A single phase transformer is designed to operate from 50 Hz, 1100 V supply and to have an output voltage of 240 V at no load. The core has mean area of 30 cm2 and the flux density has not to exceed 1.3T. The number of secondary turns will be (a) 1270 (b) 1017 (c) 768 (d) 277  

1 Answer

Answer :

E2=e2=4.44*flux*N2*f=240 V


Flux=Flux density* Area



Area=30 cm =30*10-4 m2


Flux= 1.3*30*10-4  Wb=39*10-4 Wb


E=240= 4.44*39*10-4 *N2*50


     N2=277.

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