Wyte to Delta Conversion

Y to  Conversions
In terms of power, currents & line voltages, the following sources are the same and may be used interchangably in most cases. Note, the Y connection should be used in a one-line diagram.  Wye connected source           
Figure 8: A Y Source
VA = Vab / (√3 <30°)
to
Delta connected source
Figure 9: A Delta Source
Vab = VA √3(<30°)

Similarly, the two loads given below are the same in terms of the resulting power, line currents and line voltages and can usually be substituted as desired. Note that the Y connection is the one needed for the one-line diagram!

Wye connected load

Figure 10: A Y Impedance Load to

Delta connected load

Figure 11: A  Impedance Load