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Basic electricity

  1. May 22, 2006 #1
    I would like to know the diference between, volts,amps,watts,and ohems.
    I would like to know how to convert one to another. what I am tying to find out is I have 200 amp service breaker box, how many rechageable batters ,and what voltage do I need. I would also like to know what volt battery would it take to run a 60 watt light bulb. if you could tell me the math equations to convert from anyone of these to a nother
  2. jcsd
  3. May 22, 2006 #2


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    Staff: Mentor

    Volts, amps, and ohms are different things and don't get converted between each other. It doesn't sound like you have anywhere near the understanding of electricity required to be screwing with your electric power system.
  4. May 22, 2006 #3


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    :bugeye: :eek:
    Shocking, don't try anything to built with your knowledge of electricity

    Here are the basic formulas:

    U = R x I

    P = U x I

    But i hope you wouldn't assemble anything, because with your knowledge of Electricy it will end in a katastrophe.

    regards from germany


    hope my english is not too bad.
    My knowledge of electricity is not as bad, but my english! So if you notice gramatical mistakes please improve me.
  5. May 22, 2006 #4


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    Staff: Mentor

    I googled basic electronics tutorial, and here's the first hit:


    And I agree with the others -- do not mess with any AC Mains circuits until you have a much better understanding of electricity. Any voltage over about 42V is considered hazardous. AC Mains voltage in the US is 120Vrms, and is even higher in Europe.
  6. May 22, 2006 #5


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  7. May 26, 2006 #6
    Thanks for the advice.Found out there is a friend of the family that under stands what I am trying to learn. From what you all have said I need to spend some mega time with him and his sistom before even thinking about trying anything. The goal I am trying to reach is to create a total electic home powerd by solar, and wind power charging batterys. so thanks again for everyone input and consern for my safety.
  8. Jun 7, 2006 #7
    looks like that would be a long long journey to go. god speed.
  9. Jun 11, 2006 #8


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    Science Advisor

    Richie - creating an off-the-grid home or one that is grid connected so you can sell back excess power or use power on periods of sustained inclement weather is becoming slowly more popular. (selling back excess varies by state laws)

    The reason its only slowly becoming more popular is that you need $20k+ and 20+ years to make it become a financial break-even. If you're in an area with lots of sun at a steep angle (like AZ) then you probably need air-conditioning and would want high efficiency glass windows. If you're in MN with little sun and at a shallow angle, you need lots more solar panels.

    One big problem is that solar energy requires large surface area, and the solar panels use the same raw material as computer chips. Therefore it costs a lot of money to cover a large area and they are in short supply now because the plants to produce the raw materials are not all online yet and European countries have setup tax incentives for their citizens to install solar that increased demand on top of the existing situation.

    One big problem with wind is the power is affected by the speed to a cube, so a 20mph wind has 8x the energy of a 10mph wind. So again, the mean wind speed might require a large windmill to generate enough electricity to store up for the non-windy periods.

    A problem common to both is the intermittent nature of either in most areas.

    If you're land includes a large elevation change and a water source, micro-hydro is a much more user-friendly solution that can generate a large amount of power at all hours of the day.

    Oh, and you need large truck batteries, a special charger, an inverter (takes battery voltage and converts to household) and so on. There's lot of resources online, just type in solar and you'll get lots of good reading.

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