3 SINGLE PHASE TRANSFORMER CONNECTED INTO A STAR DELTA 3∅ GROUP
They are joined by means of common yokes, the top yoke 2, and the bottom yoke 3. The phase windings are arranged on the limbs and are connected into three phase circuit to make a 3∅ transformer.
The first part of the transformer is a 3∅(phase) star connected transformer. While the second part of the transformer is a 3∅(phase) delta connected transformer. Symbolised as ∆
The 3-∅ transformer is obtained by connecting the terminals of three single-phase transformer in such a way as to form a three-phase circuits.
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