Quantitative Analysis of Operator Influence on IEC 61000-4-2 Indirect ESD Testing and Recommendations for Enhanced Reproducibility

The reproducibility of system-level electrostatic discharge (ESD) testing per IEC 61000-4-2 remains challenged by waveform variability, notably in the second peak region, partly due to human operator influence. Although recent Standard revisions introduce parameters like I<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P2</sub>, operator effects during indirect discharges are still unaddressed. This study examines human presence impacts on ESD waveforms during indirect discharges to horizontal and vertical coupling planes, using a SpaceWire link as the device under test. Injected and shield currents were measured under various operator conditions, alongside tests in operator-free setups with different grounding cable arrangements and protective bodywear. Results confirm significant operator-induced waveform alterations. While operator-free setups reduce variability, grounding cable layout remains crucial. Standardized, operator-free configurations with defined grounding are recommended. Where manual operation is unavoidable, ESD gloves and shoes partially improve test consistency.