1 Scope
This part of IEC 60939
covers passive filters used to attenuate unwanted radio-frequency signals (such as
noise or interference) generated from electromagnetic sources.
Both single and multi-channel filters within one enclosure or which are built on a
printed circuit board forming a compact entity are included within the scope of this
document.
Filters constructed of capacitive elements where the inductance is inherent in the
construction of the filter are within the scope of this document. Similarly, filters
constructed of inductive elements where the capacitance is inherent in the construction
of the filter are also within the scope of this document. It is up to the manufacturer
to state whether a given component is to be designed as a capacitor, an inductor or
a filter. Filters can include also other components such as resistors and/or varistors
or similar components.
This document applies to passive filter units for electromagnetic interference suppression
for which safety tests are appropriate. This implies that filters specified according
to this document will either be connected to mains supplies, when compliance with
the mandatory tests of Table B.1 is necessary, or used in other circuit positions where the equipment specification
specifies that some or all of these safety tests are required.
This document applies to passive filter units, which will be connected to an AC mains
or other supply (DC or AC) with a nominal voltage not exceeding 1 000 V AC, with a
nominal frequency not exceeding 400 Hz, or 1 500 V DC.
物联产品&设备电磁兼容参考设计思路（二）