Why CTs are connected in star on T/F delta connected winding side & in delta on T/F star connected winding side for T/F differential protection?
I don’t understand the question. Can you restate it without using abbreviations? “CT” and “T/F” don’t mean anything obvious to me.
Why Current transformers are connected in star on Transformer delta connected winding side & in delta on Transformer star connected winding side for Transformer differential protection?
(I think its quite clear now)
Sorry, I don’t find it at all clear. I’m not sure I can even see a question there. It’s just a bunch of words that don’t seem to form a coherent sentence to me. That might be because I don’t know anything about what you’re asking, and it’s possible that someone else who understands current transformers and star connections would be able to answer you.
A schematic (picture) might be helpful.
Also there is a language barrier here…two people speaking different versions of English.
Brings back my old EE classes in college… I think the question is looking for the rationale behind the old rule of thumb that “CTs on any wye winding of a power transformer should be connected in delta, and CTs on any delta winding should be connected in wye”. (Replace wye with star if you are in Europe). Try this reference and see if it doesn’t help (starting on page 212)… My apologies if I misinterpreted the question.