IEC 61810-2-1:2017

IEC 61810-2-1 ®
Edition 2.0 2017-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromechanical elementary relays –
Part 2-1: Reliability – Procedure for the verification of B values
Relais électromécaniques élémentaires –
Partie 2-1: Fiabilité – Procédure de vérification des valeurs de B
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IEC 61810-2-1 ®
Edition 2.0 2017-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electromechanical elementary relays –

Part 2-1: Reliability – Procedure for the verification of B values
Relais électromécaniques élémentaires –

Partie 2-1: Fiabilité – Procédure de vérification des valeurs de B
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.70 ISBN 978-2-8322-4389-3

– 2 – IEC 61810-2-1:2017 © IEC 2017
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
3.2 Definitions related to tests . 7
4 Verification of B . 7
4.1 General . 7
4.2 Requirements . 7
4.2.1 Test specimens . 7
4.2.2 Test circuit . 8
4.2.3 Contact loads . 8
4.2.4 Environmental conditions . 8
4.2.5 Operating conditions . 8
4.2.6 Failure criteria . 8
4.3 Performance of the tests . 9
4.3.1 Type test . 9
4.3.2 Routine test . 9
5 Evaluation and verification of B . 9
10D
5.1 General . 9
5.2 Requirements . 10
5.2.1 Test specimens . 10
5.2.2 Test circuit . 10
5.2.3 Contact loads . 11
5.2.4 Environmental conditions . 11
5.2.5 Operating conditions . 11
5.2.6 Failure criteria . 11
5.3 Performance of the tests . 12
5.3.1 Type test . 12
5.3.2 Routine test . 12
Annex A (informative) Example illustrating the assessment of malfunctions for B
10D
evaluation . 15
A.1 Purpose . 15
A.2 Basic assumptions . 15
A.3 Example. 15
A.4 Evaluation . 16
Bibliography . 17

Figure 1 – Schematic flowchart . 13
Figure 2 – Schematic flowchart for relays where dangerous failures have to be
assessed . 14

Table A.1 – Example with number of cycles at which malfunctions have been recorded . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMECHANICAL ELEMENTARY RELAYS –

Part 2-1: Reliability – Procedure for the verification of B values
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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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 61810-2-1 has been prepared by IEC technical committee 94: All-
or-nothing electrical relays.
This second edition cancels and replaces the first edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) limitation of tests to 10 M cycles in Clause 5;
b) reduction of required number of test samples to 5 in specified cases;
c) introduction of WeiBayes analysis for routine test under Clause 4.

– 4 – IEC 61810-2-1:2017 © IEC 2017
The text of this International Standard is based on the following documents:
FDIS Report on voting
94/416/FDIS 94/419/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 International Standard is to be used in conjunction with IEC 61810-2:2017.
A list of all parts in the IEC 61810 series, published under the general title Electromechanical
elementary relays, 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
Based on the general provisions of IEC 61810-2, this part of IEC 61810 specifies reliability
test procedures for electromechanical elementary relays where enhanced requirements for
the verification of reliability apply. A type test is passed and then confirmed by routine tests
with specified periodicity. This document describes how figures for B (the mean number of
cycles until 10 % of the relays have failed) are derived from these life tests performed with
representative relay samples.
In particular when electromechanical elementary relays are intended to be incorporated in
safety-related control systems of machinery in accordance with IEC 62061 and ISO 13849-1,
the mean time to dangerous failure (MTTF ) is a measure that can be taken into account
d
when assessing the probability of dangerous failure of the safety function concerned.
Although a component failure cannot be defined as “dangerous” unless the detailed
application is known, it is common to consider a failure mode that is likely to result in danger
in a typical application of the component, and to refer to this failure mode as a “dangerous
failure”. The MTTF then becomes the expectation of the mean time to failure in this
d
"dangerous" mode. For the calculation of MTTF for electromechanical relays, the data
d
provided by the manufacturer for B can be used (see Clause C.4 of ISO 13849-1:2015).
10D
Electromechanical elementary relays with forcibly guided (mechanically linked) contacts offer
the possibility of a high diagnostic coverage according to 4.5.3 of ISO 13849-1:2015.
NOTE Requirements for such relays are given in IEC 61810-3.

– 6 – IEC 61810-2-1:2017 © IEC 2017
ELECTROMECHANICAL ELEMENTARY RELAYS –

Part 2-1: Reliability – Procedure for the verification of B values
1 Scope
This part of IEC 61810 specifies reliability test procedures for electromechanical elementary
relays when enhanced requirements for the verification of reliability apply.
Particular provisions are given for relays incorporated in safety-related control systems of
machinery in accordance with IEC 62061 and ISO 13849-1. For such relays, B values for
dangerous failures (B values) are derived from the tests specified in this document.
10D
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 61810-1:2015, Electromechanical elementary relays – Part 1: General and safety
requirements
IEC 61810-2:2017, Electromechanical elementary relays – Part 2: Reliability
IEC 61810-3, Electromechanical elementary relays – Part 3: Relays with forcibly guided
(mechanically linked) contacts
IEC 62061, Safety of machinery – Functional safety of safety-related electrical, electronic and
programmable electronic control systems
ISO 13849-1:2015 Safety of machinery – Safety-related parts of control systems – Part 1:
General principles for design
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61810-2 and the
following 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
dangerous failure
failure which has the potential to put the safety-related part of a control system in a hazardous
or fail-to-function state
[SOURCE: ISO 13849-1:2015, 3.1.5, modified – In the definition, the abbreviated term
"SRP/CS" has been replaced by "safety-related part of a control system".]

3.2 Definitions related to tests
3.2.1
type test
conformity test made on sample representative of the production to get basic performance
data or to verify that these relays comply with the specified requirements
[SOURCE: IEC 61810-2:2017, 3.21.1]
3.2.2
routine test
conformity test made on sample without any modifications and specification changes during or
after mass production with specified repetition
Note 1 to entry: The results from routine tests are used to verify that the level of technical performance is
maintained.
[SOURCE: IEC 61810-2:2017, 3.21.2, modified – The note has been added.]
4 Verification of B
4.1 General
Clause 4 specifies requirements where the reliability of the relay has to be assessed and
verified.
This procedure is applicable to relays where wearout mechanisms prevail.
NOTE 1 For relays where random failures prevail, provisions are under consideration.
NOTE 2 For relays intended to be used in safety-related control systems of machinery, the provisions of Clause 5
are applicable.
The following failure modes can occur:
• failure to open of a relay contact;
• failure to close of a relay contact;
• unintended bridging of a change-over contact;
• insulation failure of the relay.
From a type test, a value for B is obtained that indicates the probability of the occurrence of
a relay failure. The value for B is given in numbers of cycles.
NOTE 3 With the knowledge of the frequency of operation (cycling rate) of the relay within a specific application,
the number of cycles can be transformed into respective times.
Verification that this B value is applicable to relays from the series production shall be
carried out by routine tests.
An overview of this procedure is given in Figure 1.
4.2 Requirements
4.2.1 Test specimens
The test shall be carried out in accordance with IEC 61810-2.

– 8 – IEC 61810-2-1:2017 © IEC 2017
4.2.2 Test circuit
The test circuit described in Annex C of IEC 61810-1:2015 shall be used, unless otherwise
specified by the manufacturer and explicitly indicated in the test report. When feasible, one of
the circuits in accordance with Annex D of IEC 61810-1:2015 is to be used.
4.2.3 Contact loads
The contact loads shall be specified by the manufacturer and indicated in the test report. It is
recommended to select appropriate resistive loads according to 5.8 of IEC 61810-1:2015 or
inductive loads according to Annex B of IEC 61810-1:2015.
4.2.4 Environmental conditions
The conditions of Table 1 of IEC 61810-1:2015 apply. However, an extended ambient
temperature range of 18 °C to 40 °C is permitted.
4.2.5 Operating conditions
The provisions of 5.3 of IEC 61810-2:2017 apply.
Unless otherwise specified by the manufacturer, each cycle of the coil energization shall be
1 s ON and 9 s OFF.
The test is performed without coil suppression, unless explicitly specified.
4.2.6 Failure criteria
Generally, the test is to be continued until all test specimens have failed. When the test is
truncated at a specific number of cycles, all relays that have not yet failed are considered to
fail at that number of cycles (worst case assumption). However, at least 2/3 of the tested
relays shall fail, or each test specimen shall reach a lifetime of 10 M cycles.
For the assessment of recorded malfunctions severity B according to Clause 6 of
IEC 61810-2:2017 applies. The dielectric test is performed
• between coil and contacts,
• between adjacent contacts, and
• across open contacts.
A contact that fails to open cannot be tested for compliance with the requirements for open
contacts.
The insulation requirements shall be verified according to 11.4 of IEC 61810-1:2015. This may
be performed in either of the following ways.
a) During the test, the dielectric test is performed periodically at given numbers of cycles.
When the relay does not pass the dielectric test, the number of cycles for the previous
dielectric test that has been passed is considered as the cycles to failure value for this
individual relay.
b) In the case that no periodical monitoring according to item a) is performed, the dielectric
test shall be made when a relay under test fails due to a functional contact failure
(see 4.1). If the relay does not comply with the dielectric test, the whole test is not passed.
The same applies when the test is truncated at a certain number of cycles.

4.3 Performance of the tests
4.3.1 Type test
The type test is carried out with a sample of 10 relays. Each failure shall be recorded.
The B value is evaluated based on the procedure given in IEC 61810-2. For the purpose of
the following routine test according to 4.3.2.3, the shape parameter β and the characteristic
life shall be evaluated according to IEC 61810-2.
η
After completion of a type test, the first routine test shall be initiated for verification in
accordance with the periodicity specified under 4.3.2.
4.3.2 Routine test
4.3.2.1 General
The routine test shall be performed in regular intervals as specified by the manufacturer.
4.3.2.2 Routine test with Weibull
The test shall be performed with at least 5 relays, and B value shall be determined in
accordance with IEC 61810-2.
4.3.2.3 Routine test with WeiBayes
The test shall be performed with at least 5 relays, and B value shall be determined in
accordance with IEC 61810-2. In the event of deviation from 4.2.6, the test is stopped with no
failures recorded (WeiBayes without failure), and a WeiBayes confidence level of 90 % shall
be achieved.
4.3.2.4 Acceptance criteria of routine test
For each routine test, the evaluated B value shall be at least 80 % of the B value obtained
10 10
from the type test. For the routine test with WeiBayes, the B value obtained shall be at least
90 % of that of the type test.
NOTE 1 This requirement is intended to take into account possible variations for the routine tests.
NOTE 2 In IEC 61810-2 the WeiBayes result is determined using the characteristic life result from the initial
Weibull test. Accordingly, here the acceptance of the routine test can be evaluated by comparing the characteristic
life values of the initial Weibull and the WeiBayes from the routine test.
In the event that these requirements are not met, suitable corrective actions have to be taken
to remove the failure causes. The routine test shall be repeated with appropriately modified
test specimens. If it is not possible to achieve a positive routine test with non-constructive
corrective actions, constructional changes to the relay (e.g. new contact material, dimensional
changes of contact) are necessary, and the modified relay shall be regarded as a new
construction, and a new independent test procedure starting a with type test shall be
performed.
5 Evaluation and verification of B
10D
5.1 General
Clause 5 specifies requirements for relays intended to be used in safety-related control
systems of machinery in accordance with IEC 62061 and ISO 13849-1. For this purpose,
Clause 4 does not apply.
This procedure is applicable to relays where wearout mechanisms prevail.

– 10 – IEC 61810-2-1:2017 © IEC 2017
NOTE 1 For relays where random failures prevail, provisions are under consideration.
The following failure modes can occur:
• failure to open of a relay contact;
• failure to close of a relay contact;
• unintended bridging of a change-over contact;
• insulation failure of the relay.
NOTE 2 The term “unintended bridging of a changeover contact” is equivalent to “simultaneous short-circuit
between the three terminals of a changeover contact” (used in Table D.9 of ISO 13849-2:2012).
For a given application, it has to be assessed which of the above-listed failure mode(s) is
(are) to be considered as dangerous failure(s).
Simultaneous closing of make contacts and break contacts is excluded if forcibly guided
(mechanically linked) contacts are used which offer the possibility of a high diagnostic
coverage according to 4.5.3 of ISO 13849-1:2015. Electromechanical elementary relays with
forcibly guided (mechanically linked) contacts are specified in IEC 61810-3.
NOTE 3 In typical applications, the failure to open of a make contact and the insulation failure are dangerous
failure modes (see 7.2.2 and Table D.1 of ISO 13849-2:2012, where basic safety principles are compiled, in
particular the use of de-energisation with a normally open (make) contact for relays to achieve a system safe
state).
Where it is not clear which failure mode is to be considered as a dangerous failure, the
manufacturer shall record during the test any malfunction (in number of cycles and type of
malfunction). This allows them to evaluate B values for any failure mode after the test has
been completed.
From a type test, a value for B is obtained that indicates the probability of the occurrence
10D
of a dangerous failure. This value is given in number of cycles.
NOTE 4 With the knowledge of the frequency of operation (cycling rate) of the relay within a specific application,
the number of cycles can be transformed into respective times.
Verification that these B values are applicable to relays from the series production shall be
10D
carried out by routine tests.
An overview of this procedure is given in Figure 2.
5.2 Requirements
5.2.1 Test specimens
The test shall be carried out for each contact load rating in accordance with IEC 61810-2. In
the case of relays with several contacts, those two contacts – of the same type (e.g. two make
contacts) if available – shall be tested which are considered as most critical with respect to a
possible insulation failure.
NOTE In general, adjacent contacts are the most critical ones.
5.2.2 Test circuit
The test circuit described in Annex C of IEC 61810-1:2015 shall be used, unless otherwise
specified by the manufacturer and explicitly indicated in the test report. When feasible, one of
the circuits in accordance with Annex D of IEC 61810-1:2015 is to be used.

5.2.3 Contact loads
The contact loads shall be specified by the manufacturer and indicated in the test report. It is
recommended to select load types according to Annex B (endurance test) of
IEC 61810-1:2015. Unless otherwise specified, the type test shall be carried out for an AC
inductive load with 230 V and for a DC inductive load with 24 V with the following load
currents:
• I ;
e
• I /2;
e
• I /4;
e
where I = rated operating current.
e
The test with I /4 can be omitted. In this case, the B value for a smaller load than I /2 shall
e 10 e
be derived through linear interpolation of the B results at I and I /2 in a log-log graph.
10 e e
NOTE In general, the routine test is carried out with I only (see 5.3.2).
e
5.2.4 Environmental conditions
The conditions of Table 1 of IEC 61810-1:2015 apply. However, an ambient temperature
range of 18 °C to 40 °C is permitted.
5.2.5 Operating conditions
The provisions of 5.3 of IEC 61810-2:2017 apply.
Unless otherwise specified by the manufacturer, each cycle of the coil energisation shall be
1 s ON and 9 s OFF.
The test is performed without coil suppression, unless explicitly specified.
5.2.6 Failure criteria
The test shall be continued until all test specimens have failed or reached a lifetime of 10 M
cycles.
For the assessment of recorded malfunctions in accordance with Clause 6 of
IEC 61810-2:2017, the following applies:
• for malfunctions related to a dangerous failure mode: severity A;
• for other malfunctions: severity B.
The verification of insulation requirements according to Clause 11 of IEC 61810-1:2015 (with
100 % of the initial voltage for the dielectric test specified under 10.2 of IEC 61810-1:2015)
shall be performed when a relay under test fails due to a functional contact failure (see 5.1).
The dielectric test is performed
• between coil and contacts,
• between adjacent contacts, and
• across open contacts.
NOTE A contact that fails to open cannot be tested for compliance with the requirements for open contacts.
If the relay does not comply with the dielectric test, the whole test is not passed.

– 12 – IEC 61810-2-1:2017 © IEC 2017
5.3 Performance of the tests
5.3.1 Type test
The type test is carried out with a sample of 10 relays for each contact load rating. Each
failure shall be recorded. The dangerous failures are registered separately.
In the first step, the B value is evaluated based on the procedure given in IEC 61810-2
taking into account all registered failures (see also Annex A for a schematic example).
The B value is derived as follows:
10D
B = B × 10/N
10D 10 D
where
10 is the number of tested relays;
N is the number of registered dangerous failures.
D
When no dangerous failure has been registered, N = 1 is assumed.
D
EXAMPLE From data obtained with a life test of 10 relays, a B value has been derived:
B = 6 × 10 cycles
10D
During the test, 3 relays were registered with dangerous failures. Then the following estimation for B is
calculated:
10D 10 5 6
B = B × 10/3 = 6 × 10 × 10/3 = 2 × 10 cycles
The type test yields 3 different values of B for I , I /2 and I /4, each for AC inductive and
10D e e e
DC inductive loads.
After completion of a type test, the first routine test shall be initiated for verification in
accordance with the periodicity specified under 5.3.2.
5.3.2 Routine test
The routine test shall be performed with minimum 5 relays in regular intervals as specified by
the manufacturer, as a minimum with the rated operating current I only.
e
It is recommended to perform the routine test for each load every two years. This allows the
manufacturer to perform alternate tests with either an AC or a DC inductive load once a year.
The total number of dangerous failures during the routine test shall be evaluated based on the
value N registered during the type test. It shall be smaller than or equal to (N + 2) n’/10,
D D
where n’ is the number of relays tested in the routine test.
For each routine test, the evaluated B value shall be at least 80 % of the B value obtained
10 10
from the type test.
NOTE This requirement is intended to take into account possible variations for the routine tests.
In the case that these requirements are not met, suitable corrective actions have to be taken
to remove the failure causes. The routine test shall be repeated with appropriately modified
test specimens. If it is not possible to achieve a positive routine test, corrective actions (e.g.
constructional changes to the relay, new contact material, dimensional changes of contact)
are necessary, and the modified relay shall be regarded as a new construction, and a new,
independent test procedure shall be performed.

Take appropriate
Start routine test
Start type test corrective
measures
Life test
Life test
(same as for type test)
with specified contact load
Determine cause
B value for the relay
according to IEC 61810-2
No
B10’ ≥ B10 × 0,8
Yes
Following the type test, the first
routine test shall be performed
to verify the type test
Test passed
B = B value obtained from type test
10 10
B ’ = B value obtained from routine test
10 10
IEC
Figure 1 – Schematic flowchart

– 14 – IEC 61810-2-1:2017 © IEC 2017
Take appropriate
corrective
Start type test Start routine test
measures
Life test
Life test:
with I
e
each with I , I /2 and I /4
e e e
No
N ’ ≤ (N + 2) ×
D D
Determine cause
n’ / 10
Yes
B10 value for the relay
according to IEC 61810-2
No
B ’ ≥ B × 0,8
10 10
B = 10 / N × B
10D
D 10
Yes
(1 ≤ N )
D
Test passed
Following the type test, the
first routine test shall be
performed to verify the type
test
IEC
Key
Number of dangerous failures during the type test
N
D
N Number of dangerous failures during the routine test
D’
B B value obtained from the type test
B B value obtained from the routine test
B B value obtained from the type test
10D
10D
n’ Number of relays tested in the routine test

NOTE The type test yields 3 results:
B for I
10D e
B for I /2
10D e
B for I /4
10D e
Figure 2 – Schematic flowchart for relays where
dangerous failures have to be assessed

Annex A
(informative)
Example illustrating the assessment of malfunctions
for B evaluation
10D
A.1 Purpose
Annex A contains a schematic example that is intended to illustrate the application of the
provisions contained in Clause 5 for deriving relay failure data to be used for the estimation of
B .
10D
NOTE The given values for cycles until malfunction/failure are just arbitrary figures to describe the procedures,
not figures obtained from real tests.
A.2 Basic assumptions
In this example 10 relays are submitted to the life test. It is assumed that the failure to open
of a relay contact is a dangerous failure. The failure to close is a non-dangerous failure.
Insulation failures do not occur in this example.
For malfunctions related to failure to open (dangerous failure mode), the first malfunction
causes a relay failure (severity A).
For malfunctions related to failure to close (non-dangerous failure mode), two consecutive
malfunctions or a total of six malfunctions cause a relay failure (severity B).
A.3 Example
In Table A.1, the number of cycles at which malfunctions have occurred are listed for 4 out of
10 specimens.
Table A.1 – Example with number of cycles
at which malfunctions have been recorded
Specimen Number of cycles Case
Malfunction no.
1 2 3 4 5 6
1 73 679 ↓   a
2 50 001 50 003  b
53 505 ↓
3 74 902 75 047 77 834 77 835 ↓  c
… … … … … … … …
10 44 967 45 024 45 239 45 343 45 402 45 478 ↓ d
Data for B 73 679 53 505 77 835 45 478
NOTE Bold type indicates that this malfunction results in a dangerous failure.

– 16 – IEC 61810-2-1:2017 © IEC 2017
Case a: the first malfunction is due to a failure to open, and therefore causes a dangerous
failure (severity A).
Case b: the third malfunction is due to a failure to open, and therefore causes a dangerous
failure (severity A). The preceding malfunctions are due to failures to close (non-dangerous
failure mode) that did not result in a relay failure.
Case c: two consecutive malfunctions due to failures to close (non-dangerous failure mode)
cause a relay failure (severity B).
th
Case d: the 6 observed malfunction (all due to failures to close – non-dangerous failure
mode) results in a relay failure (severity B).
The resulting numbers of cycles for the failure of each of the four relay specimens are filled in
the bottom line of Table A.1.
A.4 Evaluation
The numbers of cycles at which the relay specimens failed are used to obtain the B value
following the procedures of IEC 61810-2.
Finally, the value for B is derived from this B value as given in 5.3.1.
10D 10
Bibliography
ISO 13849-2:2012, Safety of machinery – Safety-related parts of control systems – Part 2:
Validation
___________
– 18 – IEC 61810-2-1:2017 © IEC 2017
SOMMAIRE
AVANT-PROPOS . 19
INTRODUCTION . 21
1 Domaine d'application . 22
2 Références normatives . 22
3 Termes et définitions . 22
3.2 Définitions relatives aux essais . 23
4 Vérification de B . 23
4.1 Généralités . 23
4.2 Exigences . 24
4.2.1 Éprouvettes . 24
4.2.2 Circuit d'essai . 24
4.2.3 Charges de contact. 24
4.2.4 Conditions d'environnement . 24
4.2.5 Conditions de fonctionnement . 24
4.2.6 Critères de défaillance . 24
4.3 Réalisation des essais . 25
4.3.1 Essai de type . 25
4.3.2 Essai individuel de série . 25
5 Évaluation et vérification de B . 26
10D
5.1 Généralités . 26
5.2 Exigences . 27
5.2.1 Éprouvettes . 27
5.2.2 Circuit d'essai . 27
5.2.3 Charges de contact. 27
5.2.4 Conditions d'environnement . 27
5.2.5 Conditions de fonctionnement . 27
5.2.6 Critères de défaillance . 27
5.3 Réalisation des essais . 28
5.3.1 Essai de type . 28
5.3.2 Essai individuel de série . 28
Annexe A (informative) Exemple représentatif de l'évaluation des dysfonctionnements
pendant l'évaluation de B . 31
10D
A.1 Objet . 31
A.2 Hypothèses de base .
...