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Ok, so I got this problem figured out but the only thing I dont understand as to why....and this may be a stupidly obvious answer......is why did they us the sqrt3 * 12KV in the solution when solving the problem. Isn't 12KV already a line to line voltage in this wye type problem?

Ok so now my next issue with this problem is in the solution provided how did they determine that Ia(3phase)=Ibase(a)/(ZT1pu+ZLpu)? Is this a standard formula in the process of PU analysis that I(Actual) = Ibase/Zpu?

Ok I got it on the base value of 100 MVA but how are the PU impedances found?

Ok, so I suck a little at this Per Unit analysis stuff....... so can someone explain this problem to me? Why does the solution use 100MVA as a base? Thanks!

Anyone????

Ok this power meter thing is a bit confusing to me. Now looking at the answer in the back I understand it and why they would read the same a a PF of 1.00 heck I even guessed it was 1.00 before looking at the book. I just need some explaining done on the ins and outs of this problem as follows...

Ok so I have no notes or study material nor can I find any on the inner-net that explains the what how and whys of this problem. Can anyone on hear do this??? How are you suppose to know that the transformers will load in inverse proportion to there impedances?? .......Im lost. Thanks!

Anybody have any decent internet references for Magnetic Circuit Theory?

Nope you did good. Thats what I was trying to ask. No my next question is why do these NCEES guys have to be so sneaky in how they word there questions and make you just jump to assuming they want a Full wave bridge rectifier wave form from the load side?

I have been looking at this problem for a bit and still dont quite understand why they selected the answer A for the neutral current. The supply contains a full-wave rectifier bridge and it would make since that the current graph would look like choice B. I believe that choice B would be a...

Funny....I asked this same question in the thread you linked to......my brain is toast. So in other words we are treating the delta element of this problem as a black box and assuming its a wye element to make the calculations easier. I got it. Thanks!

In the solution for this problem it seems like they are solving this system as if its a Balanced Wye system and not a balanced Delta system because they are performing the calculation by solving for VAN in the first part of the equation. In a delta system isnt VAN the same as VAB?????

your a genius!!!!! Thanks!

Well I have started studying again........ and I have a question on this problem. (see attached PDF) In the equivalent Single Phase circuit why did they not add in the impedance of the Neutral line (1+j0.01)? Is this an error on the page or did they do this for a reason? Thanks! Power_prob.pdf

Thanks!!!

So the new power exam will have questions from the NESC as well as the NEC???? If so what versions the 2007 NESC and the 2007 NEC?? That means I have to spend another 300 in books just to take the new version of this test!!!!

They will start updating the database tonight. Some poeples names will appear in the database by saturday and some will get there letters on saturday as they are going out today. PELS has posted the pass fail percentages as well. It all depends on how close you are to SAC that determines if you...

Um...no im not making a fake results posting. Check the boards website. They have new as to when the results will be mailed.......Early February 2009 just like every other year.

WE SUCK! Mark your calendars for good old February!

Okay so if the frequencies of the two components were the same then the equation: (7/SQRT2)^2 * 3 would be true? However Since the frequencies are different we must use the equation: 3*(5/SQRT2)^2 + 3*(2/SQRT2)^2