EN IEC 60939-3:2024

Passive filter units for electromagnetic interference suppression - Part 3: Passive filter units for which safety tests are appropriate

IEC 60939-3:2024 is available as IEC 60939-3:2024 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.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.

Passive Filter für die Unterdrückung von elektromagnetischen Störungen - Teil 3: Filter, für die Sicherheitsprüfungen vorgeschrieben sind

Filtres passifs d'antiparasitage - Partie 3: Filtres passifs pour lesquels des essais de sécurité sont appropriés

IEC 60939-3:2024 est disponible sous forme de IEC 60939-3:2024 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.L’IEC 60939-3:2024 couvre les filtres passifs utilisés pour atténuer les signaux aux fréquences radioélectriques indésirables (par exemple, le bruit ou le brouillage) générés par des sources électromagnétiques. Les filtres à voie unique et à voies multiples à l’intérieur d’une enveloppe, ou montés sur une carte de circuit imprimé qui forme une entité compacte, font partie du domaine d’application du présent document. Les filtres constitués d’éléments capacitifs dans lesquels l’inductance est inhérente à la construction du filtre font partie du domaine d’application du présent document. De même, les filtres constitués d’éléments inductifs dans lesquels la capacité est inhérente à la construction du filtre font également partie du domaine d’application du présent document. Il appartient au fabricant d’indiquer si un composant donné doit être conçu comme un condensateur, une inductance ou un filtre. Les filtres peuvent également inclure d’autres composants tels que des résistances et/ou des varistances ou des composants similaires. Le présent document s’applique aux filtres passifs d’antiparasitage pour lesquels des essais de sécurité sont appropriés. Ceci implique que les filtres spécifiés selon le présent document sont soit connectés à des réseaux d’alimentation (lorsque la conformité aux essais obligatoires du Tableau B.1 est nécessaire), soit utilisés dans d’autres positions de circuit dans lesquelles la spécification de l’équipement précise que certains ou tous ces essais de sécurité sont exigés. Le présent document s’applique à des filtres passifs qui sont connectés à un réseau d’alimentation en courant alternatif ou à une autre alimentation (en courant continu ou en courant alternatif) dont la tension nominale ne dépasse pas 1 000 V en courant alternatif et dont la fréquence nominale ne dépasse pas 400 Hz, ou dont la tension nominale ne dépasse pas 1 500 V en courant continu. NOTE Pour les applications en courant alternatif, l’IEC 60384-14 s’applique aux condensateurs qui sont connectés au réseau d’alimentation en courant alternatif dont la fréquence nominale ne dépasse pas 100 Hz. Le présent document couvre les filtres d’appareil, mais ne couvre pas les filtres d’installation, les filtres connectés par cordon, ni les filtres enfichables directement. Ces autres filtres seront couverts par une autre spécification intermédiaire. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente: a) des articles ont été séparés pour les essais de sécurité et de performances; b) une note est ajoutée en ce qui concerne l’utilisation de plusieurs condensateurs de classe X qui relient en pont une isolation principale dans les filtres triphasés; c) des caractéristiques et conditions de remplacement des condensateurs de classe X et de classe Y sont maintenant décrites dans un paragraphe 4.1 différent; d) des tableaux de lignes de fuite et de distances d’isolement sont mis à jour et sont conformes aux dernières éditions de l’IEC 60938-2 et de l’IEC 60664-1; e) le mesurage de la tension pour les mesurages de l’inductance est admis (7.3); f) des exigences sont ajoutées pour le marquage selon l’énergie restante après la déconnexion; g) le contenu de CTL DSH 2044:2016 est ajouté pour l’essai de température des filtres IEC; h) une

Pasivni filtri za dušenje elektromagnetnega motenja - 3. del: Enote pasivnih filtrov, za katere varnostni preskusi ustrezajo (IEC 60939-3:2024)

Ta del standarda IEC 60939 zajema pasivne filtre za slabenje neželenih radiofrekvenčnih signalov (kot so šum ali motnje), ki jih ustvarijo elektromagnetni viri.
Ta dokument obravnava tako enokanalne kot tudi večkanalne filtre v enem ohišju ali filtre, nameščene na tiskanem vezju, ki tvorijo kompaktno entiteto.
Področje uporabe tega dokumenta zajema filtre, izdelane iz kapacitivnih elementov, pri katerih zgradba filtra zagotavlja induktivnost. Zajeti so tudi filtri, izdelani iz induktivnih elementov, pri katerih zgradba filtra zagotavlja kapacitivnost. Proizvajalec se sam odloči, ali želi dano komponento označiti kot kondenzator, induktor ali filter. V filtre je mogoče vključiti tudi druge komponente, kot so upori in/ali varistorji ali podobne komponente.
Ta dokument se uporablja za enote pasivnih filtrov za dušenje elektromagnetnega motenja, za katere varnostni preskusi ustrezajo. To pomeni, da se filtri, določeni v skladu s tem dokumentom, priključijo na omrežno napajanje, kadar je zahtevana skladnost z obveznimi preskusi iz preglednice B.1, ali se uporabijo na drugih mestih v tokokrogu, za katera je v specifikaciji opreme določeno, da so zahtevani nekateri ali vsi ti varnostni preskusi.
Ta dokument se uporablja za enote pasivnih filtrov, ki bodo priključene v izmenično napajalno omrežje ali drug vir napajanja (enosmerni ali izmenični) z nazivno izmenično napetostjo do 1000 V z nazivno frekvenco največ 400 Hz oziroma z enosmerno napetostjo 1500 V.
OPOMBA: Pri uporabi z izmenično napetostjo se standard IEC 60384-14 uporablja za kondenzatorje, ki se priključijo na izmenično omrežno napajanje z nazivno frekvenco največ 100 Hz.
Ta dokument zajema filtre za naprave (US), vendar ne zajema filtrov za sisteme, filtrov, priključenih s kablom, ali filtrov za neposredno priključitev. Ti filtri bodo obravnavani v drugi področni specifikaciji.

General Information

• Status: Published
• Publication Date: 21-Mar-2024
• ICS: 31.160 - Electric filters
• Technical Committee: CLC/TC 40XA - CLC/TC 40XA
• Drafting Committee: IEC/TC 40 - IEC_TC_40
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 22-Mar-2024
• Due Date: 31-Jan-2024
• Completion Date: 22-Mar-2024
• Ref Project: SIST EN IEC 60939-3:2024 - Passive filter units for electromagnetic interference suppression - Part 3: Passive filter units for which safety tests are appropriate (IEC 60939-3:2024)

Relations

• Replaces: EN 60939-3:2015/AC:2016-04 - Passive filter units for electromagnetic interference suppression - Part 3: Passive filter units for which safety tests are appropriate
• Effective Date: 10-May-2022
• Replaces: EN 60939-3:2015/AC:2018-08 - Passive filter units for electromagnetic interference suppression - Part 3: Passive filter units for which safety tests are appropriate
• Effective Date: 10-May-2022
• Replaces: EN 60939-3:2015 - Passive filter units for electromagnetic interference suppression - Part 3: Passive filter units for which safety tests are appropriate
• Effective Date: 10-May-2022

Overview

EN IEC 60939-3:2024 - Passive filter units for electromagnetic interference suppression (Part 3) - defines safety-related requirements and test procedures for passive EMI filter units for which safety tests are appropriate. The standard applies to single- and multi-channel passive filters housed in an enclosure or implemented on a printed circuit board (compact entities) that will be connected to AC or DC supplies with nominal voltages up to 1 000 V AC (≤ 400 Hz) or 1 500 V DC. It covers filters used to attenuate unwanted radio‑frequency signals (noise/interference) and is intended for filter types requiring mandatory safety testing (for example, those connected to the mains). EN IEC 60939-3:2024 is the 2024 edition (RLV with redline) and documents technical changes from the previous edition.

Key topics and technical requirements

• Scope and classification: Defines which passive filter units are within scope (excludes facility filters, cord‑connected filters and direct plug‑in filters; includes appliance filters).
• Safety vs performance tests: Separate clauses for safety tests and performance tests, and a structured test plan (sampling, groupings, requalification).
• Component rules: Requirements for use and substitution of Class X and Class Y capacitors, and updated guidance on multiple X capacitors in 3‑phase filters.
• Insulation & clearances: Updated creepage and clearance tables aligned with IEC 60938-2 and IEC 60664-1.
• Electrical measurements: Procedures for inductance, capacitance, insulation resistance, voltage proof, and insertion loss measurements (including allowance for voltage measurement in inductance tests).
• Thermal & mechanical tests: Temperature testing, temperature-rise requirements for specimens, and vibration/environmental conditions per related IEC environmental tests.
• Marking and packaging: Marking requirements including information related to remaining energy after disconnection, and packaging markings.
• Test sample preparation: Rules on potting and sample submission (e.g., movement of tests between groups; 1A samples submitted without potting).

Applications and who uses it

• EMC engineers designing EMI filter units for appliances, industrial equipment, or power electronics.
• Component and module manufacturers producing passive filters, chokes, and suppression networks.
• Product safety and compliance teams preparing documentation and samples for safety approvals and certification testing.
• Test laboratories and certification bodies performing mandated safety and performance tests.
• Procurement and design assurance teams requiring conformance evidence for suppliers.

Keywords: EN IEC 60939-3:2024, passive filter units, EMI filters, electromagnetic interference suppression, safety tests, X capacitors, Y capacitors, creepage and clearance.

Related standards

• IEC 60939‑1, IEC 60938‑1 / IEC 60938‑2 (inductors and sectional specs)
• IEC 60384‑14 (capacitors for EMI suppression)
• IEC 60664‑1 (insulation coordination)
• CISPR 17 (measurement methods for passive EMC filters)
• IEC environmental and fire test standards referenced in the normative annexes.

Standards Content (Sample)

SLOVENSKI STANDARD
01-junij-2024
Pasivni filtri za dušenje elektromagnetnega motenja - 3. del: Enote pasivnih filtrov,
za katere varnostni preskusi ustrezajo (IEC 60939-3:2024)
Passive filter units for electromagnetic interference suppression - Part 3: Passive filter
units for which safety tests are appropriate (IEC 60939-3:2024)
Passive Filter für die Unterdrückung von elektromagnetischen Störungen - Teil 3: Filter,
für die Sicherheitsprüfungen vorgeschrieben sind (IEC 60939-3:2024)
Filtres passifs d'antiparasitage - Partie 3: Filtres passifs pour lesquels des essais de
sécurité sont appropriés (IEC 60939-3:2024)
Ta slovenski standard je istoveten z: EN IEC 60939-3:2024
ICS:
31.160 Električni filtri Electric filters
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60939-3

NORME EUROPÉENNE
EUROPÄISCHE NORM March 2024
ICS 31.160 Supersedes EN 60939-3:2015;
EN 60939-3:2015/AC:2016-04;
EN 60939-3:2015/AC:2018-08
English Version
Passive filter units for electromagnetic interference suppression -
Part 3: Passive filter units for which safety tests are appropriate
(IEC 60939-3:2024)
Filtres passifs d'antiparasitage - Partie 3: Filtres passifs Passive Filter für die Unterdrückung von
pour lesquels des essais de sécurité sont appropriés elektromagnetischen Störungen - Teil 3: Filter, für die
(IEC 60939-3:2024) Sicherheitsprüfungen vorgeschrieben sind
(IEC 60939-3:2024)
This European Standard was approved by CENELEC on 2024-03-18. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60939-3:2024 E

European foreword
The text of document 40/3102/FDIS, future edition 2 of IEC 60939-3, prepared by IEC/TC 40
"Capacitors and resistors for electronic equipment" was submitted to the IEC-CENELEC parallel vote
and approved by CENELEC as EN IEC 60939-3:2024.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2024-12-18
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2027-03-18
document have to be withdrawn
This document supersedes EN 60939-3:2015 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 60939-3:2024 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60068-2-13 NOTE Approved as EN IEC 60068-2-13
IEC 60068-2-27 NOTE Approved as EN 60068-2-27
IEC 60085 NOTE Approved as EN 60085
IEC 60294 NOTE Approved as EN 60294
IEC 60335-1 NOTE Approved as EN IEC 60335-1
IEC 60384-9 NOTE Approved as EN 60384-9
IEC 60939-1 NOTE Approved as EN 60939-1
IEC 60947-1 NOTE Approved as EN IEC 60947-1
IEC 60990 NOTE Approved as EN 60990
IEC 61112 NOTE Approved as EN 61112
IEC 61140 NOTE Approved as EN 61140
IEC 62109-1 NOTE Approved as EN 62109-1
ISO 80000-1 NOTE Approved as EN ISO 80000-1
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60060-1 2010 High-voltage test techniques - Part 1: EN 60060-1 2010
General definitions and test requirements
IEC 60062 2016 Marking codes for resistors and capacitors EN 60062 2016
IEC 60068-1 2013 Environmental testing - Part 1: General EN 60068-1 2014
and guidance
IEC 60068-2-1 2007 Environmental testing - Part 2-1: Tests - EN 60068-2-1 2007
Test A: Cold
IEC 60068-2-2 2007 Environmental testing - Part 2-2: Tests - EN 60068-2-2 2007
Test B: Dry heat
IEC 60068-2-6 2007 Environmental testing - Part 2-6: Tests - EN 60068-2-6 2008
Test Fc: Vibration (sinusoidal)
IEC 60068-2-14 2023 Environmental testing - Part 2-14: Tests - EN IEC 60068-2-14 2023
Test N: Change of temperature
IEC 60068-2-17 2023 Environmental testing - Part 2-17: Tests - EN IEC 60068-2-17 2023
Test Q: Sealing
IEC 60068-2-20 2021 Environmental testing - Part 2-20: Tests - EN IEC 60068-2-20 2021
Test Ta and Tb: Test methods for
solderability and resistance to soldering
heat of devices with leads
IEC 60068-2-21 2021 Environmental testing - Part 2-21: Tests - EN IEC 60068-2-21 2021
Test U: Robustness of terminations and
integral mounting devices
IEC 60068-2-30 2005 Environmental testing - Part 2-30: Tests - EN 60068-2-30 2005
Test Db: Damp heat, cyclic (12 h + 12 h
cycle)
IEC 60068-2-45 1980 Basic environmental testing procedures - EN 60068-2-45 1992
Part 2-45: Tests - Test XA and guidance:
Immersion in cleaning solvents
IEC 60068-2-78 2012 Environmental testing - Part 2-78: Tests - EN 60068-2-78 2013
Test Cab: Damp heat, steady state
IEC 60384-14 2023 Fixed capacitors for use in electronic EN IEC 60384-14 2023
equipment - Part 14: Sectional
specification - Fixed capacitors for
electromagnetic interference suppression
and connection to the supply mains
IEC 60664-1 2020 Insulation coordination for equipment EN IEC 60664-1 2020
within low-voltage supply systems - Part 1:
Principles, requirements and tests
IEC 60695-11-5 2016 Fire hazard testing - Part 11-5: Test flames EN 60695-11-5 2017
- Needle-flame test method - Apparatus,
confirmatory test arrangement and
guidance
IEC 60695-11-10 2013 Fire hazard testing - Part 11-10: Test EN 60695-11-10 2013
flames - 50 W horizontal and vertical flame
test methods
IEC 60938-1 2021 Fixed inductors for electromagnetic EN IEC 60938-1 2021
interference suppression - Part 1: Generic
specification
IEC 60938-2 2021 Fixed inductors for electromagnetic EN IEC 60938-2 2021
interference suppression - Part 2: Sectional
specification on power line chokes
IEC 60940 2015 Guidance information on the application of EN 60940 2015
capacitors, resistors, inductors and
complete filter units for electromagnetic
interference suppression
CISPR 17 2011 Methods of measurement of the EN 55017 2011
suppression characteristics of passive
EMC filtering devices
IEC 60939-3 ®
Edition 2.0 2024-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Passive filter units for electromagnetic interference suppression –

Part 3: Passive filter units for which safety tests are appropriate

Filtres passifs d'antiparasitage –

Partie 3: Filtres passifs pour lesquels des essais de sécurité sont appropriés

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.160  ISBN 978-2-8322-8175-8

– 2 – IEC 60939-3:2024 © IEC 2024
CONTENTS
FOREWORD . 8
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 12
4 General requirements . 16
4.1 Classification and usage of class X and Y capacitors . 16
4.1.1 General . 16
4.1.2 Class X capacitors . 16
4.1.3 Class Y capacitors . 16
4.2 Information to be given in a detail specification . 17
4.2.1 General . 17
4.2.2 Outline drawing and dimensions . 18
4.2.3 Mounting . 18
4.2.4 Ratings and characteristics . 18
4.3 Marking . 19
4.3.1 General . 19
4.3.2 Coding . 19
4.3.3 Marking details . 19
4.3.4 Marking of filters . 19
4.3.5 Marking of packaging . 19
4.3.6 Additional marking . 19
4.4 Components . 20
4.5 Overcurrent protective devices . 20
4.6 Wiring and Insulation . 20
4.6.1 General . 20
4.6.2 Sleeving, tubing and wire insulation . 20
4.6.3 Properties of insulation material. 20
4.7 Protective Bonding Conductors . 21
4.8 Corrosion . 21
5 Preferred ratings and characteristics . 21
5.1 Preferred characteristics . 21
5.1.1 General . 21
5.1.2 Preferred climatic categories . 21
5.2 Preferred values of ratings . 22
5.2.1 Rated voltage (U ) . 22
R
5.2.2 Rated temperature . 22
5.2.3 Passive flammability . 22
6 Test plan for safety tests . 22
6.1 Structurally similar filters . 22
6.2 Safety approval procedure . 23
6.2.1 General . 23
6.2.2 Sampling . 23
6.2.3 Tests . 23
6.3 Requalification tests. 24
7 Test and measurement procedures . 24
7.1 Measurement conditions . 24

IEC 60939-3:2024 © IEC 2024 – 3 –
7.1.1 General . 24
7.1.2 Standard atmospheric conditions for testing . 24
7.1.3 Recovery conditions . 25
7.1.4 Referee conditions . 25
7.1.5 Reference conditions . 25
7.1.6 Drying . 25
7.2 Visual examination and check of dimensions . 26
7.2.1 Visual examination . 26
7.2.2 Dimensions (gauging) . 26
7.2.3 Dimensions (detail) . 26
7.2.4 Creepage distances and clearances . 26
7.3 Inductance measurement . 29
7.3.1 General . 29
7.3.2 Measuring conditions . 29
7.4 Earth inductors incorporated in filters . 29
7.5 Capacitance . 29
7.5.1 General . 29
7.5.2 Measuring conditions . 29
7.6 Insertion loss . 30
7.7 Insulation resistance . 30
7.7.1 General . 30
7.7.2 Measuring voltage . 30
7.7.3 Application of measuring voltage . 31
7.7.4 Mean time to measuring . 32
7.7.5 Temperature correction factor . 32
7.7.6 Information to be given in a detail specification . 32
7.7.7 Requirements . 34
7.8 Voltage proof . 35
7.8.1 General . 35
7.8.2 Test procedure . 35
7.8.3 Applied voltage . 35
7.8.4 Tests . 36
7.8.5 Requirements . 37
7.8.6 Repetition of the voltage proof test . 37
7.8.7 Information to be given in a detail specification . 37
7.8.8 Requirements . 37
7.9 DC line resistance or voltage drop at rated current . 37
7.9.1 General . 37
7.9.2 DC line resistance . 38
7.9.3 Voltage drop at rated current . 38
7.10 Discharge resistance . 38
7.10.1 General . 38
7.10.2 Resistor Test . 38
7.11 Capacitor discharge . 39
7.11.1 General . 39
7.11.2 Discharge measurement . 39
7.12 Robustness of terminations . 39
7.12.1 General . 39
7.12.2 Test Ua1 – Tensile . 39

– 4 – IEC 60939-3:2024 © IEC 2024
7.12.3 Test Ub – Bending . 40
7.12.4 Test Uc – Torsion . 40
7.12.5 Test Ud – Torque . 40
7.12.6 Visual examination . 41
7.13 Resistance to soldering heat . 41
7.13.1 Applicability of the test. 41
7.13.2 Pre-measurement . 41
7.13.3 Test conditions . 41
7.13.4 Test severity . 42
7.13.5 Intermediate inspection, measurements and requirements . 42
7.14 Climatic sequence. 42
7.14.1 General . 42
7.14.2 Initial measurements . 42
7.14.3 Dry heat . 42
7.14.4 Damp heat, cyclic . 42
7.14.5 Cold. 43
7.14.6 Low air pressure . 43
7.14.7 Damp heat, cyclic, remaining cycles . 43
7.14.8 Final inspection, measurements and requirements. 43
7.15 Damp heat, steady state . 44
7.15.1 Pre-measurements . 44
7.15.2 Test method . 44
7.15.3 Test conditions . 44
7.15.4 Final inspection, measurements and requirements. 44
7.16 Temperature rise . 44
7.16.1 General . 44
7.16.2 Test method . 45
7.16.3 Test description . 45
7.16.4 Requirements . 46
7.17 Current overload . 47
7.17.1 Pre-measurements . 47
7.17.2 Test method . 47
7.17.3 Final inspection, measurements and requirements. 48
7.18 Leakage current . 48
7.19 Protective conductor resistance . 48
7.20 Impulse voltage. 48
7.20.1 General . 48
7.20.2 Initial measurements . 48
7.20.3 Test conditions . 48
7.20.4 Requirements . 49
7.21 Endurance . 49
7.21.1 General . 49
7.21.2 General test conditions . 49
7.21.3 Test conditions – current test . 50
7.21.4 Test conditions – voltage test, terminations/case . 50
7.21.5 Test conditions – voltage test between terminations . 51
7.21.6 Test conditions – combined voltage/current tests . 51
7.21.7 Final inspection, measurements and requirements. 51
7.22 Passive flammability . 52

IEC 60939-3:2024 © IEC 2024 – 5 –
7.22.1 General . 52
7.22.2 Test method . 52
7.23 Active flammability . 53
7.24 Solvent resistance of the marking . 53
7.24.1 General . 53
7.24.2 Test description . 53
7.24.3 Requirements after test . 53
8 Optional tests (for performance only) . 53
8.1 Solderability . 53
8.1.1 General . 53
8.1.2 Test method . 53
8.1.3 Test conditions . 53
8.1.4 Requirements . 54
8.1.5 Final measurements and requirements . 54
8.2 Rapid change of temperature . 54
8.2.1 Pre-measurements . 54
8.2.2 Test method . 54
8.2.3 Final inspection . 55
8.3 Vibration . 55
8.3.1 Pre-measurements . 55
8.3.2 Test method . 55
8.3.3 Test conditions . 55
8.3.4 Intermediate inspection . 55
8.3.5 Final Inspection . 55
8.4 Shock . 55
8.4.1 Pre-measurements . 55
8.4.2 Test method . 55
8.4.3 Test conditions . 55
8.4.4 Final Inspection . 56
8.5 Container sealing . 56
8.5.1 General . 56
8.5.2 Test conditions . 56
8.5.3 Requirements . 56
8.6 Charge and discharge . 56
8.6.1 General . 56
8.6.2 Test circuits and wave forms . 56
8.6.3 Information given in detail specification . 58
8.6.4 Initial measurements . 58
8.6.5 Test conditions . 59
8.6.6 Final measurements and requirements . 59
8.7 Component solvent resistance . 59
8.7.1 General . 59
8.7.2 Initial measurements . 59
8.7.3 Test description . 60
8.7.4 Final measurements . 60
Annex A (informative) Calculation of leakage current . 61
A.1 General . 61
A.2 Calculation of leakage current for 1-line filters . 61
A.3 Calculation of leakage current for 2-line filters . 62

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A.4 Calculation of leakage current for 3-line filters . 62
A.5 Calculation of leakage current for 4-line filters . 64
Annex B (normative) Sampling plan for safety requirements only . 65
Annex C (normative) Test schedule for safety requirements only . 67
Annex D (normative) Circuit for the impulse voltage test . 70
Annex E (normative) Circuit for the endurance test . 72
Annex F (normative) Declaration of design. 73
Annex G (informative) Safety and performance tests qualification approval –
Assessment level DZ . 74
Annex X (informative) Cross reference for references to the previous edition of this
document . 76
Bibliography . 79

Figure 1 – Asymmetrical and symmetrical test circuit . 15
Figure 2 – Examples for the application of Tests A and B of Table 7 . 33
Figure 3 – Examples for the application of Test C of Table 7. 34
Figure 4 – Impulse wave form . 49
Figure 5 – Relay circuit . 56
Figure 6 – Thyristor circuit . 57
Figure 7 – Voltage and current waveforms . 58
Figure A.1 – Leakage current for 1-line filters . 61
Figure A.2 – Leakage current for 2-line filters . 62
Figure A.3 – Leakage current for 3-line filters . 63
Figure A.4 – Leakage current for 4-line filters . 64
Figure D.1 – Impulse voltage test circuit . 70
Figure E.1 – Endurance test circuit . 72

Table 1 – Classification of Class X capacitors . 16
Table 2 – Classification of Class Y capacitors . 17
Table 3 – Standard atmospheric conditions . 25
Table 4 – Creepage distances . 28
Table 5 – Clearance. 28
Table 6 – DC voltage for insulation resistance . 31
Table 7 – Measuring points . 33
Table 8 – Insulation resistance – Safety tests only . 34
Table 9 – Insulation resistance – Safety and performance tests . 35
Table 10 – Voltage proof (filter connected to mains) . 36
Table 11 – Voltage proof (filter not connected to mains; e.g. DC filters) . 36
Table 12 – Force for wire terminations . 40
Table 13 – Torque . 40
Table 14 – Number of cycles . 43
Table 15 – Maximum temperatures . 47
Table 16 – Categories of flammability . 52
Table 17 – Preferred severity . 56

IEC 60939-3:2024 © IEC 2024 – 7 –
Table 18 – Measurements and requirements after charge and discharge . 59
Table B.1 – Tests concerning safety requirements only . 65
Table B.2 – Lot-by-lot test – Safety tests only approval . 66
Table C.1 – Test schedule for safety requirements only . 67
Table D.1 – Values of C , C , R , R , C . 70
X T P S P
Table D.2 – Values and tolerances of C , t , t . 71
x r d
Table G.1 – Sampling plan – Assessment level DZ . 74
Table X.1 – Reference to IEC 60939-3 for clause/subclause or annex . 76
Table X.2 – Reference to IEC 60939-3 for Figures/Tables. 78

– 8 – IEC 60939-3:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PASSIVE FILTER UNITS FOR ELECTROMAGNETIC
INTERFERENCE SUPPRESSION –
Part 3: Passive filter units for which safety tests are appropriate

FOREWORD
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
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IEC 60939-3 has been prepared by of IEC technical committee 40: Capacitors and resistors for
electronic equipment. It is an International Standard.
This second edition cancels and replaces the first edition published in 2015,
Corrigendum 1:2016 and Corrigendum 2:2018. This edition constitutes a technical revision.
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;
IEC 60939-3:2024 © IEC 2024 – 9 –
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) A
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