Ground fault interrupter circuit

A ground fault interrupter circuit for interrupting signals at a first frequency conducted to a load from a source in the presence of a path to ground for leakage current, said ground fault interrupter circuit comprising:

• oscillator means for generating signals at a second frequency, said oscillator means having feedback means including a parallel circuit with a predetermined Q at said second frequency, said parallel circuit being formed by a first capacitor coupled in parallel with first, second, and third conductors having an inductive impedance tuned to be resonant at said second frequency by said first capacitor, said first and second conductors having input terminals for receiving said signals at said first frequency and output terminals for coupling to said load;
• a second capacitor coupled between said first and second conductors to provide a low impedance path for signals at said second frequency and a high impedance path for signals at said first frequency, said predetermined Q of said parallel circuit being reduced when signals at said second frequency are conducted along a continuous path including said first and second conductors, said second capacitor and a path for said leakage current from said first conductor to said ground;
• and
• switching means coupled to said first and second conductors for interrupting signals conducted from said source to said load when said predetermined Q of said resonant circuit is reduced.