# is it posible to have a extension cord go over 1 km?

I'm asking this because I have a camper and its going about 1 km away from the house and I don't have a gas generator. I need power for the camper. How much gage wire would I need to make this happen?

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8 years ago
It is possible, but not very practical. Current loss is going to be your worst problem. And unless you already have 3-ought wire or bigger, and 1km of it you will be much better off spending the money on the generator. Another note: 1km of wire that can handle the current for that distance is going to require alot more than one guy and a truck to handle it! Have fun...
8 years ago
Could you amp it up at several segments of the run?
8 years ago
For every force, there is a counter force. With that said, anything else you add to the already heaping pile of cable, is just more weight and expense. I'd look for a different solution, for real!
lemonie8 years ago
You could do it, but it's not the best way. Find alternative. L
acidbass8 years ago
yes it possible but don't expect any power if you plug it in
kelseymh8 years ago
No. As "plumber_bob" wrote, current loss (or equivalently voltage drop) due to resistenace is the issue.

I found (Google "extension cord resistance) a nice posting online with the requisite data (so I don't have to compute it myself). The voltage drop was computed assuming a full 15 amp load.
`Wire size     R/1000ft      dV/100 ft16 AWG        5.29 ohms     15.9 volts14 AWG        3.14 ohms      9.4 volts12 AWG        2.05 ohms      6.0 volts10 AWG        1.29 ohms      3.9 volts 8 AWG        0.809 ohms     2.4 volts  6 AWG        0.510 ohms     1.5 volts`

Voltage drop (like resistance) is linear with distance, so you just multiply the voltage drop listed by the number of hundred-foot lengths you have. It's also linear with the current load, so a lower current will result in less voltage loss.

1 km = 3281 ft, so a standard 16AWG extension cord (those nice orange outdoor ones) carrying 15 amps will drop 521.7 volts over 1 km. Since that's much more that the original input voltage (117 VAC), you won't get any power out the far end. It'll all be dissipated in the form of heating up the extension cord.