Abstract: A detection circuit detects a difference between a source current and a return current. The detection circuit includes a constantly biased magnetic core through which conductors of the source and return currents extend, and a sense winding around the core. The sense winding carries an AC signal. A sensing circuit connected with the sense winding senses a change in small signal impedance of the sense winding relative to the core. This detection circuit can be used to protect people and equipment against accidental contact with high-voltage DC systems.

Abstract: An embodiment of the present invention pertains to a multiple discharge load electronic ballast system, including a distribution bus and a plurality of electronic ballasts. The distribution bus has a nominal distribution power rating. The plurality of electronic ballasts are operatively coupled to the distribution bus. A respective electronic ballast comprises adaptations for DC voltage control and an alternating current (AC) output, and has a maximum ballast power rating. A sum of the maximum ballast power ratings of the plurality of electronic ballasts is greater than the nominal distribution power rating of the distribution bus.