Homework Help is Here – Start Your Trial Now!
Engineering
Electrical Engineering
Distinguish the drawbacks of electromechanical type protective relay against the digital type protective relay.

Distinguish the drawbacks of electromechanical type protective relay against the digital type protective relay.

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
icon
Concept explainers
Question

Both questions please. Thank you 

Question 4 (a) Distinguish the drawbacks of electromechanical type protective relay against the digital type protective relay. (b) An 11 kV, 50 Hz radial system is shown in Figure 6. Assume a CO-7 overcurrent protective relay with characteristic given in Figure 7. By using different power factor for all loads (in the range of 0.8 - 0.9), design suitable relay settings (current tap setting, time dial setting) and coordination design to protect the system with time interval of 0.3 seconds. 3 2 I32, 1 11 kV C.T.R=400/5 C.T.R=200/5 C.T.R=200/5 %3D Figure 6: Simple radial network :7 MW, Short circuit rating at bus 3 (Isc3) = 4kA :3 MW, Short circuit rating at bus 2 (Isc2) = 3kA :4 MW, Short circuit rating at bus 1 (Isc1) = 2kA Load at bus 3 %3D Load at bus 2 Load at bus 1 Typical time curves type CO-7 over current relay 50–60 cycles Current tap settings: 4,5,6,7,8,10,12 amperes Time dial setting 10 2 1/2 2 3 4 5 6 7 8 9 10 12 14 16 18 20 Current as a multiple of tap setting Figure 7: CO-7 Overcurrent Protective Relay Time vs Current Curve Operating time in seconds
Transcribed Image Text:Question 4 (a) Distinguish the drawbacks of electromechanical type protective relay against the digital type protective relay. (b) An 11 kV, 50 Hz radial system is shown in Figure 6. Assume a CO-7 overcurrent protective relay with characteristic given in Figure 7. By using different power factor for all loads (in the range of 0.8 - 0.9), design suitable relay settings (current tap setting, time dial setting) and coordination design to protect the system with time interval of 0.3 seconds. 3 2 I32, 1 11 kV C.T.R=400/5 C.T.R=200/5 C.T.R=200/5 %3D Figure 6: Simple radial network :7 MW, Short circuit rating at bus 3 (Isc3) = 4kA :3 MW, Short circuit rating at bus 2 (Isc2) = 3kA :4 MW, Short circuit rating at bus 1 (Isc1) = 2kA Load at bus 3 %3D Load at bus 2 Load at bus 1 Typical time curves type CO-7 over current relay 50–60 cycles Current tap settings: 4,5,6,7,8,10,12 amperes Time dial setting 10 2 1/2 2 3 4 5 6 7 8 9 10 12 14 16 18 20 Current as a multiple of tap setting Figure 7: CO-7 Overcurrent Protective Relay Time vs Current Curve Operating time in seconds
Expert Solution
steps

Step by step

Solved in 3 steps

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Thermistors
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.
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