Standard

IEC 60939-3:2024 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. 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. Note: For AC use, IEC 60384-14 applies to capacitors which will be connected to AC mains with a nominal frequency not exceeding 100 Hz. This document covers appliance filters (US) but does not cover facility filters, cord-connected filters or direct plug-in filters. These other filters will be covered by another sectional specification.
This edition includes the following significant technical changes with respect to the previous edition:
a) separated clauses for safety and performance tests;
b) added note for use of multiple X capacitors bridging basic insulation in 3 phase filters;
c) characteristics and conditions to substitute X and Y capacitors are now described in a separate Subclause 4.1;
d) creepage and clearance tables updated and in line with the latest editions of IEC 60938-2 and IEC 60664-1;
e) allowing voltage measurement for inductance measurements (7.3);
f) added requirements for marking depending on remaining energy after disconnection;
g) added content of CTL DSH 2044:2016 for temperature test of IEC filters;
h) added note about temperature rise required specimens for safety testing;
i) changed index of capacitors in Annex A to avoid confusion between index name and capacitor class;
j) moved tests from group 1A to 2. Now, samples in group 1A need to be submitted without potting;
k) revision of all parts of the document has taken place based on the ISO/IEC Directives, Part 2:2021, and harmonization with other similar kinds of documents. Annex X contains all cross-references of changes in clause/subclause numbers.