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What is AWG

Jan 22, 2019

What is AWG

American wire gauge (AWG), also known as the Brown & Sharpe wire gauge, is a logarithmic stepped standardized wire gauge system used since 1857, predominantly in North America, for the diameters of round, solid, nonferrous, electrically conducting wire. Dimensions of the wires are given in ASTM standard B 258.[1] The cross-sectional area of each gauge is an important factor for determining its current-carrying ampacity.

Increasing gauge numbers denote decreasing wire diameters, which is similar to many other non-metric gauging systems such as British Standard Wire Gauge (SWG), but unlike IEC 60228, the metric wire-size standard used in most parts of the world. This gauge system originated in the number of drawing operations used to produce a given gauge of wire. Very fine wire (for example, 30 gauge) required more passes through the drawing dies than 0 gauge wire did. Manufacturers of wire formerly had proprietary wire gauge systems; the development of standardized wire gauges rationalized selection of wire for a particular purpose.

The AWG tables are for a single, solid, round conductor. The AWG of a stranded wire is determined by the cross-sectional area of the equivalent solid conductor. Because there are also small gaps between the strands, a stranded wire will always have a slightly larger overall diameter than a solid wire with the same AWG.

The table below shows various data including both the resistance of the various wire gauges and the allowable current (ampacity) based on a copper conductor with plastic insulation. The diameter information in the table applies to solid wires. Stranded wires are calculated by calculating the equivalent cross sectional copper area. Fusing current (melting wire) is estimated based on 25 °C (77 °F) ambient temperature. The table below assumes DC, or AC frequencies equal to or less than 60 Hz, and does not take skin effect into account. "Turns of wire per unit length" is the reciprocal of the conductor diameter; it is therefore an upper limit for wire wound in the form of a helix (see solenoid), based on uninsulated wire.

AWGDiameterTurns of wire, without insulationAreaCopper wire
Resistance/length[7]Ampacity,[8] at 20 °C insulation material temperature rating,
or for single unbundled wires in equipment for 16 AWG and smaller[9]
Fusing current[10][11]
60 °C75 °C90 °CPreece[12][13][14][15]Onderdonk[16][15]
(in)(mm)(per in)(per cm)(kcmil)(mm2)(mΩ/m[a])(mΩ/ft[b])(A)~10 s1 s32 ms
0000 (4/0)0.4600[c]11.684[c]2.170.8562121070.16080.049011952302603.2 kA33 kA182 kA
000 (3/0)0.409610.4052.440.96116885.00.20280.061801652002252.7 kA26 kA144 kA
00 (2/0)0.36489.2662.741.0813367.40.25570.077931451751952.3 kA21 kA115 kA
0 (1/0)0.32498.2513.081.2110653.50.32240.098271251501701.9 kA16 kA91 kA
10.28937.3483.461.3683.742.40.40660.12391101301451.6 kA13 kA72 kA
20.25766.5443.881.5366.433.60.51270.1563951151301.3 kA10.2 kA57 kA
30.22945.8274.361.7252.626.70.64650.1970851001151.1 kA8.1 kA45 kA
40.20435.1894.891.9341.721.20.81520.2485708595946 A6.4 kA36 kA
795 A5.1 kA28 kA
60.16204.1156.172.4326.313.31.2960.3951556575668 A4.0 kA23 kA
561 A3.2 kA18 kA
80.12853.2647.783.0616.58.372.0610.6282405055472 A2.5 kA14 kA
396 A2.0 kA11 kA
100.10192.5889.813.8610.45.263.2770.9989303540333 A1.6 kA8.9 kA
280 A1.3 kA7.1 kA
120.08082.05312.44.876.533.315.2111.588202530235 A1.0 kA5.6 kA
198 A798 A4.5 kA
140.06411.62815. A633 A3.5 kA
140 A502 A2.8 kA

18117 A398 A2.2 kA
99 A316 A1.8 kA
180.04031.02424.89.771.620.82320.956.38510141683 A250 A1.4 kA
190.03590.91227.911.01.290.65326.428.05170 A198 A1.1 kA
200.03200.81231.312.31.020.51833.3110.1551158.5 A158 A882 A
210.02850.72335.113.80.8100.41042.0012.8049 A125 A700 A
220.02530.64439.515.50.6420.32652.9616.145741 A99 A551 A
230.02260.57344.317.40.5090.25866.7920.3635 A79 A440 A
240.02010.51149.719.60.4040.20584.2225.672.13.529 A62 A348 A
250.01790.45555.922.00.3200.162106.232.3724 A49 A276 A
260.01590.40562.724.70.2540.129133.940.811.32.220 A39 A218 A
270.01420.36170.427.70.2020.102168.951.4717 A31 A174 A
280.01260.32179.131.10.1600.0810212.964.900.831.414 A24 A137 A
290.01130.28688.835.00.1270.0642268.581.8412 A20 A110 A
300.01000.25599.739.30.1010.0509338.6103.20.520.8610 A15 A86 A
310.008930.22711244.10.07970.0404426.9130.19 A12 A69 A
320.007950.20212649.50.06320.0320538.3164.10.320.537 A10 A54 A
330.007080.18014155.60.05010.0254678.8206.96 A7.7 A43 A
340.006300.16015962.40.03980.0201856.0260.90.180.35 A6.1 A34 A
350.005610.14317870.10.03150.01601079329.04 A4.8 A27 A
360.00500[c]0.127[c]20078.70.02500.01271361414.84 A3.9 A22 A
370.004450.11322588.40.01980.01001716523.13 A3.1 A17 A
380.003970.10125299.30.01570.007972164659.63 A2.4 A14 A
390.003530.08972831110.01250.006322729831.82 A1.9 A11 A
400.003140.07993181250.009890.00501344110491 A1.5 A8.5 A

AWG gauges are also used to describe stranded wire. The AWG gauge of a stranded wire represents the sum of the cross-sectional areas of the individual strands; the gaps between strands are not counted. When made with circular strands, these gaps occupy about 25% of the wire area, thus requiring the overall bundle diameter to be about 13% larger than a solid wire of equal gauge.

Stranded wires are specified with three numbers, the overall AWG size, the number of strands, and the AWG size of a strand. The number of strands and the AWG of a strand are separated by a slash. For example, a 22 AWG 7/30 stranded wire is a 22 AWG wire made from seven strands of 30 AWG wire.

content source: https://en.wikipedia.org/wiki/American_wire_gauge