Patent ID: 9063184
Filing Date: 2015-06-23
Classification: G01R

Abstract:
1. A sensor for sensing an electric potential on a wire of a power distribution system and a current passing through the wire, the sensor comprising: a sensor clamp body including a pair of handles disposed at a proximal end thereof and a hinge mechanism coupling the pair of handles, so that compressing the pair of handles opens an aperture at a distal end of the sensor clamp body for receiving the wire, and wherein the hinge mechanism includes a restoring spring to close the aperture around the wire when the pair of handles is released; a current-sensing device disposed within the sensor clamp body for providing a first output indicative of the current passing through the wire; a voltage-sensing device integrated in the sensor clamp body for providing a second output indicative of the electric potential on the wire, wherein the voltage-sensing device and the current-sensing device do not make electrical contact with the wire, wherein the voltage-sensing device has a first terminal for providing the second output and a second terminal; and a selector circuit coupled to the voltage-sensing device for selecting between a measurement mode and a calibration mode, wherein in the calibration mode, the selector circuit couples the first terminal and the second terminal of the voltage-sensing device to a current source that causes a calibration current of predetermined magnitude to be conducted through the voltage-sensing device and to a current-measuring circuit that measures the first output of the current-sensing device to obtain a current measurement calibration value when the selector circuit selects the calibration mode, and wherein when the selector circuit selects the measurement mode, the current-measuring circuit adjusts a value of the first output in conformity with the current measurement calibration value.