Example 32.81. A 5-kVA distribution transformer has a full-load efficiency at unity p.f. of 95 %, the copper and iron losses then being equal. Calculate its all-day efficiency if it is loaded throughout the 24 hours as follows: No load for Quarter load for Full load for 10 hours 7 hours 2 hours Half load for Assume load p.f. of unity. 5 hours (Power Apparatus-I, Delhi Univ. 1987)

Example 32.81. A 5-kVA distribution transformer has a full-load efficiency at unity p.f. of 95 %, the copper and iron losses then being equal. Calculate its all-day efficiency if it is loaded throughout the 24 hours as follows: No load for Quarter load for Full load for 10 hours 7 hours 2 hours Half load for Assume load p.f. of unity. 5 hours (Power Apparatus-I, Delhi Univ. 1987)

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

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