Delta and Wye Circuit Equations Notes

Delta and Wye Circuit Equations 
Typical 3-Phase Wiring Diagrams and Equations for Resistive Heaters 
Definitions

ForBoth Wye and Delta (Balanced Loads) VP = Phase Voltage VL = Line Voltage IP = Phase Current IL = Line Current R = R1 = R2 = R3 = Resistance of each branch W = Wattage

Wyeand Delta Equivalent WDELTA = 3 WWYE Open3-Phase Circuit Formulas: Open Delta Watts = 2/3 WDELTA Open Wye Watts = 1/2 WWYE Open 4-wire Wye Watts = 2/3 WWYE

3-Phase Wye (Balanced Load)		3-Phase Open Wye (No Neutral)
IP = I L VP = VL/1.73 WWYE = VL2 /R = 3 (VP2) /R WWYE = 1.73VLIL		IPO = I LO VPO = VL/2 WOWYE = 1/2 ( VL /R) WOWYE = 2 (VPO2/R) WOWYE = VLILO
3-Phase Delta (Balanced Load)		3-Phase Open Delta
IP = I L/1.73 VP = VL WDELTA = 3(VL2)/R WDELTA = 1.73VLIL		VP = VL IPO1 = I PO3 = I LO2 ILO3 = 1.73 I PO1 WODELTA = 2(VL2/R )