, without damaging the device. |
| Mbps (MegaBits Per Second) | One million bits per second. |
| MC | Denotes cable with interlocking metal tape or corrugated tube enclosure. |
| MCM | Thousand circular mils; e.g. 500 MCM is 500,000 circular mils. |
| Medium Base Lampholder (Edison) | The most common type of screw-in lampholder found in everyday lighting fixtures, table lamps , and accepting incandescent bulbs with screw bases approximately 1″ in diameter. |
| Medium Voltage Fuses | Fuses rated from 601 volts to 34,500 volts. |
| Megacycle | One million cycles. |
| Megaohm | One million ohms. |
| Megavolt | One million volts. |
| Megawatt | One million watts. |
| Melt Extrude | To heat a material above its crystalline melt point and extrude it through an orifice. |
| Melting Time | The amount of time required to melt the fuse link during a specified overcurrent. |
| Mesh | The tubular open braid portion of a wire mesh grip |
| Mesh Termination | The method of securing woven strands at the ends of a wire mesh grip. |
| Messenger | A bare cable used for its strength characterstics to support power conductors and insulated power cables. A messenger can be used as a conductor, partial conductor, or non-conductor. |
| Method of Detection | Sensing technique used by the photoelectric sensor. Three types: Thru-Beam, Retroreflective, or Diffuse Reflective. |
| MFT | Abbreviation for 1000 feet. |
| MHD | Medium hard drawn. |
| Mho | An electrical unit of conductivity, being the conductivity of a body with resistance of one ohm. |
| MI | One or more conductors insulated with highly compressed refractory minerals and enclosed in a liquid-tight and gas-tight metallic tube sheathing. |
| Micro Fuses | Term describing the smallest sizes of fuses, usually mounted on, or used to protect, printed circuit boards or small electronic components. |
| Microfarad | One millionth of a farad. |
| Microhenry | One millionth of a henry. |
| Microinch | One millionth of an inch. |
| Micrometer | An instrument used for measuring diameter usually in thousandths of an inch. |
| Microprocessor | Single chip computer element containing the control unit, central processing circuitry; arithmethic an logic function |
| MICROPROCESSOR | An integrated circuit combing logic, amplification and memory functions. |
| Microware | A short electrical wave usually a wave length of less than 30 cm. |
| Microwave Frequency | The frequency of a microwave usually above 1000 megacycles per second. |
| Midget | A device with a body diameter smaller than those devices of a similar rating. |
| Midget Fuse | A term describing a group of fuses used for supplementary circuit or component protection, all having dimensions of 1-1/2″ long and 13/32″ diameter. |
| Mil | One one thousandth of an inch |
| Milivolt | One one thousandth of one volt. |
| MILLIAMPERE | 1/1,OOO,OOO ampere. |
| Miniature Lampholder | The smallest screw-in type lampholder accepting incandescent lamp bulbs of approximately 3/8″ diameter commonly used in games, flashlights and the smallest Christmas tree bulbs. |
| Minimum Load | Minimum current that the external load must draw to ensure proper operation of the photoelectric sensor. Most often associated with standard AC-two wire devices. |
| Mining Cable | A flame retardant cable especially constructed to withstand long time immersion or exposure to moisture for underground use in the environment of a mine or tunnel. |
| Mis-match | A termination having a different impedance than that for which a circuit or cable is designed. |
| MKS | Meter-kilogram-second |
| ML | Single-conductor, paper-lead cables twisted together without overall covering. Type A – AVC mine locomotive cable; Type B – motor lead wire. |
| MLD | (Multi-Location Dimming) This is achieved through the use of specific components designed to interface and allow dimming control from any location, master or remote. In a true MLD situation, the master unit performs all dimming and switching functions. The remote units provide input to the master (i.e. dim, bright, on or off, as desired). |
| MM | Mining machine cable. |
| Modular Jack | A female telecommunications connector, which is mounted in a fixed location. Jacks are specified in IEC 603-7 and FF Part 68 Subpart F. |
| Modular Plug | A male telecommincations connector, specified in IEC 603-7 and FCC part 68 subpart F. |
| Modulus of Elasticity | The ratio of stress to strain in an elastic material. |
| Mogul Lampholder | The largest screw-in type of lampholder accepting incandescent lamp bulbs having screw bases approximately 1 1/2″ in diameter. Used in street lighting fixtures and industrial high bay fixtures. |
| Moisture-Resisting | Apparatus is designed as moisture-resisting when so constructed or treated that it will not be readily injured by moisture. |
| Molded On | An adapter that is factory molded to a length of flexible cord. |
| Molded-Case Circuit Breaker | A circuit breaker which is assembled as an integral unit in a supporting and enclosing housing of molded insulating material. |
| MOLECULE | A unit of matter which is the smallest portion of an element or compound that retains chemical identity with the substance in mass. It is made up of one or more atoms. |
| Momentary Contact | A switch which establishes circuit contact when its actuator is moved to and held in the ON postion. The circuit is broken when the actuator is allowed to return, of itself, to the OFF postion (such a switch may also be furnished to operate in the opposite mode). |
| Mono filament | A term denoting a single strand filament as opposed to a braided or twisted filament. |
| Monomer | A term denoting a single property or ingredient. A molecule of low molecular weight used as a starting material for polymerization to produce molecules of larger molecular weight called polymers. |
| Motor | A machine which converts electrical power into mechanical power. |
| MOTOR | A device which converts electric energy into mechanical energy. |
| Motor-Generator Set | A conversion device consisting of one or more motors mechanically coupled to one or more generators. |
| MPF | Mine power feeder. 5-8-15KV |
| MRFR | Moisture resistant, flame-retardant finish. |
| MSHA | Mine Safety and Health Administration, U.S. Dept. of Labor. Establishes standards and safety requirements for mines. “MSHA” may be printed on cables that have been accepted for listing as flame-resistant. |
| MTW | Thermoplastic-insulated machine tool wire. 90°C to 105°C, 600V |
| MUL TIMETER | A testing device that can be set to read ohms (resistance), voltage (force), or amperes (current) of a circuit. |
| Multiconductor | More than one conductor within a single cable complex. |
| Multimedia | Applications which communicate information using more than one cabling means. |
| Multimode Optical Fiber | An optical fiber cable that allows light to travel in many bound modes; used in LAN applications. Multimode fibers have a larger core than single mode (core/cladding 62.5/125 micrometers) |
| Multiple | An adapter that is attached to the power cord for equipment that provides an additional receptacle opening at the top of the adapter. |
| Multiple Weave | Wire mesh grips woven utilizing single, double and triple strand of each wire material. |
| Multiplexing | Combining a number of individual messages over a common path – usually by frequency division or time division. |
| Multi-User Telecommuincations Outlet Assembly | A device grouping several telecommunications outlets into one location. |
| Mutual Capacitance | Capacitance between two conductors when all other conductors including ground are connected together and then regarded as an ignored ground. |
| MUTUAL INDUCTION | Occurs when changing current in one coil induces voltage in a second coil. |
| Mutual Interference Protection | A feature in photoelectric sensors that eliminates false-singaling between similar mounted next to, or in close proximity to each other. |
| MV | Medium voltage 5-35KV |
| MW | Radio hookup wire with polyvinyl insulation and plain or nylon jacket, or braid, or shield, 1000V. |
| MYD | Marina Yard and Dock Cable. |
| Mylar® | A synthetic compound with high dielectric qualities. A product of Dupont®. Usually sold in film form. |
| N.P.S. | National Pipe Straight Thread |
| N.P.T. | National Pipe Tapered Thread |
| Narrow Wall Plate | A cover plate designed for flush mounting on narrow partitions having a width dimension of two inches or less. |
| NATURAL MAGNET | A magnet which occurs in nature, such as a lodestone. Its property of magnetism has been imparted by the magnetic effects of the Earth. |
| NBR/PVC | (Same properties of EZC) A blend of acrylonitrile – butadiene rubber and polyvinyl chloride (PVC). Used for jacketing. |
| N-Conductor Cable | A cable having N-conductors that are insulated from one another. “N” respresents the number of insulated conductors in the cable. |
| N-Conductor Concentric Cable | A cable composed of an insulated central conductor with tubular stranded conductors concentrically twisted around it and separated from each other by layers of insulation. |
| Near-End Crosstalk (NEXT) | Electrical noise coupled from one pair of wires to another, measured from where the signal is transmitted. |
| NEC | National Electrical Code |
| NEC Dimensions | These are dimensions once referenced in the National Electrical Code. They are common to Class H and K fuses and provide interchangeability between manufacturers for fuses and fusible equipment of given ampere and voltage ratings. |
| NEGATIVE | Designating or pertaining to a kind of electricity. Specifically, an atom that gains negative electrons is negatively charged. |
| Negative charge | The condition in which a body has more than the normal quantities of negative electrons; more negative electricity than an uncharged or neutral body. |
| NEMA Ratings | Standards which define a product, process or procedure taking several considerations into account: nomenclature, composition, dimensions, construction, tolerances, safety, operational characteristics, quality, performance, electrical rating, testing, and the service for which it was intended. Prepared by the National Electrical Manufacturers Association (NEMA). |
| Neo-Contaminating Compound | A compounded material that will not leach ingredients so as to contaminate or degrade adjacent materials under given environmental conditions. |
| Neoprene | Trade name for polychloropene, used for jacketing (SEE polychlorpene). |
| Neper | An electrical unit similiar to decibel, used to express the ratio between two amounts of power existing at two distinct points. A neper is 8.686 decibels. |
| Network | An interconnection of computers, peripherals, and data/voice communications facilities. |
| Neutral Conductor | In multiphas circuits the conductor used to carry unbalanced current and in single phase systems the conductor used for a return current path. |
| NEUTRON | An uncharged elementary particle. Present in all atomic nuclei except the hydrogen nucleus. |
| NFPA | (National Fire Protection Association) An organization devoted to promoting the science and improving the methods of fire protection. |
| NM | Non-metallic sheathed cable, braid or plastic covered. For dry use, 90°C conductor rating, 60°C ampacity. |
| NMC | Non-metallic sheathed cable, plastic or neoprene covered. Wet or dry use, 90°C conductor rating, 60°C ampacity. |
| Nominal (NOM) | The preferred size or weight that is specified or indicated for a certain cable element. |
| Non-Inductive Load and Inductive Load | A non-inductive load is a load in which the current is in phase with the voltage across the load. An inductive load is a load in which the current lags behind the voltage across the load. |
| Non-linearity | The error defined by the maximum deviation of measured output from a best fit straight line during any one calibration cycle. |
| NON-MAGNETIC MATERIAL | A material whose molecules cannot be magnetized. |
| Nonmetallic Sheathed Cable | A cable assembly consisting of individually insulated conductors, jacketed, or sheathed, with a nonmetallic material. The material usually consists of PVC or polyehylene. |
| Non-Renewable Fuse | An enlosed fuse with a link which cannot be replaced after operation. This fuse conatins an arc quenching filter. |
| Non-repeatability | The error defined by the ability of a transducer to reproduce an output signal when the same pressure value is applied to it consecutively, under the same conditions, and in the same direction. |
| Nordel® | DuPont trademark for FPDM synthetic rubber. |
| Normally Closed (N.C.) | Current flow through the switching device is possible only when the device is in the off-state or energized. |
| Normally Closed (N.C.) Output | The sensor opens a circuit to the load when a target is detected. |
| Normally Open (N.O.) | Current flow through the device is not possible when the device is deenergized (turned-off). |
| Normally Open (N.O.) Output | The sensor closes a circuit to the load when a target is detected. |
| NORMALLY OPEN and NORMALLY CLOSED | These terms refer to the position taken by the contacts in a magnetically operated switching device, such as a relay, when the operating magnet is de. energized. |
| NPN (sinking) | A transistor having an n-type semiconductor as its emitter and collector and a p-type semiconductor as its base. |
| NRHW | Moisture and heat-resistant rubber insulation with neoprene jacket for use in ducts. Dry and wet locations, 600V, 75°C. Also RHWN. |
| OAW | Overall width. |
| OD | Outside diameter |
| OFF-delay | Allows an output signal to continue for a present time beyond the end of the input signal. |
| OHM | Unit of electrical resistance. |
| Ohm | A unit of electrical resistance, the resistance of a circuit in which a potential difference of one volt produces a current of one ampere. |
| OHM | The standard unit for measuring resistance to flow of an electrical current. Every electrical conductor offers resistance to the flow of current, just as a tube through which water flows offers resistance to the current of water. One ohm is the amount of resistance that limits current flow to one ampere in a circuit with one volt of electrical pressure. |
| OHMMETER | An instrument for measuring the resistance in ohms of an electrical circuit. |
| Ohm-pound/mile | A unit of weight resistivity expressing the resistance of a wire one pound in weight and one mile in length. |
| Ohm’s Law | The relationship between voltage, current and resistance, expressed by the equation E=IR, where E is the voltage in volts, I is the current in amperes, and R is the resistance in ohms. |
| OHM’S LAW | Ohm’s Law states that when an electric current is flowing through a conductor, such as a wire, the intensity of the current (in amperes) equals the electromotive force (volts) driving it, divided by the resistance of the conductor. The flow is in proportion to the electromotive force, or voltage, as long as the resistance remains the same. |
| Oil Circuit Breaker | A circuit breaker arranged to interrupt one or more electric circuits in oil. |
| Oil Switch | A switch arranged to interrupt one or more electric circuits in oil. |
| ON-delay | Allows an output signal to delay for a preset time after the start of the input signal. |
| One Time Fuses | Generic term used to describe a Class H nonrenewable cartridge fuse, with a single element. |
| One-Shot | An output signal produced for a preset time that is indendent of the duration of the input signal. It may begin at the start of the input signal or be delayed. |
| Open Collector | NPN and PNP devices that have no other components connected to the collector portion of the device. An external load connected to an open collector output provides similar operation to a SPST mechanical relay. |
| OPEN OR OPEN CIRCUIT | An open or open circuit occurs when a circuit is broken, such as by a broken wire or open switch, interrupting the flow of current through the circuit. It is analogous to a closed valve in a water system. |
| Open System Architecture | International standards for data network which allows multi-vendor/multi-product applications. |
| Operating Distance | The distance from the sensing face to the plane of the target’s path once it reaches the operating point. |
| Operating Point | The point at which a target is sensed as it approaches the sensing field of the sensor. Also called “trip point.” |
| Operating Range | The range in the x,y,z plane that will cause the switch to operate when a detectable object is in it. |
| Operating Temperature Range | The range of ambient temperatures within which the transducer may be operated and not suffer any damage or permanent change in specifications. |
| Operation Mode | Two possible modes that will cause the switch to operate and produce an output. Light-on or Dark-on mode. |
| OPERATIONAL AMPLIFIER | A high – voltage gain, low – power, linear amplifying circuit device used to add, subtract, average, etc. |
| Optical Fiber | A thin filament of glass or plastic capable of carrying information in the form of light. |
| Organic Fiber | A fiber derived or composed of matter originating in plant or animal life or composed of chemicals of hydrocarbon origin, either natural or synthetic. |
| Oscilloscope | Test instrument for showing visually the changes in a varying current by displaying the corresponding voltage wave form on a fluorescent screen. |
| OSHA | Occupational Safety and Health Act of 1970 administered by the U.S. Dept. of Labor which establishes standards and safety requirements which all businesses must meet. (Occupational Safety and Health Administration) part of the U.S. Department of Labor responsible for assuring that employers provide safe and healthful working conditions and equipment for employees, and that employees properly avail themselves of these conditions. |
| Outlet | A fixed connection where horizontal cable terminates and work area equipment can be connected. A point on the wiring system at which current is taken to supply utilization equipment. |
| Output | The electrical signal which is produced by an applied input to the transducer. |
| Output Transistor | A semiconductor device used to provide ON/OFF switching of external holds. |
| Overcurrent | Any current in excess of conductor ampacity or in excess of equipment continuous current rating. |
| Overlap | The amount the trailing edge laps over the leading edge of a spiral tape wrap. |
| Overload | The operation of conductors or equipment a current that will cause damage if allowed to persist. |
| OVERRUNNING CLUTCH | One type of flywheelengaging member in a starting motor. |
| Oversized Wall Plate | A wall plate with length and width dimensions greater then standard wall plates. |
| Oxidation | The process of uniting a compound with oxygen, usually resulting in an unwanted surface degradation of the material or compound. |
| Ozone | Form of oxygen produced by discharge of electricity into the air. |
| Ozone Test | Exposure of material to a high concentration of ozone to give an accelerated indication of oxidation in normal environments and in proximity to ozone producing apparatus. |
| P | Two or more rubber-insulated stranded conductors with cotton braid over each. Reinforced with overall covering of cotton braid over rubber filler. For pendant or portable use in damp locations. 300V-600V |
| PAC | Preassembled aerial cable |
| Package | An object used for accumulating and dispensing wire and cable for further processing or end use. A few of the more popular types of packages are reels, bobbins, spools, stems, and coils. |
| Pair | Two wires, twisted together with a reciprocal color code. |
| Paracril | Uniroyal tradename for nitrile rubber/PVC blend usually used for jacketing. (See EZC and NBR/PVC) |
| PARALLEL CIRCUIT | A circuit in which the circuit components are arranged in branches so that there is a separate path to each unit along which electrical current can flow. |
| Passive Infrared | (P.I.R.) Typically this term is used in reference to detecting infrared. A P.I.R. detector functions as a receiver of infrared emitted from a transmitter, such as the human body. |
| Paste Extrude | An extrusion method whereby the extrudable material is in a fine powder form mixed with a lubricant and is forced through a die of given size, without heat, as opposed to melt extrude. |
| Patch Cord | A length of cable, with connectors on the ends, used to join telecommunications links at a cross-connect. |
| Patch Panel | Connecting hardware that can be accessed with patch cords to form cross-connection (usually located in a telecommunications closet) used to modify, reconfigure, or administer communications networks. |
| Pay-Off | The process of feeding a cable or wire from a bobbin, reel, or other packages. Also a device used for paying out wire or cable into a piece of equipment or machinery. |
| PBX | (Private Branch Exchange)A telephone switching device serving a specific Customer. |
| PBX (Private Branch Exchange) | A telephone switching system serving one organization or business, which is connected to the public telephone system. |
| PCG | Portable mine cable with power, control and ground conductors. |
| PD | Rubber-insulated stranded conductors with cotton braid over each. Conductors twisted with braid overall. Light duty, dry locations on appliances. 300V |
| PDN | (Public Data Network) A network established and operated for the specific purpose of providing datat transmission services to the public. |
| Peak Current | The short duration peak current rating of a surge suppression device. |
| Peak Let-Through Current, Ip | The instantaneous value of peak current let through by a current-limiting fuse, when it operates in its current limiting range. |
| Peak Torque | Many types of loads such as reciprocation compressors have cycling torques where the amount of torque required varies depending on the position of the machine. The actual maximum torque requirement at any point is called the peak torque requirement. Peak torques are involved in things such as punch presses and other types of loads where an oscillation torque requirement occurs. |
| Peak Voltage | The maximum instantaneous voltage. |
| Percent Conductivity | The conductivity of a material expressed as a percentage of that of copper. |
| Period | The time required for the current to pass through one cycle. |
| PERMANENT MAGNET | A magnet which retains its property of magnetism for an indefinite period. |
| PG | Portable mine cables having power and ground conductors. 600V |
| 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 is the indication of the type of power supply for which the motor is designed. Two major categories exist; the single phase and three phase. There are some very spotty areas where two phase power is available but this is very insignificant. |
| Phase Control | The electronic process of chopping or turning on and off the AC line every half line cycle. It is commonly used in dimming and fan speed control applications. |
| Phase Difference: Lead and Lag | The difference in phase between two sinusoidal waves having the same period, usually expressed in electrical degrees. The voltage wave if generally taken as the reference, so in an inductive circuit the current lags the voltage, and in a capacitive circuit the current leads the voltage. |
| Phase Modifier or Phase Advancer | A machine which suppiles leading or lagging reactive volt amperes to the system to which it is connected. Phase modifiers may be either synchronous or asynchronous. |
| Phase Shift | A change in phase of a voltage or current after passing through a circuit or cable |
| Photoelectric Sensor | A light sensitive device that converts visible and infrared light waves into an electrical signal. |
| Pick | Distance between two adjacent crossover points of braid filaments. This measurement, in picks per inch, indicates completeness of coverage (the more per inch, the more complete the coverage). |
| Picofarad | One micro-microfarad. |
| PIEZO ELECTRIC DEVICE | A device made of crystalline materials, such as quartz, which bend or distort when force or pressure is exerted on them. This pressure forces the electrons to move. |
| Pilot Light | A switch with an integral lamp in the actuator which lights when the switch is in the “ON” position. |
| Pin | Denoting an electrical terminal, usually in a connector. Normally a smaller termination than a lug. |
| Pin and Sleeve | Industrial wiring devices utilizing round pin-shaped blades and tubular designed sleeve contacts. |
| Pitch Diameter | The diameter of a circle passing through the center of the conductors in any layer of a multiconductor cable. |
| PL | Two rubber-insulated, parallel-laid, lamp cords with overall cotton or rayon braid. For light duty on small appliances in dry locations. 300V |
| 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. |
| Plant Factor or Plant Capacity | The ratio of the average load to the rate capacity of the power plant. |
| Plasticizer | A chemical agent added in compounding plastics to make them softer and more flexible. |
| PLATE | A solid substance from which electrons flow. Batteries have positive plates and negative plates. |
| Plating | The application of one metal over another. |
| Plenum | A chamber which forms part of a building’s air distribution system. |
| PLSJ | All-rubber, parallel-jacketed, two-conductor, light duty cord for pendant or portable use in damp locations. |
| PLT | Same as PLSJ except thermoplastic insulation. |
| Plug | A device utilizing blades which when inserted into a receptacle establishes connection between the conductors of the attached flexible cord and the conductors connected to the receptacle. |
| Plug Fuse | A “household” type fuse with a threaded base such as an Edison-base or Type S tamperproof base. Rated 0-30 amperes, 125 volts. |
| PNA, PNW | Polyethylene-insulated control cables with nylon sheath on individual conductors. Cabled tape and polyvinyl chloride jacket. Dry or wet locations, 600V, 75°C |
| PNP (sourcing) | A junction transistor having a p-type semiconductor as its emitter and collector and an n-type semiconductor as its base. |
| PO | Two stranded copper conductors with separator and code rubber insulation and cotton braid over each. Laid parallel with cotton or rayon braid overall. For use in dry locations on small appliances. 300V-600V |
| Polar Ingredient | Any ingredient in a material or complex capable of ionization. |
| POLARITY | A collective term applied to the positive (+) and negative ( – ) ends of a magnet or electrical mechanism such as a coil or battery. |
| Polarization | A means of assuring the mating of plugs and receptacles of the same rating in only the correct position. |
| Polarized | Visible light from the emitter of a retroreflective photoelectric sensor that is filtered so as to be projected in only one plane. The receiver of a polarized unit is filtered to accept only light that is reflected perpendicular to the emitted light. Corner cube reflectors are required to properly rotate the emitted light source. |
| Pole | The term “Pole” as used in designating plugs and receptacles refers to a terminal to which a circuit conductor (always current carrying) is connected. In switches, the number of poles indicates the number of conductors being controlled. |
| POLE | One or two points of a magnet at which its magnetic attraction is concentrated. |
| POLE SHOES | Iron blocks fastened to the inside of a generator or motor housing around which the field or stator coils are wound. The pole shoes may be permanent or electro-magnets. |
| Polychloroprene | Chemical name for Neoprene. A rubber-like compound used for jacketing where wire and cable will be subject to rough usage, moisture, oil, greases, solvents and chemicals. May also be used as low insulating material. |
| Polymer | A material having molecules of high molecular weight formed by polymerization of lower molecular weight molecules. |
| Polyphase | A general term applied to any system of more than a single phase. This term is ordinarily applied to symmetrical systems. |
| POSITIVE | Designating or pertaining to a kind of electricity. Specifically, an atom which loses negative electrons and is positively charged. |
| POSJ | All-rubber, parallel, light duty rip-cord for use on lamps and small appliances. 300V, 60°C |
| POSJX | All-rubber, parallel, #20 A.W.G. rip-cord for use on lamps, clocks and Christmas tees. 125V |
| POT | Thermoplastic, parallel, light duty rip-cord. 300V, 60°C to 105°C |
| Potential Transformer | A transformer designed for shunt or parallel connection in its primary circuit, with the ratio of transformation appearing as a ratio of potential differences. |
| Potentiometer | (POT) A variable resistor, when used in a phase control it adjusts the light intensity. |
| POTENTIOMETER | A variable resistor used as a voltage divider. |
| Potting | The sealing of a cable termination or other component with a liquid, which thermosets into an elastometer or solid compound to exclude moisture. |
| Power | Rate or work, equals work divided by time. |
| Power Cable | A cable of various sizes, various construction and insulation. Used to supply power to a variety of types of equipment. |
| Power Consumption | Maximum amount of power required to properly operate the device. |
| Power Factor | The ratio of the power to the effective values of the electromotive force multiplied by the effective value of current in volts and amperes respectively. The cosine of the angle between voltage applied and the current resulting. Percent power factor is a measure of a particular motor’s requirements for magnetizing amperage. |
| Power in an Alternating-Current Circuit | The product of the voltage, current and the cosine of the phase difference between them. Expressed in watts. |
| POWER SWITCH TRANSISTOR | The part responsible for switching off the primary circuit that causes high voltage induction in the secondary winding in an electronic ignition system. |
| POWERFLEX 90® POWER CABLE | A premium 600/200 volt portable power cable. |
| Powersum | A test method for four-pair cable which compares the sum of the pair-to-pair crosstalk from three pairs to the fourth pair. |
| POXT | Same as POT, but #20 A.W.G. for clock and Christmas tree use. 125V |
| Premises Wiring | The technology of wiring buildings and equipment for data, telephone, video and other electrical/electronic functions. |
| Premises Wiring System | The complete wiring system, on a user premises, used for the transmission of voice, data, and video. |
| Preset | The ability of a dimmer or fan speed control to remember a desired level of output. |
| Pressure Range | The minimum and maximum pressure limits over which a specified transducer is designed to operate. |
| Primary | The windings of a transformer which receiver every from the supply circuit. |
| Primary Insulation | The layer of material which is designed to do the electrical insulating, usually the first layer of material applied over the conductor. |
| PRIMARY SPEED SENSOR | An engine speed sensor located inside the actuator housing on the back of the injection pump. |
| PRINCIPLE OF TURNING FORCE | Explains how magnetic force acts on a current – carrying conductor to create movement of an armature, such as in an electric motor. |
| PRINTED CIRCUIT BOARD | A device used to hold integrated circuit components in place and provide current paths from component to component. Copper pathways are etched into the board with acid. |
| Proof Pressure (Overload Pressure) | The maximum pressure that can be applied to the sensing element of a transducer without causing permanent change in the output specifications. |
| Propagation Constant | A complex quantity characteristic of a radio frequency transmission line which indicates the effect of the line on the transmitted wave. The real part indicates the attenuation and the imaginary part the phase shift. |
| Propogation Delay | Time between when a signal is transmitted and when it is received at the opposite end of the cable. |
| PROTON | A particle which, together with the neutron constitutes the nucleus of an atom. It exhibits a positive charge of electricity. |
| Prototype | Original design or first operating model. |
| Proximity Effect | The phenomena of nonuniform current distribution over the cross-section of a conductor caused by the variation of the current in an adjoining conductor. |
| PS | Thermostat cable with solid conductors, individual rubber insulation and cotton braid. Twisted, rubber jacket and cotton braid overall. |
| PSI | Pound per square inch. |
| PTFE | Polytetrafluoroethylene, a synthetic fluoropolymer of tetrafluoroethylene (TFE). A thermoplastic polymer known for high strength, toughness and flexibility. |
| Pull Chain Lampholder | An incandescent lampholder containing a switching mechanism that is actuated by pulling downward on a beaded chain. |
| Pull Out Torque | Also known as breakdown torque, this is the maximum amount of torque that is available from the motor shaft when the motor is operating at full voltage and is running at full speed. The load is then increased until the maximum point is reached. |
| Pull Switch | A switch with an actuator mechanism operated by a downward or outward pull |
| Pull Up Torque | The lowest point on the torque speed curve for a motor that is accelerating a load up to full speed is called the pull up torque. Some motor designs do not have a value of pull up torque because the lowest point may occur at the locked rotor point. In this case pull up torque is the same as locked rotor torque. |
| Pulling Grip | A reusable wire mesh grip for pulling cable, rope or bare conductor |
| Pulling Tension | The amount of pull (foot-pounds of tension) placed on a cable during installation. |
| PULSE | A signal that is produced by a sudden ON and OFF of direct current (DC) within a circuit. |
| Pulse Cable | A cable specifically constructed to withstand and transmit repeated high voltage pulses without undue physical or electrical degradation. |
| Pulse Modulated | Light sources that are pulsed (ON/OFF) at a high frequency by an oscillator circuit. The receiver of a pulse modulated photoelectric only receives light at that frequency, thus minimizing interference from ambient light. |
| PULSE-WIDTH-MODULATED (PWM) | A digital electronic signal which consists of a pulse generated at a fixed frequency. The information transmitted by the signal is contained in the width of the pulse. The width of the pulse is changed (modulated) to indicate a corresponding change in the information being transmitted, such as throttle command. |
| Punchdown | Securing a conductor to a wiring terminal by placing the insulated conductor in the terminal groove and pushing down with a “punchdown” (impact) tool – creating an insulation displacement connection (IDC). |
| Push Back | That property of a braid or shield which allows the braid or shield to be pushed back along the cable core easily. |
| Push Through Lampholder | A lampholder having an insulated projection through its sides, which when pushed from either side, turns the lamp on or off. |
| Push/Push | A means of achieving the preset features on a rotary dimmer or fan speed control. The secondary switching mechanism is activated by pushing the knob at any preset of light or speed. |
| Put-Up | Refers to packaging of wire and cable, the term itself refers to the packaged product that is ready to be stored or shipped out. |
| Quad-Rated Wire | The name for 90°C and 105°C wire which replaces four other types of wire – CSA TEW 105°C; 90°C MTW 600V; 90°C AWM 1000V; and 105°C AWM 600V. |
| Quadruplex Cable | A cable composed of four conductors twisted together, usually three insulated and a bare neutral. |
| Quarter-Phase or Two-Phase | A term characterizing a combination of two circuits energized by alternating voltage sources which differ in phase by a quarter of a cycle, 90 degrees. |
| R | Code rubber-insulated building wire, 600V, 60°C. |
| R.M.S. | (Root Means Square) Used as an A.C. value of voltage or current. Expressed for example as 120 volts AC RMS. |
| Rated Voltage | That maximum voltage at which an electrical component can operate for extended periods without undue degradation of safety hazard. |
| Rating | The rating of an electrical device includes (1) the normal r.m.s. current which it is designed to carry, (2) the normal r.m.s. voltage of the circuit in which it is intended to operate, (3) the normal frequency of the current and the interruption (or withstand) rating of the device. |
| RCDD | (Registered Communications Distribution Designer) – Professional certification granted by BICSI. |
| RD | Rubber-insulated twin conductors, fibrous covered. |
| RDL | Rubber-insulated twin conductors, lead covered. |
| Reactance | That part of the impedance of an alternating current circuit which is due to capacitance or inductance. |
| Reactive Factor | The ratio of the reactive volt-amperes to the apparent power. |
| Reactive or Quadrature Componenet | That component of the current which is quadrature, or 90 degees out of phase, with the voltage across the circuit. |
| Reactive Volt Amperes | The product of the voltage, current and the sine of the phase difference between them. Expressed in vars. |
| Receiver | Portion of a photoelectric sensor that contains a photo sensor. |
| Receptacle | A contact device which is intended to establish electrical connection with an inserted plug. |
| RECTIFIER | A device (such as a vacuum tube, commutator, or diode) that converts alternating current into direct current. |
| Redraw | The consecutive drawing of wire through a series of dies to each a desired wire size. |
| Reel | A revolvable flanged device made of wood and/or metal which is used for winding flexible metal wire or cable. |
| Reflection Loss | That part of a signal which is lost due to reflection of power at a line discontinuity. |
| REGULATOR | A device which controls the flow of current or voltage in a circuit to a certain desired level. |
| Reinforced Sheath | The outermost covering of a cable that has a cable sheath constructed in layers with a reinforcing material, usually a braided fiber, molded in place between layers. |
| Rejection Fuse | A current-limiting fuse with high interrupting rating and with unique dimensions or mounting provisions. |
| Rejection Fuse Block | A fuse block designed to accept fuses of a specific class. |
| Relay | A device which is operative by variation in the conditions of one electric circuit to effect the operation of other devices in the same or another electric circuit. |
| RELAY | An electrical coil switch that uses a small current to control a much larger current. |
| Release Point | The point at which a sensor returns to its original state as the target leaves the sensing field. Also called “reset point.” |
| RELUCTANCE | The resistance that a magnetic circuit offers to lines of force in a magnetic field. |
| RELUCTOR | A metal cylinder, with teeth or legs, mounted on the distributor shaft in an electronic ignition system. The reluctor rotates with the distributor shaft and passes through the electromagnetic field of the sensor. |
| Renewable Fuse | An enclosed fuse the body of which can be opened and the fusible link replaced for re-sue. This fuse usually does not have a filter. |
| Repeat Accuracy | The measure of variation in operating distance between succussive operations under constant operating conditions. The measurement is often expressed as a maximum percentage of the “operating distance.” (NOTE: The target must also remain within the sensing field long enough to allow the load sufficient time to respond to the output signal of the sensor. |
| Resilient | The property of a substance to return to its original configuration after release of an applied force. |
| Resistance | The property of an electric circuit which determines for a given current the rate at which electric energy is converted into heat and has a value such that the current squared multiplied by the resistance gives the power converted. |
| RESISTANCE | The opposing or retarding force offered by a circuit or component of a circuit to the passage of electrical current through it. Resistance is measured in ohms. |
| Resistive Conductor | A conductor used for its high electric resistance characteristics. |
| Resistive Load | A device which opposes the flow of electric current. There is a voltage drop across a resistive load, which causes the device to dissapate heat. |
| RESISTOR | A device usually made of wire or carbon which presents a resistance to current flow. |
| Response Time | Time it takes for an output of a photoelectric sensor to respond to an input signal. The length of time required for an output of a transducer to rise to a specific percentage of its final value as a result of a step change in input. |
| Retroreflective | Detection method where light from the emitter is aimed at, and reflected back to the receiver, from a retroreflective target. |
| Return Loss | Noise or interference cause by impedance of a cable expressed in decibels. |
| Reverse Polarity Protection | Internal circuitry that protects a device from being ruined if proper polarity of voltages is not maintained when wiring the device. |
| RF | Fixture wire, code or latex rubber-insulation and braid over solid or stranded conductor. 60°C |
| RFH | Same as RF, but rubber or latex rubber insulation heat-resistant. 75°C |
| RFI | (Radio Frequency Interference) Electrical Noise |
| RH | Rubber-insulated, heat resistant building wire. 75°C |
| RH/RW | Rubber-insulated, heat and moisture resistant building wire. 75°C dry, 60°C wet. |
| RHD | Rubber-insulated, twin conductor, heat-resistant, fibrous covered wire. |
| RHDL | Same as RHD, except lead instead of fibrous covered. |
| Rheostat | An adjustable resistor constructed so that its resistance may be changed without opening the circuit. |
| RHEOSTAT | A resistor used for regulating a current by means of variable resistance; rheostats allow only one current path. |
| RHH | Rubber-insulated, heat-resistant building wire. 90°C |
| RHL | Same as RHH, but with lead sheath overall. |
| RHM | Rubber-insulated multiple conductors, heat-resistant and overall fibrous covered. |
| RHML | Same as RHM, but with lead cover overall. |
| RHW | Rubber-insulated building wire, heat and moisture-resistant. 75°C dry or wet. |
| Ribbon Cable | A cable consisting of two or more conductors laid parallel in one plane and held in place by some means. |
| RIGHT-HAND RULE | A method used to determine the direction a magnetic field rotates about a conductor, or to find the north pole of a magnetic field in a coil. |
| Ring | One of the two conductors or cable pair in a telephone circuit. |
| Riser | The conduit path between floors of a building. |
| RJ | Rubber-insulated and jute covered cable. |
| RJ (Registered Jack) | Telephone and data jack applications registered with FCC. |
| RJFJ | Rubber-insulated cable with flat band armor. |
| RJIJ | Rubber-insulated cable with interlock armor. |
| RL | Rubber-insulated cable with lead sheath. |
| RLJFJ | Rubber-insulated cable with lead, jute, flat band armor and overall jute overing. |
| RLJWJ | Rubber-insulated cable with lead, jute, steel wire armor and overall jute covering. |
| RM | Rubber-insulated multiple conductors with fibrous covering. |
| RML | Same as RM, but lead instead of fibrous covering. |
| Rocker Switch | A switch that is operated by a paddle type actuator such as a decorator switch. |
| Rod | The solid round metallic form of copper and aluminum which is the most effective shape from which to draw wire. |
| Romex | Non-Metallic Sheath Cable |
| Root Mean Square | The effective value of an alternating periodic voltage or current. |
| Root-Mean Square or Effective Value | The square root of the mean of the squares of the instantaneous values for one complete cycle. It is usually abbreviated r.m.s. Unless otherwise specified, the numerical value of an alternating current refers to its r.m.s. value. The r.m.s. value of a sinusoidal wave is equal to its maximum, or peak value, divided by square root of 2 |
| Rope Strand | A conductor composed of a center group of twisted strands surrounded by one or more layers of simliar groups of twisted strands. |
| Rope-Lay Cable | A concentric stranded cable designed for flexibility with its individual members made up of strands which are either concentric stranded or bunched. |
| Rotary Dimming | Is achieved through the rotation of a knob of any style to control the lighting level components. |
| Rotary Phase Converter | Converts an alternating current system of one or more phases to alternating current system of a different number of phases, but of the same frequency. |
| ROTOR | The rotating part of an electrical machine such as a generator, motor, or alternator. |
| Round Strand | A conductor composed of a center group of twisted strands surrounded by one or more layers of similiar groups of twisted strands. |
| Round Wire | A wire circular in cross section as opposed to flat, square, etc. |
| RP | Performance grade rubber insulation, 60°C. |
| RPM | Revolutions Per Minute. |
| RR | Rubber insulation, neoprene jacket. See type USE |
| RS | Integral rubber insulation and jacket on single conductor cables. |
| RTS | Reverse twist secondary. |
| RU | Rubber-insulated, latex building wire. 60°C |
| RUH | Same as RU, but heat-resistant. 75°C |
| Rupture | In the breaking strength or tensile strength tests the point at which a material physically comes apart as opposed to yield strength, elongation, etc. |
| RUW | Same as RU, but moisture-resistant. 60°C |
| RW | Rubber-insulated building wire. Moisture-resistant. 60°C |
| RWS | Same as RW, but synthetic rubber. |
| S | Heavy duty, rubber-insulated, portable cord. Stranded copper conductors with separator and individual rubber insulation. Two or more color coded conductors cabled with filler, wrapped with separator and rubber jacketed overall. 600V |
| SA | Silicone rubber insulation, asbestos or glass braid, for use in dry locations. Maximum operating temperature for special applications, 125°C. |
| Sag (conductor) | The vertical distance between a suspended conductor and an imaginary straight-line connecting the points of suspension. Sag may be measured at the mid point between the suspensions, the lowest point of the conductor or at any specified point. |
| SB | Slow burning wire. Three cotton braids, impregnated. 90°C |
| SBR | Rubber co-polymer of styrene and butadiene. |
| SCR | Silicon Controlled Rectifier. Semiconductor used in AC two-wire devices to provide voltage to the device and to switch in-line loads. |
| Screw Extruder | A machine which accpets solid particles (pellot or powder) or liquid (molten) feed; melts and conveys it through a surrounding barrell by means of a rotating screw and pumps it, under pressure, through a die. |
| SD | Service drop cable. Two code-rubber-insulated conductors, tape, laid parallel with neutral conductor concentric turnover. Tape and braid overall. Also round construction. |
| SDC | Self Damping Conductors |
| SDN | Small diameter multi-conductor control cable with neoprene jacket and nylon sheath over polyethylene insulation. |
| SDT/TC | Thermo plastic 90°C tray cable. |
| SE | Above ground service entrance cable, not protected against mechanical abuse. Flame-retardant, moisture-resistant covering. Over neoprene sheath. 60°C-75°C |
| SEA | Service entrance cable, steel-armored under outer braid, one or two rubber-insulated conductors with neutral conductor served concentrically, moisture-resistant tape, weatherproof-braid finish. 300V, 75°C |
| Sealed Gauge Pressure (PSIS) | A measure of pressure reference to atmospheric pressure. |
| Secondary | The windings which receive the energy by induction from the primary. |
| Sectional Wall Plate | Individual section wall plates with different openings that can be field assembled into a custom multi-gang wall plate. |
| Sector Cable | A multicore cable in which the cross section of each conductor is substantially a section of a circle, an ellipse (oval), or a figure intermediate between them; when cabled, contributes to a smaller overall diameter. |
| SELF-INDUCTION | Voltage which occurs in a coil when there is a change of current. |
| Self-Supporting Cable | Made with a steel support strand capable of supporting its own weight across spans. |
| Semi-Conducting | A non-conducting material made slightly conducting by the addition of a conducting material such as carbon. |
| SEMICONDUCTOR | An element which has four electrons in the outer ring of its atoms. Silicon and germanium are examples. These elements are neither good conductors nor good insulators. Semiconductors are used to make diodes, transistors, and integrated circuits. |
| Semiconductor Fuse | An extremely fast-acting fuse intended for the protection of power semiconductors. Sometimes referred to as a rectifier use. |
| Semi-Rigid | A cable containing a flexible inner core and a relatively inflexible sheathing material, such as a metallic tube, but which can be bent for coiling or spooling and placing in a duct or cable run. |
| SENDING UNIT | A device, usually located in some part of an engine, to transmit information to a gauge on an instrument panel. |
| Sensing Distance | The maximum distance at which under specifications, a photoelectric sensor can detect a target. |
| Sensing Range | The maximum operating range at which the sensor will reliably detect a standard target under conditions of nominal voltage and temperature. |
| Sensor | A device that detects, and then responds to an external stimulus or change. |
| SENSOR | A small coil of fine wire in the distributor on electronic ignition systems. The sensor develops an electromagnetic field that is sensitive to the presence of metal. In monitors and controllers, they sense operations of machines and relay the information to a console. |
| SEPARATOR | Any of several substances used to keep one substance from another. In batteries a separator separates the positive plates from the negative plates. |
| Series | An adapter wired in series to a fexible cord containing an in-line switch which is used to control electrical equipment plugged into the adapter. |
| SERIES CIRCUIT | A circuit in which the parts are connected end to end, positive pole to negative pole, so that only one path is provided for current flow. |
| Series Resistance | Any sum of resistances installed in sequential order within one circuit. |
| SERIES-PARALLEL CIRCUIT | A circuit in which some of the circuit components are connected in series and others are connected in parallel. |
| Serve | Any filament or group of filaments, such as wires or fibres helically wound around a central core. |
| Service Factor Amps | This is the amount of current the motor will draw when it is subjected to a percentage of overload equal to the service factor on the nameplate of the motor. For example, many motors will have a service factor of 1.15, meaning that the motor can handle a 15% overload. The service factor amperage is the amount of current that the motor will draw under the service factor load condition. |
| Service Loop | The slack which should be left in the cable at the communications outlet to accommodate future needs. |
| SEU | Same as SEA, but not armored. |
| SEW,SEWF | Silicone Rubber insulated equipment wire (C.S.A.). |
| SF | Silicone rubber insulated fixture wire, solid or 7 strand conductor. 200°C |
| SFF | Same as SF, except flexible stranding. 150°C |
| SG | Same as SW except with ground wires (C.S.A.). Specific Gravity |
| SGO | Same as SWO except with ground wires (C.S.A.). |
| SH-A | Portable mine power cable, three or four individually shielded conductors. 5000V |
| SH-B | Same as SH-A, except shield is overall. |
| SH-C | Same as SH-B, but with grounding conductors. |
| SH-D | Same as SH-A, but with grounding conductors. |
| Sheath | The material, usually an extruded plastic or elastomer, applied outermost to a wire or cable. Very often referred to as a jacket. |
| SHFS | Polyvinyl-insulated with felted-asbestos, flame-proof cotton or rayon braid. Navy switch-board wire. 600V |
| Shield | In cables, that metallic layer applied over the dielectric or group of dielectrics, composed of woven braided, or served wires, foil wrap or tubular metallic construction to prevent elecrostatic or electromagnetic interference between the enclosed wires and external fields. |
| Shielded Cable | Usually concerning a high voltage power cable 5000V and above enclosed in a non-magnetic conducting envelope, so constructed that substantially every point on the insulation is at ground potential or some pre-determined potential with respect to the ground. Can apply to multiple conductor cable in which each single conductor is shielded or to a multiple conductor cable where the overall assembly is shielded. |
| SHORT (OR SHORT CIRCUIT) | This occurs when one part of a circuit comes in contact with another part of the same circuit, diverting the flow of current from its desired path. |
| Short Circuit | Loads which occur during fault conditions and are characterized by very heavy current flow. Can be classified as an overcurrent which exceeds the normal full load current of a circuit. Also characteristic of this type of overcurrent is that it does not leave the normal current carrying path of the circuit-that is, it flows from the source through the conductors, through the load, back through the conductors, to the source again. |
| Short Circuit Protection | Internal circuitry which protects the photoelectric sensor in the event that the load becomes shorted. |
| Short Circuit Rating | The maximum short circuit current of an electrical component can sustain without the occurence of excessive damage when protected with an overcurrent protective device. |
| Short-Time Rating | The maximum constant load that can be carried for a apecified time without exceeding established temperature rise limitations under prescribed conditions. |
| Shunt | A device used to divert part of an electric current. |
| SHUNT | A conductor joining two points in a circuit so as to form a parallel circuit through which a portion of the current may pass. |
| SIC | Specific inductive capacity. Same as dialectric constant. |
| Signal | An electric current used to convey information either digital, analog, audio, or video. |
| Signal Conditioning | To process the form or mode of a signal so as to make it electrically compatible with a given device. |
| Single Mode Fiber | An optical fiber which allows only one mode to propogate and which is generally used for long distance telephone transmission. |
| Single Phasing | That condition which occurs when one phase of a three phase system opens, either in a low voltage (secondary) or high voltage (primary) distribution system. Primary or secondary single phasing can be caused by any number of events. This condition results in unbalanced currents in polyphase motors and unless protective measures are taken, causes overheating and failure. |
| Single Pole Switch | (single-pole single-throw) A switch that makes or breaks the connection of one conductor and controls one load from one location. |
| Single Receptacle | A receptacle that accepts only one plug. |
| Single Weave | A wire mesh grip woven with single strands of wire material |
| Single-phase circuit | An AC circuit consisting of two or three intentionally interrelated conductors. |
| Sinter | To thermally cure or treat a material. |
| SIS | Indicates single conductor having synthetic thermosetting insulation of heat-resistant, moisture-resistant, flame-retardant grade. Also made with chemically cross linked polyethylene insulation. Used for switchboard wiring only 90°C. |
| Six-Phase | A term characterizing the combination of six circuits energized by alternating e.m.f.’s which differ in phase by one-sixth of a cycle; i.e. 60 degrees. |
| SJ | Junior hard service, rubber-insulated pendant or portable cord. Same construction as type S, but 300V. Jacket thickness different. |
| SJO | Same as SJ, but neoprene, oi-resistant compound outer jacket. Can also be made “water-resistant.” 300V, 60°C |
| SJOO | Same as SJO but with oil-resistant insulation as well as an oil-resistant jacket. |
| SJT | Junior hard service thermoplastic or rubber insulated conductors with overall thermoplastic jacket. 300V, 60°C to 105°C |
| SJTO | Same as SJT but oil-resistant thermoplastic outer jacket. 60°C |
| SJTOO | Same as SJTO but with oil-resistant insulation. |
| Skin Effect | In an alternating current system, a phenomenon that occurs at increased frequencies causing an increase in resistance of the conductor leaving the outer skin to carry most of the current. The phenomenon increases in intensity the higher the frequency. |
| Skived Tape | Tape shaved in a thin layer from a cylindrical block of material. |
| SL | Single-conductor paper-lead cables twisted together, without overall covering. (same as ML) |
| Slant Symbol | (/) As used in wiring device ratings, indicates that two or more voltage potentials can be used. |
| Sleet-Proof | Apparatus is designated as sleet-proof when so constructed or protected that the accumulation of sleet will not interfere with its successful operations. |
| Slide Dimming | Is achieved through the linear movement up and down or horizontal of a slide mechanism to control the lighting level. |
| Slide Switch | A switch having a sliding actuating member which makes or breaks the sitch contact mechanism. |
| Slimline-Single Pin | A fluorescent lampholder having a single pin contact and accepting fluroescent lamps of the T-8 or T-12 types, 1″ or 1 1/2″ in diameter and in a smaller version the T-6 type, 3/4″ in diameter. |
| Slip | Slip is used in two forms. One is the slip RPM which is the difference between the synchronous speed and the full load speed. When this slip RPM is expressed as a percentage of the synchronous speed, then it is called percent slip or just “slip.” Most standard motors run with a full load slip of 2% to 5%. |
| SLIP RING | In a generator, motor, or alternator, one of two or more continuous conducting rings from which brushes take, or deliver to, current. |
| Snap-In Lampholder | A special type of incandescent lampholder supplied with assembled side spring clips which snap into a hole cut in a flat panel, securing the lampholder in place without additional fastening means. |
| SNM | Shielded non-metallic sheathed cable. |
| SO | Hard service cord, same construction as type S except oil-resistant neoprene jacket. 600V, 60°C to 90°C |
| SOLENOID | A tubular coil used for producing a magnetic field. A solenoid usually performs some type of mechanical work. |
| Solid Conductor | A solid conductor is a conductor consisting of a single wire. |
| Solid State | A device, circuit or system whose operation is dependent upon any combination of optical, electrical, or magnetic phenomena within a solid. Generally referred to as having an infinite life and no moving parts. |
| SOLID-STATE CIRCUITS | Electronic (integrated) circuits which utilize semiconductor devices such as transistors, diodes and silicon controlled rectifiers. |
| SOO | Same as SO but with oil-resistant insulation. |
| SOW | Water resistant neoprene jacketed portable cord (C.S.A.). |
| SP-1 | All rubber, parallel-jacketed, two-conductor light duty cord for pendant or portable use in damp locations. 300V |
| SP-2 | Same as SP-1, but heavier construction, with or without third conductor for grounding purposes. 300V |
| SP-3 | Same as SP-2, but heavier construction for refrigerators or room air conditioners. 300V |
| Spacer Cable | A distribution cable designed to be used in conjunction with insulating spacers which maintain conductor spacing in overhead line installations. This cable is considered uninsulated and installed likewise, but the covering on the conductors does allow for conductor close proximity and reduce faults due to the touching of tree limbs. |
| Span (Full-Scale Output for FSO) | The algebraic difference in the electrical output when the maximum and minimum pressure is applied to the input. |
| SPARK PLUGS | Devices which ignite the fuel by a spark in a spark – ignition engine. |
| Spark Test | A test designed to locate pin-holes in an insulated wire by application of an electrical potential across the material for a very short period of time while the wire is drawn through an electrode field. |
| SPC | Submersible pump cable. |
| Special Purpose Fuses | Fuses with special performance characteristics or rating intended to protect equipment or components under specified conditions. |
| Specific Gravity | The ratio of the weight of any volume of substance to a weight of an equal volume of some substance taken as a standard, usually water for liquids and hydrogen for gas. |
| SPECIFIC GRAVITY | The ratio of a weight of any volume of a substance to the weight of an equal volume of some substance taken as a standard, usually water for solids and liquids. When a battery electrolyte is tested the result is the specific gravity of the electrolyte. |
| Spiral Wrap | A term given to describe the helical wrap of a tape or thread over a core. |
| Splash-Proof | An open apparatus in which the ventilation openings are so constructed that drops of liquid or solid particles coming toward it at any angle up to 100° downward from vertical cannot enter directly or by running along a surface. |
| Split Circuit | A duplex receptacle that can be wired for two separate circuits. |
| Split Mesh | A wire mesh grip separated at one row along the wire mesh axis utilizing an additional lace or rods to weave closed around cable. |
| SPRAG CLUTCH DRIVE | A type of flywheel engaging device for a starting motor. |
| SPT-1 | Same as SP-1, except all-thermoplastic. 300V. With or without 3rd conductor for grounding. |
| SPT-2 | Same as SP-2, except all-thermoplastic. 300V. With or without 3rd conductor for grounding. |
| SPT-3 | Same as SP-3, except all-thermoplastic. 300V. With or without 3rd conductor for grounding. |
| Square Mil | The area of a square one mil by one mil. |
| SR | Silicone rubber control cable. 600V, 125°C |
| SR-AW | Flexible, nickel-plated copper conductor, silicone rubber insulation, glass braid. 600V, 200°C |
| SR-C | Solid copper conductor, silicone rubber insulation, glass braid. 600V, 125°C |
| SRD | Portable range or dryer cable. Three or four rubber-insulated conductors with rubber or neoprene jacket, flat or round construction. 300V, 60°C |
| SRDT | Same as SRD, except all-thermoplastic with a maximum temperature of 90°C. |
| SR-H | Silicone rubber-insulated, asbestos braid. 500V, 125°C |
| ST | Hard service cord, jacketed, same as type S except all-plastic construction. 600V, 60°C to 105°C |
| Stability | The output state of the photoelectric is either stably ON, ustable, or stably OFF. Unstable outputs cause the system to perform irratically. Unstable output occurs when the amount of light incident on the receiver is near the trigger level of the device. The ability of a transducer to maintain all of its performance specifications throughout its life. |
| Standard Target | An object used to determine sensing range. This is normally a square mild steel plate 1mm thick with the length of each side equal to the diameter of the sensing face or 3 times the nominal sensing distance of the sensor. |
| Star Wiring | Called Star Topology and Home Run, a method of cabling each telecommunications outlet directly to the horizontal cross-connect in the telecommunications closet with an individual pair of cables. |
| STARTER MOTOR | A device that converts electrical energy from the battery into mechanical energy that turns an engine over for starting. |
| Starting Torque | The amount of torque the motor produces when it is energized at full voltage and with the shaft locked in place. This value is frequently expressed as “locked rotor torque.” It is the amount of torque available when powere is applied to break the load away and start accelerating it up to speed. |
| STATOR | The stationary part of an alternator in which another part (the rotor) revolves. |
| STO | Same as ST but with oil-resistant thermoplastic outer jacket. 600V, 60°C to 105°C |
| STOO | Same as STO but with oil-resistant insulation. |
| STORAGE BATTERY | A group of electrochemical cells connected together to generate electrical energy. It stores the energy in a chemical form. |
| Straight Blade | A plug, connector, receptacle, flanged inlet or flanged outlet providing no locking features. |
| Strain Relief Grip | A wire mesh grip used to relieve strain or stress at the transition point between relatively flexible cable or conduit and the rigid connection point. |
| Strand | A single unisulated wire. |
| Strand Lay | The distance of advance of one strand of a spirally stranded conductor, in one turn, measured axially. |
| Stranded | A number of solid wires twisted together to form a flexible conductor. |
| Stranded Conductor | A stranded conductor is a conductor composed of a group of wires, or of any combination of groups of wires. |
| Strap Dimmer/Fan Speed Control | Any dimmer or fan speed control that will fit into a traditional NEMA standard switch box, without and external heat sink. |
| Submersible | Apparatus is designated as submersible when so constructed that it operates successfully in water under specified |
| SULFATION | The formation of hard crystals of lead sulfate on battery plates. The battery is then ‘sulfated.’ |
| Supply Voltage | The nominal voltage, or voltage range, at which the photoelectric sensor is designed to be operated continuously. |
| Support Grip | A wire mesh grip used for permanent or temporary support of a length of cable. |
| Suppressed Voltage | The amount of voltage allowed to pass through a surge suppression device to the equipment connected to the device. |
| Suppressed Voltage Rating | Determinedd by UL when specific current and voltage is applied to a surge suppression device. For permanent devices UL tests at 3000A, 6000V while portable devices are tested at 500A, 6000V. |
| Surface Lampholder | A lampholder of any type intended for mounting on a flat or plane surface. |
| Surface Mounted | A device intended to be installed on the surface a wall, panel, or equipment. |
| Surface Resistivity | The surface resistivity of a material is the ratio of the potential gradient parallel to the current along its surface to the current per unit width of the surface, usually expressed in ohms. (Note: Surface resistivity of a material is numerically equal to the surface resistance between two electrodes forming opposite sides of a square, the square size being immaterial.) |
| Surge-Supression | The use of a device containing electronic components which limits peak voltage to a pre determined value when voltage spikes or surges appear on the connected line. |
| SV | Vacuum cleaner cord, two or three-conductor, rubber-insulated. Overall rubber jacket. For light duty in damp locations. 300V, 60°C |
| SVO | Same as SV except neoprene jacket. 300V, 60°C |
| SVT | Same as SV except all-plastic construction. With or without third conductor for grounding purposes only. 300V, 60°C to 90°C |
| SVTO | Same as SVT except with oil-resistant thermoplastic jacket. 60°C |
| SW | Rubber jacketed power supply cable (8AWG to 2AWG) C.S.A. 600 Volt. |
| Switch | A device for making, breaking or changing the connections in an electric circuit. |
| SWITCH | A device which opens or closes electrical pathways in an electrical circuit. |
| Switchboard Wire | Chemically cross-linked polyethylene or asbestos insulated wire resistant to heat, flame, and corrosive vapor. |
| SWO | Same as SW except neoprene jacketed (C.S.A.). |
| SWT | Plastic jacketed power supply cable (8AWG to 2AWG) 600V (C.S.A.). |
| SYNCHROGRAPH | An all – purpose distributor tester. |
| Synchronous Converter or Rotary Converter | Converts an alternating current to a direct current. |
| Synchronous Motor | An alternating current motor which operates at the speed of rotation of the magnetic flux. |
| Synchrounous Speed | This is the speed at which the magnetic field within the motor is rotating. It is also approximately the speed that the motor will run under no load conditions. For example, a 4 pole motor running on 60 cycles would have a magnetic field speed of 1800 RPM. The no load speed of that motor shaft would be very close to 1800 RPM. The difference between the synchronous speed and the full load speed is called the slip RPM of the motor. |
| T | Thermoplastic vinyl, building wire. 60°C |
| TA | Switchboard wire, thermoplastic and asbestos insulation. 90°C |
| TAA | Flexible nickel or nickel-clad copper, PTFE tape, felted asbestos, asbestos braid. 200°C |
| TACHOMETER | An instrument for measuring rotary speed; usually revolutions per minute. |
| Take-Up | The process of accumulating wire or cable onto a reel, bobbin, or some other type of package. Also refers to the device utilized for pulling wire or cable through a piece of equipment or machine. |
| Tamper Resistant | A receptacle which by its construction limits improper access to its energized contacts. |
| Tandem | A wall plate in which individual gangs are arranged vertically one above the other. |
| 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 as ground. |
| Tape Wrap | A term denoting a spirally or longitudinally applied tape material wrapped around the wire, either insulated or uninsulated, used as an insulation or mechanical barrier. |
| Target | The object to be detected. |
| Tarnish | A term used to describe a discolored or stained conductor or shield wire caused by exposure to the atmosphere. |
| TAS | Shielded thermoplastic appliance wire. |
| TBS | Switchboard wire, thermoplastic insulation, flame-proof cotton braid. 600V, 90°C |
| TBWP | Three cotton braids, weatherproof saturated. No voltage rating. |
| TC | Tray cable Art 340 NEC |
| Tear Test | A test to determine the tear strength of an insulating material. |
| Temperature Coefficient of Resistivity | The amount of resistance change of a material per degree of temperature rise. |
| Temperature Stress | The maximum stress which can be applied to a material at a given temperature without physical deformation. |
| TEMPORARY MAGNET | A magnet which loses its property of magnetism quickly unless forces act to re – magnetize it. |
| Tensile Strength | A term denoting the greatest longitudinal tensile stress a substance can bear without tearing apart or rupturing. |
| Tensile Stress | Torce per unit cross-sectional area applied to elongate a material. |
| Tension Set | The condition when a plastic material show permanent deformation cause by stress, after the stress is removed. |
| Terminal | A terminal is a fixed location on a wiring device where a conductor is intended to be connected. |
| Test Reports | The permanent records made by a wire manufacturer of the test performed on a batch of wire to a specification. |
| TEW | Canadian Standards Association type appliance wires. Solid or stranded single conductor, plastic-insulated. 600V, 105°C |
| TF | Fixture wire, thermoplastic-covered solid or 7 strands. 60°C |
| TFE | Tetrafluoroethylene (also see PTFE) |
| TFF | Same as TF but flexible standing. 60°C |
| TFFN | Same as TFF but with nylon sheath |
| TG | Flexible nickel or nickel-clad copper conductor, PTFE tape, glass braid. 200°C |
| TGS | Solid or flexible copper, nickel-clad iron or copper, or nickel conductor. PTFE tape, silicone glass braid. 600V, 250°C |
| Thermal Aging | Exposure to a given thermal condition or a programmed series of conditions for prescribed periods of time. |
| Thermal Alloying | The act of uniting two different metals to make one common metal by the use of heat. |
| Thermal Effect on Span | The error defined by the change in sensitivity due to a change in ambient temperature within the compensated temperature range. |
| Thermal Effect on Zero | The error defined by the maximum deviations from the zero due to changes in ambient temperature, within the compensated temperature range and no pressure applied. |
| Thermal element | A metallic or nonmetallic fusible material that is part of a thermal cutoff and is responsive to temperature by a change of state at the temperature for which it is calibrated. |
| Thermal Expansion | The expansion of a material when subjected to heat. |
| Thermal Rating | The maximum and/or minimum temperature at which a material will perform its function without undue degradation. |
| Thermal Resistance | That change in the electrical resistance of a material when subjected to heat. Resistance to heat flow from conductors to outer surface of insulation or sheath in a wire or cable. |
| Thermal Resistivity | Thermal resistance of a unit cube of material. |
| 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. |
| Thermal-Magnetic Circuit Breaker | A circuit breaker which has the overcurrent and tripping means of the thermal type, the mangetic type or a combination of both. |
| THERMISTOR | A temperature – compensated resistor. The degree of its resistance varies with the temperature. In some regulators, it controls a Zener diode so that a higher system voltage is produced in cold weather, when needed. |
| Thermocouple | A device consisting of two metals usually in wire form joined in two places. If a temperature difference exists between the junctions, a voltage is generated which can be calibrated to indicate temperature. |
| Thermocouple Lead Wire | Similar to thermocouple wire except the degree of accuracy in temperature measurements is not as high and it is used to transmit thermocouple information to remote indicators. |
| Thermocouple Wire | A two conductor cable, each conductor employing a dissimilar metal, made up specifically for temperature measurements. |
| Thermoplastic | Insulation that will resoften and distort from its formed shape by heating above a critical temperature peculiar to the material. |
| Thermoplastic Elastomer | Used for insulation and jacketing compound for portable cords with the following U.L. designations. SE, SEO, SRDE, SPE, SJE, SJEO. |
| Thermosetting | Term describing insulation that will not resoften or distort from its formed shape by heating until a destructive temperature is reached. |
| Thermostat | An automatic control actuated by temperature change to maintain temperatures between predetermined limits. |
| THHN | 90°C 600V nylon jacketed building wire |
| Three Postition Center “OFF” | A two circuit, three position switch either the maintained or momentary type, in which the OFF position is indicated by the centered postion of the actuator. |
| Three-phase circuit | A combination of circuits energized by AC that differ in phase by one-third of a cycle, that is, 120 degrees. |
| Three-phase transformer | A combination in one unit of three single-phase transformers with separate electric circuits, but having certain magnetic circuits in common. There are three magnetic circuits through the core, and the fluxes in the various circuits are displaced in phase. |
| Three-Way Switch | (single pole double throw) A switch which is used in pairs to control one load from two or more locations. |
| Threshold Current | The symmetrical RMS available current at the threshhold of the current-limiting range when tested to the industry standard. This value can be read off of a peak let-through chart where the fuse curve intersects the A-B line. A threshold ratio is the relationship of the threshold current to the fuse’s continous current rating. |
| THW | Thermoplastic vinyl insulated building wire. Flame-retardant, moisture and heat-resistant. 75°C. Dry and wet locations. |
| THWN | Same as THW but with nylon jacket overall. 75°C |
| TIA | (Telecommunications Inudstry Association) Industry trade association which works with the Electronics Industry Association (EIA) in developing standards. |
| Time Delay | A period of time when a load is energized or de-energized. At the end of the desired time period the load changes state (i.e. on or off). |
| Time Delay Fuse | A fuse which will carry an overcurrent of a specified magnitude for a minimum specified time without opening, as defined in the tri-national Fuse Standard 248. |
| Time Rating | Most motors are rated for continous duty whch means that they can operate at full load torque continuously without overheating. Motors used on certain types of applications such as waste disposal, valve actuators, hoists, and other types of intermittent loads, will frequently be rated for short term duty such as 5 minutes, 15 minutes, 30 minutes, or 1 hour. Just like a human being, a motor can be asked to handle very strenous work as long as it is not required on a continuous basis. |
| Time Switch | An electronic or electro-mechanical control, used to schedule “turn on” and “turn off” time based on the time of day. |
| Timer | An electronic or electro-mechanical control used to produce a time delay to control a load. |
| Tinning | Tinning is divided into two types: Electrotinned and Hot Dipped. Electrotinned is the process of electroplating the surface of a conductor material with a tin or tin-lead alloy. |
| Tinsel Wire | A very flexible conductor made by serving one or more very small flat conductors over a fibrous core such as a high tenacity rayon, nylon, fortisan or cotton fibers. |
| Tip | The positive conductor of a pair in a basic telephone circuit. The tip is grounded. |
| Toggle Dimming | Is achieved through up or down toggling of traditional switch style toggle used to control the dimming components. |
| Toggle Switch | A switch having a levertype actuating member which makes or breaks the switch contacts when its position is changed. |
| Topology | The physical or geometric configuration of a local area network. |
| Toroid Choke | An electronic component constructed of a ferrite ring wrapped with copper wire, used to reduce RFI generated by an electronic switching device. |
| Torque | The twisting force exerted by the shaft of a motor. Torque is measured in pound inches, pound feet, and on small motors, in terms of ounce inches. |
| Torque Test | A test designed to ascetain the stiffness of a material under given environmental conditions. |
| Totally Enclosed | Apparatus with an integral enclosure so constructed that, while not airtight, the enclosed air has no deliberate connection with external air except for draining and breathing. |
| Touch Dimming | The ability of a dimmer to control lighting levels by sensing the touch of a hand to its sensor plate. |
| TP | Parallel tinsel cord. All-rubber insulation and jacket over two extremely flexible conductors. Light duty, attached to appliances of 50W or less. For use in damp locations in lenghts of eight feet or less. |
| TPE | Thermoplastic Elastomer |
| TPO | Same construction as type PO but with extra flexible tinsel conductors. 125V |
| TPT | Same as TP but all-thermoplastic insulation and jacket. 125V |
| Tracer Stripe | When more than one color coding stripe is required, the first, or widest, stripe is the base stripe, the other, usually narrower stripes, being termed tracer stripes. |
| Transformer | A device for transferring energy in an alternating current system from one circuit to another, consisting of two independent electric circuits linked by a common magnetic circuit. |
| TRANSFORMER | A device made of two coil windings that transfers voltage from one coil to the next through electromagnetic induction. Depending upon the number of windings per coil, a transformer can be designed to step – up or step – down its output voltage from its input voltage. Transformers can only function with alternating current (AC). |
| TRANSIENT VOLTAGE PROTECTION MODULE (TVP) | A device which protects the engine controller electronics against high energy voltage transients such as alternator load dumps. |
| TRANSISTOR | A device constructed of semi – conductors that is used in circuits to control a larger current by using a smaller current for operation. Its function is the same as a relay. |
| Transparent | Targets that permit transmission of essentially all incident light. |
| Tree Wire | A cable designed to be used in conjunction with insulators, for overhead distribution, having heavy covering which reduces faults due to the touching of tree limbs in heavily wooded areas. (See spacer cable, sometimes one in the same). |
| TRIAC | (Bidirectional Triode Thyristor) A solid state output device capable of switching alternating current. |
| Triaxial | A cable construction, having three coincident axis, such as conductor, first shield and second shield all insulated from one another. |
| TRIMMER RESISTOR | A resistor used in applications where only a small resistance change is needed. |
| Triplex Cable | A cable composed of either three insulated single-conductor cables twisted together or two insulated single-conductor cables twisted together with a bare conductor or messenger. |
| True Concentric | A true concentric stranding or twisted cable is when each successive layer has a reversed direction of lay from the preceding layer. |
| TS | Two or three-conductor rubber-insulated and jacketed tinsel cord. Light duty, attached to an appliance of 50W or less. For use in damp places in lengths of eight feet or less. |
| TSO | Same as type TS but with neoprene jacket. 125V |
| TST | Polyvinyl chloride insulation and sheath, aerial and duct. |
| TT | A test designed to locate pin-holes in an insulated wire by application of an electrical potential across the material for a very short period of time while the wire is drawn through an electrode field. |
| Turnkey | An installation in which the user receives a complete operatioanl system ready to be used. |
| TVSS | Transient Voltage Surge Suppressor |
| TW | Thermoplastic vinyl-jacketed building wire, moisture-resistant. 60°C |
| Twin Cable | A cable consisting of two insulated conductors laid parallel and having a common covering. |
| Twin Coaxial | A configuration containing two separate, complete coaxial cables laid parallel or twisted around each other in one complex. |
| Twin Wire | A cable composed of two small insulated conductors laid parallel and having a common covering. |
| Twisted Pair | A cable composed of two small insulated conductors twisted together, but having no common covering. Two insulated copper wires twisted together to reduce interference from each other. |
| Twisted Pair Cable | A type of interconnection cable consisting of pairs of wire twisted together. |
| UD | Underground distribution. |
| UF | Thermoplastic underground feeder and branch circuit cable. |
| UL | Underwriters Laboratory. Standards and test that wire must meet in order to receive UL approval. |
| UL/CSA Class Fuses | General purpose fuses meeting one of the industry standards called “classes.” Fuse classifications H, J, K, L, R, CC, G and T. Qualifying fuses are typically tested and certified by UL or CSA to tri-national Fuse Standard 248. |
| Ultra-Violet Degradation | The degradation caused by long time exposure of a material to sunlight or other ultraviolet rays containing radiation. |
| Undervoltage relay | A relay that operates when the voltage applied to the relay is equal to or less than its setting. |
| Unidirectional Concentric Stranding | A unidirectional stranding where each successive layer has a different lay length thereby retaining a circular form without migration strands from one layer to another. |
| Unidirectional Stranding | A term denoting, that in a stranded conductor all layers have the same directional lay. |
| Unilay Stranding | A bunched construction having 19, 27, 37, or any number of strands which might be found in a concentric stranding. |
| Unipolor or Acyclic Machine | A direct current machine in which the voltage generated in the active conductors maintains the same direction with respect to those conductors. |
| URC | Weatherproof wire. |
| URD | Underground residential distribution. |
| USE | Underground service entrance cable, rubber-insulated, neoprene or XLP jacketed. |
| USOC (Uniform Service Order Code) | Bell system term to denote varying pin configurations on registered jacks (RJs). |
| UTP (Unshielded Twisted Pair) | Twisted-pair copper cable without metallic braid shielding – capable of high-speed voice and data transmission. The most common cabling used in the U.S. structured wiring. |
| V | Varhished-cambric insulation, with fibrous covering. |
| VACUUM FLORESCENT DISPLAY (VDC) | An anode – controlled display which emits its own light. It works like a television tube, directing streams of electrons to strike phosphorescent segments. |
| VARIABLE RESISTOR | A resistor that can beadjusted to different ranges of value. |
| Variable Speed Motor | A motor with a positively damped speed-torque characteristic which lends itself to controlled speed applications. |
| Varistor | Variable resistor |
| Varying-Speed Motor | A Motor whose speed varies with the load, ordinarily decreasing when the load increases. |
| VCB | Varnished-cambric insulation, cotton braid, flame-retarding, moisture-resisting finish. |
| VCL | Varnished-cambric insulation, lead-covered cable. Ends must be hermetically sealed. |
| VD | Indicates a twin wire having two type V conductors laid parallel under an outer fibrous covering. |
| Velocity of Propagation | In cable measurements, a function of dielectric constant. The transmission speed of an electrical signal down a length of cable compared to speed in free space – expressed as a percentage of speed in free space. |
| Ventilated | Provided with a means to permit circulation of air sufficient to remove an excess of heat, fumes or vapors. |
| Vertical-break switch | A switch in which the travel of the blade is in a plane perpendicular to the plane of the mounting base. |
| VG | Varnished-glass tape over a flexible copper conductor. Varnished-glass or nylon braid. 600V or 3000V, 130°C |
| VIP | Vulcanized interlinked polyethylene. |
| VISCOSITY | The internal resistance of a fluid, caused by molecular attraction, which makes it resist a tendency to flow. |
| VM | Indicates a cable having two or more type V conductors twisted together under an outer fibrous covering. |
| Volt | A unit of electromotive force. |
| VOLT | A unit of electrical pressure (or electromotive force) which causes current to flow in a circuit. One volt is the amount of pressure required to cause one ampere of current to flow against one ohm of resistance. |
| Volt Amperes or Apparent Power | The product of the voltage across circuit and the current in the circuit. |
| Voltage | A difference of potential measured in volts. The electric pressure available to cause a flow of electrons. |
| VOLTAGE | That force which is generated to cause current to flow in an electrical circuit. It is also referred to as electromotive force or electrical potential. Voltage is measured in volts. |
| Voltage Drop | A term expressing the amount of voltage loss from original input in a conductor of given size and length. |
| Voltage Rating | The maximum open circuit voltage in which a fuse can be used, yet safely interrupt an over current. Exceeding the voltage rating of a fuse impairs its ability to clear and overload or short circuit safely. |
| Voltage Ratio | The voltage ratio of a transformer is the ratio of the r.m.s. primary terminal voltage to the r.m.s. secondary current, under specified conditions of load. |
| VOLTAGE REGULATOR | A device that controls the strength of a magnetic field produced by a generator or alternator. It prevents the battery from being overor undercharged during high – or low – speed operation of the generator or alternator. |
| Voltage relay | One which functions at a predetermined value of voltage. A voltage relay may be either an over-voltage relay or an under-voltage relay. |
| Voltage Standing Wave Ratio | 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 | The stress found within a material when subjected to an electrical charge. |
| Voltmeter | An instrument of high resistance for measuring differences of pressures in volts. |
| VOLTMETER | An instrument for measuring the force in volts of an electrical current. This is the difference of potential (voltage) between different points in an electrical circuit. Voltmeters are connected across (parallel to) the points where voltage is to be measured. |
| Volume Resistivity | The volume resistance between two electrodes of unit area and unit distance apart that are in contact with, or imbedded in, a specimen, is the ratio of the direct voltage applied to the electrodes to that portion of the current between them that is distributed through the volume of the specimen. Usually expressed in ohms/centimeter. |
| VW-1 | Vertical wire flame test, formerly designated as FR1. |
| W | Heavy duty portable power cable, one to six conductors. 600V, without grounds. |
| W/G | With ground |
| W/O/G | Without ground |
| Wall Plate | A plate designed to enclose a device box with or without a divice installed in the box. |
| Wall socket | Any socket placed in a wall for the purpose of admitting a plug for making electrical connection with supply wires. |
| Wall Thickness | A term expressing the thickness of a layer of applied insulation or jacket. |
| Water Absorption Test | A method to determine the water absorbed through an insulating material after a given water immersion period. |
| Waterblocked Cable | A cable specially constructed with no internal voids in order to allow no longitudinal water passage under a given pressure. |
| Watt | A unit of electrical power; the power of one ampere of current pushed by one volt of electromotive force. |
| WATT | A unit of measure for indicating the electrical power applied in a circuit. It is obtained by multiplying the current (in amperes) by the electrical pressure (in volts) which cause it to flow. That is: watts = amperes x volts. |
| WATT-HOUR | A unit of electrical energy. It indicates the amount of work done in an hour by a circuit at a steady rate of one watt. That is, watthours = ampere – hours x volts. |
| WAVE | A signal that is produced by varying a continuous flow of current within a circuit. Waveforms can be created by either AC or DC current. |
| Wave Length | The distance, measured in the direction of propogation, of a repetitive electrical pulse or waveform between two successive points that are characterized by the same phase vibration. |
| WAVEFORM | A graphical representation ofelectrical cycles which shows the amount of variation in amplitude over some period of time. |
| Wave-Form or Wave-Shape | The shape of the curve obtained when the instantaneous values of an alternating current are plotted against time in rectangular coordinates. The distance along the time axis corresponding to one complete cycle of values is usually taken as 2(pi) radian, or 360 electrical degrees. |
| Weatherproof | A device constructed or protected such that exposure to weather will not interfere with successful operation. (N.E.C.) |
| Welder Protector | A fuse with special characteristics to meet heavy inrush current demands of an electric welder and protect the welder on short circuits. |
| Wet Location; Cover Open | A cover, UL listed in accordance with specific test standards for use in wet and damp locations with the cover opened (plug cap inserted) or closed. |
| Wet Location; Only with Cover Closed | A cover UL listed in accordance with specific test standards for use in damp locations with the cover closed, or wet locations only when cover is closed. |
| Wetting | The ability of a material to absorb moisture. |
| Wicking | The longitudinal flow of a liquid in a wire or cable construction due to capillary action. |
| WINDING | The coiling of a wire about itself or about some object. Often identified as a series winding, a shunt winding, etc. |
| Wire | (1) A single piece of slender, flexible metal ranging in approximate size from a piece that is difficult to bend by hand to a fine thread. (2) Several wires as in (1) twisted together. (3) Wires as in (1) or (2) insulated. |
| Wire Mesh Grip | (Flexcor) Woven wire mesh holding devices used to support, pull, or relieve strain exerted upon cables, conduit, tubing and various other items. |
| Wiring Closet | Termination point for Customer premises wiring offering access to service personnel. |
| WIRING HARNESS | Thf3 trunk and branches which feed an electrical circuit. Wires from one part of the circuit enter the trunk, joining other wires, and then emerge at another point in the circuit. |
| Withstand Rating | The maximum current that an unprotected electrical component can sustain for a specified period of time without the occurence of extensive damage. |
| Work Area Outlet | A connecting device in the work area where horizontal cable terminates and work area equipment can be connected. Also called information outlet and telecommunications outlet. |
| Workstation | The location where telecommunications cabling is connected to work area equipment (PCs and peripherals) by means of a telecommunications outlet. Also called work area outlet and information outlet. |
| WP | Weatherproof construction, two or three impregnated cotton braids. 80°C |
| W-Type | Same as Y type except having three cord connectors arranged in the form of the letter W. |
| X | Two FX wires twisted together, color coded. 125V, 60°C. |
| XHHW | High temperature (90°C) chemically cross-linked polyethylene jacketed small diamter building wire. |
| XLP | Cross-linked polyethylene. |
| XT | Two FXT wires twisted together, color coded. 125V, 60°C |
| Yield Strength | The minimum stress at which a material will start to physically deform without further increase in load. |
| Y-Type | An adapter in the form of a letter Y having two cord connectors on one end and a male plug on the other end. |
| Z | Symbol for impedance |
| ZENER DIODE (Reverse Bias Direction Diode) | A semiconductor device that will conduct current in the reverse direction when the voltage becomes higher than a predetermined voltage. |
| Zero (Balance) | The output of the transducer when zero pressure is applied. |