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I'm looking for advice on what type of wire and size of wire to use to create an outdoor 120 volt outlet that is 1000 feet away from my home. The device I'm going to plug in will pull a maximum of 80 volts and 3 amps. I do have options in my electrical panel for both 120 volt and 240 volt circuits. I'm also open to copper and aluminum options.

T

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    Have you thought about using transformers to Jack the voltage up and back down this will allow smaller wire to be used, I have a ~500’ run and the transformers (much larger than you need) allowed my total cost to be reduced.
    – Ed Beal
    Nov 13 '20 at 15:51
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    This may also be a situation where a stand-alone system - e.g., solar + battery may be practical. Is this 80V x 3A = 240W 24/7? Or is this something that will run for an hour a day? Makes a big difference. Nov 13 '20 at 16:25
  • The telecom equipment will run consistently 24 hours a day.
    – Eric
    Nov 13 '20 at 18:42
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    Which country are you in? (national rules differ). Please link or name the specific device. (there are tricks that work with certain devices but not others). Do you need to use the receptacle for other stuff from time to time? (that's a big deal) Nov 13 '20 at 20:43
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    Surely the device isn't expecting to actually get 80V from a wall plug -- nowhere in the world uses that. Most likely it's saying 80V is the minimum it will tolerate (which happens to be a 20% margin under Japan's 100V nominal), and when supplied with that it will pull 3A. But what is the maximum voltage it can handle? Most devices sold with a voltage tolerance that goes down to 80V will also accept up to 250V without issue -- and will draw much less current at that voltage. If that's the case, it'll make things much easier -- can you double check the device's specs?
    – Nate S.
    Nov 13 '20 at 22:07
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The part of the question about the dequipment "pulling" 80V doesn't quite fit, what you really need to know is it's utilization of the 120V supply - how many amps does it from the 120V receptacle. If this equipment converts it to 80V internally, that's not really relevant.

Assuming the device uses 3A at 120V, you could use #6 aluminum with less than 5% voltage drop at 1000'. Direct burial cable will probably be your best bet. However voltage drop is load-dependent; if someone plugs in something that draws more power, it would see more voltage drop.

That is an expensive wire purchase but it would be even more for copper. You'll have to plan to splice the aluminum to more normal sized copper at the end. You can do things a little more complicated, like supply a transformer at the receptacle with a 240V, which will allow a smaller wire, or step up to an even higher voltage and back down at the receptacle, but at these distances and loads it's not likely to be worth the trouble.

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  • Definitely the brute force way. #6 Al can be spliced to #14 Cu using a MAC Block Connector. Nov 13 '20 at 20:27

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