Abstract: Ground fault detection circuitry for sensing ground fault currents is dissed. If ground fault occurs in a line conductor(s) in a distribution system supplying AC power to a load, the circuitry senses this ground fault and provides a signal in response to the sensing of the ground fault. The circuitry also senses the grounding of a neutral conductor, or in some systems the shorting of a line conductor by a parallel conductive path and provides a signal in response to the grounding of the neutral or the parallel conductive shorting path. The signals provided by the circuitry in response to these sensed conditions may be used to provide a visual or audible alarm, or may be used to remove power from the load.