Wire gauge - AbsoluteAstronomy.com

Wire gauge is a measurement

Measurement

Measurement is the process or the result of determining the ratio of a physical quantity, such as a length, time, temperature etc., to a unit of measurement, such as the metre, second or degree Celsius...

of how large a wire

Wire

A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity and telecommunications signals. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standard sizes are determined by various...

is, either in diameter

Diameter

In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...

or cross sectional

Cross section (geometry)

In geometry, a cross-section is the intersection of a figure in 2-dimensional space with a line, or of a body in 3-dimensional space with a plane, etc...

area

Area

Area is a quantity that expresses the extent of a two-dimensional surface or shape in the plane. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat...

. This determines the amount of electric current

Electric current

Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...

a wire can safely

Safety

Safety is the state of being "safe" , the condition of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or other types or consequences of failure, damage, error, accidents, harm or any other event which could be...

carry, as well as its electrical resistance

Electrical resistance

The electrical resistance of an electrical element is the opposition to the passage of an electric current through that element; the inverse quantity is electrical conductance, the ease at which an electric current passes. Electrical resistance shares some conceptual parallels with the mechanical...

and weight

Weight

In science and engineering, the weight of an object is the force on the object due to gravity. Its magnitude , often denoted by an italic letter W, is the product of the mass m of the object and the magnitude of the local gravitational acceleration g; thus:...

per unit

Units of measurement

A unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention and/or by law, that is used as a standard for measurement of the same physical quantity. Any other value of the physical quantity can be expressed as a simple multiple of the unit of...

of length

Length

In geometric measurements, length most commonly refers to the longest dimension of an object.In certain contexts, the term "length" is reserved for a certain dimension of an object along which the length is measured. For example it is possible to cut a length of a wire which is shorter than wire...

. Wire gauge is applicable to both electrical and non-electrical wires, being important to electrical wiring

Electrical wiring

Electrical wiring in general refers to insulated conductors used to carry electricity, and associated devices. This article describes general aspects of electrical wiring as used to provide power in buildings and structures, commonly referred to as building wiring. This article is intended to...

and to structural cable.

Types

Gauges may be broadly divided into two groups, the empirical

Empirical

The word empirical denotes information gained by means of observation or experimentation. Empirical data are data produced by an experiment or observation....

and the geometric. The first includes all the older gauge measurements, notably the Birmingham

Stubs Iron Wire Gauge

The Stubs Iron Wire Gauge system is used to specify thickness or diameter of metal wire, strip, and tube products...

(B.W.G.) and the Lancashire

Lancashire

Lancashire is a non-metropolitan county of historic origin in the North West of England. It takes its name from the city of Lancaster, and is sometimes known as the County of Lancaster. Although Lancaster is still considered to be the county town, Lancashire County Council is based in Preston...

or Stubs. The origin of the B.W.G. is lost in obscurity. The numbers of wire were in common use earlier than 1735. It is believed that they originally were based on the series of drawn wires, No. 1 being the original rod, and succeeding numbers corresponding with each draw, so that No. 10, for example, would have passed ten times through the draw plate. But the Birmingham and the Lancashire gauge, the latter being based on an averaging of the dimensions collated from a large number of the former in the possession of Peter Stubs of Warrington, have long held the leading position, and are still retained and used probably to a greater extent than the more recent geometrical gauges.

The first attempt to adopt a geometrical system was made by Messrs Brown & Sharpe

Brown & Sharpe

Brown & Sharpe is a division of Hexagon Metrology, Inc., a multinational corporation focused mainly on metrological tools and technology. During the 19th and 20th centuries, Brown & Sharpe was one of the most well-known and influential firms in the machine tool industry...

in 1855. They established a regular progression of thirty-nine steps between the English sizes, No. 0000 (460 mils or about 12 mm) and No. 36 (5 mils or about 0.13 mm). Each diameter was multiplied by 0.890526 to give the next lower size. This is now the American wire gauge

American wire gauge

American wire gauge , also known as the Brown & Sharpe wire gauge, is a standardized wire gauge system used since 1857 predominantly in the United States and Canada for the diameters of round, solid, nonferrous, electrically conducting wire...

(AWG), and is used to a considerable extent in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

.

The Imperial Standard Wire Gauge

Standard wire gauge

British Standard Wire Gauge is a set of wire sizes given by BS 3737:1964 , and is generally abbreviated to SWG. It is also known as: Imperial Wire Gauge or British Standard Gauge. Use of SWG sizes has fallen greatly in popularity, but is still used as a measure of thickness in guitar strings and...

, which has been sanctioned by the British Board of Trade, is one that was formulated by J. Latimer Clark. Incidentally, one of its recommendations is that it differs from pre-existing gauges scarcely more than they differ among themselves, and it is based on a rational system, the basis being the mil

Circular mil

A circular mil is a unit of area, equal to the area of a circle with a diameter of one mil . It is a convenient unit for referring to the area of a wire with a circular cross section, because the area in circular mils can be calculated without reference to pi .The area in circular mils, A, of a...

. No. 7/0, the largest size, is 0.50 in. (500 mils or 12.7 mm) in diameter, and the smallest, No. 50, is 0.001 in. (1 mil or about 25 µm) in diameter. Between these the diameter, or thickness, diminishes by 10.557%, and the weight diminishes by 20%.

The current British Standard for metallic materials, which includes wire, is BS 6722:1986, which is a solely metric standard. This replaces the now-withdrawn BS 3737:1964, which used the SWG system.

Measuring

In commerce, the sizes of wire are estimated by a device, also called gauge

Gauge (engineering)

In engineering, a gauge or gage, is used to make measurements. A wide variety of tools exist which serve such funtions, ranging from simple pieces of material against which sizes can be measured to complex pieces of machinery...

s, which consist of plates of circular or oblong form having notches of different widths round their edges to receive wire and sheet metals of different thicknesses. Each notch is stamped with a number, and the wire or sheet, which just fits a given notch, is stated to be of, say, No. 10, 11, 12, etc., of the wire gauge.

The circular forms of wire gauge measurement devices are the most popular, and are generally 3¾ in. (95 mm) in diameter, with thirty-six notches; many have the decimal equivalents of the sizes stamped on the back. Oblong plates are similarly notched. Rolling mill gauges are also oblong in form. Many gauges are made with a wedge-like slot into which the wire is thrust; one edge being graduated, the point at which the movement of the wire is arrested gives its size. The graduations are those of standard wire, or in thousandths of an inch. In some cases both edges are graduated differently to serve for comparison between two systems of measurement. A few gauges are made with holes into which the wire has to be thrust. All gauges are hardened and ground to dimensions.

In some applications wire sizes are specified as the cross sectional area of the wire, usually in mm². Advantages of this system include the ability to readily calculate the physical dimensions or weight of wire, ability to take account of non-circular wire, and ease of calculation

Calculation

A calculation is a deliberate process for transforming one or more inputs into one or more results, with variable change.The term is used in a variety of senses, from the very definite arithmetical calculation of using an algorithm to the vague heuristics of calculating a strategy in a competition...

of electrical properties.

External links

Wire Gauge to Diameter—Diameter to Wire Gauge Converter - Online calculator converts gauge to diameter or diameter to gauge for any wire size.
Calculation: round electric cable diameter to circle cross-sectional area and vice versa
Wire gauge conversion chart
Standard wire sizes, Kaye & Laby, NPL

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.

Types

Measuring

See also

External links