NCEES Sample Exam Questions (128, 509, 516, 518)

[GreenNGold]

I had a few questions on the NCEES exam and could not find them on this board. Hope someone can help.

1. NCEES Question 128. Does anyone have a good article about the volts/hertz ratio? Or can someone explain the relationship between the two and what happens when volts is increased and hertz is held constant and vice versa?

2. NCEES Question 509. Where is the 30deg coming from in the solution? Isn't Wattmeter 1 going to read (Vac*Ic*cos(load pf angle) and Wattmeter 2 is going to read (Vab*Ib*cos(load pf angle)?

3. NCEES Question 518. Do we multiple 208 by root 2 because it is asking for the value required to limit the PEAK charging current? If it did not say PEAK, would we just use 208V?

4. NCEES Question 516. Can anyone explain the solution in more detail? Particularly why the answer is A and not B?

I can post the questions if needed.

Thank you.

 

[knight1fox3]

^ just a quick word of advice which might save you some time, a number of these questions relating to the power exam have most likely been discussed in previous thread. Might not hurt to do a quick search before posting a question to see if you can an answer quicker. That said, see below.

1. NCEES Question 128: http://engineerboards.com/?showtopic=11900

2. NCEES Question 509: http://engineerboards.com/?showtopic=13816

3. NCEES Question 518: http://engineerboards.com/?showtopic=20198

4. NCEES Question 516: http://engineerboards.com/?showtopic=5495

Hope that helps.

 

[GreenNGold]

I had tried to do a search and must of missed those. Thanks, I appreciate it.

The 516 I have is a different problem though. It shows a thyristor circuit? Anyone have that problem?

I am going to have to do more research on the wattmeter method. I thought I had it down but that 30 degrees has me confused still.