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How shall I run electricity 2000 feet away from light pole?

  1. Jun 19, 2013 #1
    I'm trying to run electricity from one side of the my land (country side) to the other. Electricity is 2000 feet away from light pole. first 500 feet I'm running number 8 wire. for the other 1500 I'm running number 12 wire. I'm getting a power drop because of distance. Local electricians told me to buy a step up converter to run in between the distance. I'm only looking to get a good 120volts to keep everything running well. any suggestions on what I should get/do?
     
  2. jcsd
  3. Jun 19, 2013 #2
    Depends a great deal on how much load to intend to draw. Any idea of the amps?
     
  4. Jun 19, 2013 #3

    SteamKing

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    Yeah, get an electrician or let the power company run this line and provide the necessary equipment. If you turn yourself into a Roman candle, you won't have anybody to blame but yourself.
     
  5. Jun 20, 2013 #4

    sophiecentaur

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    Safety shouldn't be a particular issue as long as you use a suitable fuse and Earth Trip. (Also, avoid using the cable on the reel if you want to test the system - it can overheat)

    This length of run is problematical, I'm afraid, and would cost a lot, whichever way you want to do it. I bet your local 'professional' would love the job!!!.
    You really have to know the Current demand. The resistance per 100ft (or whatever) for standard wire gauges can be found on the Net an it will be easy for you to work out the total resistance of your cable run (times two because of the return trip!). (2000ft (doubled) of 8 gauge will be about 2.4Ω and, for 12 gauge, about 6.4Ω) See this link.
    The voltage drop can be worked out by multiplying the cable resistance by the current (ignore the fact that the current will be a bit less, due to the cable resistance; it will be a pessimistic answer and put you on the right side). For just 10A, you can expect to lose about 60V over your 12 gauge run!! Using 8 gauge over the whole length, the drop would be (pro rata) around 20V, which may not be too embarrassing.
    Unless you are dealing with no more than a couple of low wattage lamps, I would think you need to spend a lot more on cable. Imo, just putting in a transformer would not make sense, in such an extreme case as this.
    But the numbers count. I looked at the cost of cable and you would be talking in terms of quite a high cost. Commiserations!
     
  6. Jun 20, 2013 #5
    You can shop around for a "line interactive UPS". These will accept inputs as low as 90V and use an autotransformer to compensate. If you are powering a PC, you can get a cheap UPS that has good brownout range.

    Again, depends on your anticipated current. What are you trying to power?
     
  7. Jun 20, 2013 #6

    psparky

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    You said you are powering one light?

    So if you are just running a light.....I'm guessing 2 amps or 240 watts.

    2 amps at 2,000 feet with an 8 AWG wire will give you a voltage drop of 5 volts.....or 115 volts at the light.

    For a 5 amp senario at 2,000 feet....a 4 AWG wire will give a voltage drop of 5 volts as well.....or 115 volts at light.

    I don't really believe in voltage drops bigger than 3%....but that's because I'm in commercial buildings where bigger drops would not be tolerated. Perhaps out in the backwoods a 20 Volt drop would be acceptable. Don't forget you have to pay for that voltage drop as well....like lighting money on fire for no reason.

    Then again a 12 AWG wire costs $12 per hundred feet.....an 8 AWG cost $37 per hundred feet....and a 4 AWG cost $100 per hundred feet. Then you have to consider you need 2 wires plus ground so you are really looking at 6,000 feet. So if you use 8 AWG you are looking at over $2,000 in wire alone.....if you install it yourself. Plus the cost of conduit and digging the Earth. You are looking at at least $5,000 dollars to install a light. WOW! This must be one heck of a light!

    Perhaps another idea would be better....or perhaps consider solar powered light!
     
    Last edited: Jun 20, 2013
  8. Jun 23, 2013 #7

    sophiecentaur

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    @psparky
    Dang! you got there just before me with the solar idea! But, if solar would be sufficient, I have a feeling that the existing line voltage drop wouldn't be worrying him (i.e. the load would be very low)
    The solution really depends upon the specifics. The actual load and voltage drop are vital to know, before a proper solution can be arrived at. For lighting or simple electronic equipment, the cheaper solution could be some sustainable source combination (wind + solar). If the load is intermittent, a trickle charge (average current) through the existing cable could possibly be enough. Almost anything would be preferable to thousands spent on extra wire!!
     
  9. Jun 23, 2013 #8
    There is a really simple solution to this problem which would eliminate all concerns: get the power company to run the line, telephone poles, transformers, and all even if it costs $10,000. You see that way, you've done the job first-class and when we're doing work with electricity or gas, there is only one way to do it: first-class.
     
  10. Jun 23, 2013 #9

    SteamKing

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    How do you get a solar powered light to run at night?
     
  11. Jun 23, 2013 #10

    davenn

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    batteries solar charged during the day would be the usual way ;)

    Dave
     
  12. Jun 24, 2013 #11

    sophiecentaur

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    Solar powered torches never really did get off the ground until they sussed that one out. :biggrin:
     
  13. Jun 24, 2013 #12
    I do believe there already pole mount solar / streetlight solutons - try Petra Solar. Yes, no matter how you "cut it" 2000' of cable is $$.
     
  14. Jun 24, 2013 #13

    sophiecentaur

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    You can get quite a tasty low power solar solution for not many hundreds of quids.
    But we really need to know more of the actual situation and requirements.
    Hello - - - - - OP??
     
  15. Jun 26, 2013 #14

    vk6kro

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    Reading the first post, it sounds like there is already a power line in position. It is getting too much voltage drop, so it already exists.

    The question was how to make it more efficient.

    Local advice has said to step up the voltage, then step it down at the other end, which is classic power transmission technology and good advice.

    It would be good to get an electrician to install the transformers and to examine the transmission line for safety. You wouldn't want to start a bush fire or zap someone.
     
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