IEC TS 61496-4-3:2015

Safety of machinery - Electro-sensitive protective equipment - Part 4-3: Particular requirements for equipment using vision based protective devices (VBPD) - Additional requirements when using stereo vision techniques (VBPDST)

IEC TS 61496-4-3:2015(E) specifies requirements for the design, construction and testing of electro-sensitive protective equipment (ESPE) designed specifically to detect persons or parts of persons as part of a safety-related system, employing vision-based protective devices (VBPDs) using stereo vision techniques (VBPDST) for the sensing function. Special attention is directed to features which ensure that an appropriate safety-related performance is achieved.
This publication is to be read in conjunction with IEC 61496-1:2012.

General Information

• Status: Published
• Publication Date: 18-May-2015
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• 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 61496-4 - TC 44/MT 61496-4
• Current Stage: DELPUB - Deleted Publication
• Start Date: 30-Nov-2018
• Completion Date: 28-Sep-2022

Relations

• Revised: IEC TS 61496-4-3:2022 - Safety of machinery - Electro-sensitive protective equipment - Part 4-3: Particular requirements for equipment using vision based protective devices (VBPD) - Additional requirements when using stereo vision techniques (VBPDST)
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC TS 61496-4-3 ®
Edition 1.0 2015-05
TECHNICAL
SPECIFICATION
colour
inside
Safety of machinery – Electro-sensitive protective equipment –
Part 4-3: Particular requirements for equipment using vision based protective
devices (VBPD) – Additional requirements when using stereo vision techniques
(VBPDST)
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.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
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 corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 15
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 60 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and Definitions
committee,…). It also gives information on projects, replaced clause of IEC publications issued since 2002. Some entries
and withdrawn publications. have been collected from earlier publications of IEC TC 37,

77, 86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished

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details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC TS 61496-4-3 ®
Edition 1.0 2015-05
TECHNICAL
SPECIFICATION
colour
inside
Safety of machinery – Electro-sensitive protective equipment –

Part 4-3: Particular requirements for equipment using vision based protective

devices (VBPD) – Additional requirements when using stereo vision techniques

(VBPDST)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.110; 29.260.99 ISBN 978-2-8322-2611-7

– 2 – IEC TS 61496-4-3:2015 © IEC 2015
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 9
3 Terms and definitions . 9
Abbreviated terms . 12
4 Functional, design and environmental requirements . 12
4.1 Functional requirements . 12
4.1.2 Sensing function . 12
4.1.3 Types of ESPE . 15
4.1.6 Zone with limited detection capability . 15
4.2 Design requirements . 16
4.2.2 Fault detection requirements . 16
4.2.12 Integrity of the VBPDST detection capability . 17
4.2.13 Test pieces for type testing . 19
4.2.14 Wavelength . 21
4.2.15 Radiation intensity . 21
4.2.16 Mechanical construction . 21
4.3 Environmental requirements . 21
4.3.1 Ambient air temperature range and humidity . 21
4.3.5 Ambient light intensity. 21
4.3.6 Light interference . 21
4.3.7 Pollution interference . 22
4.3.8 Manual interference . 22
4.3.9 Optical occlusion (eclipsed by small object) . 23
4.3.10 Drift or ageing of components . 23
5 Testing . 23
5.1 General . 23
5.1.2 Test conditions . 23
5.1.4 Test conditions and test plan . 24
5.2 Functional tests . 24
5.2.1 Sensing function . 24
5.2.9 Verification of optical performance . 28
5.2.10 Wavelength . 28
5.2.11 Radiation intensity . 28
5.3 Performance testing under fault conditions . 28
5.3.2 Type 1 ESPE . 28
5.3.3 Type 2 ESPE . 28
5.3.4 Type 3 ESPE . 29
5.3.5 Type 4 ESPE . 29
5.4 Environmental tests . 29
5.4.2 Ambient temperature variation and humidity . 29
5.4.4 Mechanical influences . 29
5.4.6 Light interference . 30
5.4.7 Pollution interference . 36
5.4.8 Manual interference . 37

5.4.9 Optical occlusion . 37
6 Marking for identification and for safe use . 38
6.1 General . 38
7 Accompanying documents . 38
Annex A (normative) Optional functions of the ESPE . 40
A.9 Setting the detection zone and/or other safety-related parameters . 40
A.9.1 Functional requirements . 40
A.9.2 Verification . 40
A.10 Selection of multiple detection zones . 41
A.10.1 Functional requirements . 41
A.10.2 Verification . 41
Annex B (normative) Catalogue of single faults affecting the electrical equipment of
the ESPE, to be applied as specified in 5.3 . 42
B.7 Imaging sensor . 42
Annex AA (informative) The positioning of VBPDST employing a volume as a
detection zone in respect of parts of the human body . 43
AA.1 Calculation of distances for electro-sensitive protective equipment employing
vision based protective devices (VBPDST) . 43
AA.1.1 General . 43
AA.1.2 Calculation of the overall minimum distance S . 43
o
AA.1.3 Vision based protective devices with a detection capability > 40 mm and
≤ 55 mm . 44
AA.1.4 Vision based protective devices with a detection capability > 55 mm and
≤ 200 mm . 45
AA.1.5 Examples of detection zone and tolerance zone . 45
AA.2 Application examples for body detection of a VBPDST employing a volume
as a detection zone . 49
Annex BB (informative) Relationship between position accuracy and tolerance zones
for VBPDST . 51
BB.1 Probability of detection . 51
BB.2 Tolerance zone related to probability . 52
BB.3 Determination of tolerance zone for systems not providing object distance
information . 52
BB.4 Determination of tolerance zone for systems providing distance information . 53
BB.5 Tolerance zone related to systematic interferences . 54
BB.6 Adding the tolerance zone on the outer border of the detection zone . 54
Annex CC (informative) Basic principles of physics for contrast of convex
homogeneous bodies . 56
CC.1 Illumination on a surface element . 56
CC.2 Brightness of a surface element . 58
Bibliography . 63

Figure 1 – Image planes in imaging device of a VBPDST . 10
Figure 2 – 3D view of a vision based protective device using stereo vision techniques
(VBPDST) . 13
Figure 3 – 2D view of a vision based protective device using stereo vision techniques
(VBPDST) . 14
Figure 4 – Examples for periodic surface structures on the background . 28
Figure 5 – Test setup for indirect light interference on the background. 34

– 4 – IEC TS 61496-4
...

IEC TS 61496-4-3 ®
Edition 1.0 2015-05
TECHNICAL
SPECIFICATION
colour
inside
Safety of machinery – Electro-sensitive protective equipment –
Part 4-3: Particular requirements for equipment using vision based protective
devices (VBPD) – Additional requirements when using stereo vision techniques
(VBPDST)
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.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]

CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
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 corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 15
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 60 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and Definitions
committee,…). It also gives information on projects, replaced clause of IEC publications issued since 2002. Some entries
and withdrawn publications. have been collected from earlier publications of IEC TC 37,

77, 86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished

Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC TS 61496-4-3 ®
Edition 1.0 2015-05
TECHNICAL
SPECIFICATION
colour
inside
Safety of machinery – Electro-sensitive protective equipment –

Part 4-3: Particular requirements for equipment using vision based protective

devices (VBPD) – Additional requirements when using stereo vision techniques

(VBPDST)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.110; 29.260.99 ISBN 978-2-8322-2611-7

– 2 – IEC TS 61496-4-3:2015 © IEC 2015

CONTENTS
FOREWORD . 5

INTRODUCTION . 7

1 Scope . 8

2 Normative references . 9

3 Terms and definitions . 9

Abbreviated terms . 12

4 Functional, design and environmental requirements . 12
4.1 Functional requirements . 12
4.1.2 Sensing function . 12
4.1.3 Types of ESPE . 15
4.1.6 Zone with limited detection capability . 15
4.2 Design requirements . 16
4.2.2 Fault detection requirements . 16
4.2.12 Integrity of the VBPDST detection capability . 17
4.2.13 Test pieces for type testing . 19
4.2.14 Wavelength . 21
4.2.15 Radiation intensity . 21
4.2.16 Mechanical construction . 21
4.3 Environmental requirements . 21
4.3.1 Ambient air temperature range and humidity . 21
4.3.5 Ambient light intensity. 21
4.3.6 Light interference . 21
4.3.7 Pollution interference . 22
4.3.8 Manual interference . 22
4.3.9 Optical occlusion (eclipsed by small object) . 23
4.3.10 Drift or ageing of components . 23
5 Testing . 23
5.1 General . 23
5.1.2 Test conditions . 23
5.1.4 Test conditions and test plan . 24
5.2 Functional tests . 24
5.2.1 Sensing function . 24

5.2.9 Verification of optical performance . 28
5.2.10 Wavelength . 28
5.2.11 Radiation intensity . 28
5.3 Performance testing under fault conditions . 28
5.3.2 Type 1 ESPE . 28
5.3.3 Type 2 ESPE . 28
5.3.4 Type 3 ESPE . 29
5.3.5 Type 4 ESPE . 29
5.4 Environmental tests . 29
5.4.2 Ambient temperature variation and humidity . 29
5.4.4 Mechanical influences . 29
5.4.6 Light interference . 30
5.4.7 Pollution interference . 36
5.4.8 Manual interference . 37

5.4.9 Optical occlusion . 37

6 Marking for identification and for safe use . 38

6.1 General . 38

7 Accompanying documents . 38

Annex A (normative) Optional functions of the ESPE . 40

A.9 Setting the detection zone and/or other safety-related parameters . 40

A.9.1 Functional requirements . 40

A.9.2 Verification . 40

A.10 Selection of multiple detection zones . 41

A.10.1 Functional requirements . 41
A.10.2 Verification . 41
Annex B (normative) Catalogue of single faults affecting the electrical equipment of
the ESPE, to be applied as specified in 5.3 . 42
B.7 Imaging sensor . 42
Annex AA (informative) The positioning of VBPDST employing a volume as a
detection zone in respect of parts of the human body . 43
AA.1 Calculation of distances for electro-sensitive protective equipment employing
vision based protective devices (VBPDST) . 43
AA.1.1 General . 43
AA.1.2 Calculation of the overall minimum distance S . 43
o
AA.1.3 Vision based protective devices with a detection capability > 40 mm and
≤ 55 mm . 44
AA.1.4 Vision based protective devices with a detection capability > 55 mm and
≤ 200 mm . 45
AA.1.5 Examples of detection zone and tolerance zone . 45
AA.2 Application examples for body detection of a VBPDST employing a volume
as a detection zone . 49
Annex BB (informative) Relationship between position accuracy and tolerance zones
for VBPDST . 51
BB.1 Probability of detection . 51
BB.2 Tolerance zone related to probability . 52
BB.3 Determination of tolerance zone for systems not providing object distance
information . 52
BB.4 Determination of tolerance zone for systems providing distance information . 53
BB.5 Tolerance zone related to systematic interferences . 54
BB.6 Adding the tolerance zone on the outer border of the detection zone . 54

Annex CC (informative) Basic principles of physics for contrast of convex
homogeneous bodies . 56
CC.1 Illumination on a surface element . 56
CC.2 Brightness of a surface element . 58
Bibliography . 63

Figure 1 – Image planes in imaging device of a VBPDST . 10
Figure 2 – 3D view of a vision based protective device using stereo vision techniques
(VBPDST) . 13
Figure 3 – 2D view of a vision based protective device using stereo vision techniques
(VBPDST) . 14
Figure 4 – Examples for periodic surface structures on the background . 28
Figure 5 – Test setup for indirect light interference on the b
...