The switching frequencies of switching power supplies start at approx. 25 kHz and extend to MHz range. In frequency converters clock frequencies of about 4 kHz to 32 kHz are achieved. Due to rectangular or pulse waveform, all harmonics have an influence on the interference spectrum additionally.
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The Institute of Safety of Work (IFA) has already measured magnetic fields in the range of over 100 A / m in complex large-scale installations, directly in front of open switch cabinets. These interference magnetic fields can induce interference voltages in the range of 500 mVSS to a few VSS in signal lines, bus lines or printed circuit boards.
The guideline "Non-ionizing Radiation" of electromagnetic fields of the Association for Radiation Protection e.V. [1] and the BMAS Research Report 451 [2] reports were composed in detail on the effects of magnetic fields on humans.
In the vicinity of charging coils, the electric and magnetic fields are very high, not in phase and very inhomogeneous. The eddy currents induced by magnetic fields cause in the human body different body currents , resulting from potential differences. Depending on the frequency and level, this can irritate the nerve and muscle cells or increase the temperature in tissue and organs. Negative effects on the human body, however, are being discussed still controversially.
In the field of simulation of electromagnetic fields related to humans, it is assumed that a magnetic field in the body can cause stronger blood flow, which in turn could be responsible for an increase in temperature. Consideration must be given to effects on passive implants - warming, tissue heating - as well as on active implants - malfunctions, failures
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