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Physicist3

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Also, when converting from delta to star, do you make the initial delta voltages to be at 30°, so that when you divide by sqrt(3) and subtract 30° to get the equivalent star phase voltage this will be at 0 degrees?, or do you take the voltages in the initial delta source to be at 0°?

E.g., should the conversion be undertaken as below if the delta voltages are 415V, as there are several ways of doing this, depending on what is taken as the reference (0° angle) (Vp = Phase Voltage and Vl = Line Voltage)

If Delta VL = 415V@30° → Star Vp = 415/√3 @ 0° & Star VL = 415V@30°

Or

Delta VL = 415V@0° → Star Vp = 415/√3 @ -30 & Star VL = 415V@ 0°

or

Delta VL = 415V@0° → Star Vp = 415V@0° & Star VL = √3 * 415V @ 30°

I'm really sorry if this has confused anyone but I would appreciate some help as this should be so simple and is really bugging me. I'm not sure whether I'm making a mountain out of a molehill here or whether I have missed something really obvious, its the fact that our lecturer said it doesn't matter what is taken as reference, although surely this would knock everything out by 30° if true?

Thanks