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How far can step up transformer inflate voltage

  1. Jan 18, 2010 #1
    How far can a step up transformer increase voltage ? Why voltage is stepped up. Is the end result output power suitable for home use after using step up transformer ?
  2. jcsd
  3. Jan 18, 2010 #2
    voltage is stepped up to transmit in distant areas.When it is stepped up then value of voltage is increased but current value is decreased so (i^2*R) loss through wire is minimized .Generation company develops power & transmit through transmission line into sub station then sub-stations distribute it to the home users through distribution line.There are some catagories(in sub-station) ie:1KV,0.4 KV,though home users consume little power, they are connected with .4 KV.
  4. Jan 18, 2010 #3
    Thanks. If the generator is designed from scratch and it delivers 1200 volts then how to make it suitable for home use. How to calculate the wattage of home and adjust it to the generator output.
  5. Jan 18, 2010 #4


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    You just asked this in another thread

    To convert 1200 volts to 120 or 240 volts you need a step down transformer.

    To calculate the wattage your house uses just add up the wattages of all the appliances in the house.
  6. Jan 18, 2010 #5
    Thank you for your overwhelming replies ! My problem is that If I make a generator 240 volts and not 1200 volts, will it be suitable for home use ? How to determine whether it is suitable for home use or not ? How to calculate the power load. Like to my knowledge varied devices use varied amps. So you mean to say that if I produce generator 240 volts or 1200 volts (with a step down transformer) it is suitable for home use ! is it so ? I think the power load requirement calculation is the biggest deal here.
  7. Jan 19, 2010 #6


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    Assuming you supply the right voltage to the house, other necessary things are that the frequency is right (usually 60 Hz for 120 volts and 50 hz for 240 volts) and also that the generator can supply enough power at that voltage.

    On each appliance, you will normally see a plate that says how much power it uses.
    Maybe it is a coffee maker and it says on the label that it uses 840 watts at 120 volts. This is all you need to know, but you could work out from this that the coffee maker uses (840 watts / 120 volts) = 7 amps.

    So, if you work out all the power requirements of the things that could be used at once, you can just add up the powers in watts.

    In most houses there are a lot of things that just use a small amount of power like 20 or 30 watts. Things like computer modems or radios are like this. You can guess a bit with those, but big items like room heaters or washing machines you would need to read the label and get it right.
    Having done all that, you would probably double it so that the generator is not being heavily loaded all the time.

    Another thing you need to know is how much the generator voltage changes when you draw more or less current from it. It should be a fairly constant voltage out (and the right voltage) or the lights in the house will be changing in brightness when you turn on the coffee maker for example.
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