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-   -   Transformer concept (https://www.askmehelpdesk.com/showthread.php?t=761763)

  • Aug 7, 2013, 11:07 PM
    abhishek er
    Transformer concept
    If I generate 1 volt a.c. and with a 1:240 transformer , I step up it to 240 volts then can I lit a 100 watts (240 volts , rated) bulb at its full intensity, from the output terminals?
    If not then why? What are the parameters limiting this to happen? The windings, wires? source? Or what? Please help





    I don't have a new transformer, but tried this with a rusting transformer (10:400), and 6 volts ac adapter at l.v. side but it did not lited up the bulb. So any one hellllllllppppppppp
  • Aug 8, 2013, 05:07 AM
    ebaines
    In theory it would work, but remember that the power needed for the light bulb must come from your source. For example if your light bulb draws 100 watts of power then your source must provide that 100 watts, which means it must deliver 100 amps of current at 1 volt (since power = volts times amps). Obviously this requires a pretty substantial voltage source plus a very heavy duty transformer with windings able to handle this very high level of current.
  • Aug 8, 2013, 07:58 AM
    abhishek er
    Thanks man,
    But if I'm still not clear may your answer to this question may help.

    Question. Suppose I connect a 1 volt dc battery to a 0.01ohm resistance then it would draw 100 amp of current, then what's wrong? And how can I increase the current flowing capacty in the battery? And if I increase it then will it be able to supply that much current?

    Sory if you think, me a question machine, who keeps going on.
    But you will be appriciated for your help.
  • Aug 8, 2013, 02:56 PM
    ebaines
    Yes - if you placed a 0.01 ohm resistor across the two terminals of the battery in theory it would deliver 100 amps of current. In practice a household battery is incapable of delivering such a high amount of current, so the battery's output voltage drops below 1 volt under such heavy draw conditions. Batteries are typically rated in terms of amp-hours, which is a measure of how many hours they can supply a given amount of current at the rated voltage. A typical 1-1/2 volt AA battery can deliver a max of about 500mA for about two hours. If it could deliver 100 amps it would do so for about 30 seconds before being totally drained. Carrying this amount of current would require a wire of at least 6 AWG in size - anything smaller and the resistance of the wire would cause I^2R heating that would suck most of the energy available. And of course since an AA battery delivers DC current, not AC, the transformer won't work with it to convert the voltage.
  • Aug 9, 2013, 12:43 AM
    abhishek er
    Thanks this helped.
    Well my second question was just to clear the concept, I know that transformer works only on ac.

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