Two tests were performed on a 40-kVA transformer to predetermine its efficiency. The results were: Open circuit : 250 V at 500 W Short circuit : 40 V at F.L. current, 750 W both tests from primary side. Calculate the efficiency at rated kVA and 1/2 rated kVA at (i) unity p.f. (ii) 0.8 p.f. [96.97% ; 96.68% ; 96.24% ; 95.87%]

Two tests were performed on a 40-kVA transformer to predetermine its efficiency. The results were: Open circuit : 250 V at 500 W Short circuit : 40 V at F.L. current, 750 W both tests from primary side. Calculate the efficiency at rated kVA and 1/2 rated kVA at (i) unity p.f. (ii) 0.8 p.f. [96.97% ; 96.68% ; 96.24% ; 95.87%]

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 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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