A 2300-V, 1100 HP, 0.8-PF leading, 60-Hz, two-pole, Y-connected synchronous motor has a synchronous reactance of 2.5 N and an armature resistance of 0.3 Q. At 60 Hz, its friction and windage losses are 40 KW, and its core losses are 20 KW. This machine is operating at rated conditions, and its copper losses is estimated as 8 % of its input power. What is the efficiency of this motor? Select one: O a. None b. %n = 85.7 % c. %n = 92.65 % d. %n = 81.6 % e. %n = 77.28 %

A 2300-V, 1100 HP, 0.8-PF leading, 60-Hz, two-pole, Y-connected synchronous motor has a synchronous reactance of 2.5 N and an armature resistance of 0.3 Q. At 60 Hz, its friction and windage losses are 40 KW, and its core losses are 20 KW. This machine is operating at rated conditions, and its copper losses is estimated as 8 % of its input power. What is the efficiency of this motor? Select one: O a. None b. %n = 85.7 % c. %n = 92.65 % d. %n = 81.6 % e. %n = 77.28 %

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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