Short question about graphing AC voltage before rectificaiton

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Discussion Overview

The discussion revolves around the graphing of AC voltage before rectification in a circuit, focusing on the correct representation of voltage pulses and circuit connections. Participants explore the implications of wiring configurations and voltage definitions in the context of a full wave bridge rectifier.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that when considering VP to the ground, only the negative pulse should be drawn.
  • Another participant counters that VP to the ground is actually the positive pulse, recommending solving the circuit for various voltages.
  • A different participant points out that RL should connect to the rectifier junction, indicating a misconnection in the original diagram.
  • Some participants agree on the wiring issues in the diagram, with one noting that a previous post had a better wiring representation.
  • One participant acknowledges a mistake in their connections and shares a revised diagram, reiterating that VP starts from the negative input.
  • Another participant explains that VP would only be negative if the transformer secondary were out of phase, asserting that without explicit dot notation, the secondary is assumed to be in-phase.
  • A participant expresses confusion about the voltage orientation, stating that VP must always be higher than the Earth connection to avoid a short circuit.

Areas of Agreement / Disagreement

Participants express differing views on the correct representation of voltage pulses and circuit connections, indicating that multiple competing perspectives remain unresolved.

Contextual Notes

There are unresolved assumptions regarding the phase relationship of the transformer secondary and the implications of the circuit's wiring on voltage definitions.

Femme_physics
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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.
 
I think RL (and not its end where you have written "K") should return to the rectifier junction where you have Earth wrongly connected.
 
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 :)
 
Hi FP :smile:
Your full wave bridge rectifier connections look much better.

VP starts from the negative input
http://img525.imageshack.us/img525/927/ppppv.jpg
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
 
Last edited by a moderator:
From some reason I always thought that it's the other way around...

http://img838.imageshack.us/img838/9165/oppositenormal.jpg

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:
Femme_physics said:
But you're my source, Quab, so I'll amend my ... Much appreciated
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:
Femme_physics said:
From some reason I always thought that it's the other way around...

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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