American Wire Gauge
American Wire Gauge, abbreviated AWG, in English speaking countries also known as Brown & Sharpe wire gauge known, is an encoding for wire diameter and is mainly used in North America. It features electric wires of strands and solid wires and is mainly used in electrical engineering to describe the cross-section of wires. The system was introduced in 1857 by Joseph Rogers Brown at the company Brown & Sharpe.
Derivation
The American wire gauge system is based on the production process of wires and pressing the number of the drawing steps of the wire. Because (copper ) wire solidified during drawing is at a threshold risk of tearing. Therefore, the degree of contraction is limited. After heat treating the wire can be pulled further. Through each train is - at constant volume - the wire thinner and longer.
It deals specifically with the diameters of two stages:
The standard ASTM B 258-02 defines the ratio of successive AWG sizes as:
From this it can be deduced the formula for calculating the diameter of the AWG number:
Or
In the standard is set so that the diameter should be no more than four significant digits, based on the inch unit in the tables. The resolution should include 0.1 mil for 44 AWG and 45 AWG 0.01 mil for ascending.
The calculation of the AWG number of the diameter is made by:
While negative values of AWG are possible, which are written as 00 AWG, 000 AWG and 0000 AWG (0.46 ").
Multiple and fine stranded cables ( cords ) have because of the adjacent individual wires to a 14% to 13% larger overall diameter.
Table for AWG wires ( single core )
The fully coated with the above conversion formula in units of length shown in the following table. ( 1 inch = 25.4 mm, 1 kcmil = 0.5067 mm ²)
The specific resistance of copper is assumed to be 0.0178 Ω mm ² / m.
Preferred sizes are highlighted. The cross-sections specified as equivalent are recommended by the European manufacturers replacement models in the usual metric graduations.
Equivalent ( mm ²)
( Stubs )
Composition of stranded conductors
In the composition of stranded conductors such as wires in the electrical properties of the same AWG Nominal sizes may differ materially voneninander and do not meet the above specifications for solid conductors ( solid wires ). For example, the electrically effective cross sections for stranded wire with identical AWG number are not equal to those of a full wire.
In the following tables, the construction of more common and fine-stranded conductors of AWG system is shown. Other not mentioned here compositions are possible.
Derived applications
The name of the AWG size (eg 32 AWG ) is required in the wire-wrap technique for determining the winding insert.
Criticism
The AWG system is based on an existing at the time of development of manufacturing processes. For the user, it is important to know how often a wire is drawn; only the dimensions are interesting. AWG negates technological developments as well as future, material scientific data. The wire codes for wire drawing practice from the 1800s, was introduced by the needs of the users and is still in use in many countries.
Specifically, the United States ignore the fact that they are already in 1878 joined the Metre Convention and hold on the AWG system fixed. As a concession will only inch converted to metric units. This means that, for example, European manufacturers are forced by electric cables, connectors and crimp terminals to establish and adapt their product range according to special designs for the U.S. market.
For AWG stranded conductors, the total size is not sufficient. Depending on the design and manufacturer, significant variations in the electrical properties may result, for realistic calculations, the data sheet of the manufacturer is therefore required.
Other wire encodings
In addition to the American Wire Gauge exist in the UK Imperial Standard Wire Gauge ( ISWG ), also known simply Standard Wire Gauge ( SWG) called, and Birmingham Wire Gauge ( BWG), also stubs Wire Gauge named that are equally characterized by a number code. Another wire is the encoding of Washburn & Moen ( W & M).
Also for the starting material of drills is in Anglo-American countries still own coding, drill wire gauge, in application. The range covers the range from # 107 to # 0.0483 mm as the smallest Z with 10.4902 mm, the largest bore diameter.
Names for cables that reference the real cross-section are standardized according to IEC 60228.