1-A l-ph transformer, 50HZ, core type transformer has square core of density is 1 Wb/m². If the iron factor is 0.95, the approximately induced voltage per turm is - --. a) 6 b) 11 12 d) none of the above. 2-A transformer has full-load iron loss of 500 W. the iron loss at half-load will be a) 125 W b) 250 WS00 W d) none of the above. 3-A transformer will have maximum efficiency at ---------. a) full-load b) no-load c) 90% load d)none of the above 4- The hysteresis loss in a certain transformer is 40W and the eddy current loss is 50 W (both at 30HZ), then the iron loss at 50 Hz is The flux density being the same. a) 180W (b 204W c) 302 none of the previous. 5- The voltage per tum of the high voltage winding of a transformer is per turn of the low voltage winding. a) More than b) the same as c) less than d) none of the previous - the voltage

1-A l-ph transformer, 50HZ, core type transformer has square core of density is 1 Wb/m². If the iron factor is 0.95, the approximately induced voltage per turm is - --. a) 6 b) 11 12 d) none of the above. 2-A transformer has full-load iron loss of 500 W. the iron loss at half-load will be a) 125 W b) 250 WS00 W d) none of the above. 3-A transformer will have maximum efficiency at ---------. a) full-load b) no-load c) 90% load d)none of the above 4- The hysteresis loss in a certain transformer is 40W and the eddy current loss is 50 W (both at 30HZ), then the iron loss at 50 Hz is The flux density being the same. a) 180W (b 204W c) 302 none of the previous. 5- The voltage per tum of the high voltage winding of a transformer is per turn of the low voltage winding. a) More than b) the same as c) less than d) none of the previous - the voltage

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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