(a) Three identical coils, each of resistance 10 Q and inductance 42 mH are connected (i) in star and (ii) in delta to a 415 V, 50 Hz, 3-phase supply. Determine the phase current, the line current and the total power dissipated in each case. (c) Two wattmeters are connected to measure the input power to a balanced 3-phase load by the two-wattmeter method. If the instrument readings are 8 kW and 4 kW, determine (i) the total power input and (ii) the load power factor.

(a) Three identical coils, each of resistance 10 Q and inductance 42 mH are connected (i) in star and (ii) in delta to a 415 V, 50 Hz, 3-phase supply. Determine the phase current, the line current and the total power dissipated in each case. (c) Two wattmeters are connected to measure the input power to a balanced 3-phase load by the two-wattmeter method. If the instrument readings are 8 kW and 4 kW, determine (i) the total power input and (ii) the load power factor.

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

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.5P: A 60Hz, single-phase source with V=27730 volts is applied to a circuit element. (a) Determine the...

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Three-Phase Power Calculations