A 1000 V/400 V power transformer has a nominal short-circuit voltage Vsc = 40%....

 A 1000 V/400 V power transformer has a nominal short-circuit voltage Vsc = 40%. Which one of the following statements is correct ? 

(a) A voltage of 400 V appears across the short-circuited secondary terminals. 

(b) A voltage of 16 V appears across the short-circuited secondary terminals. 

(c) When the secondary terminals are short-circuited, the rated current flows at the primary side at a primary voltage of 400 V. 

(d) The primary voltage drops to 400 V, when the secondary terminals are short-circuited.
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1 Answer

Answer :

 A 1000 V/400 V power transformer has a nominal short-circuit voltage Vsc = 40%. Which one of the following statements is correct ? 

(a) A voltage of 400 V appears across the short-circuited secondary terminals. 

(b) A voltage of 16 V appears across the short-circuited secondary terminals. 

(c) When the secondary terminals are short-circuited, the rated current flows at the primary side at a primary voltage of 400 V. 

(d) The primary voltage drops to 400 V, when the secondary terminals are short-circuited.

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