Explain differential protection scheme for busbars with neat sketch.

Explain differential protection scheme for busbars with neat sketch.
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1 Answer

Answer :

Differential Protection Scheme for Bus bar: 

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Under normal conditions, the sum of the currents entering the bus bar zone is equal to those leaving it and no current flows through the relay coil. If a fault occurs within the protected zone, the currents entering the bus will no longer be equal those leaving it. The difference of these currents will flow through the relay coil causing opening of circuit breaker of bus-bar.

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