Time domain measurement of magnetic field radiated by electrostatic discharge for electromagnetic pollution assessment

The main goal of this paper is the analysis of the properties of the magnetic field wave properties according to distance from discharge point in order to obtain a quantification of electromagnetic pollution in surroundings of the studied equipment. The measurements are performed with the field probe in the vicinity of the ESD (electrostatic discharge) event, oriented parallel to the discharge plane to ensure maximum coupling, in order to assess the time domain measurement of magnetic field. The radiated magnetic field associated with the discharge can be determined from the discharge current or from the induced voltage in the field probe, based on Faraday´s law. Magnetic field will be evaluated after multiple contact discharges in different points. The waveforms of magnetic fields are different depending on the ESD generator construction. In the paper we present the influence of two factors upon magnetic field wave above horizontal coupling plane: distance from discharge point and size of ground strap.