Homework Help is Here – Start Your Trial Now!
Engineering
Electrical Engineering
SECTION B-Choose any TWO (2) Questions from this Section Question 1 [25 Marks] (a) A commercial building has a power demand of 50 kW at a power factor of 85%. Determine (i) (ii) The annual penalty if the utility's minimum power factor is 95% and the cost of power is P10/kW/month (9) P The cost of capacitor, which when connected in parallel to the load will improve the power factor to 100%. (Assume the purchasing cost of capacitor is P30/kVAR) (10) (b) A 3-phase, 10 kVA load has a power factor of 0.342. The power is measured by two wattmeter method. Find the reading of each wattmeter. Q w Var Va = 10€ Va >= 10kVA pl: 0.36 2 (= Isine 5 3149 Question 2 [25 Marks] (a) A single-phase motor takes apparent power of 1909 VA at a power factor of 0.866 lagging when con- nected to a 230 V, 50 Hz supply. (i) Calculate current drawn from the supply (ii) (b) Draw a fully labelled equivalent circuit of a transformer Two similar capacitors are then connected in parallel with each other to form a capacitance bank. The capacitor bank is now connected in parallel with the motor to raise the power factor to 0.95. Calculate the capacitance of each capacitor.. (2) Cif (tune (14) (8) Question 3 [25 Marks] Quy (a) A cable is required to supply current from a 110 V a.c. source to a welding set. The welding set has a power factor of 0.6 lagging and taking a current of 200 A from the source. The only avail- able cable has a rating of 150 A, and it is decided to use this cable by installing a capacitor across the terminals of the welding set. (i) Calculate the capacitive current required to limit the cable current to 150 A. (i) Draw a fully labelled vector diagram showing all currents (8) (6) (b) A 3-phase, 400 V source is supplying power to a balanced 3-phase delta connected 12 kW load and the line current is 30 A. If the same load is connected in star find (i) Line current IL (ii) Power factor pl V (iii) Power consumed (4) (3) (4) Io I a lave = tan" Pelts (13 (PLA)) p=0.6 I 200 12kW I₁ = 30A Zp ACI 130L Star Page 3 of 3 Ic Si, Tou

SECTION B-Choose any TWO (2) Questions from this Section Question 1 [25 Marks] (a) A commercial building has a power demand of 50 kW at a power factor of 85%. Determine (i) (ii) The annual penalty if the utility's minimum power factor is 95% and the cost of power is P10/kW/month (9) P The cost of capacitor, which when connected in parallel to the load will improve the power factor to 100%. (Assume the purchasing cost of capacitor is P30/kVAR) (10) (b) A 3-phase, 10 kVA load has a power factor of 0.342. The power is measured by two wattmeter method. Find the reading of each wattmeter. Q w Var Va = 10€ Va >= 10kVA pl: 0.36 2 (= Isine 5 3149 Question 2 [25 Marks] (a) A single-phase motor takes apparent power of 1909 VA at a power factor of 0.866 lagging when con- nected to a 230 V, 50 Hz supply. (i) Calculate current drawn from the supply (ii) (b) Draw a fully labelled equivalent circuit of a transformer Two similar capacitors are then connected in parallel with each other to form a capacitance bank. The capacitor bank is now connected in parallel with the motor to raise the power factor to 0.95. Calculate the capacitance of each capacitor.. (2) Cif (tune (14) (8) Question 3 [25 Marks] Quy (a) A cable is required to supply current from a 110 V a.c. source to a welding set. The welding set has a power factor of 0.6 lagging and taking a current of 200 A from the source. The only avail- able cable has a rating of 150 A, and it is decided to use this cable by installing a capacitor across the terminals of the welding set. (i) Calculate the capacitive current required to limit the cable current to 150 A. (i) Draw a fully labelled vector diagram showing all currents (8) (6) (b) A 3-phase, 400 V source is supplying power to a balanced 3-phase delta connected 12 kW load and the line current is 30 A. If the same load is connected in star find (i) Line current IL (ii) Power factor pl V (iii) Power consumed (4) (3) (4) Io I a lave = tan" Pelts (13 (PLA)) p=0.6 I 200 12kW I₁ = 30A Zp ACI 130L Star Page 3 of 3 Ic Si, Tou

Introductory Circuit Analysis (13th Edition)
Introductory Circuit Analysis (13th Edition)
13th Edition
ISBN:9780133923605
Author:Robert L. Boylestad
Publisher:Robert L. Boylestad
Chapter1: Introduction
Section: Chapter Questions
Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...
See similar textbooks
icon
Related questions
Question
SECTION B-Choose any TWO (2) Questions from this Section Question 1 [25 Marks] (a) A commercial building has a power demand of 50 kW at a power factor of 85%. Determine (i) (ii) The annual penalty if the utility's minimum power factor is 95% and the cost of power is P10/kW/month (9) P The cost of capacitor, which when connected in parallel to the load will improve the power factor to 100%. (Assume the purchasing cost of capacitor is P30/kVAR) (10) (b) A 3-phase, 10 kVA load has a power factor of 0.342. The power is measured by two wattmeter method. Find the reading of each wattmeter. Q w Var Va = 10€ Va >= 10kVA pl: 0.36 2 (= Isine 5 3149 Question 2 [25 Marks] (a) A single-phase motor takes apparent power of 1909 VA at a power factor of 0.866 lagging when con- nected to a 230 V, 50 Hz supply. (i) Calculate current drawn from the supply (ii) (b) Draw a fully labelled equivalent circuit of a transformer Two similar capacitors are then connected in parallel with each other to form a capacitance bank. The capacitor bank is now connected in parallel with the motor to raise the power factor to 0.95. Calculate the capacitance of each capacitor.. (2) Cif (tune (14) (8) Question 3 [25 Marks] Quy (a) A cable is required to supply current from a 110 V a.c. source to a welding set. The welding set has a power factor of 0.6 lagging and taking a current of 200 A from the source. The only avail- able cable has a rating of 150 A, and it is decided to use this cable by installing a capacitor across the terminals of the welding set. (i) Calculate the capacitive current required to limit the cable current to 150 A. (i) Draw a fully labelled vector diagram showing all currents (8) (6) (b) A 3-phase, 400 V source is supplying power to a balanced 3-phase delta connected 12 kW load and the line current is 30 A. If the same load is connected in star find (i) Line current IL (ii) Power factor pl V (iii) Power consumed (4) (3) (4) Io I a lave = tan" Pelts (13 (PLA)) p=0.6 I 200 12kW I₁ = 30A Zp ACI 130L Star Page 3 of 3 Ic Si, Tou
Transcribed Image Text:SECTION B-Choose any TWO (2) Questions from this Section Question 1 [25 Marks] (a) A commercial building has a power demand of 50 kW at a power factor of 85%. Determine (i) (ii) The annual penalty if the utility's minimum power factor is 95% and the cost of power is P10/kW/month (9) P The cost of capacitor, which when connected in parallel to the load will improve the power factor to 100%. (Assume the purchasing cost of capacitor is P30/kVAR) (10) (b) A 3-phase, 10 kVA load has a power factor of 0.342. The power is measured by two wattmeter method. Find the reading of each wattmeter. Q w Var Va = 10€ Va >= 10kVA pl: 0.36 2 (= Isine 5 3149 Question 2 [25 Marks] (a) A single-phase motor takes apparent power of 1909 VA at a power factor of 0.866 lagging when con- nected to a 230 V, 50 Hz supply. (i) Calculate current drawn from the supply (ii) (b) Draw a fully labelled equivalent circuit of a transformer Two similar capacitors are then connected in parallel with each other to form a capacitance bank. The capacitor bank is now connected in parallel with the motor to raise the power factor to 0.95. Calculate the capacitance of each capacitor.. (2) Cif (tune (14) (8) Question 3 [25 Marks] Quy (a) A cable is required to supply current from a 110 V a.c. source to a welding set. The welding set has a power factor of 0.6 lagging and taking a current of 200 A from the source. The only avail- able cable has a rating of 150 A, and it is decided to use this cable by installing a capacitor across the terminals of the welding set. (i) Calculate the capacitive current required to limit the cable current to 150 A. (i) Draw a fully labelled vector diagram showing all currents (8) (6) (b) A 3-phase, 400 V source is supplying power to a balanced 3-phase delta connected 12 kW load and the line current is 30 A. If the same load is connected in star find (i) Line current IL (ii) Power factor pl V (iii) Power consumed (4) (3) (4) Io I a lave = tan" Pelts (13 (PLA)) p=0.6 I 200 12kW I₁ = 30A Zp ACI 130L Star Page 3 of 3 Ic Si, Tou
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Recommended textbooks for you
Introductory Circuit Analysis (13th Edition)
Introductory Circuit Analysis (13th Edition)
Electrical Engineering
ISBN:
9780133923605
Author:
Robert L. Boylestad
Publisher:
PEARSON
Delmar's Standard Textbook Of Electricity
Delmar's Standard Textbook Of Electricity
Electrical Engineering
ISBN:
9781337900348
Author:
Stephen L. Herman
Publisher:
Cengage Learning
Programmable Logic Controllers
Programmable Logic Controllers
Electrical Engineering
ISBN:
9780073373843
Author:
Frank D. Petruzella
Publisher:
McGraw-Hill Education
Fundamentals of Electric Circuits
Fundamentals of Electric Circuits
Electrical Engineering
ISBN:
9780078028229
Author:
Charles K Alexander, Matthew Sadiku
Publisher:
McGraw-Hill Education
Electric Circuits. (11th Edition)
Electric Circuits. (11th Edition)
Electrical Engineering
ISBN:
9780134746968
Author:
James W. Nilsson, Susan Riedel
Publisher:
PEARSON
Engineering Electromagnetics
Engineering Electromagnetics
Electrical Engineering
ISBN:
9780078028151
Author:
Hayt, William H. (william Hart), Jr, BUCK, John A.
Publisher:
Mcgraw-hill Education,
SEE MORE TEXTBOOKS