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Can anyone help me out with Q21. I am not sure if I understand this correctly. On generator we can measure the terminal voltage. So when operating at full load we take 1 pu as the terminal voltage and hence we calculate internal voltage using the E0 = Ex + E formula. So at full load we have E as...

Can anyone help me with this question? I am not sure if I understand the tap setting correctly. I am not quite sure what is restraining winding tap setting. I am assuming that because the two currents (4.8A and 8.3A) on the two sides of the relay are not equal, so there is another CT to make the...

Can anyone explain to me the 9.2t. I am so confused about the distance relay topic.

Can someone explain to me where 3337 comes from?

I have a question. If a single-phase transformer is given rated power, rated voltage, resistance, and reactance. Why is voltage^2/ (resistance+reactance) not equal to the power? If the question asks to calculate the primary/secondary current. Should I use Power/voltage or voltage/...

Question regarding 4.1k Three phase power. I guess I don't understand the solution very well. I posted my solution as well. I got the right answer because that was close to my calculation. Can someone explain the solution? I don't understand why he ignores the reactance of the line when...

I have a question regarding the current transformer. For question 1.1m I am unclear about how primary current changes affect the accuracy. Why accuracy is 2*0.3%?

I went through a few practice exams and encountered some relay questions. Normally questions gave you the relay number, and ask you the purpose of the relay. Do I need to remember all the relay numbers? how do I know what type of relay it is during the exam?

I found this induction motor question on youtube. Learned a lot, also have a question for(III) Magnetizing Reactance. Seem like Zack used total NL reactive power to calculate the magnetizing reactance. he calculated that total NL reactive power is 49513 VAR, then used 575 square / 49513 I...

problem: Calculate the minimum size of TW type copper conductors required to feed a 45KVA 3 phase continuous load from a 480V/277V 3 phase 4 wire power distribution board. The temperature rating of equipment terminals is 60 C( 140F) The solution uses 45K/(sqrt 3*480) to calculate the ampacity...

I have a question regarding this one in NEC. 430.24 Several Motors or a Motor(s) and Other Load(s). Conductors supplying several motors, or a motor(s) and other load(s), shall have an ampacity not less than the sum of each of the following: (1) 125 percent of the full-load current rating of the...

I am confused about the table Table 310.15(B)(2)(a) Ambient Temperature Correction Factors Based on 30°C (86°F) , and Table 310.15(B)(2)(b) Ambient Temperature Correction Factors Based on 40ºC (104ºF). Can someone explain to me.

Can anyone help me visualize the circuit? I got the data but did wrong on the calculation.

Can anyone tell me that in NEC book. table 210.24. what are the units for all the requirements? I am assuming

can anyone tell me that in table 220.12, what does the number with superscript "b" mean?

Can only one explain to me why the question does not need to convert to a single-phase for calculation? and why does question 11 need to convert to a single-phase?

what kind of fault can use the MVA method? can you use MVA method for three phase short?

Can anyone help me understand this. The question said that maximum power is 5000MW occurs at angle 90 degree. if the power angle is 90 degree, does it mean it's pure reactive power? if it's reactive power, why the maximum power is MW instead of MVAR? For solution, why we use 3* 8.165 square *...

Can anyone explain this? The answer shows B with reference 460.9 460.9 Rating or Setting of Motor Overload Device. Where a motor installation includes a capacitor connected on the load side of the motor overload device, the rating or setting of the motor overload device shall be based on the...

Can anyone suggest some methods on how to study the NEC book? Are there any practice questions specifically for the NEC book?