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Out of the curiosity, what kinda problem do you expect/anticipate that you will need to memorize this? I don't think I have seen any problems needing any of the info above. @akyip I know you mention in one of the previous posts that you did a lot of practice problems, did you ever use this info?

I am yet to see a breaker that is rated at 180A. (Maybe one day). However, I read the problem again and now I am curios to see if the problem says feeding 277V load or loads. If it's loads then you cannot round it up (we wouldn't meet 240.4(B) requirements) Practically speaking you want your...

I mean the answer states "Breaker Chosen". I don't see how can you chose something that does not exist. 

No exception taken? 😆

According to the NEC the 180A breaker does not existing.  I would chose C, 200A for my answer.

The trick here was to look for the exception for the existing building 110.26.(A)(c) which allows you to use condition 2, which is 4 ft.

That is correct, magnitude only because voltage drop of a circuit is in direct proportion to the resistance of the conductor and the magnitude of the current

 You don't need to use the angle for your calcs. If you have NEC Handbook I highly recommend looking at the examples in chapter 9, right after table 9.

I do not have code in front of me right now but I believe it's section 240 something that talks about overcurrent protection.  My understanding is that overcurrent protection protects both conductors and equipment.  It will protect a circuit by opening when current reaches a value that would...

Now that the exam is computer based I was wondering if anyone knows on any limitations on how many times one ca take the exam?

Good luck! 

That is correct however, in that case they wouldn't be able to offer B as a answer (IMO). I am of the opinion that code questions that do not involve any math "tricky" one. Here is a tricky example NEC question: — Electrical equip. is being replaced in the existing building. What is the...

I hear you but that is the NEC for you my friend. Like I said in my original post, have to look for clues in the question. The purpose of this question is to make you go to code and look at it (the answer taken straight from code) instead of going with you intuition.  

This question is pretty straight forward for someone who uses NEC on daily basis. I would look for clues in the question here it is "two motors" and non continuous part. It can also very much be  service factor,  temperature rise, start the  motor (check out 430.32(C)), duty cycle etc...

@DuranDuran that is an excellent point! I do not know why I simply assumed it was 3phase.

@akyip That's exactly what I did, I converted the xfmr impedance to 100MVA base and just added them. I just wanted to pick someone else's brain to see if they would think of going for the MVA method on such a problem.

I am wondering if problem below can be solved using MVA method? Can we assume that Sbase is the actual value of S? A customer is to be served from a 50 MVA, 115/13.8 kV transformer which has an  impedance of 7.5% on a 50 MVA base. The 115 kV bus has a system equivalent  impedance of 1.5 +...

I think you are misreading the code, it says " a sing le motor used in a continuous duty application". If you go back to Article 100, a continuous load is defined as one where the maximum current is expected to continue for three hours or more. There is no mention of a specific time period with...

I was always told that if the question calls out for Design (ie. B,C,D) always go to table 430.251(B)

Did they add any formulas for saturation current or any diode equitation ?