2.2 An ideal transformer has a turns ratio of 1:5 and is supplied at 200 V when the primary current is 3 A. Which of the following statements is false? [a] The turns ratio indicates a step-up transformer. [b] The secondary voltage is 40 V. [c] The secondary current is 0.6 A. [d] The transformer rating is 0.6 kVA. [e] The secondary voltage is 1 kV.

2.2 An ideal transformer has a turns ratio of 1:5 and is supplied at 200 V when the primary current is 3 A. Which of the following statements is false? [a] The turns ratio indicates a step-up transformer. [b] The secondary voltage is 40 V. [c] The secondary current is 0.6 A. [d] The transformer rating is 0.6 kVA. [e] The secondary voltage is 1 kV.

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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A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
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