Electrical Machines Questions and Answers_pag371

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Explanation: For conducting short circuit test, l.v. winding is short circuited and it is not 
performed at rated voltage. 
13. Transformers with high leakage impedance is used in 
a) arc welding 
b) power distribution 
c) power generating terminals 
d) none of the mentioned 
View Answer 
Answer: a 
Explanation: The feature of the high impedance is extracted in the arc welding applications. 
14. Which of the following conditions have to ensured for a open-circuit test? 
A. Performed on L.V side 
B. Leakage impedance can be obtained 
C. It is performed at rated voltage 
D. It gives magnetizing impedance 
a) B,D 
b) A,B,C 
c) B,C,D 
d) A,C,D 
View Answer 
Answer: d 
Explanation: Leakage impedance is not found from open-circuit test. 
15. Which of the following conditions have to ensured for a open-circuit test? 
A. Performed on L.V side 
B. Leakage impedance can be obtained 
C. It is performed at 10-12% of rated voltage 
D. It gives magnetizing impedance 
a) B,D 
b) A,B,C 
c) B,C,D 
d) A,D 
View Answer 
Answer: a 
Explanation: Leakage impedance is not found from open-circuit test. And it is performed on the 
rated voltage to account for core losses. 
16. Which of the following informations are not obtained from short-circuit test? 
I. Ohmic losses at rated current 
II. Equivalent resistance and leakage reactance 
III. Core losses 
IV. Voltage regulation 
a) I,II 
b) II,III 
c) I,II,IV