A series resistance is added to the over-current relay in a bus bar differential protection scheme which:

A series resistance is added to the over-current relay in a bus bar differential protection scheme which: a. Helps to develop some voltage across it which otherwise should appear across the relay and is dangerous b. Helps to dissipate some power which is needed by the relay to function properly c. Helps to counter the effects of CT saturation and lowers the pickup value of the relay d. All of the above 
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A series resistance is added to the over-current relay in a bus bar differential protection scheme which: a. Helps to develop some voltage across it which otherwise should appear across the relay and is dangerous b. Helps to dissipate some power which is needed by the relay to function properly c. Helps to counter the effects of CT saturation and lowers the pickup value of the relay d. All of the above 

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