# DC resistance of conductor at 20°C

From standard IEC 60228 Ed.3.0 and UL 1581 (up to 2000 kcmil) and ASTM B8-11/B231-04 and ICEA S-94-649-2000 (2500 kcmil and above).

Please note that we have added the values for 3000, 3200, and 3500 mm² as published in the IEC 60228 edition 4 committee draft, published 2021-11-12. In this draft, the value for aluminium with 2500 mm² was changed from 0.0127 to 0.0119. The new value is in fact more reasonable and so we decided to use this value even though the edition 4 is only draft. If you want to use the value from the currently still valid edition 3, you can set it manually in the cable editor.

The tabulated standard DC resistance values for cable conductors at 20°C are in $\Omega$/km. For calculation, values in in $\Omega$/m are used.

Symbol
$R_{co}$
Unit
$\Omega$/km
Formulae
${10}^9\frac{\rho_c}{A_c}$
Used in
$R_0$
Choices
Size
Area
mm²
solid
copper
plain
solid
copper
coated
solid
alu
stranded
copper
plain
stranded
copper
coated
stranded
alu
flexible
class 5/C
copper
plain
flexible
class 5/C
copper
coated
flexible
class 6/D
copper
plain
flexible
class 6/D
copper
coated
26 AWG0.128138143225140150230
24 AWG0.20585.989.314187.694.2144
22 AWG0.32454.356.488.955.459.490.9
0.5 mm$^2$0.536.036.757.4736.036.757.4739.040.139.040.1
20 AWG0.51933.935.255.434.636.757.1
0.75 mm$^2$0.7524.524.838.3124.524.838.3126.026.726.026.7
18 AWG0.82321.422.235.121.823.235.8
1.0 mm$^2$1.018.118.228.7418.118.228.7419.520.019.520.0
16 AWG1.3113.514.022.013.714.622.5
1.5 mm$^2$1.512.112.219.1612.112.219.1613.313.713.313.7
14 AWG2.088.458.7813.88.628.9614.18.79.248.619.25
2.5 mm$^2$2.57.417.5611.497.417.5611.497.988.217.988.21
12 AWG3.315.315.538.715.435.648.885.485.815.535.94
4 mm$^2$4.04.614.77.184.614.77.184.955.094.955.09
10 AWG5.2613.3433.4765.4793.4093.5465.5893.453.663.483.73
6 mm$^2$6.03.083.114.793.083.114.793.33.393.33.39
8 AWG8.3672.1022.1633.4462.1442.233.5152.182.332.182.35
10 mm$^2$10.01.831.843.081.831.843.081.911.951.911.95
6 AWG13.31.3231.3632.1681.3481.4032.2111.381.461.391.49
16 mm$^2$16.01.151.161.911.150.161.911.211.241.211.24
4 AWG21.150.83150.85591.3630.84810.8821.390.8650.9180.8730.937
25 mm$^2$25.00.7271.20.7270.7341.20.780.7950.780.795
3 AWG26.670.65950.67881.0810.67270.69961.1030.6860.7280.6990.744
2 AWG33.620.52310.53840.85740.53350.55480.87450.5470.580.5540.595
35 mm$^2$35.00.5240.8680.5240.5290.8680.5540.5650.5540.565
1 AWG42.410.41460.42680.67980.4230.43980.69340.4340.460.440.472
50 mm$^2$50.00.3870.6410.3870.3910.6410.3860.3930.3860.393
1/0 AWG53.490.32870.33670.5390.33540.34870.54980.3440.3570.3490.374
2/0 AWG67.430.26080.2670.42750.2660.27660.43610.2720.2840.2760.3
70 mm$^2$70.00.2680.4430.2680.270.4430.2720.2770.2720.277
3/0 AWG85.010.20690.21190.33920.2110.21940.34590.2160.2240.2210.238
95 mm$^2$95.00.1930.320.1930.1950.320.2060.210.2060.21
4/0 AWG107.20.1640.1680.26890.16730.17220.27430.1720.180.1750.189
120 mm$^2$120.00.1530.2530.1530.1540.2530.1610.1640.1610.164
250 kcmil127.00.14160.14730.23220.1460.1250.1490.159
150 mm$^2$150.00.1240.2060.1240.1260.2060.1290.1320.1290.132
300 kcmil152.00.1180.12270.19350.1210.1260.1230.133
350 kcmil177.00.10110.10520.16590.1040.1080.1060.114
185 mm$^2$185.00.1010.1640.09910.10.1640.1060.1080.1060.108
400 kcmil203.00.088510.091090.1450.09110.09480.09280.0997
240 mm$^2$240.00.07750.1250.07540.07620.1250.08010.08170.08010.0817
500 kcmil253.00.07080.072870.11610.07290.07580.07430.0798
300 mm$^2$300.00.0620.10.06010.06070.10.06410.06540.06410.0654
600 kcmil304.00.0590.061350.096730.06130.06380.06190.0664
700 kcmil355.00.050570.052050.082910.05250.05470.0530.0569
750 kcmil380.00.047210.048580.077380.04910.0510.04950.0531
400 mm$^2$400.00.04650.07780.0470.04750.07780.04860.0495
800 kcmil405.00.044250.045540.072510.0460.04780.04640.0499
900 kcmil456.00.039330.040480.064480.04090.04250.04130.0443
500 mm$^2$500.00.06050.03660.03690.06050.03840.0391
1000 kcmil507.00.03540.036430.058040.03680.03820.03710.0399
630 mm$^2$630.00.04690.02830.02860.04690.02870.0292
1250 kcmil633.00.028330.029150.046430.02950.0306
1500 kcmil760.00.02360.024290.038690.02450.0255
800 mm$^2$800.00.03670.02210.02240.0367
1750 kcmil887.00.020230.020820.033160.0210.0218
1000 mm$^2$1000.00.02910.01760.01770.0291
2000 kcmil1013.00.01770.018220.029020.01840.0192
2250 kcmil1140.00.01560.01560.0255
1200 mm$^2$1200.00.02470.01510.01510.0247
2500 kcmil1270.00.0140.01440.0229
1400 mm$^2$1400.00.01290.01290.0212
2750 kcmil1393.00.01260.01260.0209
3000 kcmil1520.00.01170.0120.0192
1600 mm$^2$1600.00.01130.01130.0186
3500 kcmil1770.00.01010.01040.0166
1800 mm$^2$1800.00.01010.01010.0165
2000 mm$^2$2000.00.0090.0090.0149
4000 kcmil2030.00.00880.00910.0145
4500 kcmil2280.00.00790.00820.013
2500 mm$^2$2500.00.00720.00720.0127
5000 kcmil2530.00.007150.00740.0117
3000 mm$^2$3000.00.0060.0060.0099
3200 mm$^2$3200.00.00560.00560.0093
3500 mm$^2$3500.00.00510.00510.0085