Answer / nur.asidik

differential/87G-need two sets of CTs, coverage are protection is only area between CT,
overcurrent/50,51--only need 1set CTs, Relay trip CB regardless fault location

Answer / raj

Differential protection relating to Voltage induced in the alternator with prescribed limit(In Common words. the protection circuit is used to trip the generator when over voltage is produced by the generator)
The over Current Protection is used on the output side( at terminal) of the generator ( when the load is exceed with limit of the alternator then it will trip the O/P ckt for safe limit of the generator

length of 4 core cable 95mm from substation LV VFD panel to Motor at field approximately 150 meter. Motor stop and power has been isolated from LV MCC ( Substation )to disconnect Motor for services. After Motor completed service propose to reinstall and reconnect Motor Cable, found earth cable sparkling during touching at metal / motor body. Inspect by clamp meter found earth cable have current flow AC 1-2amps and all earth cable at MCC LV also have current flow as same value. why it is happen?

2 Answers  

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When i went to a interview the interviewer ask me a question for that i cant able to answer him if anyone knows answer me How will you design a capacitor bank for a plant? if my p.f is 0.6 i have to improve it to 0.9 or 1 what kind of steps i have to do? and is there any formula for calculating this?

2 Answers  

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I am applying for NTPC examination.Can we please provide previous paper to my mail prasad.chintala108340@gmail.com

0 Answers  

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What is the difference between "Earthing" and "Neutral"?

10 Answers   Power Grid,

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What is the reason of using bus-bars on the secondary on the LT transformers?

2 Answers  

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We have 11kV/110V three phase indoor potential transformer in 66/11kV Sub-station, where the failure of PT is frequently happening and the rating of the PT is 0.2 class accuracy, with primary star and seconday (two cores) star connected. Some experts has suggested to not to connect the PT Primary neutral to the ground because when transformer neutal NCT connection is loose; the faulty current will flow through the PT primary neutral, resulting into failure of PT. My question is: Is it necessary to remove the primary neutral connection of the PT from ground? if not, what would be the reason for failure of PT. Please guide me.

2 Answers   KPTCL,

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which transmission is cheaper ac or dc?

10 Answers  

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why alternator is used instead of dc generator and induction generator

1 Answers  

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hr round

0 Answers  

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What is Delta Connection? What is meant by Forward Delta & Reverse Delta & How Will be the Connection in Power Transformers?

0 Answers  

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my bachelors was done with EEE now i got admit in NU with CS as course. how to answer this qns 1) why u choose cs? 2) why u changed from eee to cs

0 Answers  

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what is transformer tap change HT side and LT side

1 Answers   Alstom, Sodexo,

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