<P> In a symmetrical three - phase four - wire, wye system, the three phase conductors have the same voltage to the system neutral . The voltage between line conductors is √ 3 times the phase conductor to neutral voltage: </P> <Dl> <Dd> V LL = 3 V LN . (\ displaystyle V_ (\ text (LL)) = (\ sqrt (3)) V_ (\ text (LN)).) </Dd> </Dl> <Dd> V LL = 3 V LN . (\ displaystyle V_ (\ text (LL)) = (\ sqrt (3)) V_ (\ text (LN)).) </Dd> <P> The currents returning from the customers' premises to the supply transformer all share the neutral wire . If the loads are evenly distributed on all three phases, the sum of the returning currents in the neutral wire is approximately zero . Any unbalanced phase loading on the secondary side of the transformer will use the transformer capacity inefficiently . </P>

What is the difference between 3 phase delta and 3 phase wye