what is the differnce between high impedance relay and low
impedance relay
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Answer Posted / chander, ak
High impedance principle means that protective relay has a
such a large series impedance that even the largest through
fault current occuring during transient condition does not
start an un-necessary relay operation.High impedance relay
is one in which all CTs must have the same ratios. it is
employed in The differential protection of generators, bus
bars, motors and reactors.
Low impedance relays do not have any additional series
impedances and are usually employed for transformers
differential protection.
| Is This Answer Correct ? | 12 Yes | 8 No |
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