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Short question about graphing AC voltage before rectificaiton

  1. May 27, 2012 #1

    Femme_physics

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    Last edited by a moderator: May 6, 2017
  2. jcsd
  3. May 27, 2012 #2

    I like Serena

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    Hmm, Vp to the ground isn't the negative pulse.
    It's the positive pulse.

    Perhaps you should try to solve the circuit for a couple of voltages.
     
  4. May 27, 2012 #3

    NascentOxygen

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    I think RL (and not its end where you have written "K") should return to the rectifier junction where you have earth wrongly connected.
     
  5. May 27, 2012 #4

    Ouabache

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    I agree with Nascent about the peculiar wiring on this diagram.
    FP you actually indicate a better wiring in your 1st post of an earlier question :)
     
  6. May 27, 2012 #5

    Femme_physics

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    Last edited by a moderator: May 6, 2017
  7. May 28, 2012 #6

    Ouabache

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    Hi FP :smile:
    Your full wave bridge rectifier connections look much better.

    VP would only be a negative voltage if your transformer secondary were [itex]180^o[/itex] out of phase (as in dot notation of following figure) However, when they don't explicitly use dot notation, we assume the secondary is in-phase (What does that mean? what ILS also alluded, VP-to-Gnd is the positive voltage).

    scrcircuitxfrmroutofphase.jpg


    I don't see where you are taking the pull-down voltage into consideration. Perhaps you could say in you calculations [tex]V_{A-G}(max)[\frac{N_ב}{N_א}][/tex]
    http://i1131.photobucket.com/albums/m543/loxandbagels/scrcircuitwithpulldownxfmr.jpg [Broken]
     
    Last edited by a moderator: May 6, 2017
  8. May 28, 2012 #7

    Femme_physics

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    From some reason I always thought that it's the other way around....

    http://img838.imageshack.us/img838/9165/oppositenormal.jpg [Broken]

    But you're my source, Quab, so I'll amend my err and instead of the dotted line for VP I'll add a full line indicating there's a voltage there, and at negative wave there isn't. Much appreciated
     
    Last edited by a moderator: May 6, 2017
  9. May 28, 2012 #8

    Ouabache

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    Thank you for your faith in my comments. Though the nice thing about this forum,
    if I made an error, I am sure someone will 'politely' supply correction. :smile:

    So my username Ouabache is the French spelling of a native American word
    for the river that runs alongside my university in northern Indiana. (etymology)
     
    Last edited: May 28, 2012
  10. May 28, 2012 #9

    I like Serena

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    Regardless of the orientation, opposite or normal, Vp always has to be higher than the earth connection (0 V).

    If Vp were lower than the earth connection, you'd have a short circuit.
     
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