Open Delta Method of Testing of Transformer
Q. Explain open delta method of testing of transformer.
The method of transforming 3-phase power by 3 windings i.e. 3 transformers is a regular ordinary method in which 3 units of 10 KVA will supply a power of 3 x 10=30 kVA. But it is possible to transforms 3 phase power by means of only two single phase transformers by opening delta connection (when one of the three transformers disabled) By T-connections also 3 phase can be transformed by only two single phase transformers phases A, B and C, a, b and supply R Y B phase transformers.
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