W - (1) Symbol for watt or wattage. (2) A UL cable type. Heavy-duty portable power cable, one to six conductors. 600 V, without grounds.
Wall thickness - The thickness of a applied insulation or jacket. Generally wall thickness increases for higher voltages.
WAN (wide area network) - A network that uses common carrier-provided lines; contrast with LAN.
Water absorption - A test to determine the amount of water absorbed by a material after a given immersion period.
Water-blocked cable - A multiconductor cable having interstices filled with a water-blocking compound to prevent water flow or wicking.
Water-cooled leads - Furnace cables. High-energy cables. Usually welding cable strands cabled with a hose core for carrying coolant used in heavy-duty welding equipment, electric furnace applications, plating and various chemical processes.
Water treeing - A type of insulation deterioration that can occur after long-term immersion in water with an electrical stress applied.
Waterfall - The point at which cables installed horizontally in a tray transition to a vertical section of tray.
WATS (wide area telephone service watt) - A unit of electrical power. One watt is equivalent to the power represented by one ampere of current under a pressure of one volt in a DC circuit.
WATT - A unit of electrical power (energy consumed per unit time). One watt is equivalent to the power represented by one ampere of current under a pressure of one volt in a DC circuit.
Wave front - (1) That portion of an impulse (in time or distance) between the 10 percent point and the point at which the impulse reaches 90 percent of crest value. (2) The rising part of an impulse wave.
Waveform - A graphical representation of a varying quantity. Usually, time is represented on the horizontal axis and the current or voltage value is represented on the vertical axis.
Wavelength - The distance between the nodes of a wave. The ratio of the velocity of the wave to the frequency of the wave.
Waveshape representation - The designation of current or voltage by a combination of two numbers. For other than rectangular impulses: (a) virtual duration of the wave front in microseconds; and (b) time in microseconds from virtual zero to the instant at which one-half of the crest value is reached on the tail. For rectangular impulses: (a) minimum value of current or voltage; and (b) duration in microseconds.
WEEE - Waste Electrical and Electronic Equipment. A European Union regulation (Directive 2002/96/EC) which holds the manufacturer responsible for proper recycling or disposal when it reaches end-of-life. See also RoHS and REACH.
Weight resistivity - The resistance in ohms at a specified temperature of a copper wire of uniform cross section and of unit weight and unit length.
Welding - Joining the ends of two wires, rods or groups of wires: (a) by fusing, using the application of heat or pressure or both, by means of a flame torch, electric arc, or electric current; or (b) by cold pressure.
WEP (wired equivalent privacy) - A 128 bit wireless encryption scheme.
Wheatstone bridge - A device used to measure DC resistance. See BRIDGE.
Wi-Fi (wireless fidelity) - Meant to be used generically when referring of any type of 802.11 network whether 802.11b, 802.11a, dual-band, etc. The term is promulgated by the Wi-Fi Alliance. Wi-Fi Alliance is a nonprofit international association formed in 1999 to certify interoperability of wireless Local Area Network products based on IEEE 802.11 specification.
Wicking - The longitudinal flow of a liquid in a wire or cable due to capillary action.
Wideband - A communications channel offering a transmission bandwidth greater than a voice-grade channel. Synonymous with broadband.
Wire - A rod or filament of drawn or rolled metal whose length is great in comparison with the major axis of its cross section.
Wire cross-connect - The apparatus at which twisted pairs are terminated, to permit circuit rearrangement and testing. Cross-connects, usually located in equipment rooms and service closets, terminate house cables and station cables. Wire cross-connects in an ISN system employ either the traditional 66-type wiring or the newer 110-type wiring. The 66-type cross-connects use many single jumper wires for circuit administration and require a trained person with special tools to make connections. The 110-type cross-connect uses patch cords with molded, snap-on connectors allowing one-step administration of multiple wires and easy movement of connections; thus it permits customer participation, making it the preferred method in an ISN system.
Wire braid - Flexible wire constructed of small size strands in tubular form. Used for shielding or connections where constant flexing is required.
Wire Gauge (AWG) - The American Wire Gauge, originally called Brown & Sharpe Gauge. A system of numerical wire sizes starting with the lowest numbers for the largest sizes. Gauge sizes are each 20.6 percent apart based on the cross-sectional area.
Wire nut - A closed-end splice that is screwed on instead of crimped.
Wire-wrapped connection - A solderless connection made by wrapping bare wire around a square or rectangular terminal with a power or hand tool.
Wire wrapping tools - Portable electric tools and automatic stationary machines used to make solderless wrapped connections of wires to terminals.
Wiring block - A molded plastic block that is designed in various configurations to terminate cable pairs and establish pair location on a 110-type cross-connect.
Wiring closet - A room that contains one or more distribution racks and panels that are used to connect various cables together (via patch cables) to form physical networks. Termination point for customer premises wiring, offering access to service personnel; generally serves a specific area, with multiple wiring closets that are cross-connected.
Wiring concentrator - A lobe concentrator that allows multiple attaching devices access to the ring at a central point such as a wiring closet or in an open work area.
Withstand test voltage - The voltage that the device must withstand without flashover, disruptive discharge, puncture or other electric failure when voltage is applied under specified conditions.
Workstation - (1) Input/output equipment at which an operator works; (2) A station at which a user can send data to, or receive data from, a computer or other workstation for the purpose of performing a job.
WORM - Write once read many.
WP - Weatherproof construction for overhead wires.
WPA (Wi-Fi Protected Access) - A wireless security level higher than WEP.
Wrapper - An insulating barrier applied as a sheet of tape wrapped around a coil periphery.