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Question: "A three-phase transformer bank is to handle 500 kVA and have a 34.5/11-kV voltage ratio. Find the rating of each individual transformer in the bank (high voltage, low voltage, turns ratio, and apparent power) if the transformer bank is connected to open wye—open delta." My ans: HV...

Found somewhere in the board, may be useful for discussion. "If a motor with 60A needs a feeder ckt of 1.25*60=72A  and a capacitor rated for 60A is connected somewhere near motor terminals ( A hypothetical case for understanding purpose only), will the motor feeder ckt conductors now required...

Question states "Which breaker(s) would be most likely to provide back up protection for breaker #4?". Ans in the book is option b. 2, 7 & 6 I understand the other options in the book were not valid so the correct will be option b. But lets say we don't have any options then i think the...

Graffeo Ex 53: In this example, for Double line to ground fault current only Ib is considered here which is incorrect. I think the fault current shall be "Ib+Ic" or "3 x Ia0" which will lead to the answer "j10.71". Please correct me if i am wrong.

Question states : "A 3-phase, 22 kV, 500 MVA star-connected synchronous generator has a reactance Xs of 1.5 pu and supplies 0.8 pu real power (P) at the rated voltage, with a lagging power factor of 0.6 to the load.Calculate the magnitude of the actual complex power consumed by the load in MVA."...

Cut sheets are taken form old thread (link at the end) Question) Ans: (only initial description, no calculation) Any idea how PU impedance of generator is 0.1 pu? I couldn't understand how identical X/R ratios leads to ratio of powers that provides PU impedance of GEN. Please go through the...

If there's a fault at point D and breaker 5 fails to trip, which breakers should trip next? (Ans: says 1 & 3 would trip if 5 failed to trip.) Can somebody explain this to me? Source: 

12. Can someone please explain the answer to me. Ans:

Looking for Power PE Materials cheap here in Japan. like: - Complex Imaginary - Camera PPI Practice Exam / problems Is there way to buy softcopies of these?

If i change the P (hp) to P (watt) and use the formula P=sq.rt(3) x VI, the value of current will be 93.6 A. This is different from the answer in the example as, I=600Ph / E. Am i missing something here. Cuz in exam for these kind of question, the first thing i will remember is P=sq.rt(3) x...

Can someone please help how Pmax derived here?

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