PM Recomended Wire Gauges

American Wire Gauge (AWG) is the standard measurement of wire sizes in the US. The higher the gauge number, the thinner the conductor. Heavier gauge wire is required as either amperage or wire length increases. Overloaded wiring can negatively affect reliability and safety due to excessive voltage drop and heat. Wires thinner than 18 AWG are not recommended for vehicular use. The tables below provide general guidelines for choosing wire. Remember that common ground wires must be adequate to carry the total amperage on the circuit, even if separate hot wires are used. The data included here only illustrates general wiring principles. Variables such as the exact type of wiring used and the type of devices connected will effect the actual performance of any circuit. Always verify proper operation after installation.

Wire Gauge Specification

Gauge (AWG)

 Diameter (inch)

Diameter (mm)

Cross Section (mm2)

0000 .4600 11.68 107.16
000 .4096 10.40 84.97
00 .3648 9.27 67.40
0 .3249 8.25 53.46
1 .2893 7.35 42.39
2 .2576 6.54 33.61
3 .2294 5.83 26.65
4 .2043 5.19 21.14
5 .1819 4.62 16.76
6 .1620 4.11 13.29
7 .1443 3.67 10.55
8 .1285 3.26 8.36
9 .1144 2.91 6.63
10 .1019 2.59 5.26
11 .0907 2.30 4.17
12 .0808 2.05 3.31
13 .0720 1.83 2.63
14 .0641 1.63 2.08
15 .0571 1.45 1.65
16 .0508 1.29 1.31
17 .0453 1.15 1.04
18 .0403 1.02 .82
20 .0320 .81 .52
22 .0254 .65 .33
24 .0201 .51 .20

 

 

Wire Gauge Required for 3% Voltage Drop at 12 Volts

Circuit Length Total Circuit Amps
1 5 10 20 30 40 50
10' 18 16 14 12 10 8 8
20' 16 14 12 8 6 6 4
30' 16 12 10 6 4 4 2
40' 16 12 8 6 4 2 2
50' 16 10 8 4 2 2 1
60' 16 10 6 4 2 1 0
80' 14 8 6 2 1 0 00
100' 14 6 4 2 0 00 000
120' 14 6 4 1 00 000 0000

 

 

Wire Gauge Required for 10% Voltage Drop at 12 Volts

Circuit Length Total Circuit Amps
1 5 10 20 30 40 50
10' 24 18 18 16 14 14 12
20' 22 18 16 14 12 10 10
30' 20 18 16 12 10 8 8
40' 20 16 14 10 8 8 6
50' 18 16 12 10 6 6 2
60' 18 16 12 8 4 4 2
80' 16 10 8 4 2 2 1
100' 16 8 6 4 2 1 0
120' 14 8 6 2 1 0 00