Watlow Ltd- Reference Equations - Delta and Wye Circuit Equations

Delta and Wye Circuit Equations
Typical 3-Phase Wiring Diagrams and Equations for Resistive Heaters (click on images to inlarge)

Definitions
For Both Wye and Delta (Balanced Loads)	Wye and Delta Equivalent
V_P = Phase Voltage V_L = Line Voltage I_P = Phase Current I_L = Line Current R = R1 = R2 = R3 = Resistance of each branch W = Wattage	W_DELTA = 3 W_WYE W_ODELTA = ¾ W_DELTA W_OWYE = ½ W_WYE
Equations
3-Phase Wye(Balanced Load)	3-Phase Open Wye(No Neutral)
I_P = I _L V_P = V_L/1.73 W_WYE = V_L²/R = 3 (V_P²)/R W_WYE = 1.73V_LI_L	I_PO = I _LO V_PO = V_L/2 W_OWYE = ¹/₂ ( V_L /R) W_OWYE = 2 (V_PO²/R)
3-Phase Delta (Balanced Load)	3-Phase Open Delta
I_P = I _L/1.73 V_P = V_L W_DELTA = 3(V_L²)/R W_DELTA = 1.73V_LI_L	V_P = V_L I_PO1 = I _PO3 = I _LO2 I_LO3 = 1.73 I _PO1 W_ODELTA = 2(V_L²/R)

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