2. A 750-kVA, 3-phase, 60HZ transformer has a voltage ratio (line voltages) of 33/11kV and is delta-wyeconnected. The resistances per phase are: primary side 270, secondary side 0.587N and iron loss is2589W. Calculate the efficiency at full-load and 3/4 of full load respectively (a) at unity p.f. and (b) 0.866p.f.3. A load of 265KVA is to be supplied by two parallel transformers connected on both their primary andsecondary sides. Technical data of the transformers are as follows: Transf No.1: 150KVA, 13800/240V,%R= 0.89%, %X=4.3% Transf No.2: 225KVA, 13800/240V, %R= 1.12%, %X=4.87. Determine the kVA andcurrents supplied by each if pf of load is 0.866 lagging.

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2. A 750-kVA, 3-phase, 60HZ transformer has a voltage ratio (line voltages) of 33/11kV and is delta-wye connected. The resistances per phase are: primary side 272, secondary side 0.587N and iron loss is 2589W. Calculate the efficiency at full-load and 3/4 of full load respectively (a) at unity p.f. and (b) 0.866 p.f.

2. A 750-kVA, 3-phase, 60HZ transformer has a voltage ratio (line voltages) of 33/11kV and is delta-wye connected. The resistances per phase are: primary side 272, secondary side 0.587N and iron loss is 2589W. Calculate the efficiency at full-load and 3/4 of full load respectively (a) at unity p.f. and (b) 0.866 p.f.

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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