Search results

Hello all, I am wondering if anyone has the EE Power Reference Manual by Camara that they'd be interested in selling? It looks like this. Please send me a message if you have one in good condition, I will pay via Paypal or similar secure means. Thanks!

I want to post a big thank you to everyone who is involved in this forum. This forum has been a tremendous benefit for my studying as a way to check 'official' book answers and also a way to better understand the various sample problems I've run across. There are many times that I was stumped...

This is a basic question about protecting a transmission line. If there's a fault at point D and breaker 5 fails to trip, which breakers should trip next? I would pick 2 & 4 since they are the next ones up-stream. If 2 & 4 fail to trip, then I would say 1 & 3 should trip. The...

We've found a llot of errors in this test over the last month and many have not been publicized by CI or corrected by via a formal errata. I'd like to list or link to changes that we have determined are necessary. This way all forum members can easily see what is wrong with this test. Please add...

This problem specifies a synchronous 3phase generator rated at 50kVA, 230V with per unit reactance of X'd= 0.4. With analysis performed at rated values, what is the magnitude of the transient current? The solution uses: Vbase = 230V Sbase = 50kVA I base = 50/ (sqrt (3) * V) = 125A then 1)...

Hi, I'm hoping this is a quick one to explain. This problem has a 6.6kV utility service with source impedance of 0.94%. It is connected to a transformer serving a building at 480V. The transformer has 4.25% impedance and rated current of 1,720A. It asks for Isc at the transformer's secondary...

Hi, I got to thinking about the exam and realized I have no idea how many people across the country annually take the EE power exam. I did some searching but couldn't find even a tidbit of info. I am also interested to know how many people are licensed electrical PEs. Has anyone come across...

Just a FYI for all- I recently took both of these within a couple of days of each other. I nailed the CI test with >85% over the 80 questions. The NCEES test I got 73% right. Lesson here- if you're studying from this CI test be aware that it is a bit easier than the true NCEES test. Good luck...

Hopefully another easy one. I understand the math that produces the answer. But isn't the 2291 MVA answer the total short circuit MVA on the 230 kV bus? The problem asks for the MVA contribution from just G1. Am I thinking about this wrong?

I haven't seen a thread on this problems yet. I hadn't heard of charging current before so I think this is an easy answer. Here goes the lob. For this transmission line problem finding Deq and C are straightforward. Finding Xc you use Xc= 1/(2* pi * f * c). So far so good. Now where does the...

Sorry for the NCEES blast, it has been a busy day. Before taking the practice test I hadn't looked much at autotransformers. Now I'm trying to figure out these 2 problems and realize that my resources don't spend much time with autotransformer equations and have no examples. I thought I...

This is the first voltage drop problem that I've seen where there are multiple sets of parallel conductors. I sat there thinking about it for a good while but eventually determined that the the impedance for this problem would be half that for a single run of conductors, but that was purely by...

Hi, I'm looking at the 'electric shock & burns' topic that is listed on the exam specifications. This is really not covered by the EERM. I have some reference tables from NFPA 70E but don't know what else is likely to show up on the test. Anyone have insight into what might be helpful for...

This comes from CI Variation 1 #49. It states that in a power flow study a slack bus typically doesn't have a fixed voltage angle or magnitude. I haven't come across this term in any of my review books. Can anyone explain it? Have I missed a major topic in my review work and now need to panic...

Hi all, I know what relays are, but am not familiar with the different types or their common uses. This was brought to light in a Complex Imaginary question (variation 1, question #68) that mentions the following types: impedance, differential, overcurrent, and voltage. It says that impedance...

This is a simple problem with two 5kVA motors in parallel, one with PF=0.75 and the second with PF=0.65 both lagging. The question asks to find the total system power factor. The relevant answers are: B ) 0.69 C) 0.71 The right way to do this problem is find the complex power for each and add...

Hi. I want to make sure I 100% understand this answer. The CI explanation isn't enough. The solved problem states that synchronous motors of any frequency, current, or mechanical load should be run in an optimal zone of operation. This zone is: shaft rotation speed range above peak torque. In...

For 300kcmil, TW, 60 degree cable the question asks what's the largest allowable overcurrent device: A) 150A B ) 180A C) 200A D) 225A The allowable ampacity of the conductor is 190A from the NEC. However this is not a standard ampere rating per 240.6. NEC 240.4 (B ) allows you to round up...

Hi. I understand the basics of this question but don't feel 100% confident on the phase shift on the 4 types of transformer connections. My books don't seem to bother illustrating the phase shift either. I know a delta- wye has a 30 degree phase shift through it (but I don't know which side...

Hi all. I'm having a little trouble with #111 and trying to figure out if I'm approaching the problem wrong or what. It's a fairly basic balanced 3-phase delta load with identical source to line impedances on all phases. We're given a load line voltage (VAB), the impedance on a line, and the...