DC Network Theorems Unit 10 – Delta and Wye Networks
Conversion from delta to wye generates a wye circuit that is electrically identical to the delta
network. To determine each wye resistor, divide the product of the two adjacent delta resistors
by the sum of all the delta resistors.
PRODUCT OF 2 ADJACENT Rs IN DELTA
RY = —————————————————
SUM OF Rs IN DELTA
Conversion from wye to delta generates a delta circuit that is electrically identical to the wye
network. To determine each delta resistor, divide the sum of all cross products in the wye
network by the opposite resistor in the wye network.
SUM OF ALL CROSS PRODUCTS IN Y
RD = ——————————————————————
OPPOSITE R IN Y
Delta to wye transformation simplifies bridge circuit calculations. To easily determine total
circuit current (IT), convert one bridge delta section to a wye. This conversion results in a
series/parallel circuit in which total current equals the supply voltage divided by the total circuit
resistance (IT = VS/RT).