Interview Questions Answers in Electrical Engineering

ahmed soliman

{ City } cairo
< Country > egypt
* Profession * electrical
User No # 99742

Total Questions Posted # 0
Total Answers Posted # 1

Total Answers Posted for My Questions # 0
Total Views for My Questions # 0

Users Marked my Answers as Correct # 1
Users Marked my Answers as Wrong # 0

Questions / { ahmed soliman }

Questions Answers Category Views Company eMail

Answers / { ahmed soliman }

Question { Qatar Gas, 4314 }

Why Diffrential and Ref relays are used together although
Diffrential relay can protect Pri and Sec of Transformer

Answer

The normal bias setting in a differential relay is 20%.
So, complete earth fault protection is not possible with
differential relay. That is why you need a seperate earth
fault relay with sensitive settings like 5%.

Is This Answer Correct ?

1 Yes

0 No