Patent ID: 8659286

Claim:
A self-calibrating system for measuring a quantity of electrical current flowing through an electrical conductor included in an electrical circuit, the system comprising: a calibration signal generator (“CSG”), configured for coupling to the electrical circuit, the CSG being able to at least one of draw current from and add current to the electrical conductor so as to impose an automatically repeated calibration signal including a time-varying current fluctuation of known strength and time variation pattern onto the current flowing through the electrical conductor; a current sensor which, when placed in sensory communication with the electrical conductor, produces a sensor output signal having a signal strength which is related to the quantity of electrical current flowing through the electrical conductor; and a receiver which is able to receive the sensor output signal, distinguish according to the known time variation pattern of the calibration signal a component of the sensor output signal which corresponds to the calibration signal, and calibrate the sensor output signal according to the known strength of the calibration signal so as to determine the quantity of current flowing through the electrical conductor.