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I think the answer options are incorrect or problem is not worded correctly. In case of line to line fault, Ia1 = -Ia2 since there are no zero sequence components in line to line faults, the current in IA = i0+i1+i2 = 0 Feel free to correct if my understanding is not correct, I am going by the...

XHHW can be found in 75C and 90 C insulation.  This problem may have been solved using previous years code. According to 2017 code, does wet location mean 75C insulation? I have not been able to find that.  

This is a thread to ask NEC code related questions.  Example16: What is the ampacityto size the feeder conductor if it supplies the following two motors? 1.One 7.5-hp, 230V, single-phase motor 2.One 5-hp, 230V, single-phase motor Ans: Table 430.248 gives 40 A and 28 A as individual FLC of...

According to this what I told you would be correct. 

Hazardous Area Classification (NFPA® 497, 499, 30B) Are you buying these for the upcoming exam?  It's a 50 bucks a piece. An additional $150 on top everything else.  

Zach, What was in red font was by the author. Not sure about the source. We both get the same answer.     V_drop_1ø = IL/Zline           ϴi = cos-1(0.80)           ϴi = -37º when Vln is at a reference of 0º      V_drop_1ø = (30A<-37º)/(5 + j15Ω)      V_drop_1ø = 474.3V<35º I think...

I'm interested in knowing the logic though. The two methods would take the same time, it just that the method given with the problem is difficult to remember compare to ohms law. I understand the voltage drop per NEC, those types of problems are worded differently. They give you conductor size...

I did not answer your question keeping in mind NEC. I thought this was one of those questions where they just want to check your knowledge on what can happen when capacitor is added at the motor terminals. I will have to look into nEC code. 

A 3 phase 12 kV feeder supplies a load of 30 A at 0.8 power factor lagging. The line impedance from the 12 kV source to the load is 5 + j15 ohm. The approximate voltage drop (V) per phase is given by: (A)  1170 (B)   195 (C)  780 (D)  390 D For a three phase circuit, the voltage drop per...

I think their answer may be confusing you. The old transmission line impedance before the step up transformer was installed is 10< 30 on 13.2 KV Now the transformer is installed so transmission line will see 132 KV  You calculate new impedance using the new voltage Z new = Z old X (old...

Below are the NCEES topics related to motors.  I did not see any DC motors. Also, I do not see single phase AC motors. Induction and synchronous machines are AC poly-phase  motors and generators. Correct?  Does that mean DC motors as well as single phase AC motors are not included in the...

72 Amps. The apparent power and therefore current in the feeder/branch conductors should be less because the power factor has improved. Cable should still be rated for 72 A amps, as the capacitor fuse can blow and capacitor not working in which case it will draw the same current as before. I...

Generator parameters are 22KV, 500 MVA 500 MVA is the rated apparent power of Generator. So it can not supply more power than it's rating. I'm also confused by this simple problem. I have read somewhere MVA base and MW base are the same thing. So what that means is 0.8 PU real power would be...

We  need to know the zones to answer the question. 

Correct . Did you have the answer key to the question you posted? 

Okay so there are some keywords and on the 2nd thought here is how I would solve it.  Generator capacity does not equal load consumed. Load consumed depends upon the load. For e.g. You can have 500 MW generator but if load draws 200KW then that's what it is.  In this case, they are asking for...

They have given 0.8 PU real power(KW) and Power factor of 0.6.  Therefore the apparent power(KVA) is 0.8/.6 = 1.333 PU X 500 MVA = 666.666 MVA actual.   Does the above makes sense or is this correct? 

I have my hand written notes/ remarks on my binder pages in black ball pen. Hope it doesn't look like written with NCEES pencil. I wouldn't want to photocopy all these pages as it is too much work. I would think by now NCEES would know that people can use black ballpen and it looks similar to...

Mechanical pencils may be good for bubbling etc. If you have to quickly draw diagrams, solve problems etc may be hard to use especially if they don't give you a soft lead pencil such as 2B etc. I also find that the tips break easily. I haven't heard many people complaining so might be okay, will...

EB has links to topics such as ground resistance testing, instrument transformers, lighting protection , surge protection.  Many people are printing the reference material and putting it in their binder.  Do you think this really helps? the topics are so vast and hence the type of questioning...