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I think, but could be wrong, that you size the neutral for the expected unbalanced/harmonic current in the Neutral.

Just want to confirm: on the test, if we're given a question that has a circuit < 100A and given cable with 75 or 90 C rating, we're supposed to use the 60 C column in 310.15(B)16 for the cable ampacity, right?

Yes.  For future reference, if you just Google "NCEES power #" with the problem number, you can usually find one or several threads on EB answering the questions that you have.   Have a look at this one, as well as the attachment.  They solve it using both PU method and MVA method.

Indeed.

When we use the equation, we usually know (assume) the PF of the load at the receiving end, but the power factor of the total circuit (load and cable) -- which would be "seen" at the sending end -- can only be truly be known if we know the complex impedance of the circuit (that is, of the load...

This is the conclusion I came to.  I figure the intent of the equation in NEC (and IEEE 141) is to approximate and simplify the calculation by working with "real" numbers and not worrying about phase angle (except that it's inherent to the power factor).   I was having a premature senior moment...

Oh!  It should be positive, since the value used there should be (θv - θi) = (0 - (-49.5)) = (0 + 49.5) = 49.5 In that case, the answers for (5.57 ∟ 49.5 V) and [C] (5.57 V) are closer to [A] and within reasonable tolerance for an "approximation" type of equation.  Still, are supposed to use...

I didn't use j in equations for B & C.  Also, the current angle in your calculation should be negative because it's a lagging circuit and I stated that the voltage phasor reference angle is assumed to be 0.  For ABC rotation, that'd make the current angle -49.5, right, or do I have something...

Perhaps the difference in the equations above is that (A) is the vectoral difference between the sending/receiving voltage phasors, whereas (B) and (C) are effectively the difference in the magnitude, as if the two phasors were superimposed on each other?

Necro'ing this thread.  I've looked at several other threads (on EB and Mike Holt forums) where this NEC Table 9 Note 2 formula is discussed, and I'm still slightly confused.   When using the Effective Z from the table (for 0.85 power factor) -- or when calculating a new Effective Z (for some...

This is something that's still a bit unclear to me.  I know, for sure, that there's a 30 degree phase shift through a XFMR, depending on the primary and secondary winding connections.   However, if we're working a problem involving complex numbers (and the angles are relevant to the problem)-...

You're referring to a simple paper folder with 3 brads inside to fasten paper, right?   The function you describe is what I'm looking for.  Wanting to put index and formula sheets in a smaller folder/combing to make it less cumbersome and not have to keep flipping to the front of my 3" binder...

I appreciate all the feedback.  Seems like one of those "better safe than sorry" kind of things. Anyone here know whether folders with brads are acceptable in lieu of big plastic binders?  Per the guidelines, I would think so, but just like the pencil mark issue, I wanted to check people's...

Thanks.  Perhaps if I feel bored I'll go back and highlight, but fortunately most of my notes are printed Adobe comments.  However, certainly seems like I should photocopy the several pages of practice problem solutions that I hand-wrote.  Sorry to resurrect a dead subject.

So far most of it will go in a binder, but I wanted to put some things like my note index, hand-written formula sheet, etc. in a folder with brads to make it more easily accessible.

I read on some website that any hand-written notes in our reference material needs to be in ink, not pencil, but I can't find that anywhere in the NCEES Examinee Guidelines.  Do I have to go back through all several hundred pages of my notes and trace any hand-written comments in ink?

I read on some website that any hand-written notes in our reference material needs to be in ink, not pencil, but I can't find that anywhere in the NCEES Examinee Guidelines.  Do I have to go back through all several hundred pages of my notes and trace any hand-written comments in ink?

It is 3-hole punched.  I'd just rather use something less bulkier than binders to bind everything together.  I just want to make sure other people have been able to use things like brads without any trouble.  The Examinee Guidelines specifically allow brads, but want to check others' experience...

I've got lots of various materials which I've printed and don't want to stick inside of clunky binders.  The Examinee Guide says that brads are an acceptable form of binding.  Does that mean these? https://www.amazon.com/Officemate-Round-Fasteners-Plated-99817/dp/B003DYZR6M/  Similarly...

Pass rate in April was 50.66%.  Pass rate in Oct-2015 was 50.37%.  Seems consistent to me so why would they try to make the pass rate lower?