Answer / ramniveth

the usual procedure for transmission is star to delta

for ex: 220KV/33KV
if they transmit 33KV then 33KV will be in star side and
vice versa

in this case say a delta is transmitted and gets an earth
fault .Zero sequence current will be flowing only in the
transformer .
fault current of phase which gets earthed with earth will
be almost zero .because no return path .
voltage becomes zero for the fault phase and the other two
healthy phases voltage gets root three times incresed which
may affect the whole system

when any relay trips in any ckt then what type of setting is there in motor?what is function of relay in that ckt?

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