The table below lists the Aluminum wire Characteristics for different
gauges of the American Wire Gauge [AWG].
The American Wire Gauge provides a means of specifying wire diameters.
For each different AWG [wire size] the table provides;
the Diameter [in mils], Diameter [in
Circular mils], the resistance per 1000 foot, the Fusing current, and
Pounds per Foot [number of feet required to weigh 1 pound].
Read the notes below the table to determine how the Ampacity was derived. The
larger the AWG number, the smaller diameter wire.
The table is based on an ambient temperature of 25oC. Conductor size is based one or
more of the following considerations:
Current carrying capacity [inducing a rise in wire temperature, in
high-voltage lines], Short circuit current, or Voltage drop [long low voltage lines].
AWG | Diam. (mils) | Circular mils | Ohms/1000ft | Fusing Current | Pounds/1000ft |
0000 | 460 | 212000 | 0.0804 | - | 195.0 |
000 | 410 | 168000 | 0.101 | - | 154.0 |
00 | 365 | 133000 | 0.128 | - | 122.0 |
0 | 324.85 | 105000 | 0.161 | - | 97.0 |
1 | 289 | 83700 | 0.203 | - | 76.9 |
2 | 258 | 66400 | 0.256 | - | 61.0 |
3 | 229 | 52600 | 0.323 | - | 48.4 |
4 | 204 | 41700 | 0.408 | - | 38.4 |
5 | 182 | 33100 | 0.514 | - | 30.4 |
6 | 162 | 26300 | 0.648 | 495.0 | 24.1 |
7 | 144 | 20800 | 0.817 | 416.0 | 19.1 |
8 | 128 | 16500 | 1.03 | 349.0 | 15.2 |
9 | 114 | 13100 | 1.30 | 299.0 | 12.0 |
10 | 102 | 10400 | 1.64 | 247.0 | 9.55 |
11 | 90 | 8230 | 2.07 | 207.0 | 7.57 |
12 | 81 | 6530 | 2.61 | 174.0 | 6.0 |
13 | 72.0 | 5180 | 3.29 | 146.0 | 4.76 |
14 | 64 | 4110 | 4.14 | 123.0 | 3.78 |
15 | 57 | 3260 | 5.22 | 103.0 | 2.99 |
16 | 51 | 2580 | 6.59 | 88.80 | 2.37 |
17 | 45 | 2050 | 8.31 | 72.90 | 1.88 |
18 | 40 | 1620 | 10.5 | 61.40 | 1.49 |
19 | 36 | 1290 | 13.2 | 51.60 | 1.18 |
20 | 32.0 | 1020 | 16.7 | 43.20 | 0.939 |
21 | 28.5 | 810 | 21.0 | - | 0.745 |
22 | 25.3 | 642 | 26.5 | 30.50 | 0.591 |
23 | 22.6 | 509 | 33.4 | - | 0.468 |
24 | 20.1 | 404 | 42.1 | 21.60 | 0.371 |
25 | 17.9 | 320 | 53.1 | - | 0.295 |
26 | 15.9 | 254 | 67.0 | 15.20 | 0.234 |
27 | 14.2 | 202 | 84.4 | - | 0.185 |
28 | 12.6 | 160 | 106 | 10.70 | 0.147 |
29 | 11.3 | 127 | 134 | - | 0.117 |
30 | 10.0 | 101 | 169 | 7.580 | 0.0924 |
31 | 8.9 | 79.7 | 213 | - | 0.0733 |
32 | 8.0 | 63.2 | 269 | 5.320 | 0.0581 |
33 | 7.1 | 50.1 | 339 | - | 0.0461 |
34 | 6.3 | 39.8 | 428 | 3.790 | 0.0365 |
35 | 5.6 | 31.5 | 540 | - | 0.0290 |
36 | 5.0 | 25.0 | 681 | 2.68 | 0.0230 |
37 | 4.5 | 19.8 | 858 | - | 0.0182 |
38 | 4.0 | 15.7 | 1080 | 1.85 | 0.0145 |
39 | 3.5 | 12.5 | 1360 | - | 0.0115 |
40 | 3.1 | 9.9 | 1720 | 1.31 | 0.0091 |
Notes:
For the same conductivity aluminum wire is about two gauges larger than copper wire.
The table above only lists the AWG standard. The wire size is different
between the American Wire Gage [AWG] and the British standard.
AWG [American Wire Gauge] may also be called the Brown and Sharpe
(B&S) Wire Gauge.
The Birmingham Wire Gauge [BWG] is used for steel armor wire.
Watch for round-off errors, as many numbers were rounded. Use the table
as a guide.
The weight does not include wire insulation. The weight of the wire is
critical in some applications.
Circular mils is the diameter squared in mils.
The wire fusing [melting] current is based on the material the wire is
made of, the diameter of the wire and the melting point of the the
material.
The wire fusing current of a wire is provided in tables as
constant current or as [a larger] current for some given amount of
time.
I found this formula used on a few different sites [un-verified];
I=Ad(3/2) @ d is in inches, A is a constant: A = 10,244 for
Copper. A = 7,585 for Aluminum.
I have listed a number of values for fusing current in the table above,
for selected AWG sizes.
Copper wire properties are listed under on the Copper Electrical Wire page. Manufacturers listing for Electrical Wire and
Cable.
Related topic; Aluminum to Copper Wire Splice, an AC wire example [house wiring].
Refer to the How to Derate
Components page for derating wire with other then Teflon
insulation
Refer to the National Electrical Code [NEC] to determine cable sizing for
premises wiring.
Also see the Wire Insulation Color Code page; Color
coding of wire insulation based on application.
This page represents my notes on the subject, purchase
one of the standards or specifications referenced on this page when doing
professional work.
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