IEC 61496-1:2020

Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements and tests

IEC 61496-1:2020 specifies general requirements for the design, construction and testing of non-contact electro-sensitive protective equipment (ESPE) designed specifically to detect persons or part of a person as part of a safety-related system. Special attention is directed to functional and design requirements that ensure an appropriate safety-related performance is achieved. An ESPE can include optional safety-related functions, the requirements for which are given in Annex A.
This document is intended to be used with a subsequent part of IEC 61496 that provides particular requirements based on the sensing technology.
Where a part covering the sensing technology does not exist, IEC TS 62998-1 is used.
Where the IEC 61496 series does not contain all necessary provisions, IEC TS 62998-1 is used.
It is an additional possibility to combine those aspects covered by the IEC 61496 series in addition to IEC TS 62998-1.
This document does not specify the dimensions or configuration of the detection zone and its disposition in relation to hazards in any particular application, nor what constitutes a hazardous state of any machine. It is restricted to the functioning of the ESPE and how it interfaces with the machine.
While a data interface can be used to control optional safety-related ESPE functions (Annex A), this document does not provide specific requirements. Requirements for these safety-related functions can be determined by consulting other standards (for example, IEC 61508 (all parts), IEC TS 62046, IEC 62061, and ISO 13849-1).
This document can be relevant to applications other than those for the protection of persons, for example for the protection of machinery or products from mechanical damage. In those applications, different requirements can be appropriate, for example when the materials that have to be recognized by the sensing function have different properties from those of persons.
This document does not deal with requirements for ESPE functions not related to the protection of persons (e.g. using sensing unit data for navigation).
This document does not deal with electromagnetic compatibility (EMC) emission requirements.
IEC 61496-1:2020 cancels and replaces the third edition published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) It has been clarified that some requirements for ESPEs that are dependent on sensing technology are not included in IEC 61496-1. They are provided in a subsequent part of IEC 61496.
b) Requirements for protection against environmental influences from subsequent parts of IEC 61496 that are common to all ESPEs have been consolidated into IEC 61496-1.
c) Some test procedures in IEC 61496-1 were incomplete. They have been expanded with more detail and step by step procedures.
d) Some requirements and procedures in IEC 61496-1 are now covered by new generic machine safety standards. The requirements in IEC 61496-1 have been harmonized with references to the new generic standards.

Sécurité des machines - Equipements de protection électrosensibles - Partie 1: Exigences générales et essais

L'IEC 61496-1:2020 définit les exigences générales de conception, de construction et d'essai des équipements de protection électrosensibles (ESPE) sans contact spécifiquement conçus pour détecter des personnes au sein d’un système relatif à la sécurité. Une attention particulière est accordée aux exigences de fonctionnement et de conception assurant la satisfaction aux performances relatives à la sécurité appropriées. Un ESPE peut proposer des fonctions facultatives liées à la sécurité: les exigences relatives à celles-ci sont données à l’Annexe A.
L'IEC 61496-1:2020 est destiné à être utilisé avec une partie ultérieure de l’IEC 61496 qui définit des exigences particulières en fonction de la technologie de détection.
En l’absence d’une partie couvrant la technologie de détection, l’IEC TS 62998-1 est utilisée.
Dans le cas où la série IEC 61496 ne contient pas toutes les dispositions nécessaires, l’IEC TS 62998-1 est utilisée.
Il est en outre possible de combiner ces aspects couverts par la série IEC 61496 à l’IEC TS 62998-1.
Le présent document ne spécifie ni les dimensions ou la configuration de la zone de détection, ni sa disposition par rapport aux dangers dans toute application particulière, ni ce qui constitue un état dangereux pour toute machine donnée. Il se limite au fonctionnement de l’ESPE et à son interface avec la machine.
Bien qu’une interface de données puisse être utilisée pour commander des fonctions de l'ESPE relatives à la sécurité facultatives (Annexe A), le présent document ne fournit pas d’exigences particulières. Les exigences liées à ces fonctions relatives à la sécurité peuvent être déterminées en consultant d'autres normes (par exemple, l'IEC 61508 (toutes les parties), l’IEC 62046, l’IEC 62061, et l'ISO 13849-1).
Le présent document peut être pertinent pour des applications autres que la protection des personnes, par exemple la protection des machines ou des produits contre des dommages mécaniques. Dans ces applications, des exigences différentes peuvent être nécessaires, par exemple lorsque les matériaux qui doivent être reconnus par le dispositif de détection ont des caractéristiques différentes de celles des personnes.
Le présent document ne traite pas des exigences relatives aux fonctions de l’ESPE non liées à la protection des personnes (en utilisant, par exemple, les données de l’élément de détection en matière de navigation).
Le présent document ne traite pas des exigences d’émission relatives à la compatibilité électromagnétique (CEM).
L'IEC 61496-1:2020 annule et remplace la troisième édition parue en 2012. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) Il a été défini que certaines exigences relatives aux ESPE dépendant de la technologie de détection n’étaient pas incluses dans l’IEC 61496-1. Ces exigences sont fournies dans une partie ultérieure de l’IEC 61496.
b) Les exigences de protection contre les influences environnementales issues des parties ultérieures de l’IEC 61496 et qui sont communes à tous les ESPE ont été consolidées dans l’IEC 61496-1.
c) Certaines procédures d’essai de l’IEC 61496-1 étaient incomplètes. Elles ont été enrichies par des procédures plus détaillées et étape par étape.
d) Certaines exigences et procédures de l’IEC 61496-1 sont désormais couvertes par de nouvelles normes génériques relatives à la sécurité des machines. Les exigences de l’IEC 61496-1 ont été harmonisées avec des références à ces nouvelles normes génériques.

General Information

• Status: Published
• Publication Date: 13-Jul-2020
• ICS: 13.110 - Safety of machinery
• ICS: 29.260.99 - Other electrical equipment for working in special conditions
• Technical Committee: TC 44 - Safety of machinery - Electrotechnical aspects
• Drafting Committee: MT 61496-1&2 - TC 44/MT 61496-1&2
• Current Stage: PPUB - Publication issued
• Start Date: 14-Jul-2020
• Completion Date: 26-Jun-2020

Relations

• Revises: IEC 61496-1:2012/COR1:2015 - Corrigendum 1 Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements and tests
• Effective Date: 05-Sep-2023
• Revises: IEC 61496-1:2012 - Safety of machinery - Electro-sensitive protective equipment - Part 1: General requirements and tests
• Effective Date: 05-Sep-2023

Overview

IEC 61496-1:2020 is an international standard issued by the International Electrotechnical Commission (IEC) that defines the general requirements and testing protocols for Electro-Sensitive Protective Equipment (ESPE) used in machinery safety. Specifically, it addresses non-contact ESPE systems designed to detect the presence of persons or parts of persons as a critical component of safety-related control systems. The standard focuses on ensuring these safety devices achieve an appropriate performance level through rigorous functional, design, and environmental requirements and comprehensive testing.

This edition, which supersedes the 2012 version, includes significant updates such as harmonization with generic machine safety standards and expanded test procedures for improved clarity and application.

Key Topics

• Scope and Purpose: IEC 61496-1:2020 applies to the design, construction, and type testing of ESPE used for person detection in safety-related systems. It excludes defining detection zone dimensions or hazardous machine states since those depend on specific applications.

• Functional Requirements: The standard outlines functional requirements including normal operation, sensing capabilities, and performance levels (Performance Level - PL, Safety Integrity Level - SIL) required based on ESPE type (Type 1, 2, 3, 4).

• Design Requirements: It covers design aspects such as electrical supply, fault detection, electrical and non-electrical components, switching devices (OSSDs), adjustment means, and protection against common cause failures.

• Environmental Requirements: The standard mandates resistance to environmental factors like temperature variations, humidity, electrical disturbances, mechanical influences, and light interference to ensure reliable operation.

• Testing Procedures: Comprehensive type testing includes functional tests, performance under fault conditions, environmental robustness, validation of programmable or complex integrated circuits, and specific tests for optional safety features.

• Optional Safety Functions: Annex A details additional ESPE functions such as external device monitoring (EDM), stopping performance monitors, start/restart interlocks, muting, and the setting of detection zones or safety parameters.

• Marking and Documentation: Requirements for clear marking, labeling, terminal identification, and accompanying documents to ensure safe and correct usage are included.

Applications

IEC 61496-1:2020 is essential for manufacturers, designers, and users of safety equipment in industrial settings where machinery operation poses risks to personnel. Key application areas include:

• Industrial Automation: Integration of ESPE in automated machinery control systems to detect unauthorized access or ensure operator safety.

• Robotics: Use of electro-sensitive devices in collaborative robot cells to monitor human presence and prevent accidents.

• Manufacturing Lines: Employing safety light curtains and sensors to safeguard operators from moving parts.

• Protective Systems: Designing systems to prevent machine injuries by automatically stopping or controlling the machine when presence is detected.

• Machine and Product Protection: Beyond person safety, ESPEs can also protect machinery and products from damage by detecting foreign objects or materials.

Related Standards

IEC 61496-1:2020 is part of the IEC 61496 series and should be used in conjunction with:

• IEC 61496-2 and Subsequent Parts: Covering particular requirements based on different sensing technologies.

• IEC TS 62998-1: Applied where specific sensing technology parts are unavailable; complements IEC 61496 standards.

• IEC 61508: Functional safety of electrical/electronic systems; useful for safety-related functions of ESPE.

• IEC TS 62046: Techniques for determining the required performance level and validating safety functions.

• IEC 62061: Safety of machinery - functional safety of electrical control systems.

• ISO 13849-1: Safety of machinery - safety-related parts of control systems using the performance level concept.

These standards build a comprehensive framework for design, testing, and validation of safety equipment ensuring machinery protection aligns with internationally accepted safety requirements.

Summary

IEC 61496-1:2020 is a critical reference for ensuring the reliability and safety of non-contact electro-sensitive protective equipment used to safeguard personnel around machinery. By defining rigorous functional, design, environmental, and testing standards, it supports the development of effective safety systems that can adapt to different technologies and environments. Compliance with this standard contributes to reducing workplace accidents and enhancing machinery safety performance worldwide.

Standards Content (Sample)

IEC 61496-1 ®
Edition 4.0 2020-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of machinery – Electro-sensitive protective equipment –
Part 1: General requirements and tests

Sécurité des machines – Équipements de protection électrosensibles –
Partie 1: Exigences générales et essais

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite ni
utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et
les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and once 67 000 electrotechnical terminology entries in English and
a month by email. French extracted from the Terms and Definitions clause of IEC
publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or need CISPR.

further assistance, please contact the Customer Service

Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC - Le premier dictionnaire d'électrotechnologie en ligne au monde,
webstore.iec.ch/advsearchform avec plus de 22 000 articles terminologiques en anglais et en
La recherche avancée permet de trouver des publications IEC français, ainsi que les termes équivalents dans 16 langues
en utilisant différents critères (numéro de référence, texte, additionnelles. Egalement appelé Vocabulaire
comité d’études,…). Elle donne aussi des informations sur les Electrotechnique International (IEV) en ligne.

projets et les publications remplacées ou retirées.
Glossaire IEC - std.iec.ch/glossary
IEC Just Published - webstore.iec.ch/justpublished 67 000 entrées terminologiques électrotechniques, en anglais
Restez informé sur les nouvelles publications IEC. Just et en français, extraites des articles Termes et Définitions des
Published détaille les nouvelles publications parues. publications IEC parues depuis 2002. Plus certaines entrées
Disponible en ligne et une fois par mois par email. antérieures extraites des publications des CE 37, 77, 86 et
CISPR de l'IEC.
Service Clients - webstore.iec.ch/csc
Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[e-mail].
Electropedia - www.electropedia.org

IEC 61496-1 ®
Edition 4.0 2020-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of machinery – Electro-sensitive protective equipment –

Part 1: General requirements and tests

Sécurité des machines – Équipements de protection électrosensibles –

Partie 1: Exigences générales et essais

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 13.110; 29.260.99 ISBN 978-2-8322-8435-3

– 2 – IEC 61496-1:2020 © IEC 2020
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 9
3 Terms and definitions . 10
4 Functional, design and environmental requirements . 14
4.1 Functional requirements . 14
4.1.1 Normal operation . 14
4.1.2 Sensing function . 15
4.1.3 Types of ESPE . 15
4.1.4 Types and required safety performance . 15
4.1.5 Required PL or SIL and corresponding ESPE type . 16
r
4.2 Design requirements . 16
4.2.1 Electrical supply . 16
4.2.2 Fault detection requirements . 17
4.2.3 Electrical equipment of the ESPE. 18
4.2.4 Output signal switching devices (OSSDs) . 19
4.2.5 Indicator lights and displays . 21
4.2.6 Adjustment means . 22
4.2.7 Disconnection of electrical assemblies . 22
4.2.8 Non-electrical components . 22
4.2.9 Common cause failures . 22
4.2.10 Programmable or complex integrated circuits . 22
4.2.11 Software, programming, functional design of integrated circuits . 22
4.2.12 Integrity of the ESPE detection capability. 23
4.2.13 Test piece . 23
4.3 Environmental requirements . 23
4.3.1 Ambient air temperature range and humidity . 23
4.3.2 Electrical disturbances . 23
4.3.3 Mechanical environment . 26
4.3.4 Enclosures . 27
4.3.5 Light interference . 27
5 Testing . 28
5.1 General . 28
5.1.1 Type tests . 28
5.1.2 Test conditions . 29
5.1.3 Test results . 30
5.2 Functional tests . 30
5.2.1 Sensing function . 30
5.2.2 Response time . 30
5.2.3 Limited functional tests . 31
5.2.4 Periodic test. 31
5.2.5 Indicator lights and displays . 32
5.2.6 Means of adjustment . 32
5.2.7 Rating of components . 32
5.2.8 Output signal switching devices (OSSD) . 32

5.3 Performance testing under fault conditions . 33
5.3.1 General. 33
5.3.2 Type 1 ESPE . 33
5.3.3 Type 2 ESPE . 33
5.3.4 Type 3 ESPE . 33
5.3.5 Type 4 ESPE . 33
5.4 Environmental tests . 34
5.4.1 Rated supply voltage . 34
5.4.2 Ambient temperature variation and humidity . 34
5.4.3 Effects of electrical disturbances . 35
5.4.4 Mechanical influences . 40
5.4.5 Enclosures . 42
5.4.6 Light interference . 42
5.5 Validation of programmable or complex integrated circuits . 44
5.5.1 General. 44
5.5.2 Complex or programmable integrated circuits . 44
5.5.3 Software, programming, functional design of integrated circuits . 44
5.5.4 Test results analysis statement . 44
6 Marking for identification and for safe use . 44
6.1 General . 44
6.2 ESPE supplied from a dedicated power supply . 45
6.3 ESPE supplied from an internal electrical power source . 45
6.4 Adjustment . 45
6.5 Enclosures . 45
6.6 Control devices . 46
6.7 Terminal markings . 46
6.8 Marking durability . 46
7 Accompanying documents . 46
Annex A (normative) Optional functions of the ESPE . 49
A.1 General . 49
A.2 External device monitoring (EDM) . 49
A.2.1 Functional requirements . 49
A.2.2 Fault condition requirements . 49
A.2.3 Verification . 49
A.2.4 Information for use . 50
A.3 Stopping performance monitor (SPM) . 50
A.3.1 Functional requirements . 50
A.3.2 Fault condition requirements . 50
A.3.3 Verification . 50
A.3.4 Marking. 51
A.4 Secondary switching device (SSD) . 51
A.4.1 Functional requirements . 51
A.4.2 Fault condition requirements . 51
A.4.3 Verification . 51
A.5 Start interlock . 51
A.5.1 Functional requirements . 51
A.5.2 Fault condition requirements . 52
A.5.3 Verification . 52
A.5.4 Indication . 52

– 4 – IEC 61496-1:2020 © IEC 2020
A.6 Restart interlock . 52
A.6.1 Functional requirements . 52
A.6.2 Fault condition requirements . 52
A.6.3 Verification . 52
A.6.4 Indication . 53
A.7 Muting. 53
A.7.1 General. 53
A.7.2 Functional requirements . 53
A.7.3 Fault condition requirements . 53
A.7.4 Verification . 53
A.7.5 Indication . 54
A.8 Reinitiation of machine operation facility . 54
A.8.1 General. 54
A.8.2 Functional requirements . 54
A.8.3 Fault condition requirements . 54
A.8.4 Verification . 54
A.9 Setting the detection zone and/or other safety-related parameters . 55
A.9.1 Functional requirements . 55
A.9.2 Verification . 55
Annex B (normative) Catalogue of single faults affecting the electrical equipment of
the ESPE, to be applied as specified in 5.3 . 56
B.1 General . 56
B.2 Conductors and connectors . 56
B.3 Switches . 56
B.4 Discrete electrical components . 56
B.5 Solid-state electrical components . 56
B.6 Motors . 56
Annex C (informative) Design review . 57
Bibliography . 58

Figure 1 – Examples of ESPEs using safety-related communication interfaces . 21
Figure 2 – Test setup for the EMC test of ESPEs with safety-related communication
interfaces . 30

Table 1 – Types and required safety performance . 15
Table 2 – Required PL or SIL and corresponding ESPE type . 16
r
Table 3 – Supply voltage dips and interruptions for AC power ports . 24
Table 4 – Supply voltage dips and interruptions for DC power ports . 24
Table 5 – Vibration test for stationary use . 40
Table 6 – Sinusoidal vibration test for ground vehicle installations . 40
Table 7 – Broadband vibration test for ground vehicle installations . 41
Table 8 – Shock test for stationary use . 41
Table 9 – Shock test for ground vehicle installation. 42

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF MACHINERY –
ELECTRO-SENSITIVE PROTECTIVE EQUIPMENT –

Part 1: General requirements and tests

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) 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 61496-1 has been prepared by IEC technical committee 44: Safety
of machinery – Electrotechnical aspects.
This fourth edition cancels and replaces the third edition published in 2012. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) It has been clarified that some requirements for ESPEs that are dependent on sensing
technology are not included in IEC 61496-1. They are provided in a subsequent part of
IEC 61496.
b) Requirements for protection against environmental influences from subsequent parts of
IEC 61496 that are common to all ESPEs have been consolidated into IEC 61496-1.

– 6 – IEC 61496-1:2020 © IEC 2020
c) Some test procedures in IEC 61496-1 were incomplete. They have been expanded with
more detail and step by step procedures.
d) Some requirements and procedures in IEC 61496-1 are now covered by new generic
machine safety standards. The requirements in IEC 61496-1 have been harmonized with
references to the new generic standards.
The text of this International Standard is based on the following documents:
FDIS Report on voting
44/874/FDIS 44/877/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all the parts in the IEC 61496 series, published under the general title Safety of
machinery – Electro-sensitive protective equipment, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
An electro-sensitive protective equipment (ESPE) is applied to machinery presenting a risk of
personal injury. It provides protection by causing the machine to revert to a safe condition
before a person can be placed in a hazardous situation.
This document provides general design and performance requirements of ESPEs for use over
a broad range of applications. Essential features of equipment meeting the requirements of
this document are the appropriate level of safety-related performance provided and the
built-in periodic functional checks/self-checks that are specified to ensure that this level of
performance is maintained.
Each type of machine presents its own particular hazards and it is not the purpose of this
document to recommend the manner of application of the ESPE to any particular machine.
The application of the ESPE is a matter for agreement between the equipment supplier, the
machine user and the enforcing authority, and in this context attention is drawn to the relevant
guidance established internationally, for example ISO 12100.
This document specifies technical requirements of electro-sensitive protective equipment. The
application of this document may require the use of substances and/or test procedures that
could be injurious to health unless adequate precautions are taken. Conformance with this
document in no way absolves either the supplier or the user from statutory obligations relating
to the safety and health of persons during the use of the equipment covered by this document.
The requirements of this document are highly dependent on analysis and expertise in specific
test and measurement techniques. In order to provide a high level of confidence, independent
review is recommended.
– 8 – IEC 61496-1:2020 © IEC 2020
SAFETY OF MACHINERY –
ELECTRO-SENSITIVE PROTECTIVE EQUIPMENT –

Part 1: General requirements and tests

1 Scope
This part of IEC 61496 specifies general requirements for the design, construction and testing
of non-contact electro-sensitive protective equipment (ESPE) designed specifically to detect
persons or part of a person as part of a safety-related system. Special attention is directed to
functional and design requirements that ensure an appropriate safety-related performance is
achieved. An ESPE can include optional safety-related functions, the requirements for which
are given in Annex A.
NOTE "Non-contact" means that physical contact is not required for sensing.
This document is intended to be used with a subsequent part of IEC 61496 that provides
particular requirements based on the sensing technology.
EXAMPLE This document and IEC 61496-2 are used for AOPDs; this document and IEC 61496-3 are used for
AOPDDRs.
Where a part covering the sensing technology does not exist, IEC TS 62998-1 is used.
Where the IEC 61496 series does not contain all necessary provisions, IEC TS 62998-1 is
used.
It is an additional possibility to combine those aspects covered by the IEC 61496 series in
addition to IEC TS 62998-1.
This document does not specify the dimensions or configuration of the detection zone and its
disposition in relation to hazards in any particular application, nor what constitutes a
hazardous state of any machine. It is restricted to the functioning of the ESPE and how it
interfaces with the machine.
While a data interface can be used to control optional safety-related ESPE functions
(Annex A), this document does not provide specific requirements. Requirements for these
safety-related functions can be determined by consulting other standards (for example,
IEC 61508 (all parts), IEC 62046, IEC 62061, and ISO 13849-1).
This document can be relevant to applications other than those for the protection of persons,
for example for the protection of machinery or products from mechanical damage. In those
applications, different requirements can be appropriate, for example when the materials that
have to be recognized by the sensing function have different properties from those of
persons.
This document does not deal with requirements for ESPE functions not related to the
protection of persons (e.g. using sensing unit data for navigation).
This document does not deal with electromagnetic compatibility (EMC) emission
requirements.
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 60068-2-6, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-27, Environmental testing – Part 2-27: Tests – Test Ea and guidance: Shock
IEC 60204-1:2016, Safety of machinery – Electrical equipment of machines – Part 1: General
requirements
IEC 60417, Graphical symbols for use on equipment (Available from: http://www.graphical-
symbols.info/equipment)
IEC 60445, Basic and safety principles for man-machine interface, marking and
identification – Identification of equipment terminals, conductor terminations and conductors
IEC 60529, Degrees of protection provided by enclosures (IP code)
IEC 60721-3-5, Classification of environmental conditions – Part 3: Classification of groups of
environmental parameters and their severities – Section 5: Ground vehicle installations
IEC TR 60721-4-3, Classification of environmental conditions – Part 4-3: Guidance for the
correlation and transformation of environmental condition classes of IEC 60721-3 to the
environmental tests of IEC 60068 – Stationary use at weatherprotected locations
IEC 60947-1:2007, Low-voltage switchgear and controlgear – Part 1: General rules
IEC 60947-1:2007/AMD2:2014
IEC 61000-4-2:2008, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
IEC 61000-4-3:2006/AMD1:2007
IEC 61000‑4‑3:2006/AMD2:2010
IEC 61000-4-4:2012, Electromagnetic compatibility (EMC) – Part 4-4: Testing and
measurement techniques – Electrical fast transient/burst immunity test
IEC 61000-4-5:2014, Electromagnetic compatibility (EMC) – Part 4-5: Testing and
measurement techniques – Surge immunity test
IEC 61000-4-5:2014/AMD1:2017
IEC 61000-4-6:2013, Electromagnetic compatibility (EMC) – Part 4-6: Testing and
measurement techniques – Immunity to conducted disturbances, induced by radio-frequency
fields
IEC 61000-4-11:2020, Electromagnetic compatibility (EMC) – Part 4-11: Testing and
measurement techniques – Voltage dips, short interruptions and voltage variations immunity
tests for equipment with input current up to 16 A per phase

– 10 – IEC 61496-1:2020 © IEC 2020
IEC 61000-4-29:2000, Electromagnetic compatibility (EMC) – Part 4-29: Testing and
measurement techniques – Voltage dips, short interruptions and voltage variations on d.c.
input power port immunity tests
IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic
safety-related systems
IEC 62061, Safety of machinery – Functional safety of safety-related electrical, electronic and
programmable electronic control systems
ISO 12100, Safety of machinery – General principles for design – Risk assessment and risk
reduction
ISO 13849-1, Safety of machinery – Safety-related parts of control systems – Part 1: General
principles for design
ISO 13849-2:2012, Safety of machinery – Safety-related parts of control systems – Part 2:
Validation
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
blanking
optional function that permits an object of a size greater than the detection capability of the
ESPE to be located within the detection zone without causing an OFF-state of the OSSD(s)
Note 1 to entry: Fixed blanking is a technique wherein the locations of the blanked areas of the detection zone do
not change during operation. The detection capability of the other parts of the detection zone remains unchanged.
Note 2 to entry: Floating blanking is a technique wherein the blanked area of the detection zone follows the
location of a moving object(s) during operation. The detection capability of the other areas remains unchanged.
3.2
controlling/monitoring device
part of the electro-sensitive protective equipment (ESPE) that:
– receives and processes information from the sensing device and provides signals to the
output signal switching devices (OSSD),
– monitors the sensing device and the OSSD
3.3
detection capability
sensing function parameter limit specified by the supplier that will cause actuation of the
electro-sensitive protective equipment (ESPE)
3.4
detection zone
zone within which a specified test piece will be detected by the electro-sensitive protective
equipment (ESPE)
3.5
electro-sensitive protective equipment
ESPE
assembly of devices and/or components working together for protective tripping or presence-
sensing purposes and comprising as a minimum
– a sensing device;
– controlling/monitoring devices;
– output signal switching devices and/or a safety-related data interface
Note 1 to entry: The safety-related control system associated with the ESPE, or the ESPE itself, may further
include a secondary switching device, muting functions, stopping performance monitor, etc. (see Annex A).
Note 2 to entry: A safety-related communication interface can be integrated in the same enclosure as the ESPE.
3.6
external device monitoring
EDM
means by which the electro-sensitive protective equipment (ESPE) monitors the state of
control devices which are external to the ESPE
3.7
failure
termination of the ability of an item to perform a required function
Note 1 to entry: After failure the item has a fault.
Note 2 to entry: 'Failure' is an event, as distinguished from 'fault', which is a state.
Note 3 to entry: This concept, as defined, does not apply to items consisting of software only.
Note 4 to entry: In practice, the terms fault and failure are often used synonymously.
[SOURCE: IEC 60050-191:1990, 191-04-01]
3.8
failure to danger
failure which prevents or delays all output signal switching devices going to, and/or remaining
in the OFF-state in response to a condition which, in normal operation, would result in their so
doing
3.9
fault
state of an item characterized by inability to perform a required function, excluding the
inability during preventive maintenance or other planned actions, or due to lack of external
resources
Note 1 to entry: A fault is often the result of a failure of the item itself, but may exist without prior failure.
Note 2 to entry: In English the term "fault" and its definition are identical with those given in IEC 60050-191:1990,
191-05-01. In the field of machinery, the French term "défaut" and the German term "Fehler" are used rather than
the terms "panne" and "Fehlzustand" that appear with this definition.
[SOURCE: IEC 60050-191:1990, 191-05-01]
3.10
final switching device
FSD
component of the machine's safety-related control system that interrupts the circuit to the
machine primary control element (MPCE) when the output signal switching device (OSSD)
goes to the OFF-state
– 12 – IEC 61496-1:2020 © IEC 2020
3.11
integrated circuit – complex or programmable
monolithic, hybrid or module circuit which satisfies one or more of the criteria below:
a) more than 1 000 gates are used in the digital mode;
b) more than 24 functionally different external electrical connections are available for use;
c) the functions can be programmed
Note 1 to entry: Examples include ASICs, ROMs, PROMs, EPROMs, PALs, CPUs, PLAs, and PLDs.
Note 2 to entry: The circuits may function in the analogue mode, the digital mode, or a combination of the two
modes.
3.12
integrated circuit – simple
monolithic, hybrid or module circuit which satisfies none of the criteria in 3.11
Note 1 to entry: Examples are SSI or MSI logic ICs, comparators.
Note 2 to entry: The circuits may function in the analogue mode, in the digital mode, or in a combination of the
two modes.
3.13
lock-out condition
condition, initiated by a fault, preventing normal operation of the electro-sensitive protective
equipment (ESPE)
Note 1 to entry: All output signal switching devices (OSSDs) and, where applicable, all secondary switching
devices (SSDs) are signalled to go to the OFF-state.
3.14
machine primary control element
MPCE
electrically powered element that directly controls the normal operation of a machine in such a
way that it is the last element (in time) to function when machine operation is to be initiated or
arrested
Note 1 to entry: This element can be, for example, a mains contactor, a magnetic clutch or an electrically
operated hydraulic valve.
3.15
machine secondary control element
MSCE
machine control element, independent of the machine primary control element(s), that is
capable of removing the source of power from the prime mover of the relevant hazardous
parts
Note 1 to entry: When fitted, the MSCE is normally controlled by the secondary switching device (SSD).
Note 2 to entry: This element can be, for example, a mains contactor, a magnetic clutch or an electrically
operated hydraulic valve.
3.16
muting
temporary automatic suspension of a safety function(s) by safety-related parts of the control
system
Note 1 to entry: For ESPE-muting see Clause A.7.
3.17
OFF-state
state of the output(s) of the ESPE in which the machine under control is caused to stop
running and is prevented from starting

Note 1 to entry: For example, the output circuit is interrupted and disables the flow of current.
3.18
ON-state
state of the output(s) of the ESPE in which the machine under control is allowed to run
Note 1 to entry: For example, the output circuit is complete and enables the flow of current.
3.19
output signal switching device
OSSD
component of the electro-sensitive protective equipment (ESPE) connected to the machine
control system which, when the sensing device is actuated during normal operation, responds
by going to the OFF-state
3.20
overall system stopping performance
time interval resulting from the sum of the electro-sensitive protective equipment (ESPE)
response time and the time to the cessation of hazardous machine operation
3.21
response time
maximum time between the occurrence of the event leading to the actuation of the sensing
device and the output signal switching devices (OSSD) achieving the OFF-state
Note 1 to entry: When an ESPE includes a safety-related data interface, the response time is defined at the
output of the safety-related data interface.
Note 2 to entry: When a safety-related communication interface is included in the ESPE enclosure, the response
time is defined at the output of the safety-related communication interface. In this case, the response time is also
dependent on the protocol and architecture of the communication network.
Note 3 to entry: If an ESPE has both a safety-related data interface and OSSDs, the ESPE can have a different
response time for the safety-related data interface and for the OSSDs.
3.22
restart interlock
means of preventing automatic restarting of a machine after actuation of the sensing device
during a hazardous part of the machine operating cycle, after a change in mode of operation
of the machine, and after a change in the means of start control of the machine
Note 1 to entry: Modes of operation include inch, single stroke, automatic. Means of start control include foot
switch, two-hand control, and single or double actuation of the electro-sensitive protection equipment (ESPE)
sensing device.
3.23
safety-related part of a control system
part or subpart(s) of a control system which respond(s) to input signals and generate(s)
safety-related output signals
Note 1 to entry: This also includes monitoring systems.
Note 2 to entry: The combined safety-related parts of a control system start at the points where
...