Human impedance characteristic investigation by low voltage square wave excitation

In order to obtain the characteristic of the human impedance [1][2], A square wave electric signal is proposed to apply to the human beings. The peak current when a human is in initial contact of an electrical signal is examined. The use of square wave is a better method for human detection as it gives an exponential current that is unique as compared to another electrical appliance. The result provides a critical judgment for smart electric socket which could identify human being from another appliance. The whole research is based on the human model in the standard of IEC 479[3]. Considering the instant effect in the first charging moment by the step pulse, the human model is simplified to an RC circuit.