NOVELTY - A system comprises an enclosure; a first terminal assembly for receiving a conductor of a first polarity from photovoltaic elements; a second terminal assembly (30) for receiving a conductor of a second polarity from the photovoltaic elements, and comprising a busbar (40) having a central conductive body, elongated fingers, and over-current protection elements; and#hall effect sensors to detect variations in the current flowing through one of the busbar fingers.    USE - A system for combining direct current power produced by photovoltaic elements (claimed) including solar panels or solar panel arrays.    DETAILED DESCRIPTION - A system comprises:    (A) an enclosure;    (B) a first terminal assembly for receiving a conductor of a first polarity from photovoltaic elements, where the first terminal assembly is disposed within the enclosure;    (C) a second terminal assembly (30) for receiving a conductor of a second polarity from the photovoltaic elements, where the second polarity is opposite the first polarity, and the second terminal assembly is disposed in the enclosure, and where the second terminal assembly comprises a busbar (40) in electrical communication with each of the conductors of a second polarity from the photovoltaic elements so that the direct current from the photovoltaic elements is combined to form a single current at the busbar, where the busbar comprises a central conductive body, elongated fingers projecting outwardly from the central conductive body, over-current protection elements each connected to one of the conductors of a second polarity from the photovoltaic elements and one of the fingers of the busbar, where the over-current protection elements are operable to break the circuit between the busbar and the respective power producing photovoltaic element in the event the current from photovoltaic element exceeds a threshold, and where the fingers of the busbar are elongated to space the central conductive body of the busbar away from the over-current protection elements when the busbar fingers are connected with the over-current protection elements; and    (D) hall effect sensors spaced apart from one another and positioned adjacent a separate one of the busbar fingers so that each sensor is operable to detect variations in the current flowing through one of the busbar fingers.    DESCRIPTION OF DRAWING(S) - The drawing is a perspective view of a positive input assembly of the system.    Second terminal assembly (30)    Busbar (40)    Sensor assembly (60)    Insulative layer (66)    base plate (80)