A balanced three phase AC circuit systems is energized by three equal alternating emf's of the same frequency but 120 degree apart. The phase impedance are equal. Also the currents are equal and 120 degree apart.

This type of connection is reffered to as 3 phase, 3 wire system. In this connection , the dissimilar ends of the 3 phase windings of a 3 phase ac generator are joined together, for example the starting ends of one phase is joined to finishing end of the other phase so on. In other words the three winding's are joined in series to form a closed mesh. three leads are taken out from the juntions to serve as the generator terminals.

The three phase voltages of this circuit always sum to zero

As seen from the diaram, there is only one phase winding completely included between any pair of terminals. Hence, in delta connection, the voltage between any pair of lines is equal of the phase voltage of the phase winding connected between the two lines considered.

Three AC emf's differing in time phase by 120 degree |

**DELTA (MESH) CONNECTED SYSTEM**This type of connection is reffered to as 3 phase, 3 wire system. In this connection , the dissimilar ends of the 3 phase windings of a 3 phase ac generator are joined together, for example the starting ends of one phase is joined to finishing end of the other phase so on. In other words the three winding's are joined in series to form a closed mesh. three leads are taken out from the juntions to serve as the generator terminals.

Delta connected System |

Relationships:

*VØ = VL : IØ = I**L/*√*(3)*
Where:

*VØ - phase voltage*

*IØ - phase current*

*VL - line voltage*

*IL - line voltage*

*Va + Vb + Vc =0*As seen from the diaram, there is only one phase winding completely included between any pair of terminals. Hence, in delta connection, the voltage between any pair of lines is equal of the phase voltage of the phase winding connected between the two lines considered.