Electromagnetic Interference from Electric Arcs in the Frequency Range 0.1-1000 MHz

The electromagnetic interference (EMI) from various forms of electrical discharges was investigated, and the measured levels were compared with civilian and military statutory limits of interference. The more stable arc forms, such as moderate-current (50-250A) arcs in argon flow, gave low levels of EMI conforming with all statutory limits throughout the frequency spectrum (0.1-1000 MHz). The interference from high-frequency/high-voltage spark discharges, used for arc initiation, was found to exceed statutory limits if used on a continuous basis.