there is a power transformer 66/11kV in delta-delta connection has 5 feeder com

there is a power transformer 66/11kV in delta-delta
connection has 5 feeder coming out from the secondary side.
One of the feeder in it normally loaded (loaded than other
feeder)and this feeder usually trips with double OCR causing
the bank transformer to trip. Now if the load of this feeder
is put on other transformer then that no problems occurs on
that transformer or the load. However normally all the
test(IR, PI, short ckt, open ckt,grounding test and other )
has been conducted for this but evertything transformer.....
I am not geting what is the actual problem...

Question Posted / ajit152007

2 Answers
5256 Views
I also Faced
E-Mail Answers

Answers were Sorted based on User's Feedback

there is a power transformer 66/11kV in delta-delta connection has 5 feeder coming out from the sec..

Answer / parin patel

This thing happened dew to %Z of transformer.lesser the %Z current supplied by transformer will be more.
example:- there are two transformer
transformer 1: 66/11 kv,%Z= 5% ,15 kVA
transformer 2: 66/11 kv,%Z= 7%, 15kVA
If load is constant(same), current supplied by transformer 1 at 11 kv is more than current supplied by transformer 2 at 11 kv.

In your case ,you have to check the value of feeder current when it's supplied by two different transformer.in both case it might be different.

Is This Answer Correct ?

0 Yes

0 No

there is a power transformer 66/11kV in delta-delta connection has 5 feeder coming out from the sec..

Answer / k.prakashchandra

More data is required for analysis.If the transformers are
of same capacity and relays are identical ,interchange the
relays of transformer banks and watch.

Is This Answer Correct ?

0 Yes

0 No

Post New Answer

More Electrical Engineering Interview Questions

present we are having 0.8pf but I want increase it up to 0.99 so what is the formula for it and how can i calculate?

3 Answers ABB,

how to calculate the fault in substation

0 Answers

Which Kind of machines(in terms of poles) give the smoothest DC

0 Answers

can any one suggest me the tilt angle of my solar pannel ?? or tell me how can i know the fix tilt angle of my solar pannel?? my cordinates are 31.503629,72.993164.

0 Answers

why booster transformer is used in sumpners test conducted on transformer????

0 Answers Cooper,

Can any body describe me why a soft starter is used for 6.6kv induction motor instead of VFD ?

1 Answers Cairn,

what is isochronous mod? what is voltage drop mode and p.f mode?

0 Answers ABB,

Neutral to earth and phase to earth voltage how much.

2 Answers

pls give proper discription of selection of transformer based on particular load.

1 Answers

plz tell me about for how many rating (for 500kva)how much current taken?

13 Answers

how does oil cools the transformer

3 Answers HBL Power Systems,

What are the different towers used in 132kv transmission line? what are the differences between the P,R,S towers used in 132KV and detailed explanation

0 Answers

For more Electrical Engineering Interview Questions Click Here