SIST EN IEC 61000-4-29:2026
(Main)Electromagnetic compatibility (EMC) - Part 4-29: Testing and measurement techniques - Voltage dips, short interruptions and voltage variations on d.c. input power port immunity tests
- Abstract
This part of IEC 61000 defines test methods for immunity to voltage dips, short interruptions and voltage variations at the DC input power port of electrical or electronic equipment.
This document is applicable to equipment and systems whose DC input power ports are intended to be connected to low voltage DC networks external to the equipment and systems.
The object of this document is to establish a common and reproducible basis for testing electrical and electronic equipment when subjected to voltage dips, short interruptions or
voltage variations on DC input power ports.
This document defines:
– the range of test levels;
– the test generator;
– the test set-up;
– the test procedure.
The test described hereinafter applies to electrical and electronic equipment and systems. It also applies to modules or subsystems whenever the equipment under test’s (EUT) rated power is greater than the test generator capacity specified in Clause 6.
The ripple at the DC input power port is not included in the scope of this document. It is covered by IEC 61000-4-17.
This document does not specify the tests to be applied to particular apparatus or systems. Its main aim is to give a general basic reference to IEC product committees. These product committees (or users and manufacturers of equipment) remain responsible for the appropriate choice of the tests and the severity level to be applied to their equipment.
- Status
- Published
- Public Enquiry End Date
- 09-Apr-2026
- Publication Date
- 08-Nov-2026
- Technical Committee
- EMC - Electromagnetic compatibility
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 17-Sep-2026
- Due Date
- 22-Nov-2026
- Completion Date
- 09-Nov-2026
SIST EN IEC 61000-4-29:2026 is the SIST adoption of IEC 61000-4-29 for electromagnetic compatibility (EMC) immunity testing at a d.c. input power port. It specifies how to test electrical and electronic equipment and systems for voltage dips, short interruptions, and voltage variations on d.c. input power ports. Engineers, test laboratories, product committees, and manufacturers use it to choose test levels, configure the generator, run reproducible tests, and record the results.
What does SIST EN IEC 61000-4-29:2026 specify?
SIST EN IEC 61000-4-29:2026 defines a common test method for immunity of equipment connected to low-voltage DC networks external to the equipment. It covers the test levels, the test generator, the test set-up, and the test procedure.
The document is organized into these main clauses: Scope, Normative references, Terms and definitions, General, Test levels, Test generator, Test set-up, Test procedure, Evaluation of test results, and Test report. It also includes three annexes that add examples, a normative measurement method, and background on the DC network.
It excludes ripple on the DC input power port, which is covered by IEC 61000-4-17. It also notes that transient overvoltages caused by faults in the DC distribution system are outside its coverage. The document is a basic reference for product committees, which still decide which tests and severity levels suit their equipment.
| Annex | What it covers |
|---|---|
| Annex A | Informative examples of test generators and test set-up |
| Annex B | Normative inrush current measurement, including generator drive capability and EUT peak inrush current |
| Annex C | Informative description of the DC network |
What are the key requirements of SIST EN IEC 61000-4-29:2026?
SIST EN IEC 61000-4-29:2026 is built around a few practical choices that matter in the lab: which rated voltage to use, which disturbance levels to apply, how the generator must behave, and how to judge and report the result.
Reference voltage and test levels
- Clause 5 uses the equipment rated voltage (U_T) as the reference for test levels.
- If the EUT has a rated voltage range, the document gives a rule for when one voltage can be used and when both ends of the range shall be tested.
- Tables 1 to 3 give preferred levels and durations for voltage dips, short interruptions, and voltage variations.
- Product standards may choose one or more values from those tables, and the document notes that the shortest duration should be tested.
In practice, this means the user does not invent a disturbance profile from scratch. The product standard or test plan selects the relevant severities from the preferred set, so the same equipment can be tested consistently in different labs.
Generator performance
- Clause 6 requires the generator to operate in continuous mode and to produce the intended dips, interruptions, and variations without adding disturbances that affect the EUT.
- The generator output voltage range can go up to 120% of the maximum (U_T).
- The output voltage tolerance is ±5% of (U_T), ripple is less than 1%, rise and fall time is between 0.5 µs and 50 µs, and overshoot or undershoot is less than 10% of the voltage change.
- The generator steady-state output current shall be at least 120% of the EUT rated input current.
In practice, this tells the test lab what the source must be able to deliver before the test can be considered valid. If the source cannot meet the generator requirements, the disturbance may not represent the intended condition.
Low impedance and high impedance conditions
- For short interruptions, the generator shall operate either in low impedance condition, where it can absorb reverse current, or in high impedance condition, where it blocks reverse current.
- For dips and voltage variations, the generator shall operate in low impedance condition.
- In low impedance condition, the peak inrush current capability has minimum values linked to (U_T), and lower capability is allowed only when the verification conditions are satisfied.
- In high impedance condition, the output impedance during interruption shall be at least 100 kΩ.
In practice, this distinction matters because some DC systems behave like a stiff source and others like a disconnected source. The test must match the intended network behavior, especially where the load can push current back into the source.
Verifying the generator
- Clause 6.3 requires verification of the generator characteristics with measurement uncertainty better than ±2%.
- Output voltage is verified in no-load and load conditions at specified voltage points.
- Switching characteristics are checked with a 100 Ω resistive load.
- Duration accuracy is verified for 1 ms and 1 s, within ±5% or ±100 µs, whichever is larger.
In practice, this section is what makes the method repeatable. It gives the lab a way to prove the generator actually delivers the disturbance that the test claims to apply.
Test execution, evaluation, and reporting
- Clause 7 requires the shortest power supply cable specified by the EUT operating instructions, or the shortest practical cable if none is specified.
- Clause 8 requires normal operating conditions, a written test plan, and monitoring of the generator output during the test.
- Voltage dips and short interruptions are applied as three events with at least 10 s between events, and voltage variations are also applied three times at 10 s intervals.
- Clause 9 classifies outcomes from normal operation to unrecoverable loss of function or data.
- Clause 10 requires a test report detailed enough to reproduce the test, including EUT identification, test equipment, performance criteria, observed effects, and special use conditions.
In practice, these clauses turn the immunity check into a traceable engineering record, not just a pass/fail statement.
Annex B inrush current measurement
Annex B is normative and gives the method for measuring test generator peak inrush current drive capability and EUT peak inrush current. It specifies the capacitor load, the bleeder resistor, discharge time between tests, and the measurement circuit. It also gives a procedure for cold start and restart measurements on the EUT, which matters when a reduced-capability generator is used.
What terms does SIST EN IEC 61000-4-29:2026 define?
- Immunity - the ability of a device, equipment, or system to keep working without degradation in the presence of an electromagnetic disturbance.
- Voltage dip - a sudden reduction of voltage at a point in a low-voltage DC distribution system, followed by recovery after a short time.
- Short interruption - a supply-voltage change below 20% of nominal voltage for a time interval that typically does not exceed 1 min.
- Voltage variation - a gradual change of supply voltage from rated voltage down to a lower value and then back up.
- Malfunction - loss of the intended function, or unintended operation, of the equipment.
- DC - Direct Current.
- EUT - Equipment Under Test.
Who uses SIST EN IEC 61000-4-29:2026?
SIST EN IEC 61000-4-29:2026 is used by EMC test laboratories, product committees, equipment manufacturers, and verification engineers who need a reproducible immunity test for DC input power ports. It is also relevant to quality managers and buyers who review EMC test plans or reports for acceptance of equipment.
The document is especially relevant for equipment and systems intended for low-voltage DC networks, including modules or subsystems when the full EUT exceeds the generator capacity. Annex C places the context in industrial DC networks, including battery systems, converters, renewable sources, and other LVDC industrial applications.
What changed in SIST EN IEC 61000-4-29:2026 from the previous edition?
SIST EN IEC 61000-4-29:2026 is the second edition and replaces the first edition published in 2000. The document states these significant technical changes:
- increased test generator output voltage to reflect new DC network voltages
- added tolerances for the duration of voltage changes
- limited current when applying short interruptions in low impedance condition
- clarified generator specifications and their verification
- clarified the loads used to verify switching characteristics and peak inrush current drive capability
- clarified evaluation of test results and test reports
- added a description of the DC environment
Which standards are used with SIST EN IEC 61000-4-29:2026?
SIST EN IEC 61000-4-29:2026 is used alongside several IEC documents that appear in the body, annexes, or bibliography:
- IEC 61000-4-17 - covers ripple on d.c. input power ports, which this document excludes from scope.
- IEC 61000-4-11 - provides a similar circuit reference in Annex B for inrush current measurement.
- IEC 60050(161) - supplies the immunity definition used in Clause 3.
- IEC 60038:2021 - provides standard voltages, useful background for rated-voltage discussions.
- IEC SRD 63317:2025 - describes LVDC industry applications and the industrial DC network context used in Annex C.
What does the SIST EN IEC 61000-4-29:2026 document contain?
The document contains three preferred-level tables for dips, interruptions, and voltage variations, plus waveform figures that show how the disturbances are shaped in time. Clause 6 and Annex B provide the generator performance targets and the verification circuits used for inrush current and output-impedance checks.
Clause 7 gives the test set-up rules, while Clause 8 sets out the laboratory conditions, execution sequence, and special cases for high and low impedance interruption tests. Clause 9 defines how to classify the EUT response, and Clause 10 lists the report items needed for reproducible EMC testing.
Annex A gives example generator arrangements, including a two-source switch configuration and a single programmable power supply arrangement. Annex B gives the measurement method and circuit details for inrush current, and Annex C explains the DC network background that motivates the test method.
Relations
- Effective Date
- 01-Dec-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
- Effective Date
- 15-Sep-2026
Get Certified
Connect with accredited certification bodies for this standard
ANCE
Mexican certification and testing association.
Intertek Slovenia
Intertek testing, inspection, and certification services in Slovenia.
LNE (Laboratoire National de Métrologie et d'Essais)
French national laboratory for metrology and testing.
Sponsored listings
Frequently Asked Questions
SIST EN IEC 61000-4-29:2026 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Electromagnetic compatibility (EMC) - Part 4-29: Testing and measurement techniques - Voltage dips, short interruptions and voltage variations on d.c. input power port immunity tests". This standard covers: This part of IEC 61000 defines test methods for immunity to voltage dips, short interruptions and voltage variations at the DC input power port of electrical or electronic equipment. This document is applicable to equipment and systems whose DC input power ports are intended to be connected to low voltage DC networks external to the equipment and systems. The object of this document is to establish a common and reproducible basis for testing electrical and electronic equipment when subjected to voltage dips, short interruptions or voltage variations on DC input power ports. This document defines: – the range of test levels; – the test generator; – the test set-up; – the test procedure. The test described hereinafter applies to electrical and electronic equipment and systems. It also applies to modules or subsystems whenever the equipment under test’s (EUT) rated power is greater than the test generator capacity specified in Clause 6. The ripple at the DC input power port is not included in the scope of this document. It is covered by IEC 61000-4-17. This document does not specify the tests to be applied to particular apparatus or systems. Its main aim is to give a general basic reference to IEC product committees. These product committees (or users and manufacturers of equipment) remain responsible for the appropriate choice of the tests and the severity level to be applied to their equipment.
This part of IEC 61000 defines test methods for immunity to voltage dips, short interruptions and voltage variations at the DC input power port of electrical or electronic equipment. This document is applicable to equipment and systems whose DC input power ports are intended to be connected to low voltage DC networks external to the equipment and systems. The object of this document is to establish a common and reproducible basis for testing electrical and electronic equipment when subjected to voltage dips, short interruptions or voltage variations on DC input power ports. This document defines: – the range of test levels; – the test generator; – the test set-up; – the test procedure. The test described hereinafter applies to electrical and electronic equipment and systems. It also applies to modules or subsystems whenever the equipment under test’s (EUT) rated power is greater than the test generator capacity specified in Clause 6. The ripple at the DC input power port is not included in the scope of this document. It is covered by IEC 61000-4-17. This document does not specify the tests to be applied to particular apparatus or systems. Its main aim is to give a general basic reference to IEC product committees. These product committees (or users and manufacturers of equipment) remain responsible for the appropriate choice of the tests and the severity level to be applied to their equipment.
SIST EN IEC 61000-4-29:2026 is classified under the following ICS (International Classification for Standards) categories: 33.100.20 - Immunity. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN IEC 61000-4-29:2026 has the following relationships with other standards: It is inter standard links to SIST EN 61000-4-29:2003, SIST EN IEC 62984-1:2021, SIST EN IEC 62003:2020, SIST EN 1776:2016, SIST EN 1776:2026, SIST EN 12645:2014, SIST EN IEC 60079-29-0:2026, SIST EN 60987:2015, SIST EN 62271-1:2018, SIST EN IEC 60947-5-3:2026, SIST EN 50270:2015, SIST EN IEC 60143-4:2024, SIST EN 60987:2010, SIST EN IEC 60947-10:2026, SIST EN 12405-2:2013. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
SIST EN IEC 61000-4-29:2026 is associated with the following European legislation: EU Directives/Regulations: 2014/30/EU; Standardization Mandates: M/490. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
SIST EN IEC 61000-4-29:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2026
Nadomešča:
SIST EN 61000-4-29:2003
Elektromagnetna združljivost (EMC) - 4-29. del: Preskusne in merilne tehnike -
Preskusi odpornosti proti upadom napetosti, kratkotrajnim prekinitvam napajanja
in odklonom napetosti za enosmerni (DC) napajalni priključek
Electromagnetic compatibility (EMC) - Part 4-29: Testing and measurement techniques -
Voltage dips, short interruptions and voltage variations on d.c. input power port immunity
tests
Elektromagnetische Verträglichkeit (EMV) - Teil 4-29: Prüf- und Messverfahren -
Prüfungen der Störfestigkeit gegen Spannungseinbrüche, Kurzzeitunterbrechungen und
Spannungsschwankungen an Gleichstrom-Netzeingängen
Compatibilité électromagnétique (CEM) - Partie 4-29: Techniques d'essai et de mesure -
Essais d'immunité aux creux de tension, coupures brèves et varations de tension sur les
accès d'alimentation en courant continu
Ta slovenski standard je istoveten z: EN IEC 61000-4-29:2026
ICS:
33.100.20 Imunost Immunity
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 61000-4-29
NORME EUROPÉENNE
EUROPÄISCHE NORM September 2026
ICS 33.100.20 Supersedes EN 61000-4-29:2000
English Version
Electromagnetic compatibility (EMC) - Part 4-29: Testing and
measurement techniques - Voltage dips, short interruptions and
voltage variations on d.c. input power port immunity tests
(IEC 61000-4-29:2026)
Compatibilité électromagnétique (CEM) - Partie 4-29: Elektromagnetische Verträglichkeit (EMV) - Teil 4-29: Prüf-
Techniques d'essai et de mesure - Creux de tension, und Messverfahren - Prüfungen der Störfestigkeit gegen
coupures brèves et variations de tension sur les accès Spannungseinbrüche, Kurzzeitunterbrechungen und
d'alimentation d'entrée en courant continu Spannungsschwankungen an Gleichstrom-Netzeingängen
(IEC 61000-4-29:2026) (IEC 61000-4-29:2026)
This European Standard was approved by CENELEC on 2026-09-03. 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
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61000-4-29:2026 E
European foreword
The text of document 77A/1276/CDV, future edition 2 of IEC 61000-4-29, prepared by SC 77A "EMC -
Low frequency phenomena" of IEC/TC 77 "Electromagnetic compatibility" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 61000-4-29:2026.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2027-09-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2029-09-30
document have to be withdrawn
This document supersedes EN 61000-4-29:2000 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.
This document has been prepared under a standardization request addressed to CENELEC by the
European Commission. The Standing Committee of the EFTA States subsequently approves these
requests for its Member States.
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 61000-4-29:2026 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 61000-4-11 NOTE Approved as EN IEC 61000-4-11
IEC 61000-4-17 NOTE Approved as EN 61000-4-17
IEC 61000-4-29 ®
Edition 2.0 2026-07
INTERNATIONAL
STANDARD
BASIC EMC PUBLICATION
Electromagnetic compatibility (EMC) -
Part 4-29: Testing and measurement techniques - Voltage dips, short
interruptions and voltage variations on d.c. input power port immunity tests
ICS 33.100.20 ISBN 978-2-8327-1415-7
IEC 61000-4-29:2026-07(en)
IEC 61000-4-29:2026 © IEC 2026
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 6
3.1 Terms and definitions. 6
3.2 Abbreviated terms . 7
4 General . 7
5 Test levels . 8
6 Test generator . 12
6.1 General . 12
6.2 Characteristics and performances of the generator . 13
6.2.1 General . 13
6.2.2 Specific characteristics for the generator operating in "low impedance"
conditions . 13
6.2.3 Specific characteristics for the generator operating in "high impedance"
conditions (short interruption) . 14
6.3 Verification of the characteristics of the generator. 14
6.3.1 General . 14
6.3.2 Output voltage and voltage change . 14
6.3.3 Switching characteristics . 15
6.3.4 Peak inrush current drive capability . 15
6.3.5 Output impedance . 16
6.3.6 Test level duration . 16
7 Test set-up . 16
8 Test procedure . 16
8.1 General . 16
8.2 Laboratory reference conditions . 16
8.2.1 General . 16
8.2.2 Climatic conditions . 16
8.2.3 Electromagnetic conditions . 17
8.3 Execution of the test . 17
8.3.1 General . 17
8.3.2 Voltage dips and short interruptions . 17
8.3.3 Voltage variations . 17
9 Evaluation of test results . 18
10 Test report . 18
Annex A (informative) Example of test generators and test set-up . 19
Annex B (normative) Inrush current measurement. 21
B.1 Test generator peak inrush current drive capability . 21
B.2 EUT peak inrush current . 21
Annex C (informative) Description of the DC network . 23
Bibliography . 24
IEC 61000-4-29:2026 © IEC 2026
Figure 1 – Example of voltage dip . 10
Figure 2 – Example of short voltage interruption . 11
Figure 3 – Examples of voltage variations . 12
Figure A.1 – Example of test generator based on two power sources with switches . 19
Figure A.2 – Example of test generator based on a single programmable power supply . 20
Figure B.1 – Circuit for measuring the peak inrush current drive capability of a test
generator . 22
Figure B.2 – Circuit for measuring the peak inrush current of an EUT . 22
Table 1 – Preferred test levels and durations for voltage dips . 8
Table 2 – Preferred test levels and durations for short voltage interruptions . 9
Table 3 – Preferred test levels and durations for voltage variations. 9
IEC 61000-4-29:2026 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Electromagnetic compatibility (EMC) -
Part 4-29: Testing and measurement techniques -
Voltage dips, short interruptions and voltage variations
on DC input power port immunity tests
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
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
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 61000-4-29 has been prepared by subcommittee 77A: EMC – Low frequency phenomena,
of IEC technical committee 77: Electromagnetic compatibility. It is an International Standard.
It forms part 4-29 of IEC 61000. It has the status of a basic EMC publication in accordance with
IEC Guide 107.
This second edition cancels and replaces the first edition published in 2000. This edition
constitutes a technical revision.
IEC 61000-4-29:2026 © IEC 2026
This edition includes the following significant technical changes with respect to the previous
edition:
a) Increase of the output voltage of the test generator to take into account new DC networks
voltages;
b) provision of tolerances for the duration of the voltage changes;
c) limitation of the current when applying short interruptions in low impedance condition;
d) general technical clarifications for the specifications of the test generator and their
verification;
e) clarifications regarding the loads used to verify the switching characteristics and the peak
inrush current drive capability of the test generator;
f) clarifications regarding the evaluation of test results and test reports;
g) description of the DC environment.
The text of this International Standard is based on the following documents:
Draft Report on voting
77A/1276/CDV 77A/1282/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 61000 series, published under the general title Electromagnetic
compatibility (EMC), can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 61000-4-29:2026 © IEC 2026
INTRODUCTION
IEC 61000 is published in separate parts according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits (in so far as they do not fall under the responsibility of the product
committees)
Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous
Each part is further subdivided into several parts, published either as international standards
or as technical specifications or technical reports, some of which have already been published
as sections. Others will be published with the part number followed by a dash and a second
number identifying the subdivision (example: IEC 61000-6-1).
This part is an international standard which gives immunity requirements for testing DC
equipment and systems with voltage dips, interruptions and variations on the DC input power
port.
IEC 61000-4-29:2026 © IEC 2026
1 Scope
This part of IEC 61000 defines test methods for immunity to voltage dips, short interruptions
and voltage variations at the DC input power port of electrical or electronic equipment.
This document is applicable to equipment and systems whose DC input power ports are
intended to be connected to low voltage DC networks external to the equipment and systems.
The object of this document is to establish a common and reproducible basis for testing
electrical and electronic equipment when subjected to voltage dips, short interruptions or
voltage variations on DC input power ports.
This document defines:
– the range of test levels;
– the test generator;
– the test set-up;
– the test procedure.
The test described hereinafter applies to electrical and electronic equipment and systems. It
also applies to modules or subsystems whenever the equipment under test’s (EUT) rated power
is greater than the test generator capacity specified in Clause 6.
The ripple at the DC input power port is not included in the scope of this document. It is covered
by IEC 61000-4-17.
This document does not specify the tests to be applied to particular apparatus or systems. Its
main aim is to give a general basic reference to IEC product committees. These product
committees (or users and manufacturers of equipment) remain responsible for the appropriate
choice of the tests and the severity level to be applied to their equipment.
2 Normative references
There are no normative references in this document.
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
immunity (to a disturbance)
ability of a device, equipment or system to perform without degradation in the presence of an
electromagnetic disturbance
[SOURCE: IEC 60050-161:1990, 161-01-20]
IEC 61000-4-29:2026 © IEC 2026
3.1.2
voltage dip
sudden reduction of the voltage at a point in the low voltage DC distribution system, followed
by voltage recovery after a short period of time, from a few milliseconds up to a few seconds
3.1.3
short interruption
change of the supply voltage at a point of the low voltage DC distributed system below 20 % of
the nominal voltage for a time interval which typically does not exceed 1 min
Note 1 to entry: A short interruption does not necessarily result in a complete disappearance of the supply voltage.
3.1.4
voltage variation
gradual change of the supply voltage from the rated voltage to a lower voltage or from the rated
voltage to a higher voltage
3.1.5
malfunction
termination of the ability of an equipment to carry out intended functions, or the execution of
unintended functions by the equipment
3.2 Abbreviated terms
DC Direct current
ESR Equivalent series resistance
EUT Equipment under test
LVDC Low-voltage direct current
4 General
The operation of electrical or electronic equipment can be affected by voltage dips, short
interruptions or voltage variations of the power supply.
Voltage dips and short interruptions are mainly caused by faults in the DC distribution system,
or by sudden large changes of load. Two or more consecutive dips or interruptions can also
occur.
Faults in the DC distribution system can inject transient overvoltages into the distribution
network; this particular phenomenon is not covered by this document.
Voltage interruptions are primarily caused by the switching of mechanical relays when changing
from one source to another (e.g. from generator set to battery).
During a short interruption, the DC supply network can present either a "high impedance" or
"low impedance" condition. The first condition can be due to switching from one source to
another; the second condition can be due to the clearing of an overload or fault condition on
the supply bus. The latter can cause reverse current (negative peak inrush current) from the
load.
These phenomena are random in nature and can be characterised in terms of their duration
and the deviation from the nominal voltage. Voltage dips and short interruptions are not always
abrupt.
The primary cause of voltage variations is the discharging and recharging of battery systems;
however, they are also created when there are significant chan
...