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In a balanced three phase wye-delta system the source has an abc phase sequence and Van = 120 angle 40 Vrms. The line and load impedance's are 0.4+j0.4 and 24+j18 respectively. Find the Delta currents in the load? Link to the video: https://www.youtube.com/results?search_query=Irwin+11.27 So I...

On complex imaginaries video on sqrt of 3. They solver for power with a delta source and a single phase load. Valies given Iphase = 25 A and V line to line = 480 V what is the Power? So I though of 2 ways to do this 1 is to convert phase current to line current and multiply. The seconf is to...

Why is the per unit impedance for Zt2=j1 not put in parallel with 0.2+j0.546? There really is no explanation to problem other than picture or I would put it down also.

I know this has been asked time and time again on here but I dont think my question has been answered in other threads. So here it goes why is the formula for finding S of the transmission line S=V^2/Z instead of S=sqrt (3)(V^2/Z)? 

How did they get the impedance from NEC Table 9 I get .36+j.135 why did they use kcmil values?

So I know it is to be used in phasor calculations, and not in magnitude. However, it seems to me that sometimes they elect to use and sometimes not. For example in NCEES Problem 129 they don't use it when converting from 480 Volts, but in NCEES Problem 111 they do. Why is this?

Find the Voltage regulation of a 25 kilovolt ampere, 480 V, 3 phase wye connected synchronous generator with the power factor of a) 0.81 lagging and b) 0.81 leading at rated voltage full load the winding resistance is 0.15 Ω per face, and the synchronous reactance is 6.1 Ω per face. Why did...

For the 3 phasy wye transformer what is Ia? Given on diagram VAB = VBC = VCA= 480 V, Load KVA = 25 KVA and pf = 0.75 lagging. I solved this this way: S/3 = 8.33 KVA angle -41.4 VAB/sqrt (3) = 480/sqrt (3) = 277 angle -30  IA = 8333/277 = 30.08 angle -11 and even if I do this using line to...

A 480Y/277, 80 kW noncontinuous load with a 0.8 pf consists of less than 50% ballast-type lighting. The feeder length is 110m. Applying the 3% fine print note No. 2 recommendation from Sec. 215.2(A)(3), what is the maximum recommended voltage drop for every 1000 Ampere-Foot?  Here is what...

I am confused why they divide 65 kV by the sqrt of 3 and the MVA by 3. I get that they are converting to a single phase approach to solving the problem and I get the answer but the problem never states whether the line is in a delta or wye configuration. Would this not make a difference? So how...

A 3-phase, 4-wire, neutral-grounded, wye-connected utility line has a phase to phase voltage of 13.2 kv. A complex load of (200+j100) kVA is connected between phase A and neutral. An identical load is connected between Phase B and neutral. The neutral current is most nearly: (a) 0 (b) 9.8 (c)...