What will happen if the transformers working in parallel are not connected with regard to polarity ?
Correct answer: B. Incorrect polarity will result in dead short circuit
- A. The power factor of the two trans-formers will be different from the power factor of common load
- B. Incorrect polarity will result in dead short circuit
- C. The transformers will not share load in proportion to their kVA ratings
- D. none of the above
Explanation
Connecting parallel transformers with opposite polarity places their induced voltages in opposition, producing a very large circulating current and effectively a short circuit. Correct polarity is therefore essential before closing the parallel connection.
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