W
(1) Symbol for watt or wattage
(2) UL cable type. Heavy duty portable power cable, one to six conductors. 600V, without grounds

Wall Thickness
The thickness of the applied insulation or jacket

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

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 Trees
A type of insulation deterioration that can occur after long term immersion in water with an electrical stress applied

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

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

Wave Front
(1) That portion of an impulse (in time or distance) between the 10% point and the point at which the impulse reaches 90% of crest value
(2) The rising part of an impulse wave

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,
(b) time in microseconds from virtual zero to the instant at which one-half of the crest is reached on the tail
For rectangular impulses:
(a) minimum value of current or voltage, (b) duration in microseconds

Weight Resistivity
The resistance in ohms at a specified temperature of a body 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

Wheatstone Bridge
A device used to measure DC to capillary action

Wicking
The logitudinal flow of a liquid in a wire or cable due to capillary action

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 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% 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

Withstand Test Voltage
The voltage that the device must withstand without flashover, disruptive charge, puncture, or other electric failure when voltage is applied under specified conditions

WP
Weatherproof construction for overhead wires

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

Wrapper
An insulating barrier applied as a sheet of tape wrapped around a coil periphery

Wiring Systems
Cable systems and accessories should be installed in positions that prevent them from being subject to mechanical damage, corrosion, chemical attack and other detrimental environmental conditions. Selection of the wiring system and cable type must consider these influences - and where exposure to such conditions are unavoidable, protective issues such as minimizing the risk of mechanical damage by the use of appropriate armored cable types should be considered