i) Draw the connection diagram:-
ii) List any two advantages of Delta-Star connection:
1. As primary is connected in delta, distortion due to third harmonic is absent 2. Phase shift of 30 degree elec. is present between the primary and secondary line voltages and line currents 3. Small cross section wire can be used on primary side due to delta connection. 4. Due to availability of neutral on the secondary side, it is possible to use it for three phase four wire system.
iii) State its area of application
1. It is used for step up the voltages at the sending end of high tension transmission lines. 2. Used as distribution transformer 3. Due to star type secondary used for small as well as large loads. 4. As the neutral is available on secondary side it is used for three phase four wire system that is applicable for both single phase as well as three phase load.