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Actually you don't want the Patent too soon. What you want is a Patent-Pending, because once granted the patent it is made public! Phil

Abdolazim Hasseli... first get a reliable Patent Attorney! <b>Do Not</b>, repeat, <b>Do Not</b>, use those that advertise on TV!!! Regards, Phil Corso

Shakarami... the reason I suggested that you first derive wave-shape is because there are simple answers if the shape is triangular, trapezoidal, clipped sine-wave, etc! Phil

Shakarami... to determine the RMS value of any signal you must extract its wave-shape for one period. If you need additional instruction let us know! Regards, Phil Corso

Only if if the single is sinusoidal! Phil

jmcquarrie... there is someting unusual about your observations or I have misinterpreted your problem:: 1) Why would a 3-ph,480V motor, need a "cap-Start?" 2) Do you have a fused-disconnect-switch? Or are the two elements, the switch and the fuse-blocks, in different enclosures? 3) And...

AT... would you prefer the RoT formula, ignoring impact of X/R ratio and exciting-current, on List? Phil

Gray Wolf... What has AB said? Regards, Phil

AT... Additional to my previous post: 5) " %X = . . . . . = 10.9503 " (NO!) Your calculated %X value is greater than the given %Z value! Phil

AT... Several comments about your thesis: 1) "When I did the calculation => I(L)=800kVA / [ SQRT(3)- 480]= 962.250A!" You are correct, I erred! 2) "% Z ... shorting sec'y, decreasing pri'y V until rated-current flows in pri'y or sec'y" Pri'y (NO! Sec'y (YES!) 3) "Do you think my 2nd...

AT... OK! Let’s start with basics: A) Given: kVA(L) = 800; PF(L) = 0.8; kV(L) =0.48; Xfmr’s % Z = 5.75 ! B) Find: Load Current Magnitude: I(L) = kVA(L) / [ SQRT(3) * kV(L) ] = 1,155A ! C) Find: Load Current in Complex Units; Ir(L): I(L) * PF(L) + j * I(L)*SQRT[1-PF(L)²] ! D)...

AT... I hope you don't mind my asking the following just to be sure about your query: 1) A Xfmr's Nameplate never lists Load- Characteristics! 2) Thus, are you looking for the mathematical procedure to determine what the Voltage-Regulation (VR) is, for the Load you defined as 800kVA at...

Shaheed... further to my post on grounding. Ground-Fault level has little to do with 3-phase Momentary or Interrupting fault-duty. Max-current allowable is selected to minimize iron-damage to major Electrical Apparatus, such as Xfmrs, Alternator, and Large Motors! Phil

Shaheed... Expert's calc'n shows the Grid contribution as 14.4kA! Which of the Swgr cubicles shown on the SLD is used for the 20MVA Xfmr's incomer VCB? Phil

Shaheed... correction to earlier post: The busbar, its joints, insulators, and bus-stubs, must withstand mechanical forces proportional to Isc^2, which will be about 9 times greater for Expert's 25kA value than for your 8.33kA value! Phil

Shaheed... regarding you ground-fault concerns; what are the parameters of the selected NGT or NGT system? Phil

Shaheed... your size-calc of the GTG's VCB Isc is based on your presumption that the Gen's contribution to a fault anywhere will not exceed 8.33kA. Expert's size-calc, ~25kA, is based on contribution from all sources, and he is right! Consider as a fault location, the Gen's VCB cubicle...

Shaheed... one question; What is Rated Short-Circuit Interrupting and Closing-Duty of the existing Metal-Clad Switchgear Line-up? Regards, Phil

Lespoils... if there is the possibility you can get secondary and tertiary loads about equal, then there is a trick you can use! Regards, Phil ([email protected])

Lespoils... stop hitting you head against a brick wall! You said it yourself... "Maybe I'm wrong"! It can't be done! You end up with 3 equations having 2 unknowns. Is the 3-winding Xfmr being considered because the 2-winding solution results in Short-Circuit Duty that is too high...