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Apparently I woke up in the middle of the night last night, rolled over, asked my wife if I needed to divide by the square root of 3 then rolled back over still asleep. I think I was still trying to figure out some of the problems in my sleep...

I was planning on doing the same... but the closer the exam got the more nervous about it I got. After all this work I don't want to miss a question just because I'm cheap.

While we're on the subject, is it just me or does it seem completely ridiculous that "Code for the Manufacture and Storage of Aerosol Products" could potentially be on the exam. I struggle to understand how it's even related. The hazardous category stuff, sure. But aerosol cans? Really?

I think I'm going to leave both Art & Science of Protective Relaying (GE) and Blackburn at home.  I'm glad I'm not the only one finding them to be dead weight.

Can anyone recommend some good last minute protection practice problems? I've worked through the related problems in Power Systems Analysis (Glover), Power System Relaying (Horowitz), as well as the EngPro and Graffeo guides and the NCEES exam.  I found the EngPro exam and NCEES exam...

At this point that sounds good to me - a confidence booster for the last week!

I've actually never seen this site before. I'll be trying it out this weekend. Way to set the bar high with 100%. :)

I guess we can agree on the solution then: just remember 277<0  :)

@Drewism, where did R = 0.49 come from? It's R=0.29 in NEC table 9 and NCEES solutions.

Thanks for the input.  The difference in angle didn't turn out to be irrelevant for me - when I solved the panel A equation with 277<-30, the panel A voltage ends up about 2V higher, which was enough to get the question wrong.  I just cant wrap my head around this one.

All, A quick question about #129 in the NCEES practice exam. This is a voltage drop problem with a main distribution panel (MDP) feeding another panel, Panel A. The problem gives the MDP voltage as 480V, a load current of 400A with power factor 0.80, and provides cable details for the 250'...

Dan Hart's book appears to be exactly what I was looking for! Thanks @Drewism!

Good morning, Can anyone please recommend references for power electronics? Inverters and rectifiers (specifically 3 phase) are definitely a weak spot in my understanding and references. The references I've found online thusfar seem to get too detailed for what is needed for the PE exam. I'm...

All, Sorry to dig up an ancient thread, but it appears more practical than starting anew. The NCEES solution for this problem includes: VpanelA = 480/sqrt(3) <0 - 5.6<22.0 = 271.94<-0.44 V Why is it 480/sqrt(3)<0 and not 480/sqrt(3)<-30? Doesn't the conversion from phase to...

Thanks everyone for the detailed answers. After doing a detailed review,  I think my confusion is in the difference between complex power (magnitude and angle) and apparent power (magnitude only).  The way I now understand it: - I don't need to take the conjugate when working with S= sqrt(3)VI...

All, I have what I think may be a really basic question but it keeps tripping me up. When is the conjugate of the current used with the formula S=VI*? The 3 phase equations S=sqrt(3)VI and S=3VI don't seem to use the conjugate, but I don't know why. I've also run into some single phase...

Zach, Thanks so much  - that makes sense, and I never would have figured it out on my own!

I'm having trouble determining when to use the complex voltage drop equation including cos and sin, as used above. For example, the CI problem above uses Rcos and Xsin. However, similar CI voltage drop problem 4-19 doesn't. It just multiplies the values from NEC table 9 by the current. Is...

Glad you had the same reaction as me - I'm assuming its an error in the solutions. Just needed a sanity check.

This problem gives the following information regarding two parallel transformers: Impedance of T1 = 5.25%, Impedance of T2 = 4.75%, total current =11,500A. The question then asks for T1's current contribution. I get: I = 11500*(0.0525/(0.0525+0.0475) = 6037.5A However, the answer provided...