EN 61204-3:2000

SLOVENSKI SIST EN 61204-3:2002
prva izdaja
STANDARD
marec 2002
Low-voltage power supplies, d.c. output – Part 3: Electromagnetic compatibility
(EMC) (IEC 61204-3:2000)
ICS 5HIHUHQþQDãWHYLOND
29.200; 33.100.01
! "#$%!&!%’()*#+’
EUROPEAN STANDARD EN 61204-3
NORME EUROPÉENNE
EUROPÄISCHE NORM December 2000

ICS 29.200;33.100
English version
Low voltage power supplies, d.c. output
Part 3: Electromagnetic compatibility (EMC)
(IEC 61204-3:2000)
Alimentations basse tension,  Stromversorgungsgeräte für
sortie continue Niederspannung mit Gleichstromausgang
Partie 3: Compatibilité électromagnétique Teil 3: Elektromagnetische Verträglichkeit
(CEM) (EMV)
(CEI 61204-3:2000) (IEC 61204-3:2000)

This European Standard was approved by CENELEC on 2000-11-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway,
Portugal, Spain, Sweden, Switzerland and United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2000 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 61204-3:2000 E
Page 2
Foreword
The text of document 22E/75/FDIS, future edition 1 of IEC 61204-3, prepared by SC 22E, Stabilized
power supplies, of IEC TC 22, Power electronics, was submitted to the IEC-CENELEC parallel vote and
was approved by CENELEC as EN 61204-3 on 2000-11-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2001-08-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2003-11-01

Annexes designated "normative" are part of the body of the standard.
Annexes designated "informative" are given for information only.
In this standard, annexes A, F and ZA are normative and annexes B, C, D, E, G, H and I are informative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61204-3:2000 was approved by CENELEC as a European
Standard without any modification.
__________
Page 3
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other publications.
These normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this European Standard only when incorporated in it by amendment or revision. For undated
references the latest edition of the publication referred to applies (including amendments).
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
IEC 60050-121 1998 International Electrotechnical Vocabulary - -
Part 121: Electromagnetism
IEC 60050-131 1978 Chapter 131: Electric and magnetic circuits - -

IEC 60050-151 1978 Chapter 151: Electrical and magnetic - -
devices
IEC 60050-161 1990 Chapter 161: Electromagnetic compatibility - -

IEC 60050-551 1998 Part 551: Power electronics - -

IEC 60146-1-1 1991 Semiconductor convertors - General EN 60146-1-1 1993
requirements and line commutated
convertors
Part 1-1: Specifications of basic
requirements
IEC 60664-1 (mod) 1992 Insulation coordination for equipment within HD 625.1 S1 1996
low-voltage systems + corr. November 1996
Part 1: Principles, requirements and tests

IEC 61204 (mod) 1993 Low-voltage power supply devices, d.c. EN 61204 1995
output - Performance characteristics and
safety requirements
IEC 61000-3-2 2000 Electromagnetic compatibility (EMC) EN 61000-3-2 2000
(mod) Part 3-2: Limits - Limits for harmonic current
emissions (equipment input current up to
and including 16 A per phase)
IEC 61000-3-3 1994 Part 3-3: Limits - Limitation of voltage EN 61000-3-3 1995
fluctuations and flicker in low-voltage supply + corr. July 1997
systems for equipment with rated current up
to and including 16 A
IEC 61000-4-2 1995 Part 4-2: Testing and measurement EN 61000-4-2 1995
techniques - Electrostatic discharge
immunity test
A1 1998  A1 1998
Page 4
Publication Year Title EN/HD Year
IEC 61000-4-3 1995 Part 4-3: Testing and measurement EN 61000-4-3 1996
(mod) techniques - Radiated, radio-frequency,
electromagnetic field immunity test

IEC 61000-4-4 1995 Part 4-4: Testing and measurement EN 61000-4-4 1995
techniques - Electrical fast transient/burst
immunity test
IEC 61000-4-5 1995 Part 4-5: Testing and measurement EN 61000-4-5 1995
techniques - Surge immunity test

IEC 61000-4-6 1996 Part 4-6: Testing and measurement EN 61000-4-6 1996
techniques - Immunity to conducted
disturbances, induced by radio-frequency
fields
IEC 61000-4-11 1994 Part 4-11: Testing and measurement EN 61000-4-11 1994
techniques - Voltage dips, short
interruptions and voltage variations
immunity tests
CISPR 11 (mod) 1997 Industrial, scientific and medical (ISM) EN 55011 1998
radio-frequency equipment - Radio
disturbance characteristics - Limits and
methods of measurement
CISPR 14-1 2000 Electromagnetic compatibility - EN 55014-1 2000
Requirements for household appliances,
electric tools and similar apparatus
Part 1: Emission
CISPR 16-1 1999 Specification for radio disturbance and - -
immunity measuring apparatus and
methods
Part 1: Radio disturbance and immunity
measuring apparatus
CISPR 22 (mod) 1997 Information technology equipment - Radio EN 55022 1998
disturbance characteristics - Limits and + corr. August 1999
methods of measurement
ISO/IEC Guide 25 1990 General requirements for the competence - -
of calibration and testing laboratories

NORME CEI
INTERNATIONALE IEC
61204-3
INTERNATIONAL
Première édition
STANDARD
First edition
2000-11
Alimentations basse tension, sortie continue –
Partie 3:
Compatibilité électromagnétique (CEM)
Low-voltage power supplies, d.c. output –
Part 3:
Electromagnetic compatibility (EMC)
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61204-3  IEC:2000 – 3 –
CONTENTS
Page
FOREWORD . 7
Clause
1 Scope and object . 11
2 Normative references . 13
3 Terms and definitions. 17
4 Applicability of tests to different PSU technologies. 23
5 General requirements and test conditions . 25
5.1 General requirements. 25
5.2 Test conditions. 25
6 Emission requirements . 25
6.1 Limits in defined environments . 25
6.2 Low frequency phenomena (f < 9 kHz; a.c. input only) . 29
6.3 High frequency conducted phenomena . 31
6.4 High frequency radiated phenomena . 31
7 Immunity requirements . 35
7.1 Performance criteria. 35
7.2 Basic immunity requirements, high frequency disturbances. 37
8 Configurations and combinations of power supplies . 47
8.1 Modular PSUs. 47
8.2 Power supply systems. 47
8.3 Power supply installations . 47
8.4 Distributed power supplies . 47
8.5 Power supplies in parallel or in series. 47
9 Power supply families. 47
10 Statistical aspects . 49
11 Safety aspects . 49
12 Test report . 49
Annex A (normative) Guidelines on the classification of PSUs . 51
Annex B (informative) Commutation notches. 55
Annex C (informative) Calculation and simulation of the input current harmonics . 57
Annex D (informative) Special consideration for d.c. inputs . 59
Annex E (informative) Critical frequency for high frequency power measurement. 65
Annex F (normative) Guidelines on power supply families . 67
Annex G (informative) Summary of classification of environments and limits . 71
Annex H (informative) Emission Limits . 73
Annex I (informative) Explanatory remark for applying criterion B for continuous
disturbance phenomena (see 7.1) . 75

61204-3  IEC:2000 – 5 –
Page
Figure 1 – Test set-up for the measurement of disturbance power. 35
Table 1 – Applicability of tests . 23
Table 2 – Criteria to prove the performance of a PSU against EM disturbances . 37
Table 3 – Immunity – Enclosure port . 39
Table 4 – Immunity – Ports for signal lines and control lines. 39
Table 5 – Immunity – DC input and output power ports. 41
Table 6 – Immunity – AC input power ports . 41
Table 7 – Immunity – Enclosure port . 43
Table 8 – Immunity – Ports for signal lines and control lines. 43
Table 9 – Immunity – DC input and output power ports. 45
Table 10 – Immunity – AC input power ports . 45
Table A.1 – Classification of power supplies and the relevant EMC standards . 53
Table D.1 – Immunity – DC input power ports – Input category a). 61
Table D.2 – Immunity – DC input power ports – Input category b). 61
Table D.3 – Immunity – Enclosure port – Input categories a and b. 63
Table G.1 – Summarized classification of environments and limits . 71
Table H.1 – Limits of mains terminal disturbance voltage (a.c. input port). 73
Table H.2 – Limits for electromagnetic radiation/interference power disturbance
(all field strength limits refer to quasi-peak measurements) . 73

61204-3  IEC:2000 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW VOLTAGE POWER SUPPLIES, DC OUTPUT –
Part 3: Electromagnetic compatibility (EMC)
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The 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 electronics.
International Standard IEC 61204-3 has been prepared by subcommittee 22E: Stabilized power
supplies, of IEC technical committee 22: Power electronics.
IEC 61204-3 cancels and replaces IEC 60478-3 published in 1989.
IEC 61204-3 has the status of a product standard.
The text of this standard is based on the following documents:
FDIS Report on voting
22E/75/FDIS 22E/78/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with ISO/IEC Directives, Part 3.
Annexes A and F form an integral part of this standard.
Annexes B, C, D, E, G, H and I are for information only.
The contents of the corrigendum of December 2000 have been included in this copy.

61204-3  IEC:2000 – 9 –
IEC 61204 consists of the following parts, under the general title: Low voltage power supplies,
d.c. output
1)
Part 1: Terms and definitions
1)
Part 2: Performance characteristics
Part 3: Electromagnetic compatibility (EMC)
1)
Part 4: Tests other than EMC
1)
Part 5: Measurement of the magnetic component of the reactive near field
2)
Part 6: Requirements for low-voltage power supplies of assessed performance
1)
Part 7: Safety requirements
The committee has decided that the contents of this publication will remain unchanged until
2006. At this date, the publication will be
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
___________
1)
Under consideration.
2)
To be published.
61204-3  IEC:2000 – 11 –
LOW VOLTAGE POWER SUPPLIES, DC OUTPUT –
Part 3: Electromagnetic compatibility (EMC)
1 Scope and object
This part of IEC 61204 specifies electromagnetic compatibility (EMC) requirements for power
supply units (PSUs) providing d.c. output(s) up to 200 V at a power level of up to 30 kW,
operating from a.c. or d.c. source voltages of up to 600 V.
The devices are for free-standing operation or for use in other equipment when used with
adequate electrical and mechanical protection.
For certain specialized industrial PSUs, for example in the chemical and metallurgical industry,
other product EMC standards may exist. In this case these standards can be used as an
alternative.
Since many PSUs are used as components of larger units which are covered by different EMC
standards, a classification of power supplies and the applicability of the relevant EMC
standards is given in items a) and b) below. Further guidelines on classification are given in
annex A.
a) 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 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 assembler/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 assembler. These products may be sold to a professional
assembler 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).
61204-3  IEC:2000 – 13 –
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 normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 61204. For dated references, subsequent amendments
to, or revisions of, any of these publications do not apply. However, parties to agreements
based on this part of IEC 61204 are encouraged to investigate the possibility of applying the
most recent editions of the normative documents indicated below. For undated references, the
latest edition of the normative document referred to applies. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60050-121, International Electrotechnical Vocabulary (IEV) – Part 121: Electromagnetism
IEC 60051(131), International Electrotechnical Vocabulary (IEV) – Chapter 131: Electric and
magnetic circuits
IEC 60050(151), International Electrotechnical Vocabulary (IEV) – Chapter 151: Electrical and
magnetic devices
IEC 60050(161), International Electrotechnical Vocabulary (IEV) – Chapter 161: Electro-
magnetic compatibility
IEC 60050-551, International Electrotechnical Vocabulary (IEV) – Part 551: Power electronics
IEC 60146-1-1, Semiconductor convertors – General requirements and line commutated
convertors – Part 1-1: Specifications of basic requirements
IEC 60664-1, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements, tests
IEC 61204, Low-voltage power supply devices, d.c. output – Performance characteristics and
safety requirements (future IEC 61204-2)
IEC 61000-3-2, Electromagnetic compatibility (EMC) – Part 3: Limits – Section 2: Limits for
*
harmonic current emissions (equipment input current ≤16 A per phase)
___________
*
There is a consolidated edition 1.2 (1998) that includes IEC 61000-3-2 (1995), and its amendment 1 (1997) and
its amendment 2 (1998).
61204-3  IEC:2000 – 15 –
IEC 61000-3-3, Electromagnetic compatibility (EMC) – Part 3: Limits – Section 3: Limitation of
voltage fluctuations and flicker in low-voltage supply systems for equipment with rated current
≤16A
IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
*
techniques – Section 2: – Electrostatic discharge immunity test. Basic EMC Publication
Amendment 1 (1998)
IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
**
techniques – Section 3: Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
techniques – Section 4: Electrical fast transient/burst immunity test. Basic EMC Publication
IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
techniques – Section 5: Surge immunity test
IEC 61000-4-6, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement
techniques – Section 6: Immunity to conducted disturbances, induced by radio-frequency fields
IEC 61000-4-11, Electromagnetic compatibility (EMC) – Part 4: Testing and measuring
techniques – Section 11: Voltage dips, short interruptions and voltage variations immunity tests
CISPR 11, Industrial, scientific and medical (ISM) radio-frequency equipment – Electro-
***
magnetic disturbance characteristics – Limits and methods of measurement
CISPR 14-1, Electromagnetic compatibility – Requirements for household appliances, electric
tools and similar apparatus – Part 1: Emission – Product family standard
CISPR 16-1, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1: Radio disturbance and immunity measuring apparatus
CISPR 22, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement
ISO/IEC Guide 25, General requirements for the competence of calibration and testing
laboratories
___________
*
There is a consolidated edition 1.1 (1999) that includes IEC 61000-4-2 (1995) and its amendment 1 (1998).
**
There is a consolidated edition 1.1 (1998) that includes IEC 61000-4-3 (1995) and its amendment 1 (1998).
***
There is a consolidated edition 3.1 (1999) that includes CISPR 11 (1997) and its amendment 1 (1999).

61204-3  IEC:2000 – 17 –
3 Terms and definitions
For the purpose of this part of IEC 61204, the definitions given in IEC 60050-121,
IEC 60050(151), IEC 60050(161), IEC 60050-551 and IEC 60146-1-1, as well as the following
definitions apply.
3.1
environment
3.1.1
residential environment
all domestic establishments which are directly connected to a low voltage public mains supply.
The “protection distance” is 10 m, reflecting apartment size
3.1.2
commercial and light industrial environment
commercial and light industrial establishments which may or may not be connected to a low
voltage public mains supply. The “protection distance” can be 10 m or 30 m depending on
where the use of broadcast radio and television receivers may be expected
3.1.3
industrial environment
industrial establishments which are not connected to the low voltage public mains supply. The
“protection distance” is 30 m, owing to larger premises
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.
[IEV 131-02-21 modified]
Examples of ports:
Enclosure port
AC input power port DC output power port
DC input power port
PSU
Earth port Signal / control line port

61204-3  IEC:2000 – 19 –
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 or control line port
low energy level input or output port providing diagnostic or control information
3.4.3
d.c. input power port
external d.c. energy source connection point
3.4.4
d.c. output power port
external connection point for providing output d.c. energy
3.4.5
a.c. input power port
external a.c. energy source connection point
3.5
power supply (PSU)
an 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. They
are intended for incorporation into end-products by a professional assembler/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. 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
intended for laboratory or similar use. 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. It is a component PSU intended for
use by a professional assembler

61204-3  IEC:2000 – 21 –
3.5.5
open frame power supply
generally uses a printed circuit board mounted on a metal bracket for attachment to the
professional assembler's equipment chassis. 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
intended to be plugged into a subrack. The design may be "open-card", "open-frame" or
"cased". A plug-in card PSU is generally intended for use by a professional assembler
3.5.7
enclosed/cased power supply
fully enclosed/cased/housed PSU. The design uses the housing as a heat sink or employs
fan(s) for forced air cooling
3.5.8
plug-top (direct plug-in) power supply
power supply built into a mains voltage plug top
3.5.9
uninterruptible power supply (UPS)
intended to provide a source of energy secure against mains failure. 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. 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. 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. 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
3.10
professional assembler/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

61204-3  IEC:2000 – 23 –
3.11
full rated load
maximum continuous or average power a product is marked to supply
3.12 mains supply
3.12.1
industrial mains supply
source of electrical energy provided solely for industrial use
3.12.2
private mains supply
localized source of electrical energy (e.g. generator or UPS) which is not directly connected to
the public network
3.12.3
public mains supply
source of electrical energy provided for general public use in domestic, commercial or light
industrial environments
3.13
critical frequency of a PSU
The frequency, the wavelength of which is equal to four times the longest side length of the
PSU
4 Applicability of tests to different PSU technologies
PSUs differ greatly in their technology; it is neither reasonable nor necessary to apply all EMC
tests to all PSU technologies.
The following table is applicable to free-standing PSUs and component PSUs considered as
equivalent to apparatus (see also annex A).
In the case of component PSUs intended for a professional installer, this table is provided as a
guide.
Table 1 – Applicability of tests
Clause or subclause
Emission Immunity
Group Technology Remarks
6.2 6.3 6.4 7
Modules with pin or screw NA R R R These are component power
I
connections for use on supplies
PCBs
II AC/DC rectifier-filtered or M M NA NA If only rectifier disturbances
Ferro-resonant PSU
III AC/DC linear controlled M M NA M No switching (note)
PSU
IV DC/DC converters, battery NA R M M No primary rectifier, no direct
or rectifier powered connection to a.c. supply
V AC/DC PSUs not covered MM M M
by I, II, III or IV
NOTE When products or system are within the scope of CISPR 14-1, the incorporated group III PSUs may be
tested according to CISPR 14-1.
M = Mandatory.
R = Recommended.
NA = No measurement.
61204-3  IEC:2000 – 25 –
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. Load resistors may be
cooled by a fan or cooling fluid.
All tests specified in this standard 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.
Precautions shall be taken against the equipment under test becoming dangerous or unsafe as
a result of the immunity tests specified in this standard.
6 Emission requirements
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 shall be stated in the documentation.
6.1 Limits in defined environments
The environments in which a PSU may be installed are classified as follows:
Residential environment
Examples of typical locations are:
– residential properties, for example houses, apartments, etc.;
Commercial and light industrial environment
Examples of typical locations are:
– retail outlets, for example shops, supermarkets, etc.;
– business premises, for example offices, banks, etc.;
– establishments of public entertainment, for example cinemas, public bars, dance halls, etc.;
– outdoor locations, for example petrol stations, car parks, amusement and sports centres, etc.;
– light-industrial locations, for example workshops, laboratories, service centres, etc.

61204-3  IEC:2000 – 27 –
Industrial environment
The limits for the above-mentioned environments are given below and a summary is given in
annex G.
6.1.1 Class B limits
PSUs which meet class B limits are defined as class B equipment. They are intended to be
installed in a residential environment.
Class B limits are also required for PSUs installed in a commercial or light industrial
environment when the equipment is directly connected to a public mains supply interconnected
with a residential environment.
6.1.2 Class A limits
PSUs which meet class A limits are defined as class A equipment. They are intended to be
installed in a commercial, light industrial or industrial environment where the equipment is not
directly connected to a public mains supply interconnected with a residential environment.
Class A equipment shall carry the following remark in its documentation:
Warning: This is a class A product. In a residential, commercial or light industrial
environment it may cause radio interference. This product is not intended to be installed
in a residential environment; in a commercial and light industrial environment with
connection to the public mains supply, the user may be required to take adequate
measures to reduce interference.
The user, advised by the supplier, is responsible for the electromagnetic compatibility of the
installed product in his environment.
6.1.3 Special applications
This concerns the industrial environment only where equipment with high input current (>25 A)
is connected to an industrial mains supply, or a private mains supply, and where the protection
distance is >100 m.
Limits are under consideration.
In these applications, clear warning of the restricted use of the equipment shall be given in the
documentation supplied with it.
Examples:
– internal radio interference tolerated by the user and external interference within acceptable
limits (e.g. mains supply independent of public mains supply);
– safety requirements in conflict with EMC requirements in high power installations.

61204-3  IEC:2000 – 29 –
6.2 Low frequency phenomena (f ≤ 9 kHz; a.c. 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, but it is not
mandatory for PSUs used in countries where there are no regulations requiring product
harmonic limits.
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 IEC 61000-3-2.
– 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 IEC 61000-3-2.
c) Calculation or simulation if it takes into account:
– the voltage source as an ideal sine wave;
– 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 conditions
which cannot be taken into account in this standard; this system aspect is the responsibility of
the user, installer or assembler.
6.2.3 Voltage fluctuations and flicker
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 61000-3-3. This requirement is applicable to apparatus and
components considered as apparatus covered within the scope of IEC 61000-3-3, but it is not
mandatory for PSUs used in countries where there are no regulations requiring voltage
fluctuations and flicker limits.
For PSUs, only measurements or calculations for d (maximum relative voltage change) are
max
necessary.
NOTE It is recommended to measure the amplitude and the duration of the inrush current and to calculate the
r.m.s. value in the first period after switching-on. Most PSUs have inrush current less than 10 ms which means that
high inrush currents are still below the d limit.
max
61204-3  IEC:2000 – 31 –
Fluctuations of the PSU input current may be caused by a time varying load on the PSU. This
system aspect is the responsibility of the user, installer or assembler.
6.3 High frequency conducted phenomena
6.3.1 High frequency line conducted phenomena
The tests of conducted emission shall be performed in accordance with CISPR 22, or
CISPR 11 in the case of industrial applications. However, CISPR 22 is not precluded from use
for industrial applications.
Limits are listed in annex H, Table H.1
For d.c. input, see annex D.
6.3.2 High frequency conducted phenomena for d.c. output power ports
This standard does not define limits for load terminal disturbance voltage for high frequency
conducted phenomena on d.c. output ports.
In some cases, manufacturer and user may need to agree on limits.
NOTE The manufacturer is recommended to give application advice in the documentation as to how to avoid
feedback from the load cables to the mains.
6.4 High frequency radiated phenomena
The radiation test can be made with an antenna according to CISPR 22, or with the absorbing
clamp method according to CISPR 16-1 with the restrictions stated in 6.4.3.
The manufacturer must justify the choice of the interference power measurement in the
documentation and test report, in case of dispute the test method of the manufacturer applies.
Limits are listed in annex H, table H.2.
6.4.1 Tests with an antenna
The tests of radiation disturbance shall be performed in accordance with CISPR 22.
Load cables of unknown length shall be arranged horizontally, equally separated from each
other and shall be 1 m in length.
The mains cable is arranged 1 m horizontally and then 0,8 m vertically to the ground where it is
connected to the power source. Cables are unshielded, unless the PSU is supplied with a
shielded cable.
Any other arrangement shall be justified and explained in the documentation.
The distance between the antenna and the PSU shall be 10 m if the limits of table H.2 in
annex H are applied.
At a measuring distance of 30 m, the limits are reduced by 10 dB.
At a measuring distance of 3 m, the limits are increased by 10 dB.

61204-3  IEC:2000 – 33 –
6.4.2 Test with clamp method
The measuring receiver shall have a quasi-peak detector and shall be in accordance with the
requirements of CISPR 16-1. The absorbing clamp shall be designed and calibrated in accord-
ance with CISPR 16-1.
NOTE The clamps generally refer to a 10 m radiated field measurement.
For measurement set-up and procedure, see figure 1.
The PSU and the cable to be tested shall be placed on a non-metallic support of 0,8 m height
and at least 0,8 m from all other metallic objects.
The cable under test is stretched in a straight line over a length of at least 5 m on a non-
metallic support allowing the absorbing clamp to be moved along the cable under test. The
clamp shall be placed around the cable in the correct orientation (current sensor on the side of
the PSU).
All other cables are either disconnected (if the correct operation of the equipment can be
maintained without the cables), or equipped with absorbing ferrite tubes (clamps) close to the
PSU.
Each cable of the PSU shall be tested in turn. Cables which are longer than 5 m are tested as
described above with 5 m of cable in the test set-up. The layout of the excess cable is not
critical.
Cables which, in normal application, are restricted in length to less than 5 m are tested as
follows:
Cables with a restricted length
– ≤ 0,25 m are not measured at all;
– < s are lengthened to s;
– > s are measured over the total length.
where s is twice the length of the clamp.
The clamp shall be displaced along the cable under test, starting closest to the PSU up to a
maximum of 5 m. The maximum reading is converted into disturbance power, using the clamp
calibration factor. The displacement needed is from zero to a half-wavelength of the measured
frequency. All maxima sh
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