A 2300-V, 800 HP, 0.8-PF leading, 60-Hz, two-pole, Y-connected synchronous motor has a synchronous reactance of 2.5 Q and an armature resistance of 0.3 Q. At 60 Hz, its friction and windage losses are 40 KW, its core losses are 20 KW, and its stray losses are 2.5 KW This machine is operating at rated conditions, and its copper losses is estimated as 45 % of the total losses. What is the efficiency of this motor? Select one: a. %n = 74.28 % b. %n = 88.65 % c. %n = 84.0 % d. %n = 80.16 % e. None Clear my choice

A 2300-V, 800 HP, 0.8-PF leading, 60-Hz, two-pole, Y-connected synchronous motor has a synchronous reactance of 2.5 Q and an armature resistance of 0.3 Q. At 60 Hz, its friction and windage losses are 40 KW, its core losses are 20 KW, and its stray losses are 2.5 KW This machine is operating at rated conditions, and its copper losses is estimated as 45 % of the total losses. What is the efficiency of this motor? Select one: a. %n = 74.28 % b. %n = 88.65 % c. %n = 84.0 % d. %n = 80.16 % e. None Clear my choice

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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