Fundamentals of Electric Circuits
6th Edition
ISBN: 9780078028229
Author: Charles K Alexander, Matthew Sadiku
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 12, Problem 31P
A balanced delta-connected load is supplied by a 60-Hz three-phase source with a line voltage of 480 V. Each load phase draws 24 kW at a lagging power factor of 0.8. Find:
- (a) the load impedance per phase
- (b) the line current
- (c) the value of capacitance needed to be connected in parallel with each load phase to minimize the current from the source
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Clear and correct or dislike
low voltage systems
In the reverse phase, a 1000 kw powerful load under 0.5 power factor is fed from a 5 kv source.A capacitor is connected in parallel with the load to increase the power factor to 0.8.
a-) Find the required capacitor power.
b-) Compare the apparent power before and after compensation.
Power factor correction is a method to do which of the following.
Chapter 12 Solutions
Fundamentals of Electric Circuits
Ch. 12.2 - Given that Vbn=22030V, find Van and Vcn, assuming...Ch. 12.3 - A Y-connected balanced three-phase generator with...Ch. 12.4 - One line voltage of a balanced Y-connected source...Ch. 12.5 - A positive-sequence, balanced -connected source...Ch. 12.6 - In a balanced -Y circuit, Vab=44015 and ZY = (12 +...Ch. 12.7 - For the Y-Y circuit in Practice Prob. 12.2,...Ch. 12.7 - Calculate the line current required for a 30-kW...Ch. 12.7 - Assume that the two balanced loads in Fig....Ch. 12.8 - The unbalanced -load of Fig. 12.24 is supplied by...Ch. 12.8 - Find the line currents in the unbalanced...
Ch. 12.9 - Prob. 11PPCh. 12.9 - For the unbalanced circuit in Fig. 12.32, use...Ch. 12.10 - Repeat Example 12.13 for the network in Fig. 12.24...Ch. 12.10 - Let the line voltage VL = 208 V and the wattmeter...Ch. 12.10 - If the load in Fig. 12.35 is delta-connected with...Ch. 12 - What is the phase sequence of a three-phase motor...Ch. 12 - If in an acb phase sequence, , then Vcn is:Ch. 12 - Which of these is not a required condition for a...Ch. 12 - Prob. 4RQCh. 12 - Prob. 5RQCh. 12 - In a Y-Y system, a line voltage of 220 V produces...Ch. 12 - In a - system, a phase voltage of 100 V produces a...Ch. 12 - When a Y-connected load is supplied by voltages in...Ch. 12 - Prob. 9RQCh. 12 - Prob. 10RQCh. 12 - If Vab = 400 V in a balanced Y-connected...Ch. 12 - What is the phase sequence of a balanced...Ch. 12 - Given a balanced Y-connected three-phase generator...Ch. 12 - A three-phase system with abc sequence and VL =...Ch. 12 - For a Y-connected load, the time-domain...Ch. 12 - Using Fig. 12.41, design a problem to help other...Ch. 12 - Obtain the line currents in the three-phase...Ch. 12 - In a balanced three-phase Y-Y system, the source...Ch. 12 - A balanced Y-Y four-wire system has phase voltages...Ch. 12 - For the circuit in Fig. 12.43, determine the...Ch. 12 - In the Y- system shown in Fig. 12.44, the source...Ch. 12 - Using Fig. 12.45, design a problem to help other...Ch. 12 - In the balanced three-phase Y- system in Fig....Ch. 12 - Obtain the line currents in the three-phase...Ch. 12 - The circuit in Fig. 12.48 is excited by a balanced...Ch. 12 - A balanced delta-connected load has a phase...Ch. 12 - A positive sequence wye-connected source where ,...Ch. 12 - If Van = 22060 V in the network of Fig. 12.49,...Ch. 12 - For the - circuit of Fig. 12.50, calculate the...Ch. 12 - Prob. 20PCh. 12 - Three 440-V generators form a delta-connected...Ch. 12 - Find the line currents IaA, IbB, and IcC in the...Ch. 12 - A balanced delta connected source is connected to...Ch. 12 - A balanced delta-connected source has phase...Ch. 12 - In the circuit of Fig. 12.54, if , , , find the...Ch. 12 - Using Fig. 12.55, design a problem to help other...Ch. 12 - A -connected source supplies power to a...Ch. 12 - The line-to-line voltages in a Y-load have a...Ch. 12 - A balanced three-phase Y- system has V rms and Z =...Ch. 12 - In Fig. 12.56, the rms value of the line voltage...Ch. 12 - A balanced delta-connected load is supplied by a...Ch. 12 - Design a problem to help other students better...Ch. 12 - A three-phase source delivers 4.8 kVA to a...Ch. 12 - A balanced wye-connected load with a phase...Ch. 12 - Three equal impedances, 60 + j30 each, are...Ch. 12 - A 4200-V, three-phase transmission line has an...Ch. 12 - The total power measured in a three-phase system...Ch. 12 - Given the circuit in Fig. 12.57 below, find the...Ch. 12 - Find the real power absorbed by the load in Fig....Ch. 12 - For the three-phase circuit in Fig. 12.59, find...Ch. 12 - A balanced delta-connected load draws 5 kW at a...Ch. 12 - A balanced three-phase generator delivers 7.2 kW...Ch. 12 - Refer to Fig. 12.48. Obtain the complex power...Ch. 12 - A three-phase line has an impedance of 1 + j3 per...Ch. 12 - A balanced wye-connected load is connected to the...Ch. 12 - A three-phase load consists of three 100-...Ch. 12 - The following three parallel-connected three-phase...Ch. 12 - A balanced, positive-sequence wye-connected source...Ch. 12 - Each phase load consists of a 20- resistor and a...Ch. 12 - A balanced three-phase source with VL = 240 V rms...Ch. 12 - Consider the wye-delta system shown in Fig. 12.60....Ch. 12 - A four-wire wye-wye circuit has...Ch. 12 - Using Fig. 12.61, design a problem that will help...Ch. 12 - A balanced three-phase Y-source with VP = 880 V...Ch. 12 - A three-phase supply, with the line-to-line...Ch. 12 - Using Fig. 12.63, design a problem to help other...Ch. 12 - Determine the line currents for the three-phase...Ch. 12 - Solve Prob. 12.10 using PSpice or MultiSim. For...Ch. 12 - The source in Fig. 12.65 is balanced and exhibits...Ch. 12 - Use PSpice or MultiSim to determine Io in the...Ch. 12 - Given the circuit in Fig. 12.67, use PSpice or...Ch. 12 - Using Fig. 12.68, design a problem to help other...Ch. 12 - Use PSpice or MultiSim to find currents IaA and...Ch. 12 - For the circuit in Fig. 12.58, use PSpice or...Ch. 12 - A balanced three-phase circuit is shown in Fig....Ch. 12 - A three-phase, four-wire system operating with a...Ch. 12 - As shown in Fig. 12.72, a three-phase four-wire...Ch. 12 - Meter readings for a three-phase wye-connected...Ch. 12 - A certain store contains three balanced...Ch. 12 - The two-wattmeter method gives P1=1200W and...Ch. 12 - In Fig. 12.73, two wattmeters are properly...Ch. 12 - If wattmeters W1 and W2 are properly connected...Ch. 12 - For the circuit displayed in Fig. 12.74, find the...Ch. 12 - Predict the wattmeter readings for the circuit in...Ch. 12 - Prob. 75PCh. 12 - Show that the I2R losses will be higher for a...Ch. 12 - A three-phase generator supplied 10 kVA at a power...Ch. 12 - Prob. 78CPCh. 12 - A balanced three-phase generator has an abc phase...Ch. 12 - A balanced three-phase source furnishes power to...Ch. 12 - A professional center is supplied by a balanced...Ch. 12 - A balanced three-phase system has a distribution...Ch. 12 - A commercially available three-phase inductive...Ch. 12 - Figure 12.76 displays a three-phase...Ch. 12 - Design a three-phase heater with suitable...Ch. 12 - For the single-phase three-wire system in Fig....Ch. 12 - Consider the single-phase three-wire system shown...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, electrical-engineering and related others by exploring similar questions and additional content below.Similar questions
- The instantaneous power absorbed by the load in a single-phase ac circuit, for a general R LC load under sinusoidal-steady-state excitation. is (a) Nonzero constant (b) Zero (c) Containing double-frequency componentsarrow_forwardTwo impedances consist of resistance of (15 ohms and series connectedinductance of 0.04 henry) and (resistance of 10 ohms, inductance of 0.1 henryand a capacitance of 100 microfarad, all in series) are connected in series andare connected to 230 volts, 50 – Hz AC source. Find: (a) current drawn, (b) voltageacross each impedance, (c) individual and total power factor. Draw the phasordiagram.arrow_forwardPower factor correction is a method to do which of the following.arrow_forward
- There are two loads connected in parallel and powered from a 7200-V source. The first load is 50-kVA at 0.9 power factor lagging, and the second load is 45-kW at 0.85 power factor lagging. Determine the kind of KVAR and capacitance required to correct the overall power factor to 0.96 lagging.arrow_forwardTwo impedances are connected in parallel to the supply, the first takes a current of 40 A at a lagging phase angle of 30°, and the second a current of 30 A at a leading phase angle of 45°. Draw a phasor diagram to scale to represent the supply voltage and these currents. From this diagram, by construction, determine the total current taken from the supply and its phase angle.arrow_forward8. The total power supplied to a balance delta load is found in the same way as for a balance wye load. True False Either Neither 12. A load of 20 + j35 ohms is connected across a 220 V, 60 Hz supply. Find the reactive power of the load in var. 595 2420 1042 1382 13. A type of DC source where the characteristic output voltage has perfect unidirectional waveform and is based on electrochemical principle. Generator Inverter Converter Battery 14. Calculate the Rf of a circuit whose impedance is 20+j35 and current of 2A. 0.86 0.91 0.50 0.71 15. What capacitor shall be installed in parallel with a circuit to achieve a unity power factor if the reactive power of a circuit is 200VARS and the voltage is 100V. 80.45 microfarad 53.05 microfarad It's already in unity 62.45 microfaradarrow_forward
- The circuit shows an unbalanced electrical installation powered by a positive sequence symmetrical three-phase network of 380 V compound voltage. The loads are single phase. Load 1 absorbs an active power of 950 W with f.d.p. 0.5 inductive. Load 2 absorbs an active power of 1,140 W with f.d.p. Unit. Load 3 absorbs from the network an active power of 760 W with f.d.p. 0.5 capacitive. Taking the network voltage URN as the phase reference, calculate: a) complex expressions of the line currents IR. Is. and ITarrow_forwardThe circuit shows an unbalanced electrical installation powered by a positive sequence symmetrical three- phase network of 380 V compound voltage. The loads are single phase. Load 1 absorbs an active power of 950 W with f.d.p. 0.5 inductive. Load 2 absorbs an active power of 1,140 W with f.d.p. Unit. Load 3 absorbs from the network an active power of 760 W with f.d.p. 0.5 capacitive. Taking the network voltage URN as the phase reference, calculate: a) complex expressions of the line currents IR. Is. and IT RO- SO TO IR Is IT U₁-380 V CARGA 1 P₁ =950 W cos p1=0,5 ind. CARGA 2 P₂=1.140 W cos p₂=1 CARGA 3 P3=760 W cos p3=0,5 cap.arrow_forwardA load has a leading power factor. a) Is it a capacitive or inductive load? b) Is the reactive power positive or negative? c) Repeat for a load with lagging power factorarrow_forward
- There is an installation with two equal triphasic loads of 300 kVA each and a power factor of 0.9 lagging. When connecting a pure reactive element in parallel, the reactive power at the entrance of the installation is 150 kVARS, with a lagging power factor. We can say that: a) A bank of reactors was connected and the fp deteriorated. b) A capacitor bank was connected and the pf deteriorated. c) A bank of reactors was connected and the fp improved. d) A capacitor bank was connected and the pf improved. e) None of the abovearrow_forwardThere is an installation with two identical three-phase motors, 50 HP each and a power factor of 0.9 behind. When connecting a pure reactive element in parallel, the reactive power at the installation input is 50 kVARS, with a lagging power factor. We can say that: a) A capacitor bank was connected and the pf improved. b) A bank of inductors was connected and the pf improved. c) A capacitor bank was connected and the pf deteriorated. d) A bank of inductors was connected and the pf deteriorated. e) None of the above.arrow_forwardA 30-0 resistor, a 15-02 inductive reactance, and a 12-02 capacitive reactance are connected in parallel across a 120-V 60-Hz line. Find (a) the phasor branch currents, (b) total current and phase angle, (c) impedance, and (d) power drawn by the circuit.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Power System Analysis and Design (MindTap Course ...Electrical EngineeringISBN:9781305632134Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. SarmaPublisher:Cengage LearningDelmar's Standard Textbook Of ElectricityElectrical EngineeringISBN:9781337900348Author:Stephen L. HermanPublisher:Cengage Learning
Power System Analysis and Design (MindTap Course ...
Electrical Engineering
ISBN:9781305632134
Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma
Publisher:Cengage Learning
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:9781337900348
Author:Stephen L. Herman
Publisher:Cengage Learning
What is the Difference Between Single Phase and Three Phase???; Author: Electrician U;https://www.youtube.com/watch?v=FEydcr4wJw0;License: Standard Youtube License