7.a. If a 575-volt three-phase motor originally connected in 3-parallel △ is reconnected in 5-parallel Y, the new voltage is A. 501 volts. B. 794 volts. c. 747 volts. 7.b. The total flux per pole of a reconnected motor is 900,000 lines of force. If the cross-sectional area of the laminated core is 6 sq in. and the cross-sectional area of the teeth per pole is 14 sq in., the flux density in the teeth is approximately A. 120,000 lines. B. 101,000 lines. C. 105,000 lines.

7.a. If a 575-volt three-phase motor originally connected in 3-parallel △ is reconnected in 5-parallel Y, the new voltage is A. 501 volts. B. 794 volts. c. 747 volts. 7.b. The total flux per pole of a reconnected motor is 900,000 lines of force. If the cross-sectional area of the laminated core is 6 sq in. and the cross-sectional area of the teeth per pole is 14 sq in., the flux density in the teeth is approximately A. 120,000 lines. B. 101,000 lines. C. 105,000 lines.

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 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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