Leakage detector for determining possible shock hazards to humans

Claim 1

A leakage detector for determining possible shock hazards to humans from exposed, accessible parts of electrically operating apparatus which are not normally intended to carry electrical voltages, comprising: a full wave rectifier circuit having an input terminal, an output terminal, a reference terminal and an intermediate terminal; first means for directly connecting the reference terminal of said rectifier circuit to a point of ground potential; second means for adaptively contacting the input terminal of said rectifier circuit with various ones of said exposed parts in determining the presence thereat of any such unintended voltages; a direct current milliammeter; and a first resistor coupling one terminal of said milliammeter to the output terminal of said rectifier circuit, the intermediate terminal of which is direct current coupled to a second terminal of said milliammeter, and with said first resistor being of a resistance value approximating the body resistance of a human being; whereby said direct current milliammeter provides an indication of the direct current which would be caused to flow through said resistor due to the presence of any unintended voltages on those exposed parts contacted by said second means, and an indication of the direct current which would pass through a human being who would come into physical contact with said energized parts unless measures were taken to correct such electrical leakages.