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Y and Delta Network Transformation

Y Delta Formula

Y Impedance, R1 (Ohms) =
Y Impedance, R2 (Ohms) =
Y Impedance, R3 (Ohms) =
Transform Y to Delta:  

Y Network

Delta Impedance, Ra (Ohms) =
Delta Impedance, Rb (Ohms) =
Delta Impedance, Rc (Ohms) =
Transform Delta to Y:  

Delta Network

Add Series/ Parallel Resistor: