IEC 61204-3:2016

Low-voltage switch mode power supplies - Part 3: Electromagnetic compatibility (EMC)

IEC 61204-3:2016 specifies the electromagnetic compatibility (EMC) requirements for switch mode power supply (SMPS) units supplied by source voltages up to 1 000 V AC or 1 500 V DC providing AC and/or DC output(s), except inverter output(s) establishing AC mains. This edition includes the following significant technical changes with respect to the previous edition:
a) the title has been changed by deleting the wording "DC output-" from the title and adding "switch mode" in the title;
b) changes in the scope: 1.1.1 Equipment covered by this document;
c) update of the normative references to the latest editions or dated references;
d) change of wording or/and notes regarding the requirements of CENELEC Guide 24 and IEC Guide 107;
e) revision of the emission limits to align with the latest editions of the applicable normative references;
f) revision of the immunity requirements to align with the latest editions of the applicable normative references;
g) correction of typographical errors.

Alimentations à découpage basse tension - Partie 3: Compatibilité électromagnétique (CEM)

L'IEC 61204-3:2016 spécifie les exigences de compatibilité électromagnétique (CEM) pour les alimentations à découpage (switch mode power supply - SMPS) alimentées par des sources ne dépassant pas 1 000 V en courant alternatif et 1 500 V en courant continu fournissant un courant alternatif et/ou continu, à l'exception de la ou des sorties de l'onduleur alimentant le réseau en courant alternatif. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) modification du titre avec la suppression des termes "sortie continue" et l'ajout des termes "à découpage";
b) modifications dans le domaine d'application: 1.1.1 Matériel couvert par le présent document;
c) mise à jour des références normatives pour mentionner les dernières éditions ou les références datées;
d) modifications de la formulation et/ou des notes relatives aux exigences du Guide 24 du CENELEC et du Guide 107 de l'IEC;
e) révisions des limites relatives aux émissions pour les aligner avec celles des dernières versions des références normatives applicables;
f) révisions des exigences relatives à l'immunité pour les aligner avec celles des dernières versions des références normatives applicables;
g) correction d'ordre typographiques.

General Information

• Status: Published
• Publication Date: 27-Oct-2016
• ICS: 29.140.40 - Luminaires
• ICS: 29.200 - Rectifiers. Convertors. Stabilized power supply
• ICS: 33.100 - Electromagnetic compatibility (EMC)
• Technical Committee: SC 22E - Stabilized power supplies
• Drafting Committee: MT 5 - TC 22/SC 22E/MT 5
• Current Stage: PPUB - Publication issued
• Start Date: 28-Oct-2016
• Completion Date: 30-Nov-2016

Relations

• Revises: IEC 61204-3:2011 - Low voltage power supplies, d.c. output - Part 3: Electromagnetic compatibility (EMC)
• Effective Date: 05-Sep-2023

Overview

IEC 61204-3:2016 - Low‑voltage switch mode power supplies - Part 3: Electromagnetic compatibility (EMC) - specifies EMC requirements for switch mode power supply (SMPS) units supplied by source voltages up to 1 000 V AC or 1 500 V DC, providing AC and/or DC outputs. The standard excludes inverter outputs that establish AC mains. This third edition updates scope, normative references and aligns emission and immunity limits with current IEC/CENELEC guidance.

Key topics and requirements

• Scope & applicability
  • Applies to SMPS (low‑voltage) including AC/DC and DC/DC topologies (except full inverters for mains generation).
  • Clarifies equipment types, configurations and exclusions (see clause 1.1.x).
• Emission requirements
  • Low‑frequency phenomena (commutation notches, current harmonics, flicker).
  • High‑frequency conducted emissions for input and DC output ports.
  • High‑frequency radiated emissions and disturbance power measurement (measurement methods defined).
  • Emission limits updated to align with latest normative references (Annex H contains emission limits).
• Immunity requirements
  • Performance criteria and test levels for different environments: residential, commercial/light industrial and industrial.
  • Immunity tests cover high‑frequency disturbances, enclosure ports, signal/control ports, DC/AC input and output ports (see Tables 2–9).
• Test conditions and reporting
  • Standard defines general test conditions, classification of ports, statistical aspects, safety considerations and required test report contents.
• Special considerations
  • Guidance for DC/DC converters, power supply families and disturbance power measurement methods (informative and normative annexes).

Practical applications - who uses this standard

• SMPS manufacturers - design to meet EMC limits, select filters, shielding and grounding strategies.
• EMC test labs - implement measurement procedures for conducted and radiated emissions and immunity verification.
• Product compliance engineers - prepare compliance dossiers and test reports for certification and market access.
• System integrators and OEMs - ensure power supplies meet EMC requirements for target environments (residential vs industrial).
• Regulatory and certification bodies - evaluate conformity to IEC EMC requirements for low‑voltage power supplies.

Benefits and SEO keywords

Using IEC 61204-3:2016 helps reduce interference, improve product reliability and achieve compliance for low‑voltage switch mode power supplies, EMC compliance, conducted emission, radiated emission, immunity testing, harmonics, and flicker. The standard is essential for anyone designing, testing or certifying SMPS for commercial or industrial markets.

Related standards

• Normative references are updated in this edition - consult the standard’s Normative references clause for linked CISPR/IEC EMC standards and guides (CENELEC Guide 24, IEC Guide 107) to ensure full compliance.

Note: Always obtain and use the latest official IEC publication and applicable corrigenda when applying IEC 61204-3:2016 in product development or testing.

Standards Content (Sample)

IEC 61204-3 ®
Edition 3.0 2016-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Low-voltage switch mode power supplies, d.c. output –
Part 3: Electromagnetic compatibility (EMC)

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IEC 61204-3 ®
Edition 3.0 2016-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Low-voltage switch mode power supplies, d.c. output –

Part 3: Electromagnetic compatibility (EMC)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.200; 33.100 ISBN 978-2-8322-3734-2

– 2 – IEC 61204-3:2016 RLV © IEC 2016
CONTENTS
FOREWORD . 4
1 Scope and object . 6
1.1 Scope . 6
1.1.1 Equipment covered by this document . 6
1.1.2 Additional requirements . 6
1.1.3 Exclusions . 6
1.1.4 Types of power supply . 7
1.1.5 Configurations and combinations of power supplies . 7
1.2 Object . 8
2 Normative references . 8
3 Terms and definitions . 10
4 Applicability of tests to different PSU technologies . 14
5 General requirements and test conditions . 14
5.1 General requirements . 14
5.2 Test conditions . 14
6 Emission requirements . 15
6.1 General . 15
6.2 Low frequency phenomena (f ≤ 9 kHz; AC input only) . 15
6.2.1 Commutation notches . 15
6.2.2 Current harmonics and interharmonics . 15
6.2.3 Voltage fluctuations and flicker . 16
6.3 High frequency conducted emission . 16
6.3.1 General . 16
6.3.2 High frequency conducted emission for input power ports . 16
6.3.3 High frequency conducted emission for DC output power ports . 16
6.4 High frequency radiated emission . 16
6.4.1 General . 16
6.4.2 Radiated disturbance measurements . 17
6.4.3 Measurement of disturbance power . 17
6.4.4 Restrictions for the application of interference power measurement . 18
7 Immunity requirements . 19
7.1 Performance criteria . 19
7.2 Basic immunity requirements, high frequency disturbances . 19
7.2.1 General . 19
7.2.2 Immunity level for residential, commercial and light industrial
environment . 20
7.2.3 Immunity level for industrial environment . 22
8 Power supply families aspects . 25
9 Statistical aspects . 26
10 Safety aspects . 26
11 Test report . 26
Annex A (normative) Guidelines on the classification of PSUs . 27
A.1 General . 27
A.2 Stand alone power supplies . 27
A.3 Component power supplies . 27

Annex B (informative) Commutation notches . 29
Annex C (informative) Calculation and simulation of the input current harmonics . 30
Annex D (informative) Special considerations for DC/DC converters . 31
D.1 General . 31
D.2 Emission . 31
D.3 Immunity . 31
Annex E (informative) Critical frequency for high frequency power measurement . 34
Annex F (normative) Guidelines on power supply families . 35
F.1 General . 35
F.2 Emission . 35
F.3 Immunity performance . 35
Annex G (informative) Summary of classification of environments and limits . 37
G.1 Residential, commercial and light industrial environment . 37
G.2 Industrial environment . 37
G.3 Special applications . 37
G.4 Special considerations for DC/DC converters . 38
Annex H (normative) Emission limits . 39
Bibliography . 41

Figure 1 – Examples of ports . 11
Figure 2 – Test set-up for the measurement of disturbance power . 18

Table 1 – Criteria to prove the performance of a PSU against EM disturbances . 19
Table 2 – Immunity – Enclosure port – Residential, commercial and light industrial
environment . 20
Table 3 – Immunity – Ports for signal lines and control lines
Residential, commercial and light industrial environment . 21
Table 4 – Immunity – DC input and output power ports
Residential, commercial and light industrial environment . 21
Table 5 – Immunity – AC input power ports – Residential, commercial and light
industrial environment . 22
Table 6 – Immunity – Enclosure port – Industrial environment . 23
Table 7 – Immunity – Ports for signal lines and control lines – Industrial environment . 23
Table 8 – Immunity – DC input and output power ports – Industrial environment . 24
Table 9 – Immunity – AC input power ports – Industrial environment. 25
Table A.1 – Classification of power supplies and the relevant EMC standards . 28
Table D.1 – Immunity – DC input power ports – Input category a . 32
Table D.2 – Immunity – DC input power ports – Input category b . 32
Table D.3 – Immunity – Enclosure port – Input categories a and b . 33
Table H.1 – Limits of mains terminal disturbance voltage (AC input port) . 39
Table H.2 – Limits of mains terminal disturbance voltage (DC input and DC output
power port) . 39
Table H.3 – Limits for electromagnetic radiation/interference power disturbance (all
field strength limits refer to quasi-peak measurements) . 40
Table H.4 – Disturbance power limits for the frequency range 30 MHz to 300 MHz . 40

– 4 – IEC 61204-3:2016 RLV © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE SWITCH MODE POWER SUPPLIES, d.c. OUTPUT –

Part 3: Electromagnetic compatibility (EMC)

FOREWORD
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This redline version of the official IEC Standard allows the user to identify the changes
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International Standard IEC 61204-3 has been prepared by subcommittee 22E: Stabilized
power supplies, of IEC technical committee 22: Power electronic systems and equipment.
IEC 61204-3 has the status of a product family standard.
This third edition cancels and replaces the second edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the title has been changed by deleting the wording "DC output-" from the title and adding
"switch mode" in the title;
b) changes in the scope: 1.1.1 Equipment covered by this document;
c) update of the normative references to the latest editions or dated references;
d) change of wording or/and notes regarding the requirements of CENELEC Guide 24 and
IEC Guide 107;
e) revision of the emission limits to align with the latest editions of the applicable normative
references;
f) revision of the immunity requirements to align with the latest editions of the applicable
normative references;
g) correction of typographical errors.
The text of this standard is based on the following documents:
FDIS Report on voting
22E/174/FDIS 22E/176/RVD
Full information on the voting for the approval of this document can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 61204 series, under the general title Low-voltage power supplies, d.c.
output, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

– 6 – IEC 61204-3:2016 RLV © IEC 2016
LOW-VOLTAGE SWITCH MODE POWER SUPPLIES, d.c. OUTPUT –

Part 3: Electromagnetic compatibility (EMC)

1 Scope and object
1.1 Scope
1.1.1 Equipment covered by this document
This part of IEC 61204 specifies the electromagnetic compatibility (EMC) requirements for
power supply units (PSUs) providing d.c. output(s) with or without auxiliary a.c. output(s),
operating from a.c. or d.c. source voltages up to 600 V a.c. or 1 000 V d.c. switch mode power
supply (SMPS) units supplied by source voltages up to 1 000 V AC or 1 500 V DC providing
AC and/or DC output(s), except inverter output(s) establishing AC mains (see exceptions
under 1.1.3.)
NOTE 1 This document by definition covers DC/DC converters.
NOTE 2 Power supplies can provide accessory AC mains socket outlets, when such outputs are supplied from the
AC mains.
NOTE 3 Ringing generators used in telecoms applications are covered by this document.
This product standard covers both stand alone and component power supply (PSU) units as
defined in this document. It covers PSU units for use in or with IT equipment normally covered
by IEC 60950-1:2001 and/or IEC 60950-1:2005 62368-1; PSU units for use in or with
measurement, control and laboratory equipment normally covered by IEC 61010-1; PSU units
for use in or with medical equipment – normally covered by IEC 60601-1; PSU units for use in
or with audio, video and similar electronic apparatus – normally covered by IEC 60065 and/or
IEC 62368-1. It also covers DC power and distribution equipment and DC/DC converters.
Where no standard exist, use of this document for other applications is not precluded.
1.1.2 Additional requirements
Requirements additional to those specified in this document may be necessary for
• PSUs intended for operation in special environments (for example, extremes of
temperature; excessive dust, moisture or vibration; flammable gases; and corrosive or
explosive atmospheres);
• PSUs intended to be used in vehicles, on board ships or aircraft, or in tropical countries;
• PSUs intended for use where ingress of water is possible.
NOTE Attention is drawn to the fact that authorities in some countries impose additional requirements for health,
environmental and similar reasons.
1.1.3 Exclusions
This document does not apply to
• motor-generator sets;
• uninterruptible power supplies (UPS) to IEC 62040-1-1;
___________
This publication has been withdrawn and replaced by the second edition issued in 2005.

• PSUs covered by IEC 61558-1 (i.e. power supply units incorporating safety isolating
transformers providing SELV or PELV output(s) in accordance with IEC 60364-4-41) and
PSUs for use with household and other consumer products, except those covered by
IEC 60065 and IEC 60950-1:2001 and/or IEC 60950-1:2005 62368-1;
• transformers covered by IEC 61558-1;
• step-down converters covered by IEC 60146-1-1;
• PSUs and converters for use with or in products covered by IEC 61347-2-2 intended for
DC supplied bulb lamps, halogen lamps or LED lamps covered by CISPR 15.
1.1.4 Types of power supply
Two types of power supplies are covered by this document:
a) stand alone (or end-product) power supplies
Power supplies intended for free-standing operation (individual apparatus).
This part of IEC 61204 is applicable to PSUs developed as a unit with a direct function
and sold on the market as a stand alone unit.
b) component power supplies
These can be divided into two categories:
1) component power supplies considered as equivalent to stand alone power
supplies (apparatus)
This part of IEC 61204 is applicable to this category of component PSUs. These PSUs
are considered to be apparatus with respect to their EMC requirements, for example
those PSUs intended for use in installations or sold to the general public, cases where
no further EMC tests are anticipated. This does not include PSUs sold as spares for
repair which have been tested as part of an overall equipment.
2) component power supplies intended for a professional installer
This part of IEC 61204 is applicable to this category of power supplies only as an aid
to specify relevant EMC requirements in order that various end-product standards may
be met.
These are component power supplies that are intended for incorporation into a final
product by a professional installer. These products may be sold to a professional
installer or placed on the market for specialized distribution and use. In neither case do
they perform in themselves a direct function for the user of an end-product. Further
EMC tests of the assembly are assumed.
NOTE After incorporation into a final product, the emission values can be altered (e.g. because of modified earth
connections).
1.1.5 Configurations and combinations of power supplies
1.1.5.1 Modular PSUs
A PSU with a single primary circuit or module and separate output modules forming a single
unit, synchronized or not, shall meets the requirements defined in this document as a single
component or apparatus type of PSU.
1.1.5.2 Power supply systems
An easily relocatable system containing several PSUs in parallel, in series or combination
with a single input connection shall comply complies with this document as a single
component or apparatus type of PSU. It is the responsibility of the system supplier to ensure
EMC compliance with this document or with a specific EMC standard of the end product.

– 8 – IEC 61204-3:2016 RLV © IEC 2016
1.1.5.3 Power supply installations
When a number of PSUs are used in an installation and are supplied by a distributed AC or
DC network, then this is a power installation. This type of arrangement is not easily
relocatable. Each individual PSU complies with this document and this is the responsibility of
the PSU manufacturer who also provides information on the correct installation of his product.
The EMC considerations of the final installation are the responsibility of the professional
installer.
1.1.5.4 Distributed power supplies
This is a power installation where the input AC or DC supply is distributed to individual power
conversion units or modules which are installed locally to the circuitry to be supplied. This
document applies to the individual products as appropriate. The EMC performance of the
overall system or installation is the responsibility of the professional installer.
1.1.5.5 Power supplies in parallel or in series
Where PSUs are sold to be connected in parallel or in series, their documentation shall
include information relating to the expected EMC performance for such arrangements.
1.2 Object
The object of this part of IEC 61204 is to define EMC limits and test methods for PSUs. It
includes limits for electromagnetic emissions which may cause interference to other electronic
equipment (e.g. radio receivers, measuring and computer devices), as well as
electromagnetic immunity limits for continuous and transient conducted and radiated
disturbances including electrostatic discharges.
This part of IEC 61204 defines the minimum electromagnetic compatibility requirements for
PSUs.
To comply with this part of IEC 61204, no additional EMC tests are required or necessary
beyond those stated here.
2 Normative references
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.
IEC 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism
IEC 60050-131, International Electrotechnical Vocabulary (IEV) – Part 131: Circuit theory
IEC 60050-151, International Electrotechnical Vocabulary – Part 151: Electrical and magnetic
devices
IEC 60050-161, International Electrotechnical Vocabulary – Part 161: Electromagnetic
compatibility
IEC 60050-551, International Electrotechnical Vocabulary – Part 551: Power electronics
IEC 60065, Audio, video and similar electronic apparatus – Safety requirements

IEC 60146-1-1, Semiconductor converters – General requirements and line commutated
converters – Part 1-1: Specifications of basic requirements
IEC 60364-4-41, Low-voltage electrical installations – Part 4-41: Protection for safety –
Protection against electric shock
IEC 60601-1, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60950-1:2005, Information technology equipment – Safety – Part 1: General requirements
IEC 61000-3-2:2014, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for
harmonic current emissions (equipment input current ≤16 A per phase)
IEC 61000-3-3, Electromagnetic compatibility (EMC) – Part 3-3: Limits – Limitation of voltage
changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment
with rated current ≤16 A per phase and not subject to conditional connection
IEC 61000-3-11 Electromagnetic compatibility (EMC) – Part 3-11: Limits – Limitation of
voltage changes, voltage fluctuations and flicker in public low-voltage supply systems –
Equipment with rated current ≤75 A and subject to conditional connection
IEC 61000-3-12, Electromagnetic compatibility (EMC) – Part 3-12: Limits – Limits for
harmonic currents produced by equipment connected to public low-voltage systems with input
current >16 A and ≤75 A per phase
IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4-2: Testing and measurement
techniques – Electrostatic discharge immunity test
IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measurement
techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement
techniques – Electrical fast transient/burst immunity test
IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4-5: Testing and measurement
techniques – Surge immunity test
IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement
techniques – Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-4-8, Electromagnetic compatibility (EMC) – Part 4-8: Testing and measurement
techniques – Power frequency magnetic field immunity test
IEC 61000-4-11, Electromagnetic compatibility (EMC) – Part 4-11: Testing and measuring
techniques – Voltage dips, short interruptions and voltage variations immunity tests
IEC 61000-6-1, Electromagnetic compatibility (EMC) – Part 6-1: Generic standards –
Immunity for residential, commercial and light-industrial environments
IEC 61000-6-2, Electromagnetic compatibility (EMC) – Part 6-2: Generic standards –
Immunity for industrial environments
IEC 61000-6-3, Electromagnetic compatibility (EMC) – Part 6-3: Generic standards –
Emission standard for residential, commercial and light-industrial environments

– 10 – IEC 61204-3:2016 RLV © IEC 2016
IEC 61000-6-4, Electromagnetic compatibility (EMC) – Part 6-4: Generic standards –
Emission standard for industrial environments
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 61204, Low-voltage power supply devices, d.c. output – Performance characteristics
IEC 61347-2-2, Lamp controlgear – Part 2-2: Particular requirements for d.c. or a.c. supplied
electronic step-down converters for filament lamps
IEC 61558-1, Safety of power transformers, power supplies, reactors and similar products –
Part 1: General requirements and tests
IEC 62368-1, Audio/video, information and communication technology equipment – Part 1:
Safety requirements
CISPR 11, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
CISPR 14-1, Electromagnetic compatibility – Requirements for household appliances, electric
tools and similar apparatus – Part 1: Emission
CISPR 16-1 (all parts), Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 16-1-2:2004 2014, Specification for radio disturbance and immunity measuring
apparatus and methods – Part 1-2: Radio disturbance and immunity measuring apparatus –
Ancillary equipment – Coupling devices for conducted disturbances measurements
CISPR 16-1-3, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1-3: Radio disturbance and immunity measuring apparatus – Ancillary
equipment – Disturbance power
CISPR 16-2-1:2008 2014, Specification for radio disturbance and immunity measuring
apparatus and methods – Part 2-1: Methods of measurement of disturbances and immunity –
Conducted disturbance measurements
CISPR 16-2-2, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 2-2: Methods of measurement of disturbances and immunity – Measurement
of disturbance power
CISPR 16-2-3, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 2-3: Methods of measurement of disturbances and immunity – Radiated
disturbance measurements
CISPR 22, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-121,
IEC 60050-151, IEC 60050-161, IEC 60050-551, IEC 60146-1-1 and the following apply.
___________
Future IEC 61204-2.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
environment
3.1.1
residential, commercial and light industrial environment
environment encompassed by the generic standard IEC 61000-6-3
Note 1 to entry: An indication of the locations included by this environment is given in Annex G.
3.1.2
industrial environment
environment encompassed by the generic standard IEC 61000-6-4
Note 1 to entry: An indication of the locations included by this environment is given in Annex G.
3.2
protection distance
distance for an electronic or electrical apparatus beyond which the interference levels shall
not impair the use of other electronic or electrical equipment, for example broadcast radio and
television receivers
3.3
distributed power system
system of localized power converters supplied from a distributed power bus
3.4
port
particular interface of a product with the external electromagnetic environment
[IEC 60050-131:2002, 131-02-21 modified]
Note 1 to entry: Examples of ports are given in Figure 1:
Enclosure port
AC input power port DC output power port

DC input power port
PSU
Signal/control line port
IEC
Figure 1 – Examples of ports
3.4.1
enclosure port
physical boundary of the PSU product through which and on which electromagnetic fields may
radiate or impinge
– 12 – IEC 61204-3:2016 RLV © IEC 2016
3.4.2
signal or control line port
low energy level input or output port providing diagnostic or control information
3.4.3
DC input power port
external DC energy source connection point
3.4.4
DC output power port
external connection point for providing output DC energy
3.4.5
AC input power port
external AC energy source connection point
3.5
power supply
PSU
electrical or electronic device which transforms energy from an input source into a single or
multiple output energy source
3.5.1
component power supply
modular PSU
sub-unit PSU
assemblies of electrical and/or electronic devices designed to provide or modify energy
Note 1 to entry: They are intended for incorporation into end-products by a professional installer. They are not
intended for free-standing applications.
3.5.2
stand alone power supply
intended for use in laboratories, workshops and other areas in free-standing applications
Note 1 to entry: They are end-products, completely enclosed with full protection against electrostatic discharge
and contact with hazardous parts which are accessible to the end-user. Typical examples include adjustable or
fixed output bench-top units, plug-top units, free-standing and wall-mounted units.
3.5.3
bench-top power supply
supply intended for laboratory or similar use
Note 1 to entry: They are stand alone PSUs, sometimes with monitoring and measuring facilities.
3.5.4
open card power supply
frameless PSU
printed circuit board devoid of a metal mounting bracket
Note 1 to entry: It is a component PSU intended for use by a installer.
3.5.5
open frame power supply
supply that generally uses a printed circuit board mounted on a metal bracket for attachment
to the professional installer's equipment chassis
Note 1 to entry: This bracket provides heat transfer for the cooling of power semiconductors. Optionally, a cover
may be used for safety reasons and/or to reduce radiated interference.

3.5.6
plug-in card power supply
supply intended to be plugged into a subrack
Note 1 to entry: The design may be "open-card", "open-frame" or "cased". A plug-in card PSU is generally
intended for use by a professional installer.
3.5.7
cased power supply
enclosed power supply
supply fully enclosed, cased or housed PSU
Note 1 to entry: The design uses the housing as a heat sink or employs fan(s) for forced air cooling.
3.5.8
plug-top power supply
direct plug-in power supply
power supply built into a mains voltage plug top
3.5.9
uninterruptible power supply
UPS
supply intended to provide a source of energy secure against mains failure
Note 1 to entry: This type of product would normally be free-standing.
3.6
end-product
finished unit which is designed to stand alone, useable by an end-user and having a direct
function for the end-user
Note 1 to entry: It is intended to be placed on the market and/or taken into service as a single unit or as part of a
system or installation.
3.7
system
localized group of interconnected products which is easily relocatable
Note 1 to entry: Typical examples of this would be a computer, including mouse, keyboard, printer and monitor, or
a hi-fi system, TV and video recorder.
3.8
installation
collection of interconnected products which is not easily relocatable
Note 1 to entry: Typical examples of this include an industrial process installation or a power plant control
installation.
3.9
non-professional
person or organization assumed to have little or no technical knowledge or facilities
3.9
professional installer
technically competent person or organization capable of correctly assembling/installing
components and subassemblies into an end-product, or end-products into a system or
installation, and, in so doing, fully complying with the technical and legal requirements of the
end-product, system or installation
3.10
full rated load
maximum continuous or average power a product is marked to supply

– 14 – IEC 61204-3:2016 RLV © IEC 2016
3.11
mains supply
3.11.1
industrial mains supply
source of electrical energy provided solely for industrial use
3.11.2
private mains supply
localized source of electrical energy (e.g. generator or UPS) which is not directly connected to
the public network
3.11.3
public mains supply
source of electrical energy provided for general public use in domestic, commercial or light
industrial environments
3.12
critical frequency of a PSU
the frequency, the wavelength of which is equal to four times the longest side length of the
PSU
3.13
residual voltage
minimum value of RMS voltage recorded during a voltage dip or short
interruption
Note 1 to entry: The residual voltage may be expressed as a value in volts, or as a percentage or per unit value
relative to the reference voltage.
3.14
type test
conformity test made on one or more items representative of the production
[SOURCE: IEC 60050-151:2001, 151-16-16]
4 Applicability of tests to different PSU technologies
Guidance on this issue is given in Annex A.
5 General requirements and test conditions
5.1 General requirements
The manufacturer of the PSU has a responsibility to provide information relating to the EMC
performance, application, intended environment and installation guidelines for the product.
5.2 Test conditions
The tests shall be performed using the manufacturer’s recommended wiring and installation
instructions. There will be no connections other than those specified by the manufacturer.
The configuration, orientation and electrical test conditions of the PSU shall be representative
of the worst case in-service conditions, if known. Otherwise, all measurements shall be
performed at rated nominal input voltage, full rated load and ambient temperature between
15 °C and 35 °C. The PSU shall be at its normal operating temperature.

The load is presumed not to generate any electromagnetic interference disturbance. Load
resistors may be cooled by a fan or cooling fluid.
All tests specified in this document are type tests only.
The equipment shall meet the requirements when measured by the test methods specified.
No additional EMC tests are required or necessary beyond those stated in this standard.
A PSU device is deemed to fulfill the requirements specified in this document if it complies
with the defined functional and performance requirements using the test methods specified in
this document.
Precautions shall be taken against the EUT (equipment under test) becoming dangerous or
unsafe as a result of the immunity tests specified in this document.
6 Emission requirements
6.1 General
If the cable arrangements of the application are known, then those shall be used. If they are
not known, the arrangements shall be chosen in accordance with 6.3 and 6.4. The measuring
conditions cable arrangement implemented during the test shall be stated in the
documentation.
6.2 Low frequency phenomena (f ≤ 9 kHz; AC input only)
6.2.1 Commutation notches
In this subclause, only PSUs with commutation of the primary current are covered. PSUs of
high power designed as line commutated converters may cause notches if connected to a
high impedance source. Measurements or calculations are not mandatory. Information and
recommendations are given in Annex B.
6.2.2 Current harmonics and interharmonics
The limits for PSUs connected to a public mains supply up to and including a rated input
current of 16 A are given in IEC 61000-3-2. This requirement is applicable to apparatus and
components considered as apparatus covered within the scope of IEC 61000-3-2.
NOTE Limits for harmonic currents produced by equipment connected to public low-voltage systems with input
current >16 A and ≤75 A per phase are given in IEC 61000-3-12.
Harmonic measurements, especially on PSUs, are sensitive to the voltage source. In many
cases, the public mains supply may not be a suitable source for this purpose.
Therefore, one of the following methods shall be used.
a) Using a public mains supply in accordance with the related standard IEC 61000-3-2 or
IEC 61000-3-12:
– the limits for the harmonics of the voltage source shall be met with the PSU operating
at full rated load.
b) Using an artificial supply in accordance with the related standard IEC 61000-3-2 or
IEC 61000-3-12.
c) Calculation or simulation if it takes into account in accordance with the related standard
IEC 61000-3-12:
– usage of the voltage source as an ideal sine wave;

– 16 – IEC 61204-3:2016 RLV © IEC 2016
– notice the worst case internal impedance of the PSU in the frequency range from the
line frequency up to the 40th harmonic.
For recommendations: see Annex C. Interharmonics may occur under specific load condition
...

IEC 61204-3 ®
Edition 3.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switch mode power supplies –
Part 3: Electromagnetic compatibility (EMC)

Alimentations à découpage basse tension –
Partie 3: Compatibilité électromagnétique (CEM)

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IEC 61204-3 ®
Edition 3.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switch mode power supplies –

Part 3: Electromagnetic compatibility (EMC)

Alimentations à découpage basse tension –

Partie 3: Compatibilité électromagnétique (CEM)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.200; 33.100 ISBN 978-2-8322-3689-5

– 2 – IEC 61204-3:2016 © IEC 2016
CONTENTS
FOREWORD . 4
1 Scope and object . 6
1.1 Scope . 6
1.1.1 Equipment covered by this document . 6
1.1.2 Additional requirements . 6
1.1.3 Exclusions . 6
1.1.4 Types of power supply . 7
1.1.5 Configurations and combinations of power supplies . 7
1.2 Object . 8
2 Normative references . 8
3 Terms and definitions . 10
4 Applicability of tests to different PSU technologies . 13
5 General requirements and test conditions . 14
5.1 General requirements . 14
5.2 Test conditions . 14
6 Emission requirements . 14
6.1 General . 14
6.2 Low frequency phenomena (f ≤ 9 kHz; AC input only) . 14
6.2.1 Commutation notches . 14
6.2.2 Current harmonics and interharmonics . 14
6.2.3 Voltage fluctuations and flicker . 15
6.3 High frequency conducted emission . 15
6.3.1 General . 15
6.3.2 High frequency conducted emission for input power ports . 15
6.3.3 High frequency conducted emission for DC output power ports . 16
6.4 High frequency radiated emission . 16
6.4.1 General . 16
6.4.2 Radiated disturbance measurements . 16
6.4.3 Measurement of disturbance power . 16
6.4.4 Restrictions for the application of interference power measurement . 17
7 Immunity requirements . 18
7.1 Performance criteria . 18
7.2 Basic immunity requirements, high frequency disturbances . 18
7.2.1 General . 18
7.2.2 Immunity level for residential, commercial and light industrial
environment . 18
7.2.3 Immunity level for industrial environment . 21
8 Power supply families aspects . 24
9 Statistical aspects . 25
10 Safety aspects . 25
11 Test report . 25
Annex A (normative) Guidelines on the classification of PSUs . 26
A.1 General . 26
A.2 Stand alone power supplies . 26
A.3 Component power supplies . 26

Annex B (informative) Commutation notches . 28
Annex C (informative) Calculation and simulation of the input current harmonics . 29
Annex D (informative) Special considerations for DC/DC converters . 30
D.1 General . 30
D.2 Emission . 30
D.3 Immunity . 30
Annex E (informative) Critical frequency for high frequency power measurement . 33
Annex F (normative) Guidelines on power supply families . 34
F.1 General . 34
F.2 Emission . 34
F.3 Immunity performance . 34
Annex G (informative) Summary of classification of environments and limits . 36
G.1 Residential, commercial and light industrial environment . 36
G.2 Industrial environment . 36
G.3 Special applications . 36
G.4 Special considerations for DC/DC converters . 37
Annex H (normative) Emission limits . 38
Bibliography . 40

Figure 1 – Examples of ports . 11
Figure 2 – Test set-up for the measurement of disturbance power . 17

Table 1 – Criteria to prove the performance of a PSU against EM disturbances . 18
Table 2 – Immunity – Enclosure port – Residential, commercial and light industrial
environment . 19
Table 3 – Immunity – Ports for signal lines and control lines Residential, commercial
and light industrial environment . 19
Table 4 – Immunity – DC input and output power ports Residential, commercial and
light industrial environment . 20
Table 5 – Immunity – AC input power ports – Residential, commercial and light
industrial environment . 21
Table 6 – Immunity – Enclosure port – Industrial environment . 22
Table 7 – Immunity – Ports for signal lines and control lines – Industrial environment . 22
Table 8 – Immunity – DC input and output power ports – Industrial environment . 23
Table 9 – Immunity – AC input power ports – Industrial environment. 24
Table A.1 – Classification of power supplies and the relevant EMC standards . 27
Table D.1 – Immunity – DC input power ports – Input category a . 31
Table D.2 – Immunity – DC input power ports – Input category b . 31
Table D.3 – Immunity – Enclosure port – Input categories a and b . 32
Table H.1 – Limits of mains terminal disturbance voltage (AC input port) . 38
Table H.2 – Limits of mains terminal disturbance voltage (DC input and DC output
power port) . 38
Table H.3 – Limits for electromagnetic radiation/interference power disturbance (all
field strength limits refer to quasi-peak measurements) . 39
Table H.4 – Disturbance power limits for the frequency range 30 MHz to 300 MHz . 39

– 4 – IEC 61204-3:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE SWITCH MODE POWER SUPPLIES –

Part 3: Electromagnetic compatibility (EMC)

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61204-3 has been prepared by subcommittee 22E: Stabilized
power supplies, of IEC technical committee 22: Power electronic systems and equipment.
IEC 61204-3 has the status of a product family standard.
This third edition cancels and replaces the second edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the title has been changed by deleting the wording "DC output-" from the title and adding
"switch mode" in the title;
b) changes in the scope: 1.1.1 Equipment covered by this document;
c) update of the normative references to the latest editions or dated references;

d) change of wording or/and notes regarding the requirements of CENELEC Guide 24 and
IEC Guide 107;
e) revision of the emission limits to align with the latest editions of the applicable normative
references;
f) revision of the immunity requirements to align with the latest editions of the applicable
normative references;
g) correction of typographical errors.
The text of this standard is based on the following documents:
FDIS Report on voting
22E/174/FDIS 22E/176/RVD
Full information on the voting for the approval of this document can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 61204 series, under the general title Low-voltage power supplies, d.c.
output, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 6 – IEC 61204-3:2016 © IEC 2016
LOW-VOLTAGE SWITCH MODE POWER SUPPLIES –

Part 3: Electromagnetic compatibility (EMC)

1 Scope and object
1.1 Scope
1.1.1 Equipment covered by this document
This part of IEC 61204 specifies the electromagnetic compatibility (EMC) requirements for
switch mode power supply (SMPS) units supplied by source voltages up to 1 000 V AC or
1 500 V DC providing AC and/or DC output(s), except inverter output(s) establishing AC
mains (see exceptions under 1.1.3.)
NOTE 1 This document by definition covers DC/DC converters.
NOTE 2 Power supplies can provide accessory AC mains socket outlets, when such outputs are supplied from the
AC mains.
NOTE 3 Ringing generators used in telecoms applications are covered by this document.
This product standard covers both stand alone and component power supply (PSU) units as
defined in this document. It covers PSU units for use in or with IT equipment normally covered
by IEC 60950-1 and/or IEC 62368-1; PSU units for use in or with measurement, control and
laboratory equipment normally covered by IEC 61010-1; PSU units for use in or with medical
equipment – normally covered by IEC 60601-1; PSU units for use in or with audio, video and
similar electronic apparatus – normally covered by IEC 60065 and/or IEC 62368-1. It also
covers DC power and distribution equipment and DC/DC converters.
Where no standard exist, use of this document for other applications is not precluded.
1.1.2 Additional requirements
Requirements additional to those specified in this document may be necessary for
• PSUs intended for operation in special environments (for example, extremes of
temperature; excessive dust, moisture or vibration; flammable gases; and corrosive or
explosive atmospheres);
• PSUs intended to be used in vehicles, on board ships or aircraft, or in tropical countries;
• PSUs intended for use where ingress of water is possible.
NOTE Attention is drawn to the fact that authorities in some countries impose additional requirements for health,
environmental and similar reasons.
1.1.3 Exclusions
This document does not apply to
• motor-generator sets;
• uninterruptible power supplies (UPS) to IEC 62040-1;
• PSUs covered by IEC 61558-1 (i.e. power supply units incorporating safety isolating
transformers providing SELV or PELV output(s) in accordance with IEC 60364-4-41) and
PSUs for use with household and other consumer products, except those covered by
IEC 60065 and IEC 60950-1 and/or IEC 62368-1;
• transformers covered by IEC 61558-1;

• step-down converters covered by IEC 60146-1-1;
• PSUs and converters intended for DC supplied bulb lamps, halogen lamps or LED lamps
covered by CISPR 15.
1.1.4 Types of power supply
Two types of power supplies are covered by this document:
a) stand alone (or end-product) power supplies
Power supplies intended for free-standing operation (individual apparatus).
This part of IEC 61204 is applicable to PSUs developed as a unit with a direct function
and sold on the market as a stand alone unit.
b) component power supplies
These can be divided into two categories:
1) component power supplies considered as equivalent to stand alone power
supplies (apparatus)
This part of IEC 61204 is applicable to this category of component PSUs. These PSUs
are considered to be apparatus with respect to their EMC requirements, for example
those PSUs intended for use in installations or sold to the general public, cases where
no further EMC tests are anticipated. This does not include PSUs sold as spares for
repair which have been tested as part of an overall equipment.
2) component power supplies intended for a professional installer
This part of IEC 61204 is applicable to this category of power supplies only as an aid
to specify relevant EMC requirements in order that various end-product standards may
be met.
These are component power supplies that are intended for incorporation into a final
product by a professional installer. These products may be sold to a professional
installer or placed on the market for specialized distribution and use. Further EMC
tests of the assembly are assumed.
1.1.5 Configurations and combinations of power supplies
1.1.5.1 Modular PSUs
A PSU with a single primary circuit or module and separate output modules forming a single
unit, synchronized or not, meets the requirements defined in this document as a single
component or apparatus type of PSU.
1.1.5.2 Power supply systems
An easily relocatable system containing several PSUs in parallel, in series or combination
with a single input connection complies with this document as a single component or
apparatus type of PSU. It is the responsibility of the system supplier to ensure EMC
compliance with this document or with a specific EMC standard of the end product.
1.1.5.3 Power supply installations
When a number of PSUs are used in an installation and are supplied by a distributed AC or
DC network, then this is a power installation. This type of arrangement is not easily
relocatable. Each individual PSU complies with this document and this is the responsibility of
the PSU manufacturer who also provides information on the correct installation of his product.
The EMC considerations of the final installation are the responsibility of the professional
installer.
– 8 – IEC 61204-3:2016 © IEC 2016
1.1.5.4 Distributed power supplies
This is a power installation where the input AC or DC supply is distributed to individual power
conversion units or modules which are installed locally to the circuitry to be supplied. This
document applies to the individual products as appropriate. The EMC performance of the
overall system or installation is the responsibility of the professional installer.
1.1.5.5 Power supplies in parallel or in series
Where PSUs are sold to be connected in parallel or in series, their documentation shall
include information relating to the expected EMC performance for such arrangements.
1.2 Object
The object of this part of IEC 61204 is to define EMC limits and test methods for PSUs. It
includes limits for electromagnetic emissions which may cause interference to other electronic
equipment (e.g. radio receivers, measuring and computer devices), as well as
electromagnetic immunity limits for continuous and transient conducted and radiated
disturbances including electrostatic discharges.
This part of IEC 61204 defines the minimum electromagnetic compatibility requirements for
PSUs.
To comply with this part of IEC 61204, no additional EMC tests are required or necessary
beyond those stated here.
2 Normative references
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.
IEC 60050-121, International Electrotechnical Vocabulary – Part 121: Electromagnetism
IEC 60050-151, International Electrotechnical Vocabulary – Part 151: Electrical and magnetic
devices
IEC 60050-161, International Electrotechnical Vocabulary – Part 161: Electromagnetic
compatibility
IEC 60050-551, International Electrotechnical Vocabulary – Part 551: Power electronics
IEC 60065, Audio, video and similar electronic apparatus – Safety requirements
IEC 60146-1-1, Semiconductor converters – General requirements and line commutated
converters – Part 1-1: Specification of basic requirements
IEC 60601-1, Medical electrical equipment – Part 1: General requirements for basic safety
and essential performance
IEC 60950-1, Information technology equipment – Safety – Part 1: General requirements
IEC 61000-3-2:2014, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for
harmonic current emissions (equipment input current ≤16 A per phase)

IEC 61000-3-3, Electromagnetic compatibility (EMC) – Part 3-3: Limits – Limitation of voltage
changes, voltage fluctuations and flicker in public low-voltage supply systems, for equipment
with rated current ≤16 A per phase and not subject to conditional connection
IEC 61000-3-12, Electromagnetic compatibility (EMC) – Part 3-12: Limits – Limits for
harmonic currents produced by equipment connected to public low-voltage systems with input
current >16 A and ≤75 A per phase
IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4-2: Testing and measurement
techniques – Electrostatic discharge immunity test
IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measurement
techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement
techniques – Electrical fast transient/burst immunity test
IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4-5: Testing and measurement
techniques – Surge immunity test
IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4-6: Testing and measurement
techniques – Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-4-8, Electromagnetic compatibility (EMC) – Part 4-8: Testing and measurement
techniques – Power frequency magnetic field immunity test
IEC 61000-4-11, Electromagnetic compatibility (EMC) – Part 4-11: Testing and measuring
techniques – Voltage dips, short interruptions and voltage variations immunity tests
IEC 61000-6-1, Electromagnetic compatibility (EMC) – Part 6-1: Generic standards –
Immunity for residential, commercial and light-industrial environments
IEC 61000-6-2, Electromagnetic compatibility (EMC) – Part 6-2: Generic standards –
Immunity for industrial environments
IEC 61000-6-3, Electromagnetic compatibility (EMC) – Part 6-3: Generic standards –
Emission standard for residential, commercial and light-industrial environments
IEC 61000-6-4, Electromagnetic compatibility (EMC) – Part 6-4: Generic standards –
Emission standard for industrial environments
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 62368-1, Audio/video, information and communication technology equipment – Part 1:
Safety requirements
CISPR 11, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
CISPR 16-1 (all parts), Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 16-1-2:2014, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 1-2: Radio disturbance and immunity measuring apparatus – Coupling
devices for conducted disturbance measurements

– 10 – IEC 61204-3:2016 © IEC 2016
CISPR 16-1-3, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1-3: Radio disturbance and immunity measuring apparatus – Ancillary
equipment – Disturbance power
CISPR 16-2-1:2014, Specification for radio disturbance and immunity measuring apparatus
and methods – Part 2-1: Methods of measurement of disturbances and immunity – Conducted
disturbance measurements
CISPR 16-2-2, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 2-2: Methods of measurement of disturbances and immunity – Measurement
of disturbance power
CISPR 16-2-3, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 2-3: Methods of measurement of disturbances and immunity – Radiated
disturbance measurements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-121,
IEC 60050-151, IEC 60050-161, IEC 60050-551, IEC 60146-1-1 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
environment
3.1.1
residential, commercial and light industrial environment
environment encompassed by the generic standard IEC 61000-6-3
Note 1 to entry: An indication of the locations included by this environment is given in Annex G.
3.1.2
industrial environment
environment encompassed by the generic standard IEC 61000-6-4
Note 1 to entry: An indication of the locations included by this environment is given in Annex G.
3.2
protection distance
distance for an electronic or electrical apparatus beyond which the interference levels shall
not impair the use of other electronic or electrical equipment, for example broadcast radio and
television receivers
3.3
distributed power system
system of localized power converters supplied from a distributed power bus
3.4
port
particular interface of a product with the external electromagnetic environment
Note 1 to entry: Examples of ports are given in Figure 1.

Enclosure port
AC input power port DC output power port

DC input power port
PSU
Signal/control line port
IEC
Figure 1 – Examples of ports
3.4.1
enclosure port
physical boundary of the PSU product through which and on which electromagnetic fields may
radiate or impinge
3.4.2
signal port
low energy level input or output port providing diagnostic or control information
3.4.3
DC input power port
external DC energy source connection point
3.4.4
DC output power port
external connection point for providing output DC energy
3.4.5
AC input power port
external AC energy source connection point
3.5
power supply
PSU
electrical or electronic device which transforms energy from an input source into a single or
multiple output energy source
3.5.1
component power supply
modular PSU
sub-unit PSU
assemblies of electrical and/or electronic devices designed to provide or modify energy
Note 1 to entry: They are intended for incorporation into end-products by a professional installer. They are not
intended for free-standing applications.
3.5.2
stand alone power supply
intended for use in laboratories, workshops and other areas in free-standing applications
Note 1 to entry: They are end-products, completely enclosed with full protection against electrostatic discharge
and contact with hazardous parts which are accessible to the end-user. Typical examples include adjustable or
fixed output bench-top units, plug-top units, free-standing and wall-mounted units.

– 12 – IEC 61204-3:2016 © IEC 2016
3.5.3
bench-top power supply
supply intended for laboratory or similar use
Note 1 to entry: They are stand alone PSUs, sometimes with monitoring and measuring facilities.
3.5.4
open card power supply
frameless PSU
printed circuit board devoid of a metal mounting bracket
Note 1 to entry: It is a component PSU intended for use by a installer.
3.5.5
open frame power supply
supply that generally uses a printed circuit board mounted on a metal bracket for attachment
to the professional installer's equipment chassis
Note 1 to entry: This bracket provides heat transfer for the cooling of power semiconductors. Optionally, a cover
may be used for safety reasons and/or to reduce radiated interference.
3.5.6
plug-in card power supply
supply intended to be plugged into a subrack
Note 1 to entry: The design may be "open-card", "open-frame" or "cased". A plug-in card PSU is generally
intended for use by a professional installer.
3.5.7
cased power supply
enclosed power supply
supply fully enclosed, cased or housed PSU
Note 1 to entry: The design uses the housing as a heat sink or employs fan(s) for forced air cooling.
3.5.8
plug-top power supply
direct plug-in power supply
power supply built into a mains voltage plug top
3.5.9
uninterruptible power supply
UPS
supply intended to provide a source of energy secure against mains failure
Note 1 to entry: This type of product would normally be free-standing.
3.6
end-product
finished unit which is designed to stand alone, useable by an end-user and having a direct
function for the end-user
Note 1 to entry: It is intended to be placed on the market and/or taken into service as a single unit or as part of a
system or installation.
3.7
system
localized group of interconnected products which is easily relocatable
Note 1 to entry: Typical examples of this would be a computer, including mouse, keyboard, printer and monitor, or
a hi-fi system, TV and video recorder.

3.8
installation
collection of interconnected products which is not easily relocatable
Note 1 to entry: Typical examples of this include an industrial process installation or a power plant control
installation.
3.9
professional installer
technically competent person or organization capable of correctly assembling/installing
components and subassemblies into an end-product, or end-products into a system or
installation, and, in so doing, fully complying with the technical and legal requirements of the
end-product, system or installation
3.10
full rated load
maximum continuous or average power a product is marked to supply
3.11
mains supply
3.11.1
industrial mains supply
source of electrical energy provided solely for industrial use
3.11.2
private mains supply
localized source of electrical energy (e.g. generator or UPS) which is not directly connected to
the public network
3.11.3
public mains supply
source of electrical energy provided for general public use in domestic, commercial or light
industrial environments
3.12
critical frequency of a PSU
the frequency, the wavelength of which is equal to four times the longest side length of the
PSU
3.13
residual voltage
minimum value of RMS voltage recorded during a voltage dip or short
interruption
Note 1 to entry: The residual voltage may be expressed as a value in volts, or as a percentage or per unit value
relative to the reference voltage.
3.14
type test
conformity test made on one or more items representative of the production
[SOURCE: IEC 60050-151:2001, 151-16-16]
4 Applicability of tests to different PSU technologies
Guidance on this issue is given in Annex A.

– 14 – IEC 61204-3:2016 © IEC 2016
5 General requirements and test conditions
5.1 General requirements
The manufacturer of the PSU has a responsibility to provide information relating to the EMC
performance, application, intended environment and installation guidelines for the product.
5.2 Test conditions
The tests shall be performed using the manufacturer’s recommended wiring and installation
instructions. There will be no connections other than those specified by the manufacturer.
The configuration, orientation and electrical test conditions of the PSU shall be representative
of the worst case in-service conditions. Otherwise, all measurements shall be performed at
rated nominal input voltage, full rated load and ambient temperature between 15 °C and
35 °C. The PSU shall be at its normal operating temperature.
The load is presumed not to generate any electromagnetic disturbance. Load resistors may be
cooled by a fan or cooling fluid.
All tests specified in this document are type tests only.
A PSU device is deemed to fulfill the requirements specified in this document if it complies
with the defined functional and performance requirements using the test methods specified in
this document.
Precautions shall be taken against the EUT (equipment under test) becoming dangerous or
unsafe as a result of the immunity tests specified in this document.
6 Emission requirements
6.1 General
If the cable arrangements of the application are known, then those shall be used. If they are
not known, the arrangements shall be chosen in accordance with 6.3 and 6.4. The cable
arrangement implemented during the test shall be stated in the documentation.
6.2 Low frequency phenomena (f ≤ 9 kHz; AC input only)
6.2.1 Commutation notches
In this subclause, only PSUs with commutation of the primary current are covered. PSUs of
high power designed as line commutated converters may cause notches if connected to a
high impedance source. Measurements or calculations are not mandatory. Information and
recommendations are given in Annex B.
6.2.2 Current harmonics and interharmonics
The limits for PSUs connected to a public mains supply up to and including a rated input
current of 16 A are given in IEC 61000-3-2. This requirement is applicable to apparatus and
components considered as apparatus covered within the scope of IEC 61000-3-2.
NOTE Limits for harmonic currents produced by equipment connected to public low-voltage systems with input
current >16 A and ≤75 A per phase are given in IEC 61000-3-12.
Harmonic measurements, especially on PSUs, are sensitive to the voltage source. In many
cases, the public mains supply may not be a suitable source for this purpose.

Therefore, one of the following methods shall be used.
a) Using a public mains supply in accordance with the related standard IEC 61000-3-2 or
IEC 61000-3-12:
– the limits for the harmonics of the voltage source shall be met with the PSU operating
at full rated load.
b) Using an artificial supply in accordance with the related standard IEC 61000-3-2 or
IEC 61000-3-12.
c) Calculation or simulation in accordance with the related standard IEC 61000-3-12:
– usage of the voltage source as an ideal sine wave;
– notice the worst case internal impedance of the PSU i
...