Problem Solving 11: A 60 kva 4800/460 volt, 60 cycle, distribution transformer hasthe following resistance and leakage reactance values; Rp=0.70 ohm; Xp=2.8 ohmohm; Rs 0.0085 ohm; Xs=0.0275 ohm.(a). Calculate the equivalent resistance and reactance voltage drops for asecondary load current of 130.435 A in secondary terms and primary terms(b). Determine its equivalent resistance, impedance and reactanceIf it has the following result from its test:E_sc=60 volts,1_sc=12.5 amp;P_sc=1,000 wattsP_Oc=650 wattsin which two third is hysteresis loss.(c.) Determine the core loss when the transformer is connected to a 4700 (primary)volt 60 cycle source and 4400 (primary) volt 50 cycle source.(d.) Calculate the efficiencies of the transformer for a power factor of 0.8 for 1/2and 1 1/4 fractions of rated kilovolt ampere.(e.) Calculate the apparent power at which the transformer is at its maximumefficiency.Please answer letter c, d and e. Thank you!

Given: A 60 kVA 4800/460 volt, 60 cycles, distribution transformer has the following resistance and…

(c.) Determine the core loss when the transformer is connected to a 4700 (primary) volt 60 cycle source and 4400 (primary) volt 50 cycle source. (d.) Calculate the efficiencies of the transformer for a power factor of 0.8 for 1/2 and 1 1/4 fractions of rated kilovolt ampere. (e.) Calculate the apparent power at which the transformer is at its maximum efficiency.

(c.) Determine the core loss when the transformer is connected to a 4700 (primary) volt 60 cycle source and 4400 (primary) volt 50 cycle source. (d.) Calculate the efficiencies of the transformer for a power factor of 0.8 for 1/2 and 1 1/4 fractions of rated kilovolt ampere. (e.) Calculate the apparent power at which the transformer is at its maximum efficiency.

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

Chapter14: Power Distribution

Section: Chapter Questions

Problem 14.8P

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