IEC 61000-1-2:2016

IEC 61000-1-2 ®
Edition 1.0 2016-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Electromagnetic compatibility (EMC) –
Part 1-2: General – Methodology for the achievement of functional safety of
electrical and electronic systems including equipment with regard to
electromagnetic phenomena
Compatibilité électromagnétique (CEM) –
Partie 1-2: Généralités – Méthodologie pour la réalisation de la sécurité
fonctionnelle des systèmes électriques et électroniques, y compris les
équipements, du point de vue des phénomènes électromagnétiques

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IEC 61000-1-2 ®
Edition 1.0 2016-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ

Electromagnetic compatibility (EMC) –

Part 1-2: General – Methodology for the achievement of functional safety of

electrical and electronic systems including equipment with regard to

electromagnetic phenomena
Compatibilité électromagnétique (CEM) –

Partie 1-2: Généralités – Méthodologie pour la réalisation de la sécurité

fonctionnelle des systèmes électriques et électroniques, y compris les

équipements, du point de vue des phénomènes électromagnétiques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.100.99 ISBN 978-2-8322-3304-7

– 2 – IEC 61000-1-2:2016 © IEC 2016
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
Particular considerations for IEC 61000-1-2. 7
1 Scope . 8
2 Normative references. 9
3 Terms, definitions and abbreviations . 9
3.1 Terms and definitions . 9
3.2 Abbreviations . 14
4 General considerations . 15
4.1 General . 15
4.2 Considerations with regard to electromagnetic phenomena . 18
5 Achievement of functional safety . 19
5.1 General . 19
5.2 Safety lifecycle . 20
5.3 Safety integrity . 20
5.4 Specific steps for the achievement of functional safety with regard to
electromagnetic disturbances . 21
5.5 Management of EMC for functional safety . 21
5.5.1 General . 21
5.5.2 Management of functional safety performance with respect to
electromagnetic phenomena at system level . 21
5.5.3 Management of functional safety performance with respect to
electromagnetic phenomena at element supplier level . 22
6 Electromagnetic environment . 23
6.1 General . 23
6.2 Electromagnetic environment information . 24
6.3 Methodology to assess the electromagnetic environment . 25
6.4 Deriving test levels and methods . 25
7 EMC aspects of the design and integration process . 26
7.1 General . 26
7.2 EMC aspects on system level . 27
7.3 EMC aspects on equipment level . 28
8 Verification and validation of functional safety performance in respect of
electromagnetic disturbances . 29
8.1 Verification and validation processes . 29
8.2 Verification . 31
8.3 Validation . 31
8.4 Test philosophy for equipment intended for use in safety-related systems . 32
8.4.1 General . 32
8.4.2 Performance criterion DS for safety applications . 32
8.4.3 Application of the performance criterion DS . 32
8.4.4 Relationship to “normal” EMC standards . 33
8.5 Test philosophy for safety-related systems . 33
9 EMC testing with regard to functional safety . 34
9.1 Electromagnetic test types and electromagnetic test levels with regard to
functional safety . 34

9.1.1 Considerations on testing . 34
9.1.2 Types of immunity tests . 34
9.1.3 Testing levels. 34
9.2 Determination of test methods with regard to functional safety . 35
9.3 Considerations on test methods and test performance with regard to
systematic capability . 36
9.3.1 General . 36
9.3.2 Testing period . 37
9.3.3 Number of tests with different test set-ups or test samples . 37
9.3.4 Variation of test settings . 38
9.3.5 Environmental factors . 38
9.4 Testing uncertainty . 39
10 Documentation . 39
Annex A (informative) Selection of electromagnetic phenomena . 40
Annex B (informative) Measures and techniques for the achievement of functional
safety with regard to electromagnetic disturbances . 43
B.1 General principles . 43
B.2 Choosing design techniques and measures . 44
B.2.1 Introduction to design techniques and measures against
electromagnetic disturbances . 44
B.2.2 Some further details on the design techniques and measures . 53
Annex C (informative) Information concerning performance criteria and test methods . 57
Annex D (informative) Considerations on the relationship between safety-related
system, element, equipment and product, and their specifications . 59
D.1 Relationships between the terms: Safety-related system, element,
equipment and product . 59
D.2 Relationship between electromagnetic mitigation and electromagnetic
specifications . 60
D.2.1 E/E/PE system safety requirements specification . 60
D.2.2 Equipment requirements specification . 60
D.2.3 Product specifications . 60
D.2.4 Overview of the relationships between the SSRS, the various ERSs,
and product specifications . 60
Annex E (informative) Considerations on electromagnetic phenomena and safety
integrity level . 62
Annex F (informative) EMC safety planning . 65
F.1 Basic structure . 65
F.2 Requirements . 66
F.3 System/equipment data . 66
F.4 EMC matrix . 66
F.5 Analysis/assessment . 66
F.6 Measures/provisions . 66
F.7 Validation/verification . 67
Bibliography . 68

Figure 1 – Relationship between IEC 61000-1-2 and the simplified safety lifecycle as
per IEC 61508 . 17
Figure 2 – Basic approach to achieve functional safety only with regard to
electromagnetic phenomena . 19
Figure 3 – EMC between equipment M and equipment P . 27

– 4 – IEC 61000-1-2:2016 © IEC 2016
Figure 4 – Example V representation of the lifecycles demonstrating the role of
validation and verification for functional safety performance in respect of
electromagnetic disturbances . 30
Figure B 1 –General principles recommended for design to achieve electromagnetic
resilience for a complete safety-related system (where the "rugged high-specification
electromagnetic mitigation approach" is not used) . 46
Figure C.1 – Allowed effects during immunity tests . 57
Figure C.2 – Example of performance of tests after reaction of EUT . 58
Figure D.1 – Relationships between the safety-related system, equipment and products . 59
Figure D.2 – The process of achieving the electromagnetic specification in the SSRS,
using commercially available products . 61
Figure E.1 – Example of emission, immunity and compatibility levels . 62
Figure F.1 – EMC safety planning for safety-related systems . 65

Table 1 – E/E/PE system safety requirements specification, interfaces and
responsibilities according to IEC 61508 . 16
Table 2 – Overview of electromagnetic phenomena . 23
Table 3 – Design, design management techniques and other measures . 28
Table 4 – Applicable performance criteria and observed behaviour during test of
equipment intended for use in safety-related systems . 33
Table 5 – Examples for methods to increase level of confidence . 37
Table A 1 – Example of selection of electromagnetic phenomena for functional safety
in industrial environments . 40
Table B.1 – Overview of lifecycle techniques and measure recommendations for the
achievement of functional safety with regard to electromagnetic disturbances . 44
Table B.2 – Overview of techniques and measures that may be used for the
achievement of functional safety with regard to electromagnetic disturbances . 47
Table B.3 – Additional system design techniques and measures that may provide
evidence of the achievement of functional safety with regard to electromagnetic
disturbances . 50

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 1-2: General – Methodology for the achievement of functional safety
of electrical and electronic systems including equipment with regard to
electromagnetic phenomena
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) 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 61000-1-2 has been prepared by technical committee 77:
Electromagnetic compatibility.
It has the status of a basic safety publication in accordance with IEC Guide 104.
This first edition cancels and replaces the second edition of IEC TS 61000-1-2 published in
2008. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• Alignment with the changes done in the latest edition of the functional safety standard
IEC 61508.
– 6 – IEC 61000-1-2:2016 © IEC 2016
• Complete review with regard to transforming this document into an International Standard
(instead of the previous edition as Technical Specification).
• New structure of Annex B.
The text of this standard is based on the following documents:
FDIS Report on voting
77/513/FDIS 77/519/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 the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61000 series, published under the general title Electromagnetic
compatibility (EMC), can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site 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 document using a
colour printer.
INTRODUCTION
IEC 61000 is published in separate parts according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits (insofar as they do not fall under the responsibility of the product committees)
Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous
Each part is further subdivided into several parts, published either as international standards,
technical specifications or technical reports, some of which have already been published as
sections. Others will be published with the part number followed by a dash and completed by
a second number identifying the subdivision (example: IEC 61000-3-11).
Particular considerations for IEC 61000-1-2
The aim of this international standard with regard to EMC and functional safety is to address
the possible effects of electromagnetic disturbances on safety-related systems and to specify
requirements for the relevant phases of the lifecycle of a safety-related system. The objective
is to achieve the systematic capability as specified in the electrical/electronic/programmable
electronic system safety requirements specification with regard to electromagnetic aspects.
This document makes use of existing relevant basic IEC standards, as far as appropriate. It
considers the work of SC 65A relating to functional safety concepts of the IEC 61508 series
and of TC 77 and its subcommittees relating to the electromagnetic environments. More
details can be found in the publications of these committees.

– 8 – IEC 61000-1-2:2016 © IEC 2016
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 1-2: General – Methodology for the achievement of functional safety
of electrical and electronic systems including equipment with regard to
electromagnetic phenomena
1 Scope
This part of IEC 61000 establishes a methodology for the achievement of functional safety
only with regard to electromagnetic phenomena. This methodology includes the implication it
has on equipment used in such systems and installations.
This standard:
a) applies to safety-related systems and installations incorporating
electrical/electronic/programmable electronic equipment as installed and used under
operational conditions;
b) considers the influence of the electromagnetic environment on safety-related systems;
c) is not concerned with direct hazards from electromagnetic fields on living beings nor is it
concerned with safety related to breakdown of insulation or other mechanisms by which
persons can be exposed to electrical hazards.
It mainly covers EMC related aspects of the design and application specific phases of safety-
related systems and equipment used therein, and deals in particular with
• some basic concepts in the area of functional safety,
• the various EMC specific steps for the achievement and management of functional safety,
• the description and assessment of the electromagnetic environment,
• the EMC aspects of the design and integration process, taking into account the process of
EMC safety planning on system as well as on equipment level,
• the validation and verification processes regarding the immunity against electromagnetic
disturbances,
• the performance criterion and some test philosophy considerations for safety-related
systems and the equipment used therein,
• aspects related to testing of the immunity of safety-related systems and equipment used
therein against electromagnetic disturbances.
This International Standard is applicable to electrical/electronic/programmable electronic
(E/E/PE) safety-related systems intended to comply with the requirements of IEC 61508
and/or associated sector-specific functional safety standards. It is intended for designers,
manufacturers, installers and users of safety-related systems and can be used as a guide by
IEC committees.
For safety-related systems covered by other functional safety standards, the requirements of
this standard should be considered in order to identify the appropriate measures that should
be taken with relation to EMC and functional safety.
NOTE This standard can also be used as a guide for considering EMC requirements for other systems having a
direct contribution to safety.

2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-161, International Electrotechnical Vocabulary (IEV) – Part 161: Electromagnetic
compatibility
IEC TR 61000-1-6, Electromagnetic compatibility (EMC) – Part 1-6: General – Guide to the
assessment of measurement uncertainty
IEC TR 61000-2-5, Electromagnetic compatibility (EMC) – Part 2-5: Environment –
Description and classification of electromagnetic environments
IEC 61000-4-X (all parts), Electromagnetic compatibility (EMC) – Part 4: Testing and
measurement techniques
IEC 61000-4-1, Electromagnetic compatibility (EMC) – Part 4-1: Testing and measurement
techniques – Overview of IEC 61000-4 series
IEC 61000-6-7, Electromagnetic compatibility (EMC) – Part 6-7: Generic standards –
Immunity requirements for equipment intended to perform functions in a safety-related system
(functional safety) in industrial locations
IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic
safety-related systems
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-161 as well
as the following apply.
3.1.1
degradation (of performance)
undesired departure in the operational performance of any device, equipment or system from
its intended performance
Note 1 to entry: The term "degradation" can apply to temporary or permanent failure.
[SOURCE: IEC 60050-161:1990, 161-01-19]
3.1.2
electrical/electronic/programmable electronic
E/E/PE
based on electrical and/or electronic and/or programmable electronic technology
Note 1 to entry: The term is intended to cover any and all devices or systems operating on electrical principles.
EXAMPLE Electrical/electronic/programmable electronic devices include
– electro-mechanical devices (electrical);
– solid-state non-programmable electronic devices (electronic);
– electronic devices based on computer technology (programmable electronic).

– 10 – IEC 61000-1-2:2016 © IEC 2016
[SOURCE: IEC 61508-4:2010, 3.2.13]
3.1.3
electromagnetic compatibility
EMC
ability of an equipment or system to function satisfactorily in its electromagnetic environment
without introducing intolerable electromagnetic disturbances to anything in that environment
[SOURCE: IEC 60050-161:1990, 161-01-07]
3.1.4
EMC planning
engineering method by which EMC aspects of a project are systematically considered and
investigated in order to achieve EMC
Note 1 to entry: All activities connected to EMC planning are described in an EMC plan.
3.1.5
E/E/PE system
system for control, protection or monitoring based on one or more electrical/electronic
programmable electronic (E/E/PE) devices, including all elements of the system such as
power supplies, sensors and other input devices, data highways and other communications
paths, and actuators and other output devices
[SOURCE: IEC 61508-4:2010, 3.3.2]
3.1.6
E/E/PE system safety integrity requirements specification
specification containing the safety integrity requirements of the safety functions that have to
be performed by the safety-related systems
Note 1 to entry: This specification is one part (the safety integrity part) of the E/E/PE system safety requirements
specification (see 7.10 and 7.10.2.7 of IEC 61508-1:2010).
3.1.7
E/E/PE system safety requirements specification
SSRS
specification containing, for each safety function, the safety function requirements (what the
function does), and the safety integrity requirements (the likelihood of the safety function
being performed satisfactorily) that have to be performed/met by the safety-related systems
Note 1 to entry: This note applies to the French language only.
3.1.8
(electromagnetic) compatibility level
specified electromagnetic disturbance level used as a reference level for co-ordination in the
setting of emission and immunity limits
Note 1 to entry: By convention, the compatibility level is chosen so that there is only a small probability that it will
be exceeded by the actual disturbance level. However, electromagnetic compatibility is achieved only if the
emission and immunity levels are controlled such that, at each location, the disturbance level resulting from the
cumulative emissions is lower than the immunity level for each device, equipment and system situated at the same
location.
Note 2 to entry: The compatibility level may be phenomenon, time or location dependent.
[SOURCE: IEC 60050-161:1990, 161-03-10]

3.1.9
electromagnetic disturbance
any electromagnetic phenomenon which may degrade the performance of a device,
equipment or system
Note 1 to entry: An electromagnetic disturbance may be an electromagnetic noise, an unwanted signal or a
change in the propagation medium itself.
[SOURCE: IEC 60050-161:1990, 161-01-05, modified – the words " or adversely affect living
or inert matter" have been deleted]
3.1.10
electromagnetic environment
totality of electromagnetic phenomena existing at a given location
[SOURCE: IEC 60050-161:1990, 161-01-01]
3.1.11
electromagnetic interference
EMI
degradation of the performance of an equipment, transmission channel or system caused by
an electromagnetic disturbance
Note 1 to entry: Disturbance and interference are respectively cause and effect.
Note 2 to entry: This note applies to the French language only.
[SOURCE: IEC 60050-161:1990, 161-01-06]
3.1.12
element
part of a system comprising a single component or any group of components that performs
one or more element safety functions.
Note 1 to entry: An element may comprise hardware and/or software.
Note 2 to entry: A typical element is a sensor, programmable controller or final element
[SOURCE: IEC 61508-4:2010, 3.4.5, modified – the word "subsystem" has been replaced by
"system"]
3.1.13
element safety function
that part of a safety function which is implemented by an element
[SOURCE: IEC 61508-4:2010, 3.5.3]
3.1.14
equipment
general term that refers to a wide variety of possible elements, modules, devices and
assemblies of products
3.1.15
equipment under control
EUC
equipment, machinery, apparatus or plant used for manufacturing, process, transportation,
medical or other activities
Note 1 to entry: The EUC control system is separate and distinct from the EUC.

– 12 – IEC 61000-1-2:2016 © IEC 2016
Note 2 to entry: This note applies to the French language only.
[SOURCE: IEC 61508-4:2010, 3.2.1]
3.1.16
equipment requirements specification
ERS
equipment specification covering safety-related requirements only with regard to
electromagnetic phenomena
Note 1 to entry: An equipment requirements specification (ERS) is created for each item of equipment within the
safety-related system. Included in each equipment requirements specification is an electromagnetic characteristics
specification based upon the maximum electromagnetic environment expected over the lifetime for that particular
item of equipment.
Note 2 to entry: This note applies to the French language only.
3.1.17
failure
termination of the ability of a functional unit to provide a required function or operation of a
functional unit in any way other than as required
Note 1 to entry: This is based on IEC 60050-191:1990, 191-04-01, with changes to include systematic failures
due to, for example, deficiencies in specification or software.
Note 2 to entry: See IEC61508-4 for the relationship between faults and failures, both in the IEC 61508 series
and IEC 60050-191.
Note 3 to entry: Performance of required functions necessarily excludes certain behaviour, and some functions
may be specified in terms of behaviour to be avoided. The occurrence of such behaviour is a failure.
Note 4 to entry: Failures are either random (in hardware) or systematic (in hardware or software), see IEC 61508-
4.
[SOURCE: IEC 61508-4:2010, 3.6.4, modified – in Notes 2 and 4 to entry, the figure and
subclause numbers have been replaced by IEC 61508-4.]
3.1.18
fault
abnormal condition that may cause a reduction in, or loss of, the capability of a functional unit
to perform a required function
Note 1 to entry: IEC 60050:1990, 191-05-01, defines “fault” as a state characterised by the inability to perform a
required function, excluding the inability during preventative maintenance or other planned actions, or due to lack
of external resources.
[SOURCE: ISO/IEC 2382-14:1997, 14.01.10]
3.1.19
functional safety
part of the overall safety relating to the EUC and the EUC control system that depends on the
correct functioning of the E/E/PE safety-related systems and other risk reduction measures
Note 1 to entry: In the context of this EMC document, functional safety is that part of the overall safety relating to
the electromagnetic environment in which the safety-related system exists.
[SOURCE: IEC 61508-4:2010, 3.1.12, modified – a note has been added.]
3.1.20
installation
combination of equipment, components and systems assembled and/or erected (individually)
in a given area
3.1.21
safety function
function to be implemented by an E/E/PE safety-related system or other risk reduction
measures, that is intended to achieve or maintain a safe state for the EUC, in respect of a
specific hazardous event
EXAMPLE Examples of safety functions include:
• functions that are required to be carried out as positive actions to avoid hazardous situations (for example
switching off a motor); and
• functions that prevent actions being taken (for example preventing a motor starting).
[SOURCE: IEC 61508-4:2010, 3.5.1]
3.1.22
safety integrity level
SIL
discrete level (one out of a possible four), corresponding to a range of safety integrity values,
where safety integrity level 4 has the highest level of safety integrity and safety integrity
level 1 has the lowest
Note 1 to entry: The target failure measures for the four safety integrity levels are specified in Tables 2 and 3 of
IEC 61508-1:2010.
Note 2 to entry: Safety integrity levels are used for specifying the safety integrity requirements of the safety
functions to be allocated to the E/E/PE safety-related systems.
Note 3 to entry: A safety integrity level (SIL) is not a property of a system, element or component. The correct
interpretation of the phrase “SIL n safety-related system” (where n is 1, 2, 3 or 4) is that the system is potentially
capable of supporting safety functions with a safety integrity level up to n.
Note 4 to entry: This note applies to the French language only.
[SOURCE: IEC 61508-4:2010, 3.5.8]
3.1.23
safety manual for compliant items
document that provides all the information relating to the functional safety of an element, in
respect of specified element safety functions, that is required to ensure that the system meets
the requirements of IEC 61508 series
3.1.24
safety-related system
designated system that both
– implements the required safety functions necessary to achieve or maintain a safe state for
the EUC; and
– is intended to achieve, on its own or with other E/E/PE safety-related systems and other
risk reduction measures, the necessary safety integrity for the required safety functions
Note 1 to entry: A safety-related system includes all the hardware, software and supporting services (for example,
power supplies) necessary to carry out the specified safety function (sensors, other input devices, final elements
(actuators) and other output devices are therefore included in the safety-related system).
Note 2 to entry: For further information, see IEC 61508-4.
[SOURCE: IEC 61508-4:2010, 3.4.1, modified – the original note 2 has been modified.]
3.1.25
systematic capability
measure (expressed on a scale of SC 1 to SC 4) of the confidence that the systematic safety
integrity of an element meets the requirements of the specified SIL, in respect of the specified
element safety function, when the element is applied in accordance with the instructions
specified in the compliant item safety manual for the element

– 14 – IEC 61000-1-2:2016 © IEC 2016
Note 1 to entry: Systematic capability is determined with reference to the requirements for the avoidance and
control of systematic faults (see IEC 61508-2 and IEC 61508-3).
Note 2 to entry: What is a relevant systematic failure mechanism will depend on the nature of the element. For
example, for an element comprising solely software, only software failure mechanisms will need to be considered.
For an element comprising hardware and software, it will be necessary to consider both systematic hardware and
software failure mechanisms.
Note 3 to entry: A systematic capability of SC N for an element, in respect of the specified element safety
function, means that the systematic safety integrity of SIL N has been met when the element is applied in
accordance wit
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