 # 3 Phase Power - Delta and Wye Circuit Equations

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

 For Both 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 Wye and Delta Equivalent WDELTA = 3 WWYE Open 3-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 LVP = VL/1.73WWYE = VL2 /R = 3 (VP2) /RWWYE = 1.73VLIL IPO = I LOVPO = VL/2WOWYE = 1/2 ( VL /R)WOWYE = 2 (VPO2/R)WOWYE = VLILO 3-Phase Delta(Balanced Load) 3-Phase Open Delta IP = I L/1.73VP = VLWDELTA = 3(VL2)/RWDELTA = 1.73VLIL VP = VLIPO1 = I PO3 = I LO2ILO3 = 1.73 I PO1WODELTA = 2(VL2/R )

## Next Steps

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