Electrical switching apparatus and method employing active acoustic sensing to detect an electrical conductivity fault of a power circuit

An electrical switching apparatus for detecting an electrical conductivity fault of a power circuit, said electrical switching apparatus comprising:

• first and second lugs adapted to be electrically connected to said power circuit;
• a first acoustic coupler adapted to be acoustically coupled to said power circuit;
• a second acoustic coupler adapted to be acoustically coupled to said power circuit;
• separable contacts electrically connected in series between said first and second lugs;
• an operating mechanism adapted to open and close said separable contacts;
• an acoustic generator coupled to said second acoustic coupler, said acoustic generator being adapted to generate a first acoustic signal to said power circuit from said second acoustic coupler;
• an acoustic sensor coupled to said first acoustic coupler, said first acoustic coupler having a second acoustic signal which is operatively associated with the electrical conductivity fault of said power circuit, said acoustic sensor being adapted to output a sensed acoustic signal;
• and
• a circuit cooperating with said acoustic generator to generate said first acoustic signal, input the sensed acoustic signal and detect said electrical conductivity fault therefrom.