Impacts to measurement uncertainty of radiated EMI measurement by setting terminating condition of AC mains cable leaving from test area

This paper verifies the degree of influence that the standardization of mains cable termination condition which is currently proposed with CISPR/SC-I gives to the Standards Compliance Uncertainty (SCU). First of all, we presumed the uncertainty value of the mains cable termination in the radiating emission measurement from the results of Round Robin Test which circulated the same EUT, the same cable termination device, and the same mains cable layout. And then, the radiating emission levels which were calculated considering with the tolerance of the termination impedance were used for presuming the measurement uncertainty when the mains cable was terminated by the device. Finally, the expanded Measurement Instrumentation Uncertainty (MIU) including the uncertainty by AC mains cable terminating condition was considered in calculation. From this result we have proposed this condition shall be included to the MIU.