SIST EN 60068-2-80:2005

Environmental testing -- Part 2-80: Tests - Test Fi: Vibration - Mixed mode

Intended for general application for testing specimens when simulation is required of vibration excitation of a complex and mixed nature. The purpose of the test is to demonstrate the adequacy of the specimen to resist the specified mixed mode excitation without unacceptable degradation of its functional and/or structural performance. It is particularly useful for tailoring mixed mode environments where measured data are available for the real life environment. The test also helps reveal the accumulated effects of stress induced by random vibration, mixed with sine and/or random, and the resulting mechanical weakness and degradation in specified performances, and to use this information, in conjunction with the relevant specification, to assess the acceptability of specimens. In some cases, this standard may also be used to demonstrate the mechanical robustness of specimens. This standard is applicable to specimens which may be subjected to vibration of a random and/or a combination of random and deterministic nature resulting from transportation or real life environments, for example in aircraft, space vehicles and for items in their transportation container when the latter may be considered as part of the specimen itself. Although primarily intended for electrotechnical specimens, this standard is not restricted to such specimens and may be used in other fields where desired.

Umgebungseinflüsse -- Teil 2-80: Prüfverfahren - Prüfung Fi: Mixed-Mode Vibrationsprüfung

Essais d'environnement -- Partie 2-80: Essais - Essai Fi: Vibration - Mode mixte

Destinée à une application générale aux essais des spécimens lorsqu'une simulation d'excitation de vibrations complexes et mixtes est nécessaire. L'objectif de l'essai est de prouver l'adéquation du spécimen à résister aux excitations spécifiées en mode mixte sans provoquer de dégradation inacceptable de ses performances fonctionnelles et/ou structurelles. Cet essai est particulièrement utile pour adapter des environnements en mode mixte à l'environnement réel lorsque les données mesurées sont disponibles. L'essai permet également de révéler les effets accumulés des contraintes induites par les vibrations aléatoires, combinées sinus et/ou bruit, ainsi que la faiblesse et la dégradation mécaniques qui en résultent au niveau de la performance spécifiée, et d'utiliser ces informations associées aux spécifications particulières pour évaluer l'acceptabilité des spécimens. Dans certains cas, la présente norme peut également servir à prouver la robustesse mécanique des spécimens. La présente norme s'applique à des spécimens qui peuvent être soumis à des vibrations aléatoires et/ou à une combinaison de vibrations aléatoires et déterministes dues à l'environnement de transport ou à l'environnement réel, par exemple dans les avions ou les véhicules spatiaux ou dans les éléments du conteneur de transport lorsque celui-ci est considéré comme partie intégrante du spécimen. Bien qu'elle soit principalement destinée aux spécimens électrotechniques, la présente norme ne se limite pas à ces derniers et peut être utilisée dans d'autres domaines le cas échéant.

Okoljski preskusi – 2-80. del: Preskusi – Preskus Fi: vibracije – mešani način (IEC 60068-2-80:2005)

General Information

• Status: Published
• Publication Date: 30-Nov-2005
• ICS: 19.040 - Environmental testing
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2005
• Due Date: 01-Dec-2005
• Completion Date: 01-Dec-2005
• Ref Project: EN 60068-2-80:2005 - Environmental testing - Part 2-80: Tests - Test Fi: Vibration - Mixed mode

Standards Content (Sample)

SLOVENSKI SIST EN 60068-2-80:2005

STANDARD
december 2005
Okoljski preskusi – 2-80. del: Preskusi – Preskus Fi: vibracije – mešani način
(IEC 60068-2-80:2005)
Environmental testing – Part 2-80: Tests – Test Fi: Vibration – Mixed mode (IEC
60068-2-80:2005)
ICS 19.040 Referenčna številka
SIST EN 60068-2-80:2005(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

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EUROPEAN STANDARD EN 60068-2-80
NORME EUROPÉENNE
EUROPÄISCHE NORM July 2005

ICS 19.040; 29.020


English version


Environmental testing
Part 2-80: Tests –
Test Fi: Vibration –
Mixed mode
(IEC 60068-2-80:2005)


Essais d'environnement Umgebungseinflüsse
Partie 2-80: Essais – Teil 2-80: Prüfverfahren –
Essai Fi: Vibration - Mode mixte Prüfung Fi: Mixed-Mode Vibrationsprüfung
(CEI 60068-2-80:2005) (IEC 60068-2-80:2005)



This European Standard was approved by CENELEC on 2005-06-01. 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, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,
Switzerland and 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


© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60068-2-80:2005 E

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EN 60068-2-80:2005 - 2 -
Foreword
The text of document 104/363/FDIS, future edition 1 of IEC 60068-2-80, 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 60068-2-80 on 2005-06-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2006-03-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-06-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60068-2-80:2005 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:
ISO/IEC 17025 NOTE Harmonized as EN ISO/IEC 17025:2000 (not modified).
__________

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- 3 - EN 60068-2-80:2005
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 Where an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
IEC 60050-300 2001 International Electrotechnical Vocabulary - -
- Electrical and electronic measurements
and measuring instruments
Part 311: General terms relating to
measurements –
Part 312: General terms relating to
electrical measurements –
Part 313: Types of electrical measuring
instruments –
Part 314: Specific terms according to the
type of instrument

1)
IEC 60068-1 1988 Environmental testing EN 60068-1 1994
Part 1: General and guidance

IEC 60068-2-6 1995 Part 2: Tests - Test Fc: Vibration EN 60068-2-6 1995
+ corr. March 1995 (sinusoidal)

2)
IEC 60068-2-47 1999 Part 2-47: Test methods - Mounting of EN 60068-2-47 1999
components, equipment and other articles
for vibration, impact and similar dynamic
tests

IEC 60068-2-64 1993 Part 2: Test methods - Test Fh: Vibration, EN 60068-2-64 1994
+ corr. October 1993 broad-band random (digital control) and
guidance

IEC 60068-3-8 2003 Part 3-8: Supporting documentation and EN 60068-3-8 2003
guidance - Selecting amongst vibration
tests

IEC 60068-5-2 1990 Part 5: Guide to drafting of test methods - EN 60068-5-2 1999
Terms and definitions

ISO 2041 1990 Vibration and shock - Vocabulary - -



1)
EN 60068-1 includes corrigendum 1988 + A1:1992 to IEC 60068-1.
2)
EN 60068-2-47:1999 is superseded by EN 60068-2-47:2005, which is based on IEC 60068-2-47:2005.

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NORME CEI
INTERNATIONALE
IEC



60068-2-80
INTERNATIONAL


Première édition
STANDARD

First edition

2005-05


BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Essais d’environnement –
Partie 2-80:
Essais – Essai Fi: Vibration – Mode mixte

Environmental testing –
Part 2-80:
Tests – Test Fi: Vibration – Mixed mode



CODE PRIX
X
Commission Electrotechnique Internationale
PRICE CODE
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
Pour prix, voir catalogue en vigueur

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60068-2-80  IEC:2005 – 3 –
CONTENTS

FOREWORD.7
INTRODUCTION.11

1 Scope.13
2 Normative references .13
3 Terms and definitions .15
4 Requirements for testing .25
4.1 General .25
4.2 Control systems .25
4.3 Basic motion .25
4.4 Cross axis motion.25
4.5 Mounting .27
4.6 Measuring systems.27
5 Requirements for testing mixed mode.29
5.1 Vibration tolerances – Random.31
5.2 Vibration tolerances – Sine.37
5.3 Control strategy.39
5.4 Vibration response investigation.41
6 Severities .41
6.1 Broadband random vibration.43
6.2 Random narrowbands .43
6.3 Sine tones .45
7 Preconditioning .47
8 Initial measurements .47
9 Testing .47
9.1 General .47
9.2 Initial vibration response investigation .49
9.3 Low-level excitation for equalization prior to testing.51
9.4 Mixed mode testing .51
9.5 Final vibration response investigation.53
10 Intermediate measurements .53
11 Recovery.53
12 Final measurements .53
13 Information to be given in the relevant specification .53
14 Information to be given in the test report .55

Annex A (informative) Mixed mode general information.59
Annex B (informative) Guidance.71


Bibliography.83

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60068-2-80  IEC:2005 – 5 –

Figure 1 – Boundaries for acceleration spectral density (see also 5.1.1) .29
Figure 2 – Stochastical excitation, representation of signal clipping and Gaussian
(normal) probability.31
Figure 3 – Statistical accuracy of acceleration spectral density versus degrees of
freedom for different confidence levels .33
Figure 4 – Distribution (probability density) of sine, sine-on-random and random signals .35
Figure 5 – Recommended sinusoidal sweep rate as a function of power ratio for sine
on random depending on E .47
sor
Figure A.1 – Sine at 160 Hz .63
Figure A.2 – Sine at 380 Hz .65
Figure A.3 – Auto correlation – Sine at 160 Hz .65

Table A.1 – Determination of sine wave with APD calculation .67
Table A.2 – Determination of sine wave with autocorrelation calculation .69

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60068-2-80 © IEC:2005 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ENVIRONMENTAL TESTING –

Part 2-80: Tests – Test Fi: Vibration – Mixed mode


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 60068-2-80 has been prepared by IEC technical committee 104:
Environmental conditions, classification and methods of test.
The text of this standard is based on the following documents:
FDIS Report on voting
104/363/FDIS 104/368/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.
It has the status of a basic safety publication in accordance with IEC Guide 104.

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60068-2-80  IEC:2005 – 9 –
This standard forms Part 2-80 of IEC 60068 which consists of the following major parts, under
the general title Environmental testing:
Part 1: General and guidance
Part 2: Tests
Part 3: Supporting documentation and guidance
Part 4: Information for specification writers
Part 5: Guide to drafting of test methods
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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60068-2-80  IEC:2005 – 11 –
INTRODUCTION
This method for mixed mode vibration testing requires the digital control of broadband random
vibrations and techniques associated with the combination of sinusoidal vibration and/or
specified narrowband random with a broadband random background.
This standard is intended for general application to components, equipment and other
products, hereinafter referred to as ”specimens”, when simulation is required of broadband
responses of a complex nature for the specimens.
The test method is based primarily on the use of an electrodynamic or a servo-hydraulic
vibration generator with an associated computer based control system used as a vibration
testing system.
It is emphasized that mixed mode testing always demands a certain degree of engineering
judgement and both supplier and purchaser should be fully aware of this fact. The writer
of the relevant specification is expected to select the testing procedure and the values of
severity appropriate to the specimen and its use.

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60068-2-80  IEC:2005 – 13 –
ENVIRONMENTAL TESTING –

Part 2-80: Tests – Test Fi: Vibration – Mixed mode



1 Scope
This part of IEC 60068 is intended for general application for testing specimens when
simulation is required of vibration excitation of a complex and mixed nature.
The purpose of the test is to demonstrate the adequacy of the specimen to resist the specified
mixed mode excitation without unacceptable degradation of its functional and/or structural
performance. It is particularly useful for tailoring mixed mode environments where measured
data are available for the real life environment.
The test also helps reveal the accumulated effects of stress induced by random vibration,
mixed with sine and/or random, and the resulting mechanical weakness and degradation in
specified performances, and to use this information, in conjunction with the relevant
specification, to assess the acceptability of specimens. In some cases, this standard may also
be used to demonstrate the mechanical robustness of specimens.
This standard is applicable to specimens which may be subjected to vibration of a random
and/or a combination of random and deterministic nature resulting from transportation or real
life environments, for example in aircraft, space vehicles and for items in their transportation
container when the latter may be considered as part of the specimen itself.
Although primarily intended for electrotechnical specimens, this standard is not restricted to
such specimens and may be used in other fields where desired.
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 60050(300):2001, International Electrotechnical Vocabulary (IEV) – Electrical and
electronic measurements and measuring instruments –
Part 311: General terms relating to measurements
Part 312: General terms relating to electrical measurements
Part 313: Types of electrical measuring instruments
Part 314: Specific terms according to the type of instrument
IEC 60068-1:1988, Environmental testing – Part 1: General and guidance
IEC 60068-2-6:1995, Environmental testing – Part 2-6: Tests -Test Fc: Vibration (sinusoidal)
IEC 60068-2-47:1999, Environmental testing – Part 2-47: Test methods – Mounting of
components, equipment and other articles for vibration, impact and similar dynamic tests

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60068-2-80  IEC:2005 – 15 –
IEC 60068-2-64:1993, Environmental testing – Part 2-64: Test methods – Test Fh: Vibration,
broadband random (digital control) and guidance
IEC 60068-3-8:2003, Environmental testing – Part 3-8: Supporting documentation and
guidance – Selecting amongst vibration tests
IEC 60068-5-2:1990, Environmental testing – Part 5-2: Guide to drafting of test methods –
Terms and definitions
ISO 2041:1990, Vibration and shock – Vocabulary
3 Terms and definitions
For the purposes of this document, the following terms and definitions are generally defined in
ISO 2041, IEC 60050(300), IEC 60068-1, IEC 60068-2-6, IEC 60068-2-64 and IEC 60068-5-2.
Where, for the convenience of the reader, a definition from one of those sources is included
here, the derivation is indicated and departures from the definitions in those sources are also
indicated.
The additional terms and definitions that follow are also applicable.
3.1
cross axis motion
motion not in the direction of the external stimulus, generally specified in the two orthogonal
axes
3.2
actual motion
motion represented by the wideband signal returned from the reference point transducer
3.3
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 If a part of the real mounting structure is used as the fixture, the fixing points are taken as those of the
mounting structure and not of the specimen.
3.4
control point
3.4.1
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
3.4.2
multipoint control
control method using the signals from each of the transducers at the check points. The
signals are either continuously averaged arithmetically or processed by using comparison
techniques, depending upon the relevant specification, see also 3.9
3.5
g
n
standard acceleration due to the earth's gravity, which itself varies with altitude and geo-
graphical latitude
2
NOTE For the purposes of this standard, the value of g is rounded up to the nearest whole number, i.e. 10 m/s .
n

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60068-2-80  IEC:2005 – 17 –
3.6
measuring points
specific points at which data are gathered for conducting the test. These points are of three
types, as defined below
3.6.1
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. 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 by 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 a number of fixing points, a single check point (that is 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 procedure is only valid when the lowest resonance frequency of the loaded fixture is well
above the upper frequency of the test.
3.6.2
reference point
point, chosen from the check points, signal of which is used to control the test, such that the
requirements of this standard are satisfied
3.6.3
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
3.6.4
response points
specific points on the specimen from which data is gathered for the purpose of the vibration
response investigation
NOTE These points are not check or reference points
3.7
preferred testing axes
three orthogonal axes that correspond to the most vulnerable axes of the specimen
3.8
sampling frequency
number of discrete magnitude values taken per second to record or represent a time-history in
a digital form
3.9
multipoint control strategies
method for calculating the reference control signal when using multipoint control. The
following frequency domain control strategies are available, see also 3.4.2
3.9.1
averaging
process of determining the control value as the arithmetic average of the signal value, see
also 3.31, of each frequency at more than one check point

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60068-2-80  IEC:2005 – 19 –
3.9.2
extremal
process of determining the control value as the maximum or minimum of the signal value, see
also 3.31, of each frequency from each check point
3.10
MAX/SUM
random-on-random severities in order to define the ASD (see 3.14) value of the narrow bands
NOTE MAX means the maximum of either the background or narrow band ASD values, SUM means adding the
two ASD values.
3.11
crest factor
ratio of the peak value to the r.m.s. value of the complex mixed-mode waveform
[ISO 2041]
3.12
super positional strategy
strategy which defines the method for calculating the reference acceleration spectral density
at each frequency line from the sine tones and the random ASD
3.13
–3 dB bandwidth
B
frequency bandwidth between two points in a frequency response function which is 0,708 of
the maximum response when associated with a single resonance peak
3.14
acceleration spectral density
ASD
mean-square value of that part of an acceleration signal passed by a narrowband filter of a
centre frequency, per unit bandwidth, to the extent that the bandwidth approaches zero and
the averaging time approaches infinity
3.15
bias error
for the random signal, systematic error in the estimate of the acceleration spectral density due
to the finite frequency resolution used in practice. For the sinusoidal signal, systematic error
in the estimate of the amplitude of the sinusoidal component within the mixed mode signal
due to the averaging time
3.16
control acceleration spectral density
acceleration spectral density measured at the reference point or the fictitious point
3.17
control system loop
sum of the following actions:
– digitizing the analogue mixed mode waveform of the signal derived from the reference
point;
– performing the necessary processing;
– producing an updated analogue mixed mode drive waveform to the vibration system power
amplifier (see also Clause B.1)

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60068-2-80  IEC:2005 – 21 –
3.18
drive signal clipping
limitation of the maximum value of the drive signal, expressed as a crest factor
3.19
effective frequency range (see also Figure 1)
range from the actual frequency below f to the actual frequency above f due to initial and
1 2
final slopes
3.20
error acceleration spectral density
difference between the specified acceleration spectral density and the control acceleration
spectral density
3.21
equalization
minimization of the error acceleration spectral density
3.22
final slope (see also Figure 1)
part of the specified acceleration spectral density above f
2
3.23
frequency resolution
width of the frequency intervals in the acceleration spectral density in hertz
NOTE It is equal to the reciprocal of the length of each of the samples into which the record is partitioned in order
to calculate the indicated acceleration spectral density in digital analysis. The number of frequency lines is equal to
the number of intervals in a given frequency range.
3.24
indicated acceleration spectral density
estimate of the true acceleration spectral density read from the analyser presentation
corrupted by the instrument error, the random error and the bias error
3.25
initial slope (see also Figure 1)
part of the specified acceleration spectral density below f
1
3.26
instrument error
error associated with each analogue item of the input to the control system and control
system analogue items
3.27
random error
error changing from one estimate to another of the acceleration spectral density because of
the limitation of averaging time and filter bandwidth in practice
3.28
record
collection of equally spaced data points in the time domain that are used in the calculation of
the Fast Fourier Transform

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60068-2-80  IEC:2005 – 23 –
3.29
reproducibility
the closeness of the agreement between the results of measurements of the same value of
the same quantity where the individual measurements are made
– by different methods,
– with different measuring instruments,
– by different observers,
– in different l
...