However the body capacitance is strongly dependent on the relationship between the ground plane and the body posture. Formula to calculate capacitance using measured delay.
On The Human Body Communications Wake Up Receiver Design And
Human body capacitance measurement. Biological coherence and response to external stimuli new york city 1968 springer verlag. The person is subsequently connected in parallel to an external capacitor of known capacitance. Cbody and rbody are human body capacitance and resistance. Hence the static capacitance of the human body which is deeply related to the human body potential has been measured. Light emission from the human body complement med res 316 1989. 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.
The human body capacitance to a far ground is 100 200 pf which is really a minimum value. Capacitance of a human body in normal surroundings is typically in the tens to low hundreds of picofarads which is small by typical electronic standards. 00 0 00 bb bb b sf a f ac qq x x x uq cc εε εsx x x x s. Available measuring te chniques are based on measuring a frequency or duty cycle which is changed by the introduction of additional. Is there a enhanced human body model beyond the simple one consisting of a resistor and a capacitance to earth that can explain what i am seeing. Edwards r et al.
One of the main causes of this esd is known to be charging of the human body. I then measure the current going to that plate to estimate the capacitance from a human finger touch. The funny thing is that when i touch it the first reading is higher than the subsequent ones. On the other hand the electric capacitance of the human body c b during walking motion can be expressed as follows. Edwards r et al. Measurements of human bioluminescence acupuncture and electrotherapeutics res int j 1585 1990.
Measuring human body capacitance using series resistor. 3 therefore the electric potential of the human body u b during the motion of walking can be expressed as follows. This is enough to be sensed and used for capacitively operated light dimmers. Now as you saw in the video probing both vin and vout you can measure the delay and calculate the capacitance using the following formula. While humans are much larger than typical electronic components they are also mostly separated by significant distance from other conductive objects. Changes produced by human body movement in proximity.
Charge a person of unkown capacitance to 1000 volts. Determine the capacitance of the human body as follows. 1 11 cc c b sf x.
Gallery of Human Body Capacitance Measurement
