Contribution of Impedance Imperfection of the T-type ISNs in Measurement Uncertainty of Conducted Disturbances

Method of uncertainty estimation due to impedance imperfection of the T-type impedanced stabilisation networks (ISNs) is presented. Elaboration is performed for two cases: for measured common mode impedance of the ISN and for assumption of tolerances imposed on this impedance. Estimation is illustrated with uncertainty calculation for the ISN designed for one pair of symmetrical, unshielded lines, so called T2 ISN. There is only one publication, namely [7] in which this uncertainty is mentioned. Numbers cited in this document are underestimated compared with what is presented in this paper.