Reducing compliance uncertainty with AMN measurements

In IEC CISPR 16-4-2 [1, 2] tight impedance requirements are given for artificial mains networks (AMN). Unfortunately, these tight requirements will support measurement uncertainty but still not guarantee low compliance uncertainty if the whole test set-up, up to the port of the equipment being tested, is not taken into account. In this paper the impact of the design of the AMN as well as the mains cable used is evaluated. Incorrect cascading of typical AMN elements: impedance stabilizing network, attenuator(s), high-pass filters and impulse limiter results in erroneous findings which affect measurement uncertainty. Introduction of impedance requirements on the mains cable used enhances the compliance uncertainty by 20 dB, which is demonstrated by simulations and measurements.