1.) A 7.5 hp, 120 V series Da engine has an enduvi resistance of 0.2 ohms and a series excitation resistance of 0.16 ohms. Input current at full load is 58A. Rated speed is 1050 rpm. The magnetization curve is given in Fig.1. Core losses are 200Wv, mechanical losses average 240W. In this rinse; a) What is the efficiency of the engine at full load? b) what is the speed and efficiency of the engine if it operates with a 40A enduvi current?

1.) A 7.5 hp, 120 V series Da engine has an enduvi resistance of 0.2 ohms and a series excitation resistance of 0.16 ohms. Input current at full load is 58A. Rated speed is 1050 rpm. The magnetization curve is given in Fig.1. Core losses are 200Wv, mechanical losses average 240W. In this rinse; a) What is the efficiency of the engine at full load? b) what is the speed and efficiency of the engine if it operates with a 40A enduvi current?

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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Subject Electrical Machines 2
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