IEC 61496-2:2013

IEC 61496-2 ®
Edition 3.0 2013-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery – Electro-sensitive protective equipment –
Part 2: Particular requirements for equipment using active opto-electronic
protective devices (AOPDs)
Sécurité des machines – Équipements de protection électro-sensibles –
Partie 2: Exigences particulières à un équipement utilisant des appareils
protecteurs optoélectroniques actifs (AOPD)

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IEC 61496-2 ®
Edition 3.0 2013-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery – Electro-sensitive protective equipment –

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

protective devices (AOPDs)
Sécurité des machines – Équipements de protection électro-sensibles –

Partie 2: Exigences particulières à un équipement utilisant des appareils

protecteurs optoélectroniques actifs (AOPD)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 13.110; 29.260.99 ISBN 978-2-83220-587-7

– 2 – 61496-2 © IEC:2013
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Functional, design and environmental requirements . 9
4.1 Functional requirements . 9
4.2 Design requirements . 11
4.3 Environmental requirements . 14
5 Testing . 14
5.1 General . 14
5.2 Functional tests . 17
5.4 Environmental tests . 34
6 Marking for identification and safe use. 42
6.1 General . 42
7 Accompanying documents . 42
Annex A (normative) Optional functions of the ESPE . 44
Annex B (normative) Catalogue of single faults affecting the electrical equipment of
the ESPE, to be applied as specified in 5.3 . 48
Annex AA (informative) Type 2 AOPD periodic test configurations . 49
Bibliography . 51
Index . 52

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° . 19
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 – Design calculations for a wedge prism . 27
Figure 12 – Example of optical subsystem: Emitter on left – Receiver on right . 27
Figure 13 – Example of SMD LED Model . 28
Figure 14 – Example of intensity distribution of emitting element . 28
Figure 15 – Example of emitter model with beams internally blocked by aperture stop . 28
Figure 16 – Example of receiving unit with off axis beam portion reflected internally on
mechanical elements . 29
Figure 17 – Example of test piece inside model of optical subsystem with passing
radiation on the receiver . 30

61496-2 © IEC:2013 – 3 –
Figure 18 – Example of emitting unit adjusted at the limit . 31
Figure 19 – Extraneous reflection test with mirror outside of limit area . 32
Figure 20 – AOPD misalignment test . 33
Figure 21 – Light interference test – Direct method . 35
Figure 22 – Light interference test – Test set-up with incandescent light source . 36
Figure 23 – Light interference test – Test set-up with fluorescent light source . 37
Figure 24 – Light interference test – Test set-up with flashing beacon light source . 38
Figure 25 – Light interference test – Test set-up with stroboscopic light source . 39
Figure AA.1 – Single beam sensing device . 49
Figure AA.2 – Series connection of single beam sensing devices . 49
Figure AA.3 – Assembly of multiple beams tested individually. 49
Figure AA.4 – Example of type 2 AOPD with internal test . 50

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 4 ESPE
depending on the dimensions of the light curtain . 32

– 4 – 61496-2 © IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF MACHINERY –
ELECTRO-SENSITIVE PROTECTIVE EQUIPMENT –

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

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
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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 61496-2 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 third edition cancels and replaces the second edition published in 2006. It constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Requirements have been corrected and made easier to understand.
b) Test procedures have been revised to make them easier to perform and to improve
repeatability.
c) Guidance is provided for the evaluation and verification of AOPDs using design
techniques for which the test procedures of this part are not sufficient.

61496-2 © IEC:2013 – 5 –
This standard has the status of a product family standard and may 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 61496-1:2012.
This part supplements or modifies the corresponding clauses in IEC 61496-1.
Where a particular clause or subclause of Part 1 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 Part 1 is adapted accordingly.
The text of this standard is based on the following documents:
CDV Report on voting
44/651/CDV 44/670/RVC
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 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 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.
– 6 – 61496-2 © IEC:2013
INTRODUCTION
Electro-sensitive protective equipment (ESPE) is applied to machinery that presents 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 part of IEC 61496 provides particular requirements for the design, construction and
testing of electro-sensitive protective equipment (ESPE) for the safeguarding of machinery,
employing active opto-electronic protective devices (AOPDs) for the sensing function.
Each type of machine presents its own particular hazards, and it is not the purpose of this
standard to recommend the manner of application of the ESPE to any particular machine. The
application of the ESPE should be a matter for agreement between the equipment supplier,
the machine user and the enforcing authority; in this context, attention is drawn to the relevant
guidance established internationally, for example, ISO 12100.
Due to the complexity of the technology of ESPEs there are many issues that are highly
dependent on analysis and expertise in specific test and measurement techniques. In order to
provide a high level of confidence, independent review by relevant expertise is recommended.

61496-2 © IEC:2013 – 7 –
SAFETY OF MACHINERY –
ELECTRO-SENSITIVE PROTECTIVE EQUIPMENT –

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

1 Scope
This clause of Part 1 is replaced by the following:
This part of IEC 61496 specifies requirements for the design, construction and testing of
electro-sensitive protective equipment (ESPE) designed specifically to detect persons as part
of a safety-related system, employing active opto-electronic protective devices (AOPDs) for
the sensing function. Special attention is directed to features which ensure that an
appropriate safety-related performance is achieved. An ESPE may include optional safety-
related functions, the requirements for which are given in Annex A of IEC 61946-1:2012 and
of this part.
This part of IEC 61496 does not specify the dimensions or configurations of the detection
zone and its disposition in relation to hazardous parts for 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.
Excluded from this part are AOPDs employing radiation at wavelengths outside the range
400 nm to 1500 nm.
This part of IEC 61496 may be relevant to applications other than those for the protection of
persons, for example, the protection of machinery or products from mechanical damage. In
those applications, additional requirements may be necessary, for example, when the
materials that are to be recognized by the sensing function have different properties from
those of persons.
This part does of IEC 61496 not deal with EMC emission requirements.
2 Normative references
This clause of Part 1 is applicable except as follows:
Additional references:
IEC 60825-1:2007, Safety of laser products – Part 1: Equipment classification and
requirements
IEC 61496-1:2012, Safety of machinery – Electro-sensitive protective equipment – Part 1:
General requirements and tests
IEC 62471, Photobiological safety of lamps and lamp systems
ISO 13855, Safety of machinery – Positioning of safeguards with respect to the approach
speeds of parts of the human body
EN 471:2003, High-visibility warning clothing for professional use – Test methods and
requirements.
– 8 – 61496-2 © IEC:2013
3 Terms and definitions
NOTE At the end of this standard there is an index which lists, in alphabetical order, the terms and acronyms
defined in Clause 3 and indicates where they are used in the text.
This clause of Part 1 is applicable except as follows:
Additional definitions:
3.201
active opto-electronic protective device
AOPD
device whose sensing function is performed by opto-electronic emitting and receiving
elements detecting the interruption of optical radiations generated, within the device, by an
opaque object present in the specified detection zone (or for a light beam device, on the axis
of the light beam)
Note 1 to entry: This note applies to the French language only.
3.202
beam centre-line
optical path joining the optical centre of an emitting element to the optical centre of the
corresponding receiving element that is intended to respond to light from that emitting
element during normal operation
Note 1 to entry: The optical axis of a light beam is not always on the beam centre-line.
Note 2 to entry: Physical displacement of the beam centre-line may occur as a consequence of normal operation
(for example, by the use of a motor-driven mirror).
Note 3 to entry: For an AOPD that operates on a retro-reflective technique, the optical path is defined by the
retro-reflector target together with the emitting and receiving elements.
3.203
effective aperture angle
EAA
maximum angle of deviation from the optical alignment of the emitting element(s) and the
receiving element(s) within which the AOPD continues in normal operation
Note 1 to entry: This note applies to the French language only.
3.204
light beam device
AOPD comprising one or more emitting element(s) and corresponding receiving element(s),
where a detection zone is not specified by the supplier
3.205
light curtain
AOPD comprising an integrated assembly of one or more emitting element(s) and one or more
receiving element(s) forming a detection zone with a detection capability specified by the
supplier
Note 1 to entry: A light curtain with a large detection capability is sometimes referred to as a light grid.
3.206
test piece
opaque cylindrical element used to verify the detection capability of the AOPD
3.207
geometrically restricted optical design
GROD
AOPD using an optic design where

61496-2 © IEC:2013 – 9 –
– the effective aperture angle (EAA) of each emitting and each receiving element does not
exceed the values given in Figure 6 and
– the axes of the optical beams are parallel and
– side lobes are minimized and
– the spacing between beam centre-lines is uniform and
– the value of detection capability is based on the complete obscuration of at least one
beam for any and all positions of the test piece within the detection zone (see Figure 7).
Note 1 to entry: This note applies to the French language only.
Replacement:
3.3
detection capability
dimension representing the diameter of the test piece which:
– for a light curtain, will actuate the sensing device when placed in the detection zone;
– for a single light beam device, will actuate the sensing device when placed in the beam
centre-line;
– for a multiple light beam device, will actuate the sensing device when placed in any beam
centre-line
Note 1 to entry: The term “detection capability” can also be used to mean the ability to detect a test piece of the
specified diameter.
4 Functional, design and environmental requirements
This clause of Part 1 is applicable except as follows:
4.1 Functional requirements
4.1.2 Sensing function
Replacement:
4.1.2.1 General requirements
The sensing function shall be effective over the detection zone specified by the supplier. No
adjustment of the detection zone, detection capability or blanking function shall be possible
without the use of a key, key-word or tool.
The sensing device of a light curtain shall be actuated and the OSSD(s) shall go to the OFF-
state when a test piece in accordance with 4.2.13 is placed anywhere within the detection
zone either static (at any angle) or moving (with the axis of the cylinder normal to the plane of
the detection zone), at any speed between 0 m/s and 1,6 m/s.
The sensing device of a light beam device shall be actuated and the OSSD(s) shall go to the
OFF-state when a test piece in accordance with 4.2.13 is present in the beam centre-line, at
any point throughout the operating distance, with the axis of the cylinder normal to the axis of
the beam.
NOTE The purpose of this requirement is to ensure that the OSSD(s) go to the OFF-state when a person or part
of a person passes through the detection zone or light beam. Based on a dimension of 150 mm and a walking
speed of 1,6 m/s, a minimum OFF time of 80 ms was determined to be adequate.
When the OSSD(s) go to the OFF-state, they shall remain in the OFF-state while the test
piece is present in the detection zone (or light beam) or for at least 80 ms, whichever is
greater.
– 10 – 61496-2 © IEC:2013
Where the supplier states that an AOPD can be used to detect objects moving at speeds
greater than those specified above, the above requirements shall be met at any speed up to
and including the stated maximum speed(s).
4.1.2.2 Additional requirements for AOPDs using retro-reflective techniques and for
AOPDs using mixed emitters and receivers in the same assembly
4.1.2.2.1 General
AOPDs using retro-reflective techniques where the light beam traverses the detection zone
more than once (over the same path) and AOPDs using mixed emitters and receivers in the
same assembly shall not fail to danger if a reflective object (for example, reflective clothes) is
placed at any position in the detection zone.
NOTE The use of mirrors to return the light beam is not considered to be a retro-reflective technique.
4.1.2.2.2 Sensing function
The OSSD(s) shall go to the OFF-state when a reflective object of a size equal to, or greater
than, the diameter and length of the test piece (see 4.2.13) is placed in the detection zone at
any position as specified in 5.2.1.4.
For a type 4 AOPD, under normal operating conditions, the OSSD(s) shall go to the OFF-state
when a reflective object, as specified in 5.2.1.4 is placed as close as practicable in front of
the sensing surface of the emitting/receiving elements.
4.1.3 Types of ESPE
Replacement:
In this part of IEC 61496, only type 2 and type 4 ESPEs are considered. The types differ in
their performance in the presence of faults and under influences from environmental
conditions. In Part 1, the effects of electrical and electromechanical faults are considered
(such faults are listed in Annex B, Part 1). It is the responsibility of the machine manufacturer
and/or the user to determine which type is required for a particular application.
A type 2 ESPE shall fulfil the fault detection requirements of 4.2.2.3.
For a type 2 ESPE, in normal operation the output circuit of at least one output signal
switching device shall go to the OFF-state when the sensing function is actuated, or when
power is removed from the ESPE.
A type 2 ESPE shall have a means of periodic test.
A type 4 ESPE shall fulfil the fault detection requirements of 4.2.2.5 of IEC 61496-1:2012.
For type 4 ESPE, in normal operation the output circuit of at least two output signal switching
devices shall go to the OFF-state when the sensing function is actuated, or when power is
removed from the ESPE.
When a single safety-related data interface is used to perform the functions of the OSSD(s),
then the data interface and associated safety-related communication interface shall meet the
requirements of 4.2.4.4 of IEC 61496-1:2012. In this case, a single safety-related data
interface can substitute for two OSSDs in a type 4 ESPE.

61496-2 © IEC:2013 – 11 –
4.2 Design requirements
4.2.2 Fault detection requirements
4.2.2.3 Particular requirements for a type 2 ESPE
Addition:
The periodic test shall verify that each light beam operates in the manner specified by the
supplier.
Different configurations are considered that differ in the way the testing of the safety related
performance is carried out.
Annex AA, Figures AA.1, AA.2 and AA.3 are examples of type 2 AOPDs where the periodic
test is externally initiated and the results are externally evaluated. Annex AA, Figure AA.4 is
an example of a type 2 AOPD where the periodic test is automatically initiated and evaluated
internally.
For a type 2 AOPD where the periodic test is internally initiated and evaluated, single faults
that lead to the loss of the automatically initiated internal test shall be detected and shall
result in a lock-out condition.
4.2.2.4 Particular requirements for a type 3 ESPE
This subclause of Part 1 is not applicable.
Additions:
4.2.12 Integrity of the AOPD detection capability
The design of the AOPD shall be such that the AOPD detection capability does not change
from the value stated by the supplier when the AOPD is operated under any and all

combinations of the following:
– any condition within the specification of the supplier;
– the environmental conditions specified in 4.3;
– at the limits of alignment and/or adjustment;
– over the entire detection zone.
If a single fault (as specified in Annex B of IEC 61496-1:2012), which under normal operating
conditions (see 5.1.2.1 of IEC 61496-1:2012) would not result in a loss of AOPD detection
capability but, when occurring with a combination of the conditions specified above, would
result in such a loss, that fault together with that combination of conditions shall be
considered as a single fault, and the AOPD shall respond to such a single fault as required in
4.2.2.
The AOPD shall be designed and constructed to:
a) limit the possibility of failure to danger resulting from extraneous reflections (for operating
range up to 3 m, see Figure 1);
b) limit the misalignment at which normal operation is possible.
For an operating range of 3 m the limits of Figure 2 shall be met;
c) limit the possibility of malfunction during exposure to extraneous light in the range of
400 nm to 1 500 nm.
– 12 – 61496-2 © IEC:2013
35°
d
d
L
IEC  100/13
For type 4: d = 131 mm, L = 250 to 3 000 mm
For type 2: d = 262 mm, L = 500 to 3 000 mm
NOTE In this figure, extraneous reflections from surfaces outside the shaded area will not cause a failure to
danger. For short ranges (250 mm for type 4 and 500 mm for a type 2), the angle of 35° is a limit selected by the
working group based on known designs of AOPDs.
Figure 1 – Limit area for the protection against the risk of beam bypass
If the AOPD is intended to provide protection when mounted very close to a reflective surface
(i.e. inside the shaded area of Figure 1), the AOPD shall be designed in such a manner that
no optical bypassing can occur on the reflective surfaces. For such a device, an EAA much
less than 2,5° (for example, less than 0,1°) can be necessary. In this case, Figure 1 does not
apply and the limits of protection against optical bypassing shall be as specified by the
manufacturer.
61496-2 © IEC:2013 – 13 –
35°
2d
d
d
L
IEC  101/13
For type 4: 2d = 262 mm, L = 3 000 mm
For type 2: 2d = 524 mm, L = 3 000 mm
Figure 2 – Limit of vertical and horizontal misalignment
4.2.13 Test piece
The test piece shall be cylindrical and opaque, with a minimum effective length of 150 mm.
The diameter of the test piece shall not exceed the AOPD detection capability stated by the
supplier.
For AOPDs using retro-reflective techniques and for AOPDs using mixed emitter/receivers in
the same assembly (see 4.1.2.2), the surface of the opaque test piece shall be:
– a retro-reflecting material conforming to the requirements for retro-reflection of
EN 471 class 2 or equivalent;
NOTE Table 5 in EN 471:2003 defines the minimum coefficient of retro-reflection for class 2 material as
-2
-1
330 cd lx m with an entrance angle of 5° and an observation angle of 0,2° (12').
– a mirror-type reflective surface having a reflection factor greater than or equal to 90 % at
the operating wavelength, for example, polished chrome plating or polished aluminium;
– a diffuse reflective surface, white with a coefficient of diffuse reflectance in the range of
80 % to 90 % at the wavelength of the emitter. Example of suitable material is white
paper.
For an AOPD detection capability of not more than 40 mm, the test piece for a light curtain
shall be provided by the supplier and shall be marked with the following:
– diameter in millimetres;
– type reference and an indication of the AOPD with which the test piece is intended to be
used.
When more than one detection capability can be configured on the AOPD, the supplier shall
provide a test piece for each detection capability.

– 14 – 61496-2 © IEC:2013
Verification shall be by inspection.
4.2.14 Wavelength
AOPDs shall operate at a wavelength within the range 400 nm to 1 500 nm.
4.2.15 Radiation intensity
If the emitting device uses LED technology, the radiation intensity generated and emitted by
the AOPD shall meet the requirements of exempt group in accordance to IEC 62471.
NOTE 1 Exempt group is equal to risk group zero (IEC 62471).
If the emitting device uses laser technology, the radiation intensity generated and emitted by
the AOPD shall at no time exceed the accessible emission limits (AEL) for a class 1M device
in accordance with 8.2 of IEC 60825-1:2007.
NOTE 2 Class 2 devices may be used for alignment or adjustment.
4.3 Environmental requirements
Addition:
4.3.5 Light interference
The ESPE shall continue in normal operation when subjected to
– incandescent light;
– flashing beacons;
– fluorescent light operated with high-frequency electronic power supply.
The ESPE shall not fail to danger when subjected to
– incandescent light (simulated daylight using a quartz lamp);
– stroboscopic light;
– fluorescent light operated with high-frequency electronic power supply;
– for a type 4 AOPD, radiation from an emitting assembly (or element ) of identical design.
Combination of technical measures and installation and configuration procedures in
accordance with the information for use provided by the manufacturer shall be tested.
NOTE For type 2 AOPDs the risk of failure to danger from an emitting element of identical design can be reduced
by installation measures supplied by the manufacturer.
These requirements shall be met when the AOPD conforms to the tests in 5.4.6.
No requirements are given for immunity to other extraneous light sources which may cause
abnormal operation or failure to danger. A requirement for the supplier to inform the user of
potential problems is given in (ff) of Clause 7 (in this part and IEC 61496-1:2012).
5 Testing
This clause of Part 1 is applicable except as follows:
5.1 General
Addition:
In the following tests, it shall be verified that when the OSSD(s) go to the OFF-state, they
remain in the OFF-state while the test piece is present in the detection zone (or light beam) or

61496-2 © IEC:2013 – 15 –
for at least 80 ms, whichever is greater. If the AOPD incorporates a restart interlock, the
restart interlock shall be disabled during the tests of this clause.
AOPD may be designed in different ways. The following Table 1 shows the different designs
and corresponding requirements and tests as described within this standard.
Table 1 – Correspondences of requirements/testing and AOPD designs
Different AOPD designs
AOPD using only AOPD using retro- AOPD using emitters
emitters or only reflective techniques and receivers in the
Sub- Requirements receivers in the same same assembly
clause and tests assembly
GROD Unrestricted GROD Unrestricted GROD Unrestricted
optical optical optical
design design design
4.1 Functional
X X X X X X
requirements
4.1.2 Sensing function X X X X X X
4.1.2.2 Additional
requirements for
AOPDs using
retro-reflective
techniques and for
X X X X
AOPDs using
mixed emitters
and receivers in
the same
assembly
4.2 Design
X X X X X X
requirements
4.2.2 Fault detection
X X X X X X
requirements
4.2.12 Integrity of the
AOPD detection X X X X X X
capability
4.2.13 Test piece X X X X X X
4.2.14 Wavelength X X X X X X
4.2.15 Radiation intensity X X X X X X
4.3 Environmental
X X X X X X
requirements
4.3.5 Light interference X X X X X X
5 Testing X X X X X X
5.1 General X X X X X X
5.1.1 Type tests X X X X X X
5.1.1.2 Operating
X X X X X X
condition
5.1.2 Test conditions X X X X X X
5.1.2.2 Measurement
X X X X X X
accuracy
5.2 Functional tests X X X X X X
5.2.1. Sensing function X X X X X X
5.2.1.2.2 Analysis of the
electro-optical X X X X X X
subsystem
– 16 – 61496-2 © IEC:2013
Different AOPD designs
AOPD using only AOPD using retro- AOPD using emitters
emitters or only reflective techniques and receivers in the
Sub- Requirements receivers in the same same assembly
clause and tests assembly
GROD Unrestricted GROD Unrestricted GROD Unrestricted
optical optical optical
design design design
5.2.1.2.3 Verification of the
electro-optical
X X X X X X
subsystem for
GROD
5.2.1.2.4 EAA test of GROD X X X
5.2.1.2.5 Prism test for
X X X
GROD
5.2.1.3 Verification of the
electro-optical
subsystem for X X X
technologies other
than GROD
5.2.1.3.2 Modelling and
verification of
X X X
optical subsystem
model
5.2.1.3.3 Analysis of the
detection
X X X
capability by
simulation
5.2.1.3.4 Additional tests of
detection X X X
capability
5.2.1.3.5 Analysis of
extraneous X X X
reflections
5.2.1.3.6 Extraneous
X X X
reflections test
5.2.1.3.7 Misalignment test X X X
5.2.1.4 Additional tests
for an AOPD using
retro-reflective
techniques and for
X X X X
AOPDs using
mixed emitter and
receivers in the
same assembly
5.4 Environmental
X X X X X X
tests
5.4.6 Light interference X X X X X X
5.4.6.1 General X X X X X X
5.4.6.2 Light sources X X X X X X
5.4.6.3 Test sequences X X X X X X
5.4.6.4 Normal operation
X X X X X X
(best alignment)
5.4.6.5 Failure to danger
– Incandescent
light (3 000 lux X X X X X X
and worst-case
alignment)
61496-2 © IEC:2013 – 17 –
Different AOPD designs
AOPD using only AOPD using retro- AOPD using emitters
emitters or only reflective techniques and receivers in the
Sub- Requirements receivers in the same same assembly
clause and tests assembly
GROD Unrestricted GROD Unrestricted GROD Unrestricted
optical optical optical
design design design
5.4.6.6 Failure to danger
– Stroboscopic
X X X X X X
light (worst-case
alignment)
5.4.6.7 Failure to danger
– Fluorescent light
(3 000 lux and X X X X X X
worst-case
alignment)
5.4.6.8 Failure to danger
– Interfering light
from an emitting X X X X X X
element of
identical design
5.1.1 Type tests
5.1.1.2 Operating condition
Addition:
For the purpose of these tests, the plane of the light curtain detection zone may be either
vertical or horizontal as preferred for a test.
If it can be demonstrated that the results will be the same, testing at long operating distances
may be simulated by the use of neutral density filters.
5.1.2 Test conditions
5.1.2.2 Measurement accuracy
Addition to first paragraph:
– for angular measurement: ± 0,1°;
– for light intensity measurement: ± 10 %.
5.2 Functional tests
5.2.1 Sensing function
Replacement:
5.2.1.1 General
It shall be verified that the sensing device is continuously actuated and, where appropriate,
that the OSSD(s) go to the OFF-state, taking into account the operating principle of the AOPD
and, in particular, the techniques used to provide tolerance to environmental interference.
For a light curtain:
– by slowly moving the test piece in the detection zone across the beams at an angle of 45°
and at an angle of 90° (see Figures 3 and 4) at each end of the detection zone [as near as

– 18 – 61496-2 © IEC:2013
practical to the emitter and receiver (or retro-reflector)] and midway between the ends
(see Figure 5);
– by placing the test piece in the detection zone, stationary, at any position and/or angle
considered critical as a result of the analysis in 5.2.1.2.2
– by moving the test piece in the detection zone, across the beams at the maximum speed
in the range specified in 4.1.2.1, and at any other speed in that range which is considered
critical as a result of the analysis in 5.2.1.2.2;
– by moving the test piece (having a length of 150 mm) through the detection zone at
1,6 m/s such that the direction of movement and the axis of the test piece are normal to
the detection plane, at the extremities of the detection zone (for example, at each corner)
and in any other position that is considered critical as a result of the analysis in 5.2.1.2.2.
For a light beam device:
– by placing the test piece in the beam at each end of the beam and midway along the beam
such that the axis of the test piece is normal to the axis of the beam;
– by moving the test piece (having a length of 150 mm) through the beam at 1,6 m/s such
that the direction of movement and the axis of the test piece are normal to the axis of the
beam, at each end of the beam midway along the beam, and at any point throughout the
operating d
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