The zigzag connection is a three-phase connection and is constructed as shown in Figure below. There are three pairs of windings, each having a 1:1 turns ratio. The left-hand set of windings shown in the figure is a conventional Y connection, a?-b?-c?, with the neutral N brought out. The open ends of the Y are electrically connected to the right-hand set of windings as follows: a?connects to the right-hand winding paired with to the b?-N winding, b?connects to the right-hand winding paired to c?-N winding, and c?connects to the right-hand winding paired to the a?-N winding. The opposite ends of the right-hand windings are brought out as the phase terminals a, b, and c. 
If three currents, equal in magnitude and phase, are applied to the three terminals, the ampere-turns of the a?-N winding cancel the ampere-turns of the c?- c winding, the ampere-turns of the b?-N winding cancel the ampere turns of the a?-a winding, and the ampere-turns of the c?-N winding cancel the ampere turns of the b?-b winding. Therefore, the transformer allows the three in-phase currents to easily flow to neutral. If three currents, equal in magnitude but 120