A human body has a surface area approximately equivalent to an area of a 05 m radius sphere. The capacitance represented by the human body and ground is of the order of 646 k 326 mj.
Simple Fast Method For Patient Body Capacitance And Power
Human body capacitance measurement. For all of the measurements reported here the sampling frequency was set to 500 hz. 22 in other words the circuit comprised of the. The human body capacitance to a far ground is 100 200 pf which is really a minimum value. Therefore the absolute capacitance of the human body is 6 using this value we can now create the human body model which serves as the basis for the esd testing in emc. It would be low when standing on top of a pole with nothing nearby but high when leaning against an insulated but grounded large metal. In the human body the human body capacitance hbc is traditionally chosen as 100 pf.
It is therefore not clear what factors govern the body capacitance. Measurements of the human body capacitance for a combination of polymeric soles and lino leum floor covering. As i always say ac hurts more than dc and the reason is human body capacitance. Body capacitance is the physical property of the human body that has it act as a capacitorlike any other electrically conductive object a human body can store electric charge if insulated. A standing human body insulated from ground by footwear andor floor covering is in principle an insulated conductor and has as such a capacitance ie. In this paper three types of polyhedra with 765 917 and 1529 surfaces are used.
I measured my resistance over dry skin to be close to 1m ohm. The actual amount of capacitance varies with the surroundings. The grounding resistance of the person was measured by a keitliley 620 electrometer. You can read my articles here. Lets see how big this capacitance is. The human body consists of polyhedra in the calculation.
Different skin conditions changes this resistance. Cbody and rbody are human body capacitance and resistance. And that frequency was chosen with the assumption that the frequencies contained in the current exchange would be very low dominated by the large time constant t 1rresistanceccapacitance imposed by the human subject capacitance and skin resistance. In this paper the static capacitance of a body standing on a ground plane is calculated by means of the surface charge method. These measurements could be valuable when considering the role that the human body. This correlates to an impedance of about 13 megohms at 60 hz which corresponds to a minimum of 9 ua at 120 vac to ground.
Rsource is the series resistance you put between supply and body. The ability to store a charge and possibly discharge the stored energy in a spark discharge. The capacitance of the body is 659 121 pf and the electro static voltage to which the body can be charged is 13 802 5 4443 v. If we modeled the body as a sphere of radius 1m its capacitance would equal 111 pf. It appears that there is a difference of 98 pf or about 58 oo of. You can measure the resistance using a multimeter.
Gallery of Human Body Capacitance Measurement
