Protection Engineering Basics and Schemes Protection Engineering | Page 62

In delta connection line to line current is 1.732 times of line or phase current

I line to line = √3I line

For PT, we use delta connection, as line to line voltage and line or phase voltage remain same in it.

V line to line = V line

In PT we also use broken delta connection to detect residual voltage( 3V 0) In system, mostly employed in directional earth fault relays.

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