Please answer in short like it definitely don't reject in shorts please.. c. Current transformers, of turns ratio 1200:1, are used as supply to a differential relay ofresistance 3.5 and setting current 1.5A. Given that the CTs have secondary resistancesof 20 and the resistance of the pilot wires between them and the relay is 1.8 2 and 2.5 2respectively. Determine the minimum value of a stabilising resistor which will ensurethat neither CT will saturate for a through fault current of 80 kA.

Given: Turns ratio=1200:1RL=1.8+2.5RL=4.3ΩSetting current, Is=1.5 AI=80 kARelay resistance,…

c. Current transformers, of turns ratio 1200:1, are used as supply to a differential relay of resistance 3.52 and setting current 1.5A. Given that the CTs have secondary resistances of 22 and the resistance of the pilot wires between them and the relay is 1.8 2 and 2.5 2 respectively. Determine the minimum value of a stabilising resistor which will ensure that neither CT will saturate for a through fault current of 80 kA.

c. Current transformers, of turns ratio 1200:1, are used as supply to a differential relay of resistance 3.52 and setting current 1.5A. Given that the CTs have secondary resistances of 22 and the resistance of the pilot wires between them and the relay is 1.8 2 and 2.5 2 respectively. Determine the minimum value of a stabilising resistor which will ensure that neither CT will saturate for a through fault current of 80 kA.

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter14: Phase Failure Relays

Section: Chapter Questions

Problem 1SQ: What is the purpose of phase failure relays?

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