An alternator stator winding protected by a percentage differential relay is shown in Fig. 1.12.8 (a). The relay has 0.15 amp minimum pick up and a 12 % slope of characteristics (i, - iz) V. (¹1+¹2). A high resistance ground fault has occured near the grounded neutral end of the generator winding while generator is carrying load. The currents flowing at each end of the generator winding are shown in Fig. 1.12.8(a). Assuming that the CT's have 400/5 amps ratio and no inaccuracies will the relay trip the gene tor CB under this fault condition.

An alternator stator winding protected by a percentage differential relay is shown in Fig. 1.12.8 (a). The relay has 0.15 amp minimum pick up and a 12 % slope of characteristics (i, - iz) V. (¹1+¹2). A high resistance ground fault has occured near the grounded neutral end of the generator winding while generator is carrying load. The currents flowing at each end of the generator winding are shown in Fig. 1.12.8(a). Assuming that the CT's have 400/5 amps ratio and no inaccuracies will the relay trip the gene tor CB under this fault condition.

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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