A question about a three-phase circuit

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    Circuit Three-phase
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Discussion Overview

The discussion revolves around understanding the calculations and relationships in a three-phase circuit, specifically focusing on the magnitudes of currents and their phases. Participants are exploring the implications of phase angles on the addition of currents and the relationship between apparent power and voltage.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about adding currents I₁ and I₂ without considering their different phase angles.
  • Another participant suggests that the apparent power S1 and voltage V1 are similar in phase, implying that their ratio yields a magnitude only on the real axis.
  • A participant acknowledges a misunderstanding regarding the phase of I₁ and I₂, indicating that they believe the phase becomes 0 for both, which they recognize as incorrect.
  • There is a request for clarification on what "similar in phase" means, noting that one load has a leading power factor while the other has a lagging power factor.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus, as there are differing views on how to handle the phase angles of the currents and the implications for their addition.

Contextual Notes

There are unresolved assumptions regarding the definitions of phase relationships and the implications of leading versus lagging power factors on the calculations being discussed.

Shloa4
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I'll be happy for some help here.
Thanks. :redface:
 

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Shloa4 said:
For now, I am only focused on the magnitude.
So am I. :smile: You have added I₁ + I₂ without regard for their different angles.
 
oops.. :) but still, S1 and V1 are similar in phase, aren't they? And since that's the case, S/V yields magnitude only (on the real axis). Same for both loads. And since the phase becomes 0 for both I1 and I2 (which is wrong obviously, but I cannot figure out where exactly I miss a thing here) so I can add I2 to I1.
That's probably my problem here. Any idea?
 
What does "similar in phase" mean exactly http://img820.imageshack.us/img820/9631/icon5j.gif

The details are that one load has a leading pf and the other a lagging pf.
 
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