| CPC H02H 3/105 (2013.01) [H02H 3/283 (2013.01)] | 24 Claims |
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1. A system for modifying a trip level of a circuit, the system comprising:
a protection device configured to activate responsive to a differential current exceeding the trip level;
a first current transformer coupled to an input of the circuit;
a second current transformer coupled to the output of the circuit;
at least one measurement circuit coupled to the first current transformer and to the second current transformer, the at least one measurement circuit being configured to
obtain a first current measurement from the first current transformer,
obtain a second current measurement from the second current transformer,
determine a bias current based on the first current measurement and the second current measurement, and
modify the trip level of the protection device by a bias value, the bias value being based on a maximum of the differential current, a previously determined bias value, and a multiple of a change in the bias current.
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