CISPR 17:2011

EMC filter providing reliable power supply

EMC filters and components are utilized for suppressing electromagnetic disturbances, and their effectiveness in this regard is measured by their suppression characteristics. The suppression characteristics depend on numerous factors, such as the impedance of the circuits to which they connect, operating voltage and current, and ambient temperature. The suppression characteristics of EMC filters are measured by using standardized measurement methods.  

The CISPR 17 is a technical standard for passive EMC filtering devices. This technical document specifies methods of measurement of the suppression characteristics of Passive EMC filtering devices. It applies to EMC filtering devices used in power, signal lines, and other circuits. The content of this document describes measurement methods, test setup, and other related details to measure the radio interference suppression characteristics of passive EMC filtering devices. Currently, the second edition of this standard (CISPR 17:2011, published in 2011) is available and valid.

The measurement methods described in the CISPR 17:2011 standard may also be applicable to combinations of EMC filtering devices and over-voltage protection devices. The frequency range covered by this standard is from 9KHz to several GHz depending on the device and test circuit. This standard describes measurement methods for laboratory tests (type tests) as well as factory tests.  The measurement methods covered in the standard are useful to compare EMI suppression devices among each other and allow an efficient selection of appropriate EMI suppressor devices.

The CISPR 17 provides measurement procedures for unbiased and biased conditions.  The measurements carried out under bias conditions are helpful/useful to find out the potential non-linear behavior of EMC filtering devices, such as saturation effects in inductors with magnetic cores.  Also,  if the non-linear behavior can be determined by other methods (e.g., separate saturation measurement of the inductors used), the measurement under the bias conditions may be omitted.

This second edition (CISPR 17:2011) supersedes the first edition published in 1981. The first edition described the insertion loss measurement methods specifically for power-line filters. Nowadays, electronic devices incorporate a wide variety of advanced EMC filters and suppression components to effectively suppress electromagnetic disturbances. Standardized measurement methods need to be used to characterize those filters. The second edition of CISPR 17 includes new methods for the measurement of impedance and S-parameters for such EMI devices.

Additional information of CISPR 17: 2011: