Patent ID: 7529069

Claim:
A ground fault detection and location system comprising: a ground fault main unit, said ground fault main unit comprising a frequency generator, said frequency generator generating an oscillating ground current in a normally ungrounded circuit at a pre-determined target AC frequency; a low-noise pre-amp; a ground fault location apparatus, said ground fault location apparatus comprising: a bandpass filter coupled to said low-noise pre-amp; a bias floating ground coupled to said resonating capacitor and said bandpass filter; a diode coupled to said bias floating ground; a signal level display coupled to said diode; a comparator with hysterisis coupled to said bandpass filter; a low pass filter coupled to said bandpass filter and said comparator with hysterisis; and an internal power supply; a resonating capacitor coupled to said low-noise pre-amp, said resonating capacitor and said low-noise pre-amp being configured to amplify a current signal, thereby creating an amplified current signal; a communication link coupling said frequency generator to said ground fault location apparatus; and a current transformer, said current transformer being selectively coupled to said ground fault location apparatus, said current transformer monitoring said oscillating ground current and locating a ground fault by detecting said target AC frequency.