In the following power system, overcurrent relay R₁2 is to provide primary protection to line 1-2and overcurrent relay R23 is to provide primary protection to line 2-3. For both relays the CTratio is 200:5. The min and max currents for faults on lines 1-2 and 2-3 are shown. Maximumload current is 200 A.3IF,minR12= 1.5kA=0.8kAR23F,minIF.max=4.0kAIF max= 2.7KAIf R₁2, R₂3 are inverse, time-delay overcurrent relays, what should their pickup current(secondary current) and time dial settings be if a minimum coordination time of 0.5 second isrequired? The relay operating characteristics are shown on the following page.

A relay is a protective device used for overcurrent protection it consists of a coil and magnet…

In the following power system, overcurrent relay R₁2 is to provide primary protection to line 1-2 and overcurrent relay R₂3 is to provide primary protection to line 2-3. For both relays the CT ratio is 200:5. The min and max currents for faults on lines 1-2 and 2-3 are shown. Maximum load current is 200 A. 3 IF.min 0.8kA R23 R12 IF.min IF,max = 1.5kA =4.0KA IF max = 2.7KA 1 ·+· If R₁2, R₂3 are inverse, time-delay overcurrent relays, what should their pickup current (secondary current) and time dial settings be if a minimum coordination time of 0.5 second is required? The relay operating characteristics are shown on the following page.

In the following power system, overcurrent relay R₁2 is to provide primary protection to line 1-2 and overcurrent relay R₂3 is to provide primary protection to line 2-3. For both relays the CT ratio is 200:5. The min and max currents for faults on lines 1-2 and 2-3 are shown. Maximum load current is 200 A. 3 IF.min 0.8kA R23 R12 IF.min IF,max = 1.5kA =4.0KA IF max = 2.7KA 1 ·+· If R₁2, R₂3 are inverse, time-delay overcurrent relays, what should their pickup current (secondary current) and time dial settings be if a minimum coordination time of 0.5 second is required? The relay operating characteristics are shown on the following page.

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

Chapter10: System Protection

Section: Chapter Questions

Problem 10.17P

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