IEC 61496-2:2020

IEC 61496-2 ®
Edition 4.0 2020-07
INTERNATIONAL
STANDARD
colour
inside
Safety of machinery – Electro-sensitive protective equipment –
Part 2: Particular requirements for equipment using active opto-electronic
protective devices (AOPDs)
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IEC 61496-2 ®
Edition 4.0 2020-07
INTERNATIONAL
STANDARD
colour
inside
Safety of machinery – Electro-sensitive protective equipment –

Part 2: Particular requirements for equipment using active opto-electronic

protective devices (AOPDs)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.110; 29.260.99 ISBN 978-2-8322-8452-0

– 2 – IEC 61496-2:2020 © IEC 2020
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Functional, design and environmental requirements . 9
5 Testing . 14
6 Marking for identification and safe use . 40
7 Accompanying documents . 41
Annex A (normative) Optional functions of the ESPE . 42
Annex AA (informative) Type 2 AOPD periodic test configurations . 46

Figure 1 – Limit area for the protection against the risk of beam bypass . 12
Figure 2 – Limit of vertical and horizontal misalignment . 13
Figure 3 – Test piece at 45° . 18
Figure 4 – Test piece at 90° . 18
Figure 5 – Verifying sensing function by moving the test piece (TP) through the
detection zone near the emitter, near the receiver/retro-reflector target and at the
midpoint . 19
Figure 6 – Limit values for the effective aperture angle (EAA) . 21
Figure 7 – Determination of the minimum detection capability . 22
Figure 8 – Measuring method for EAA (direction) . 23
Figure 9 – Prism test to measure EAA of each beam . 25
Figure 10 – EAA test using prism . 26
Figure 11 – Example of optical subsystem . 27
Figure 12 – Example of SMD LED Model . 28
Figure 13 – Example of intensity distribution of emitting element . 28
Figure 14 – Example of emitter model with beams internally blocked by aperture stop . 29
Figure 15 – Example of receiving unit with off axis beam portion reflected internally on
mechanical elements . 29
Figure 16 – Example of test piece inside model of optical subsystem with passing
radiation on the receiver . 30
Figure 17 – Example of emitting unit adjusted at the limit . 31
Figure 18 – Extraneous reflection test with mirror outside of limit area . 32
Figure 19 – AOPD misalignment test . 34
Figure 20 – Light interference test – Direct method . 36
Figure 21 – Light interference test – Test set-up with incandescent light source . 37
Figure 22 – Light interference test – Test set-up with fluorescent light source . 38
Figure 23 – Light interference test – Test set-up with flashing beaconlight source . 39
Figure AA.1 – Single beam sensing device . 46
Figure AA.2 – Series connection of single beam sensing devices . 46
Figure AA.3 – Assembly of multiple beams tested individually. 46
Figure AA.4 – Example of type 2 AOPD with internal test . 47

Table 1 – Correspondences of requirements/testing and AOPD designs . 15
Table 2 – Maximum permissible angle of misalignment (in degrees) for a type 2 ESPE
depending on the dimensions of the light curtain . 32
Table 3 – Maximum permissible angle of misalignment (in degrees) for a type 3 ESPE
depending on the dimensions of the light curtain . 33
Table 4 – Maximum permissible angle of misalignment (in degrees) for a type 4 ESPE
depending on the dimensions of the light curtain . 33

– 4 – IEC 61496-2:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF MACHINERY –
ELECTRO-SENSITIVE PROTECTIVE EQUIPMENT –

Part 2: Particular requirements for equipment using
active opto-electronic protective devices (AOPDs)

FOREWORD
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International Standard IEC 61496-2 has been prepared by IEC technical committee 44: Safety
of machinery – Electrotechnical aspects, in collaboration with CENELEC technical committee
44X: Safety of machinery – Electrotechnical aspects.
This fourth edition cancels and replaces the third edition published in 2013. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Requirements and test procedures in Part 2 that were found to be common to all ESPEs
have been moved to Part 1. Test procedures that are dependent on the sensing
technology remain in Part 2.
The text of this International Standard is based on the following documents:
FDIS Report on voting
44/875/FDIS 44/878/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.
This standard has the status of a product family standard and can be used as a normative
reference in a dedicated product standard for the safety of machinery.
This standard is to be used in conjunction with IEC 61496-1:2020.
This part supplements or modifies the corresponding clauses in IEC 61496-1:2020.
Where a particular clause or subclause of IEC 61496-1:2020 is not mentioned in this Part 2,
that clause or subclause applies as far as is reasonable. Where this part states "Addition",
"Modification" or "Replacement", the relevant text of IEC 61496-1:2020 is adapted
accordingly.
Clauses and subclauses which are additional to those of Part 1 are numbered sequentially,
following on the last available number in Part 1. Terminological entries (in Clause 3) which are
additional to those in Part 1 are numbered starting from 3.201. Additional annexes are
lettered from AA onwards.
A list of all parts in the IEC 61496 series, published under the general title Safety of
machinery – Electro-sensitive protective equipme
...