Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...


Why Neutral Busbar CT & transformer neutral CT connected
with phase CT in Restricted Earth Fault?

Answers were Sorted based on User's Feedback



Why Neutral Busbar CT & transformer neutral CT connected with phase CT in Restricted Earth Fau..

Answer / vinod g

In Restricted earth fault protection Three phase CT is
parralleling (shorting all S1 andshorting all S2 together)
and paralleel conection with Neutral Relay and CT. IN
Healthy conditon current in all the three phase will be
balanced and summation will be zero. During earth fault out
side CT area summation of phase CT currents and Neutral CT
zero, so relay will not pick up. When earth fault inside
the transformer the current in the CT will differ and Relay
will pick and trip the tranformer breaker,so it is clear
that REF is for Transformer Winding protection and Bushing
CT is normally using for phase CT

Is This Answer Correct ?    3 Yes 0 No

Why Neutral Busbar CT & transformer neutral CT connected with phase CT in Restricted Earth Fau..

Answer / pintu

THIS IS CALLED 5 CT CONFIGURATION (3 PH. CT + 1 X'MER NCT +
1 BB N CT)OF REF PROTECTION. ALL THESE FIVE CTS ARE TO BE
CONNECTED IN PARALLEL. TRANSFORMER NCT SHOULD BE LOCATED
AFTER NEUTRAL BIFERCATION (I.E. PATH TOWARDS EARTH) AS THIS
IS DEDICTAED FOR DETECTING THE RESIDUAL CURRENT IN CASE OF
GROUND FAULT. BUT NEUTRAL BUSBAR CT IS NOT FOR DETECTING
THE FAULT CUURENT BUT FOR THE UNBALANCE CURRENT IN THE
SYSTEM. IT SHOULD NOT BE TRIPPED DURING THE EARTH FAULT.

IN 4 CTS CONFIGURATION OF REF PROTECTION, NEUTRAL BUSBAR CT
CONNECTION WILL NOT BE THERE. YOU SHOULD DECIDE THE 5 OR 4
CT CONFIGURATION AS PER YOUR SYSTEM DESIGN.

Is This Answer Correct ?    3 Yes 2 No

Why Neutral Busbar CT & transformer neutral CT connected with phase CT in Restricted Earth Fau..

Answer / anup mahajan

The purpoae of Restricted earth fault (REF) is to provide
the protection of transformer neutral in case of residual
current. As the fault which lies near phases are known as
external faults and is to be detected by differential
protection but the residual current which is not going to
ground and circulates between neutral and phases are
detedted by REF protection. Please keep in mind that CT
characteristics of this REF must be matched with phase side
CT characteristics.

Is This Answer Correct ?    2 Yes 8 No

Post New Answer

More Electrical Engineering Interview Questions

what is the difference between KW and KVA?

15 Answers  


what is legal process of dg set?

0 Answers   Dutron Polymers,


how the percentage impedance affect the transformer loading when connected in parallel.?

1 Answers  


What is the name of the winding to which supply is given?

0 Answers  


for 12KW motor which cable size has to select for ex.10 meter.

4 Answers  


what is Use of Stones/Gravel in electrical Switch Yard??

4 Answers   Sanghi,


what is function of centrifugal switch in single phase induction motor..?

3 Answers  


when a primary current injection test is required, it is accomplished by what?

3 Answers  


What is the working of AVR in AC generators?

13 Answers   Navrachana University,


what is the minimum winding resistance of 30hp compressor, to run or to switch on

0 Answers  


In Electrical 'Single Line Diagram' cable nomenclature shows "2 X 1C X 630sq.mm to be provided for one incomer. The question is how many cable to be proved for one Incomer.

0 Answers  


WHY AREWE USING THE 3 1/2 CORE CABLES IN POWER TRANSMISSION

1 Answers   Phoenix Technologies,


Categories
  • Civil Engineering Interview Questions Civil Engineering (5086)
  • Mechanical Engineering Interview Questions Mechanical Engineering (4456)
  • Electrical Engineering Interview Questions Electrical Engineering (16639)
  • Electronics Communications Interview Questions Electronics Communications (3918)
  • Chemical Engineering Interview Questions Chemical Engineering (1095)
  • Aeronautical Engineering Interview Questions Aeronautical Engineering (239)
  • Bio Engineering Interview Questions Bio Engineering (96)
  • Metallurgy Interview Questions Metallurgy (361)
  • Industrial Engineering Interview Questions Industrial Engineering (259)
  • Instrumentation Interview Questions Instrumentation (3014)
  • Automobile Engineering Interview Questions Automobile Engineering (332)
  • Mechatronics Engineering Interview Questions Mechatronics Engineering (97)
  • Marine Engineering Interview Questions Marine Engineering (124)
  • Power Plant Engineering Interview Questions Power Plant Engineering (172)
  • Textile Engineering Interview Questions Textile Engineering (575)
  • Production Engineering Interview Questions Production Engineering (25)
  • Satellite Systems Engineering Interview Questions Satellite Systems Engineering (106)
  • Engineering AllOther Interview Questions Engineering AllOther (1379)