SIST EN 60068-2-6:2008
Environmental testing -- Part 2-6: Tests - Test Fc: Vibration (sinusoidal)
Environmental testing -- Part 2-6: Tests - Test Fc: Vibration (sinusoidal)
This part of IEC 60068 gives a method of test which provides a standard procedure to determine the ability of components, equipment and other articles, hereinafter referred to as specimens, to withstand specified severities of sinusoidal vibration. If an item is to be tested in an unpackaged form, that is without its packaging, it is referred to as a test specimen. However, if the item is packaged then the item itself is referred to as a product and the item and its packaging together are referred to as a test specimen. The purpose of this test is to determine any mechanical weakness and/or degradation in the specified performance of specimens and to use this information, in conjunction with the relevant specification, to decide upon the acceptability of the specimens. In some cases, the test method may also be used to demonstrate the mechanical robustness of specimens and/or to study their dynamic behaviour. Categorization of components can also be made on the basis of a selection from within the severities quoted in the test.
Umgebungseinflüsse - Teil 2-6: Prüfverfahren - Prüfung Fc: Schwingen (sinusförmig)
Essais d'environnement -- Partie 2-6: Essais - Essai Fc: Vibrations (sinusoïdales)
Fournit une méthode d'essai qui donne des règles d'exécution normalisées pour déterminer l'aptitude des composants, matériels et autres articles ci-après désignés 'spécimens', à résister à des sévérités spécifiées de vibrations sinusoïdales. S'il est prevu de soumettre un objet aux essais en étant non emballé, sans son emballage, il est désigné comme un spécimen d'essai. Cependant, si l'objet est emballé, alors l'objet lui-même est désigné comme produit et l'objet ainsi que son emballage sont désignés comme spécimen d'essai. L'objet de cet essai est de déterminer les faiblesses mécaniques et/ou les dégradations des performances spécifiées des spécimens, et d'utiliser ces renseignements conjointement avec la spécification particulière pour décider si un spécimen est acceptable ou non. Dans certains cas, la méthode d'essai peut également être utilisée pour démontrer la robustesse mécanique d'un spécimen et/ou pour étudier son comportement dynamique. La classification des composants en catégories peut également se faire sur la base d'une sélection faite à partir des sévérités données dans l'essai. Les modifications principales par rapport à l'édition précédente sont les suivantes: - Référence à la dernière version de la CEI 60068 2 47: Fixation. - Simplification de la mise en page de la norme en remplaçant quelques tableaux par du texte. - Ajout d'exigences sur le rapport d'essai (voir Article 13).
Okoljski preskusi - 2-6. del: Preskusi - Preskus Fc: Vibracije (sinusne) (IEC 60068-2-6:2007)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 60068-2-6:2008
01-junij-2008
1DGRPHãþD
SIST EN 60068-2-6:2001
Okoljski preskusi - 2-6. del: Preskusi - Preskus Fc: Vibracije (sinusne) (IEC 60068-2
-6:2007)
Environmental testing - Part 2-6: Tests - Test Fc: Vibration (sinusoidal)
Umgebungseinflüsse - Teil 2-6: Prüfverfahren - Prüfung Fc: Schwingen (sinusförmig)
Essais d'environnement -- Partie 2-6: Essais - Essai Fc: Vibrations (sinusoïdales)
Ta slovenski standard je istoveten z: EN 60068-2-6:2008
ICS:
19.040 Preskušanje v zvezi z Environmental testing
okoljem
SIST EN 60068-2-6:2008 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 60068-2-6
NORME EUROPÉENNE
February 2008
EUROPÄISCHE NORM
ICS 19.040 Supersedes EN 60068-2-6:1995
English version
Environmental testing -
Part 2-6: Tests -
Test Fc: Vibration (sinusoidal)
(IEC 60068-2-6:2007)
Essais d'environnement - Umgebungseinflüsse -
Partie 2-6: Essais - Teil 2-6: Prüfverfahren -
Essai Fc: Vibrations (sinusoïdales) Prüfung Fc: Schwingen (sinusförmig)
(CEI 60068-2-6:2007) (IEC 60068-2-6:2007)
This European Standard was approved by CENELEC on 2008-02-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60068-2-6:2008 E
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EN 60068-2-6:2008 - 2 -
Foreword
The text of document 104/439/FDIS, future edition 7 of IEC 60068-2-6, prepared by IEC TC 104,
Environmental conditions, classification and methods of test, was submitted to the IEC-CENELEC parallel
vote and was approved by CENELEC as EN 60068-2-6 on 2008-02-01.
This European Standard supersedes EN 60068-2-6:1995.
The major changes with regard to EN 60068-2-6:1995 concern:
– the agreed wording from IEC technical committee 104 meeting held in Stockholm:2000 on the testing
of soft packages;
– reference to the latest version of EN 60068-2-47: Mounting;
– simplification of the layout of the standard by replacing some tables with text;
– addition of the test report requirements (see Clause 13).
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2008-11-01
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2011-02-01
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60068-2-6:2007 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 60068-2-64 NOTE Harmonized as EN 60068-2-64:1994 (not modified).
__________
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- 3 - EN 60068-2-6:2008
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following referenced documents are indispensable for the application 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.
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60068-1 - Environmental testing - EN 60068-1 1994
Part 1: General and guidance
1) 2)
IEC 60068-2-47 - Environmental testing - EN 60068-2-47 2005
Part 2-47: Tests - Mounting of specimens for
vibration, impact and similar dynamic tests
IEC 60721-3 Series Classification of environmental conditions - EN 60721-3 Series
Part 3: Classification of groups of
environmental parameters and their severities
1)
ISO 2041 - Vibration and shock - Vocabulary - -
ISO/IEC 17025 2005 General requirements for the competence of EN ISO/IEC 17025 2005
testing and calibration laboratories
1)
Undated reference.
2)
Valid edition at date of issue.
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IEC 60068-2-6
Edition 7.0 2007-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Environmental testing –
Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
Essais d'environnement –
Partie 2-6: Essais – Essai Fc: Vibrations (sinusoïdales)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
X
CODE PRIX
ICS 19.040 ISBN 2-8318-9490-5
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CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references.7
3 Terms and definitions .7
4 Requirements for testing.10
4.1 Required characteristics .10
4.1.1 Basic motion.10
4.1.2 Spurious motion.10
4.1.3 Signal tolerance.11
4.1.4 Vibration amplitude tolerances .11
4.1.5 Frequency tolerances.11
4.1.6 Sweep .12
4.2 Control strategy .12
4.2.1 Single/multipoint control.12
4.2.2 Multi-reference control .13
4.3 Mounting .13
5 Severities .13
5.1 Frequency range.14
5.1.1 Lower frequency f Hz .14
1
5.1.2 Upper frequency f Hz .14
2
5.2 Vibration amplitude.14
5.3 Duration of endurance .17
5.3.1 Endurance by sweeping .17
5.3.2 Endurance at fixed frequencies .18
6 Preconditioning.18
7 Initial measurements.18
8 Testing .18
8.1 General .18
8.2 Vibration response investigation.19
8.3 Endurance procedures.19
8.3.1 Endurance by sweeping .19
8.3.2 Endurance at fixed frequencies .19
9 Intermediate measurements.20
10 Recovery .20
11 Final measurements .20
12 Information to be given in the relevant specification.20
13 Information to be given in the test report .21
23
Annex A (informative) Guide to test Fc .
Annex B (informative) Examples of severities primarily intended for components .36
Annex C (informative) Examples of severities primarily intended for equipment.37
Bibliography .39
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60068-2-6 © IEC:2007 – 3 –
Figure 1 – Nomogram relating vibration amplitude to frequency with lower cross-over
frequency (8 Hz to 10 Hz).15
Figure 2 – Nomogram relating vibration amplitude to frequency with higher cross-over
16
frequency (58 Hz to 62 Hz).
Figure 3 – Nomogram relating vibration displacement amplitude to frequency (only
applicable for frequency ranges with an upper frequency of 10 Hz) .17
Figure A.1 – Generalized transmissibility factors for vibration isolators.33
Table A.1 – Number of sweep cycles and associated endurance times per axis .30
Table A.2 – CB response time .31
Table A.3 – CPB response time.32
Table B.1 – Endurance by sweeping – Examples with higher cross-over frequency .36
Table C.1 – Endurance by sweeping – Examples with lower cross-over frequency .37
Table C.2 – Endurance by sweeping – Examples with higher cross-over frequency .38
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– 4 – 60068-2-6 © IEC:2007
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENVIRONMENTAL TESTING –
Part 2: Tests – Test Fc: Vibration (sinusoidal)
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 60068-2-6 has been prepared by IEC technical committee 104:
Environmental conditions, classification and methods of test.
This seventh edition cancels and replaces the sixth edition, published in 1995. It consitutes a
technical revision.
The major changes with regard to the previous edition concern:
⎯ The agreed wording from IEC technical committee 104 meeting held in Stockholm:2000
on the testing of soft packages.
⎯ Reference to the latest version of IEC 60068-2-47:Mounting
⎯ Simplification of the layout of the standard by replacing some tables with text.
⎯ Addition of the test report requirements (see Clause 13).
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60068-2-6 © IEC:2007 – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
104/439/FDIS 104/449/RVD
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 the parts in the IEC 60068 series, under the general title Environmental testing, can
be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until the
maintenance result 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.
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– 6 – 60068-2-6 © IEC:2007
INTRODUCTION
This part of IEC 60068 gives a method of test applicable to components, equipment and other
articles which, during transportation or in service, may be subjected to conditions involving
vibration of a harmonic pattern, generated primarily by rotating, pulsating or oscillating forces,
such as occur in ships, aircraft, land vehicles, rotorcraft and space applications or are caused
by machinery and seismic phenomena.
This standard consists basically of subjecting a specimen to sinusoidal vibration over a given
frequency range or at discrete frequencies, for a given period of time. A vibration response
investigation may be specified which aims at determining critical frequencies of the specimen.
The relevant specification shall indicate whether the specimen shall function during vibration or
whether it suffices that it still works after having been submitted to vibration.
It is emphasized that vibration testing always demands a certain degree of engineering
judgement, and both the supplier and purchaser should be fully aware of this fact. However,
sinusoidal testing is deterministic and, therefore, relatively simple to perform. Thus it is readily
applicable to both diagnostic and service life testing.
The main part of this standard deals primarily with the methods of controlling the test at
specified points using either analogue or digital techniques, and gives, in detail, the testing
procedure. The requirements for the vibration motion, choice of severities including frequency
ranges, amplitudes and endurance times are also specified, these severities representing a
rationalized series of parameters. The relevant specification writer is expected to choose the
testing procedure and values appropriate to the specimen and its use.
Certain terms have been defined to facilitate a proper understanding of the text. These
definitions are given in Clause 3.
Annex A gives general guidance for the test and Annexes B and C provide guidance on the
selection of severities for components and equipment.
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60068-2-6 © IEC:2007 – 7 –
ENVIRONMENTAL TESTING –
Part 2: Tests – Test Fc: Vibration (sinusoidal)
1 Scope
This part of IEC 60068 gives a method of test which provides a standard procedure to
determine the ability of components, equipment and other articles, hereinafter referred to as
specimens, to withstand specified severities of sinusoidal vibration. If an item is to be tested in
an unpackaged form, that is without its packaging, it is referred to as a test specimen.
However, if the item is packaged then the item itself is referred to as a product and the item
and its packaging together are referred to as a test specimen.
The purpose of this test is to determine any mechanical weakness and/or degradation in the
specified performance of specimens and to use this information, in conjunction with the
relevant specification, to decide upon the acceptability of the specimens. In some cases, the
test method may also be used to demonstrate the mechanical robustness of specimens and/or
to study their dynamic behaviour. Categorization of components can also be made on the basis
of a selection from within the severities quoted in the test.
2 Normative references
The following referenced documents are indispensable for the application 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 60068-1, Environmental testing – Part 1: General and guidance
IEC 60068-2-47, Environmental testing – Part 2-47: Tests – Mounting of specimens for
vibration, impact and similar dynamic tests
IEC 60721-3 (all parts), Classification of environmental conditions – Part 3: Classification of
groups of environmental parameters and their severities
ISO 2041, Vibration and shock – Vocabulary
ISO/IEC 17025:2005, General requirements for the competence of testing and calibration
laboratories
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
NOTE 1 The terms used are generally taken from ISO 2041 and IEC 60068-1. However, “sweep cycle” (3.4) and
“signal tolerance” (3.5) have specific meanings in this standard.
Definitions in alphabetical order:
Actual motion 3.7
Basic motion 3.6
Centred resonance frequency 3.10
Check point 3.2.1
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Critical frequencies 3.9
Damping 3.8
Fictitious reference point 3.2.3
Fixing point 3.1
g 3.12
n
Measuring points 3.2
Multipoint control 3.3.2
Reference point 3.2.2
Restricted frequency sweeping 3.11
Signal tolerance 3.5
Single point control 3.3.1
Sweep cycle 3.4
NOTE 2 Terms described below are either not identical to, or not defined in ISO 2041 or in IEC 60068-1.
3.1
fixing point
part of the specimen in contact with the fixture or vibration table at a point where the specimen
is normally fastened in service
NOTE 1 If a part of the real mounting structure is used as the fixture, the fixing points are those of the mounting
structure and not of the specimen.
NOTE 2 Where the specimen consists of a packaged product, fixing point may be interpreted as the surface of the
specimen which is in contact with the vibration table.
3.2
measuring points
specific points at which data are gathered conducting the test
NOTE 1 These are of two main types, the definitions of which are given below.
NOTE 2 Measurements may be made at points within the specimen in order to assess its behaviour, but these are
not considered as measuring points in the sense of this standard. For further details, see A.2.1.
3.2.1
check point
point located on the fixture, on the vibration table or on the specimen as close as possible to
one of its fixing points, and in any case rigidly connected to it
NOTE 1 A number of check points are used as a means of ensuring that the test requirements are satisfied.
NOTE 2 If four or fewer fixing points exist, each is used as a check point. For packaged products, where a fixing
point may be interpreted as the packaging surface in contact with the vibration table, one check point may be used,
provided that there are no effects due to resonances of the vibration table or the mounting structure in the
frequency range specified for the test. If this is the case, multipoint control may be necessary, but see also Note 3.
If more than four fixing points exist, four representative fixing points will be defined in the relevant specification to
be used as check points.
NOTE 3 In special cases, for example for large or complex specimens, the check points will be prescribed in the
relevant specification if not close to the fixing points.
NOTE 4 Where a large number of small specimens are mounted on one fixture, or in the case of a small specimen
where there are several fixing points, a single check point (i.e. the reference point) may be selected for the
derivation of the control signal. This signal is then related to the fixture rather than to the fixing points of the
specimen(s). This is only valid when the lowest resonance frequency of the loaded fixture is well above the upper
frequency of the test.
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60068-2-6 © IEC:2007 – 9 –
3.2.2
reference point
point, chosen from the check points, whose signal is used to control the test, so that the
requirements of this standard are satisfied
3.2.3
fictitious reference point
point, derived from multiple check points, either manually or automatically, the result of which
is used to control the test, so that the requirements of this standard are satisfied
3.3
control methods
3.3.1
single point control
control method using the signal from the transducer at the reference point in order to maintain
this point at the specified vibration level (see 4.1.4.1)
3.3.2
multipoint control
control method achieved by using the signals from each of the transducers at the check points
NOTE The signals are either continuously averaged arithmetically or processed by using comparison techniques,
depending upon the relevant specification (see 4.1.4.1)
3.4
sweep cycle
traverse of the specified frequency range once in each direction, for example 10 Hz to 150 Hz
to 10 Hz
NOTE Manufacturers' handbooks for digital sine control systems often refer to a sweep cycle as f to f , and not f
1 2 1
to f to f .
2 1
3.5
signal tolerance
NF
⎛ ⎞
signal tolerance T = −1 × 100 %
⎜ ⎟
⎝ ⎠
F
where
NF is the r.m.s value of the unfiltered signal;
F is the r.m.s value of the filtered signal.
NOTE This parameter applies to whichever signal, i.e. acceleration, velocity or displacement, is being used to
control the test (see A.2.2).
3.6
basic motion
motion at the driving frequency of vibration at the reference point (see also 4.1.1)
3.7
actual motion
motion represented by the wideband signal returned from the reference point transducer
3.8
damping
generic term ascribed to the numerous energy dissipation mechanisms in a system
NOTE In practice, damping depends on many parameters, such as the structural system, mode of vibration,
strain, applied forces, velocity, materials, joint slippage, etc.
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3.9
critical frequencies
frequencies at which
– malfunctioning and/or deterioration of performance of the specimen are exhibited which
are dependent on vibration, and/or
– mechanical resonances and/or other response effects occur, for example, chatter
3.10
centred resonance frequency
frequency automatically centred on the actual resonance frequency derived from the vibration
response investigation
3.11
restricted frequency sweeping
sweeping over a restricted frequency range between 0,8 and 1,2 times the critical frequency
3.12
g
n
standard acceleration due to the earth's gravity, which itself varies with altitude and
geographical latitude
NOTE For the purposes of this standard, the value of g is rounded up to the nearest whole number, that is
n
2
10 m/s .
4 Requirements for testing
4.1 Required characteristics
The required characteristics apply to the complete vibration system, which includes the power
amplifier, vibrator, test fixture, specimen and control system when loaded for testing.
4.1.1 Basic motion
The basic motion shall be a sinusoidal function of time and such that the fixing points of the
specimen move substantially in phase and in straight parallel lines, subject to the limitations of
4.1.2 and 4.1.3.
4.1.2 Spurious motion
4.1.2.1 Cross-axis motion
The maximum vibration amplitude at the check points in any axis perpendicular to the specified
axis shall not exceed 50 % of the specified amplitude up to 500 Hz or 100 % for frequencies in
excess of 500 Hz. The measurements need only cover the specified frequency range. In
special cases, e.g. small specimens, the amplitude of the permissible cross axis motion may
be limited to 25 %, if required by the relevant specification.
In some cases, for example for large size or high mass specimens or at some frequencies, it
may be difficult to achieve the figures quoted above. In such cases, the relevant specification
shall state which of the following requirements apply:
a) any cross-axis motion in excess of that stated above shall be noted and stated in the test
report; or
b) cross-axis motion which is known to offer no hazard to the specimen need not be
monitored.
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60068-2-6 © IEC:2007 – 11 –
4.1.2.2 Rotational motion
In the case of large size or high mass specimens, the occurrence of spurious rotational motion
of the vibration table may be important. If so, the relevant specification shall prescribe a
tolerable level. The achieved level shall be stated in the test report (see also A.2.4).
4.1.3 Signal tolerance
Acceleration signal tolerance measurements shall be performed if stated in the relevant
specification. They shall be carried out at the reference point and shall cover the frequencies
...
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