Determining 100V Wire Sizes & Run Lengths

Are you confused about what cable size to use in 100V PA installations?

Use the handy table below to get an approximate idea of the minimum cable size you need to use—simply find the Distance you need to run in the column that best matches the Power of your system. This is the minimum cable size you need to run for your system.

Alternatively if you already have cable and want to know the maximum run and power it can handle start with the Cable size and read across to Power and Distance values.

Cable Size Ω / 100m Maximum cable length against System Power
Wire section AWG 125W 250W 500W 1000W
13.3mm2 6 25Ω 4,367m 2,180m 1,086m 539m
6.6mm2 8 49Ω 2,177m 1,087m 541m 269m
5.3mm2 10 62Ω 1,727m 862m 429m 213m
3.3mm2 12 99Ω 1,087m 542m 270m 134m
2.1mm2 14 157Ω 683m 341m 170m 84m
1.3mm2 16 249Ω 430m 215m 107m 53m
0.8mm2 18 398Ω 269m 134m 67m 33m
0.5mm2 20 628Ω 171m 85m 42m 21m
0.3mm2 22 989Ω 108m 54m 27m 13m
Resulting line impedance 80Ω 40Ω 20Ω 10Ω

Results are for a signal loss of 1dB. For 3dB loss, muiltiply the maximum lengths by 3.5