American Wiring Guage

[one_and_only2004]

I haven't had much experience with this guage of cable.
i understand 8awg is smaller than 2awg, but if i run two 8awg cables in parallel is it considered to be 4awg?

[holdenboy]

Youve basically got the idea.

Heres a little table comparing AWG to square mm.

http://www.reuk.co.uk/AWG-to-Square-...-Converter.htm

[one_and_only2004]

Thanks lad, that makes it a bit easier to understand. damn the americans and their crazy units!

[holdenboy]

haha....yeah try walking into a welding supply store and ask for 0AWG cable, they look at you as if youre weird

[commsirac]

Thanks lad, that makes it a bit easier to understand. damn the americans and their crazy units!

Really the AWG scale is really not so 'random' as the rest of the imperial units that the Americans cling to.

Most are familiar with decibels, and how a 3dB increase represents a doubling of the acoustic power needed?

the awg works along the same logarithmic formula.
A decrease of 3 in the awg rating allows a doubling of current carrying capacity of the wire.
So no, two 8awg wires isnt equivalent to 4awg, it falls 20% short. Two 7awg wires is equivalent to a 4awg wire.

Its actually not a prudent exercise to use two smaller wires to replace a larger conductor. Unless the terminations are perfectly identical, one of the wires could easily end up carrying a higher proportion of the current than the other and overload that wire, just as putting two 20A fuses in parallel wont guarantee that the circuit will be able to pass 40A without a fuse blowing

[one_and_only2004]

all i was going to do was run a 8awg wire to my amp, but it needs about 44A instead of 40A so i thought i could balance it out with 2 8awg runs, because that's an accepted practice when running power cables in queensland if your load is bigger than what just one cable would do.