Ques. Is the above method usually employed?
Ans. No, the method shown in fig. 1,997 is generally used.
Three Phase Connections.—There is not so much freedom in making three phase transformer connections, as with single or two phase, because the three phases are inseparably interlinked. However, the system gives rise to several methods of transformer connection, which are known as:
- 1. Star;
- 2. Delta;
- 3. Star-delta;
- 4. Delta-star.
Figs. 1,992 to 1,995.—Three phase transformer connections. Fig. 1,992 delta connection; fig. 1,993 star connection; fig. 1,994 delta star connection; fig. 1,995 star-delta connection.
Delta Connection.—In the delta connection both primaries and secondaries are connected in delta grouping, as in fig. 1,992.
Star Connection.—This method consists in connecting both the primaries and secondaries in star grouping, as in fig. 1,993.