Delta-Wye Conversions

These equations are used to transform a delta-connected set of resistances to a wye-connected (Y-connected) set of resistances.

            Delta transformer winding drawing<===>Wye Y transformer winding drawing


Δ - Y  Conversion
R1 =
Rb·Rc
Ra + Rb + Rc
R2 =
Ra·Rc
Ra + Rb + Rc
R3 =
Ra·Rb
Ra + Rb + Rc

Y - Δ  Conversion
Ra =
R1·R2 + R2·R3 + R3·R1
R1
Rb =
R1·R2 + R2·R3 + R3·R1
R2
Rc =
R1·R2 + R2·R3 + R3·R1
R3