Calculate the operation time of an overcurrent relay of (10 A , 3 seconds) that has a current setting of 1. The time setting multiplier is 60 %, which supplies a current through (200 / 2.5) CT (current transformer) at a fault current of 1000 A. Re-solve the problem if the time setting multiplier is 50 %. How do you explain the difference?

Calculate the operation time of an overcurrent relay of (10 A , 3 seconds) that has a current setting of 1. The time setting multiplier is 60 %, which supplies a current through (200 / 2.5) CT (current transformer) at a fault current of 1000 A. Re-solve the problem if the time setting multiplier is 50 %. How do you explain the difference?

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 10.27P

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