Why we not use the impedance relay in protection of short transmission line ?

Answer Posted / pritish

in case of short transmission line, the protection due to arc resistance is the major factor. hence , the relay should be selected which is less affected to arc resistance. and according to R-X diagram of impedance and reactance relay, the area of reactance relay is more and it is less affected to arc resistance fault but impedance relay is moderately affected due to arc resistance. so reactance relay is used in a short transmission line.


for more clarification, please email to pritish.nath@gmail.com

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