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Secondary voltage on transformer

  1. Aug 15, 2013 #1
    120 v ac primary and turn ratio of 5:1 I came up with 600v ac is this wrong
     
  2. jcsd
  3. Aug 15, 2013 #2

    phyzguy

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    Which is the 5 and which is the 1?
     
  4. Aug 15, 2013 #3
    5:1 ratio on secondary 120v ac primary x5 /5 = 24v secondary
     
  5. Aug 15, 2013 #4

    phyzguy

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    Sorry, I don't understand. Is your question answered? If so, great. If not, I still don't know whether the primary has 5X more turns than the secondary or vice-versa.
     
  6. Aug 15, 2013 #5

    vk6kro

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    If you had a transformer which had two windings with a turns ratio of 5 times as many turns on one winding as the other, and you connected 120 volts across the larger winding, you could get 24 volts across the smaller winding.

    If you connected them the other way around, you might get 600 volts.

    A complication you need to know about is that the winding with 120 volts across it needs to have enough inductance to stop a large current flowing in that winding.
    Otherwise, the transformer could be destroyed.
    A rough guide for small transformers is that there should be about 5 turns of wire for each volt put across the winding.

    So you can't just have 5 turns and 1 turn and have it work at 120 volts.
     
    Last edited: Aug 16, 2013
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