Justification of Balanced VHF-LISN Termination

Mains cable termination of equipment for radiated emission testing is currently under discussion in CISPR/A-I Joint Ad-hoc Group-6 (JAHG-6), with both balanced and unbalanced Very High Frequency Line Impedance Stabilization Networks (VHF-LISN) being proposed for standardization. Based on the results of Round Robin Testing (RRT), this paper discusses the justification for using the balanced VHF-LISN for the power cable of Equipment Under Test (EUT). The paper concludes that a balanced VHF-LISN is suitable for the current radiated emission test of the enclosure port of EUT, and where consideration of emission from an unbalanced power supply network is necessary, an unbalanced VHF-LISN is effective.