- Jan 5, 2020
- Reaction score
yeah pencil and paper was only $350... though we're supposed to get a $25 refund if we sign up before January...not sure that's a great consolation prize for getting jerked around for a year, but whatever!WOW! CBT is expensive $375 + tax.
A is definitely incorrect. zero sequence currents and voltages are equal in magnitude and angles. If C is incorrect, then A is incorrect. it shouldn't matter if they are currents or voltages.@Tim @ NCEES I believe there is a typo in the sample. Referring to question 12:
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Answer given in the book:
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Symmetrical Component section from the reference handbook:
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I believe the answer should be (B, D), excluding (A). Option A states "The three zero-sequence current phasors are equal in magnitude and displaced by 120°." The solution states "Options (A) and (B) are correct, by definition from the transformation matrices shown in the [reference handbook]." However, if we look at the section in the reference handbook, we can clearly see that the zero-sequence current phasors (even though only voltage phasors are specified) have no displacement. Option A would only be true if it said "The three zero-sequence current phasors are equal in magnitude and are in phase." Or "The three zero-sequence current phasors are equal in magnitude and displaced by 0°" It would also be true if it said "The three positive-sequence current phasors are equal in magnitude and displaced by 120°."
However, I have been wrong before. If anyone notices that I missed something please let me know.