NCEES Power Afternoon Sample Question 505

I'm looking at this NEC code question and scratching my head.

I am using NEC 2005 and Table 430.151B referred to in the solution is no longer there.

So, obviously this must have changed since NEC 2002 publication.

Then, I find an equivalent Table 430.251B in NEC 2005.

However, there is no mention of Polyphase Design E motors at all in the Table.

Help me sort through this madness.

Question 1: Am I looking in the right place? At the risk of sounding ignorant, are Design E squirrel-cage motors not taken into account no longer?

Question 2: If this question is worded such that it is not valid for the current NEC code, then hypothetically what would you suggest a change in the wording to make it into a legitimate practice exam question?

Question 3: Also, is the additional info: 60 Hz, 52A, 0.87 lagging PF at full load all red herrings (i.e. not needed?)

Thanks

Don't feel bad, I wasted a lot of time on this problem when I was studying too. Design E motors were removed from the NEC in 2005. The NEC Handbook has a note in it that says so. I did a little research and it sounds like they were a special type of high-efficiency motor that never really caught on. Perhaps someone else here can explain more.

I don't have a copy of the NEC or the problem to help you modify the question to make it useful. Perhaps someone else can. If I recall correctly, it was just a look-up type problem--if you could find the table you reffered to, you could pretty easily answer the question. I think you just needed to know whether to round up or down.

As for the extra info--many of the PE questions, especially the motor ones IMHO, give you extra info that is not relavent to the question. Again, I don't remember the problem exactly, but all the information you mentioned is probably unnecessary to answer the question.

mudpuppy, thanks for clarifying. You're right, if it was still valid, the question is merely a lookup question. I hope there are some of these simple types on the actual exam!