The Fig. shows the part of a typical power system. If for the discrimination, the time grading margin between the relays is 0.6 sec. calculate the time of operation of relay 1 and time setting multiplier for relay 2. The time setting multiplier of relay 1 is 0.3. C.B. 500/5 C.T. Relay 2 150 % C.B. 500/5 C.T. Relay 1 125 % F Fault current 4000 A

The Fig. shows the part of a typical power system. If for the discrimination, the time grading margin between the relays is 0.6 sec. calculate the time of operation of relay 1 and time setting multiplier for relay 2. The time setting multiplier of relay 1 is 0.3. C.B. 500/5 C.T. Relay 2 150 % C.B. 500/5 C.T. Relay 1 125 % F Fault current 4000 A

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 10.2P

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