Patent ID: 8542469

Claim:
An electrical power system comprising: a feeder between a power source and an electrical load; a first current transformer positioned at a first location on the feeder, the first current transformer comprising a first shunt resistor electrically connected across the first current transformer; a second current transformer positioned at a second location on the feeder; and a control unit interposed between the first and second current transformers; the control unit interconnected with the first and second current transformers on current-monitoring loops independent from the feeder; the control unit responsive to a predetermined differential in feeder (DF) current between the first and second current transformers to disconnect the power source from the electrical load; and the control unit including a compensation network to reduce DF error resulting from the first shunt resistor electrically coupled across the first current transformer, the compensation network including a series resistor coupled with the second current transformer, the series resistor having a resistance value that, when added to a resistance value of wiring between the second current transformer and a burden resistor associated with the second current transformer, produces a net resistance value approximately equal to a wiring resistance between the first current transformer and a burden resistor associated with the first current transformer.