GB/T 2423.49-1997 Environmental testing for electric and electronic products Part 2: Test methods Test Fe: Vibration - Sine beat frequency method
Some standard content:
GB/T2423.49--1997
This standard is formulated based on the first edition of IEC68-2-59 "Environmental Test Methods" of the International Electrotechnical Commission.
This standard is equivalent to IEC.68-2-59, first edition in 1990. Appendix A of this standard is a prompt appendix.
This standard is proposed by the Ministry of Electronics Industry of the People's Republic of China. Test Fe: Vibration
This standard is under the jurisdiction of the National Technical Committee for Environmental Technology Standardization of Electrical and Electronic Products. The drafting units of this standard are: the Fifth Research Institute of the Ministry of Electronics Industry, and the Standardization Research Institute of the Ministry of Electronics Industry. The main drafters of this standard are: Zhang Youlan, Wang Shurong, Yang Hanxiang, Zhou Xincai, and Chen Jianer. 486
Sine Beat Frequency Method》1990
GB/T2423.49
9—1997
IEC Foreword
1) The formal resolutions or agreements of the International Electrotechnical Commission (IEC) on technical issues are formulated by technical committees represented by national committees with special concerns about the issue, and they express the international consensus on the issue as much as possible. 2) These resolutions or agreements are used internationally in the form of recommended standards and are accepted by national committees in this sense. 3) In order to promote international unification, the International Electrotechnical Commission hopes that all member countries will adopt the contents of the International Electrotechnical Commission's recommended standards as their national standards when formulating national standards, as long as the specific conditions of the country permit. Any differences between the International Electrotechnical Commission's recommended standards and national standards should be clearly stated in the national standards as much as possible. This standard was formulated by the 50th Technical Committee (Environmental Testing) of the International Electrotechnical Commission, Subcommittee 50A (Shock, Vibration and Other Dynamic Testing).
The text of this standard is based on the following documents:Draft standard
50A(C0)175bzxz.net
More detailed full voting information can be found in the voting report specified in the table above. Voting report
50A(C0)180
National Standard of the People's Republic of China
Environmental testing for electric and electronic products
Part 2: Test methods
Test Fe: Vibration-sine-beat method
Environmental testing for electric and electronic productsPart 2:Test methods
Test Fe: Vibration-sine-beat methodGB/T2423.49--1997
idt IEC 68-2-59:1990
This standard specifies the sine-beat vibration test method for components, equipment and other electric and electronic products. Because these components, equipment and other electrical and electronic products (hereinafter referred to as samples) will be subjected to short-duration pulses and oscillatory forces caused by earthquakes, explosions or machine vibrations during use.
In this test, the sample is excited with a number of predetermined sinusoidal beat frequency vibrations at a fixed frequency (see Figure 1). These fixed test frequencies are either predetermined frequencies or dangerous frequencies identified by means of the sinusoidal vibration test (GB/T2423.10). There is an interval between independent sinusoidal beat frequencies to allow the self-response of the sample to decay. A detailed list of details that must be included in the preparation of relevant specifications is listed in Chapter 12 of this standard, and guidance is provided in the guidelines of Appendix A (indicative appendix).
Cited standards
The provisions contained in the following standards constitute the provisions of this standard by reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T2298-91 Mechanical vibration and shock terminology (neqISO2041:1990) GB2421--89 General rules for basic environmental testing procedures for electric and electronic products (eqVIEC68-1:1988) GB/T2423.10--1995 Environmental testing for electric and electronic products Part 2: Test methods Test Fc and guidance: Vibration (sinusoidal) (idtIEC 68-2-6:1982)
GB/T2423.43-1995 Environmental testing for electric and electronic products Part 2: Test methods Installation requirements and guidance for components, equipment and other products in dynamic tests such as shock (Ea), collision (Eb) vibration (Fc and Fd) and steady-state acceleration (Ga) (idtIE68-2-47:1982) 1 Purpose
Provide a standard procedure using a sine-beat frequency vibration test method to determine the ability of a sample to withstand transient vibration of a specified severity level. 2 General description
The purpose of this test is to determine the mechanical weakness of the sample and/or the degradation of the specified performance according to the specified performance, and use this information, in conjunction with the relevant specifications, to determine whether the sample is accepted. In some cases, this standard can also be used to determine the mechanical strength of the sample and study their dynamic characteristics.
GB/T 2423.49.--1997
The relevant specifications should specify that the sample must be working or just subjected to vibration conditions during the test. This standard specifies the procedures for conducting the test and the methods for making vibration measurements at given points. It also describes in detail the requirements for the vibration motion and the selection of the severity level (including frequency range, amplitude, period of sine beat frequency, number of sine beat frequency). It should be emphasized that vibration testing always involves a certain degree of engineering judgment, and both the supplier and the buyer should be fully aware of this. It is expected that the compiler of the relevant specification will select the test procedure and the value of the severity level that are appropriate to the sample and its use requirements. For the purpose of this test, the sample is usually fastened to the vibration table. For the convenience of use of this standard, the main body and appendix of this standard give the chapter numbers that the reader needs to cross-reference. In addition, the appendix gives special information on the relationship between displacement, velocity and acceleration. This standard should be used in conjunction with GB2421.
3 Definitions
The terms used in this standard have been generally defined in GB/T2298 and GB/T2423.10. For the convenience of the reader, some definitions from these texts are included here, and differences and inconsistencies with other texts are pointed out. The following additional terms and definitions also apply to this standard 3.1 Critical frequency (technically equivalent to 8.1 in GB/T2423.10) The frequency at which the sample fails and/or performance deteriorates due to vibration. Or the frequency at which mechanical resonance and/or other effects such as flutter occur.
3.2 Crossover frequency (technically equivalent to the definition in GB/T2298) The frequency at which the vibration characteristics change from one relationship to another. Note: For example, the crossover frequency can be the frequency at which the amplitude of the vibration test changes from a constant displacement value as a function of frequency to a constant acceleration value as a function of frequency.
3.3 Damping (different from the definition in GB/T2298) Damping is a general term to describe the energy loss caused by various mechanisms in a system. In practice, damping depends on many parameters, such as system structure, vibration mode, stress, applied force, speed, material, connection slip, etc. 3.3.1 Critical damping critical damping The minimum viscous damping that allows a displaced system to return to its initial position without oscillation 3.3.2 Damping ratio damping ratio
In a viscous damping system, the ratio of actual damping to critical damping. 3.4 Distortion (same as Chapter 3 of GB/T2423.10, different from GB/T2298) Distortion d
Vaot ai
×100 (expressed as a percentage)
Where: ,-—Root mean square acceleration value at the driving frequency; ato—Total root mean square acceleration value applied (including α value). 3.5 Fixing point (same as 3.1 of GB/T2423.10) The part where the sample contacts the fixture or the vibration table surface. In actual use, this is usually the place where the sample is fastened. Note: If a part of the actual installation structure is used as a fixture, the fixing point is the fixing point of the installation structure, not the fixing point of the sample. 3.6 Acceleration of gravity “gn” is the standard acceleration due to the earth’s gravity, which itself varies with altitude and latitude. Note: In this standard, the value of g is taken as an integer, 10 m/s. 3.7 Measuring point (technically the same as 3.2 in GB/T 2423.10) Special point at which data is collected for the test. These points have two main forms and are defined as follows: Note: In order to evaluate the performance of the sample, measurements can be made at many points in the sample, but these points are not considered as measuring points in this standard. ()
3.7. 1 Check point
GB/T 2423.49-1997
A point located on the fixture, vibration table or sample, which should be as close as possible to one of the fixed points and in any case be rigidly connected to the fixed point.
1 These check points are used to ensure that the test requirements are met. 2 If there are 4 or fewer fixed points, each fixed point is used as a check point. If there are more than 4 fixed points, the relevant specification should specify 4 representative fixed points for use as check points. 3 In special cases, such as for large or complex samples, if the check point is not required to be close to the fixed point, the check point should be specified in the relevant specifications. 4 When a large number of small samples are mounted on a fixture, or when a small sample has many fixed points, a single check point (i.e., reference point) can be selected to derive the control signal. The control signal is related to the fixture and has nothing to do with the fixed point of the sample. This method is only feasible when the lowest resonant frequency of the fixture after loading exceeds the upper frequency limit of the test by a large margin. 3.7.2 Reference point (technically the same as 3.2.2 in GB/T 2423.10) A point selected from the check points, whose signal is used to control the test in order to meet the requirements of this standard. 3.8 Modulating frequency modulating frequency frequency of the test frequency (see Chapter A2, Chapter A3 and Figure 1). 3.9 Hight-stress cycles response cycles that produce stress values that will cause fatigue of the sample. 3.10 pause
pause between two adjacent sine beats.
Note: The interval should be such that the response movement of the sample does not produce effective selection. Its duration can be obtained from the following mathematical formula: 1100
Where; ... duration, s;
f-test frequency, Hz;
d-critical damping of a test frequency, %.
3.11 Preferred testing axes preferred testing axes basically correspond to the three orthogonal axes of the most vulnerable axis of the sample, 3.12 Sine beat sine beat
· (2)
A continuous sine wave of a certain frequency modulated by a lower frequency sine wave. The duration of a sine beat is half a cycle of the modulation frequency (see Figure 5).
Note: The mathematical expression of the E-string beat signal is shown in A2.1. 3.13 Sweep cycle (technically equivalent to Chapter 3 of GB/T 2423.10) Sweep through the specified frequency range in each direction - times, for example 1Hz→35Hz→1Hz. 3.14 Test frequency test frequency
The frequency at which the sample is excited during the test. The test frequency is one of the following two types and is defined as follows: 3.14.1 Predetermined test frequency The frequency specified in the relevant specification.
3.14.2 Investigated test frequency The frequency obtained by the vibration response check. 3.15 Test level test level
The maximum peak value in the test waveform.
Note: This value is equal to or slightly less than the peak value of the modulation half wave. 490
4 Requirements for conditional tests
GB/T 2423.49-1997
4.1 specifies the requirements for vibration response checks. 4.2 specifies the requirements for sine beat frequency conditional tests, while 4.3 specifies the requirements for the installation of test samples.
The tolerances specified for vibration response checks and for sine beat frequency conditional tests are compared in Table 1. Table 1 Tolerance comparison
Vibration response check
Distortion
Vibration at the reference point
Vibration at the check point
Lateral movement
Test frequency
4.1 Vibration response check
25% of basic movement (see 4.1.5)
Basic movement ±15% (see 4.1.6.1)
±25% of acceleration below 500 Hz (see 4.1.6.2); above 500 Hz
Acceleration ±50% (see 4.1.6.2)
50% or 25% in special cases (see 4.1.2) Below 0.5 Hz: ±0. 05 Hz
0. 5 Hz~5 Hz: ±10%
5 Hz~100 Hz: ± 0. 5 Hz
Above 100 Hz: ±0.5% (see 4.1.7)
Sine-beat frequency condition test
Not applicable
25% (see 4.2)
a) Predetermined frequency (see 4.2.5.1):
Below 0. 5 Hz, ±0. 05 Hz
0.5 Hz~5 Hz: ±10%
1 5 Hz~100 Hz: ±0. 5 Hz
1 100 Hz Above: ±0.5%
, b) Inspection frequency (see 4.2.5.2): ±2% When the relevant specifications require, the vibration response check shall be carried out in accordance with the method in GB/T2423.10, with special consideration given to the requirements of 4.1.1 to 4.1.8 below.
4.1.1 Basic motion
The basic motion shall be a sinusoidal function of time. The relevant specifications shall specify the fixed points of the sample on the vibration table. These points shall be basically in phase and move along parallel straight lines and meet the tolerance requirements specified in 4.1.2, 4.1.3 and 4.1.5. 4.1.2 Lateral motion
The maximum vibration at the inspection point on any axis perpendicular to the specified axis shall not exceed 50% of the basic motion. In special cases, such as for small samples, if the relevant specifications require, the peak value of the lateral vibration may be limited to 25%. At certain frequencies, or for specimens of large size or mass, it may be difficult to achieve these requirements (see Section A1). In such cases, the specification shall specify one of the following: a) Transverse motion in excess of that specified above shall be recorded in the test report; b) Transverse motion shall not be monitored.
4.1.3 Rotational motion
When parasitic rotational motion of the shaker may be significant, the specification may specify tolerance requirements which shall then be written in the test report. 4.1.4 Measuring points
4.1.4.1 Reference points
The specification shall specify whether single-point or multiple-point control is to be used. When the specification specifies multiple-point control, it shall specify whether the signal at the check point is approximately the mean or the signal at selected points is controlled to the specified value. 4.1.4.2 Check points
At certain frequencies, and for specimens of large size or mass, it may be difficult to achieve the tolerances required in 4.1.6.2 (see Section A1). In such cases, the relevant specification shall specify a wider tolerance, or use an alternative assessment method, and shall state this in the test report. 4.1.5 Acceleration waveform distortion
GB/T 2423.49--1997
Measurements of acceleration waveform distortion shall be made at reference points over a frequency range up to five times the test frequency. Distortion as defined in Clause 3 shall not exceed 25% of the fundamental motion. NOTE: In some cases it may not be possible to meet these requirements. In such cases, a distortion greater than 25% may be acceptable if the test ellipse value of the fundamental frequency control signal is restored to the specified value, e.g. by using a tracking filter. For large or complex specimens, the specified distortion may not be met over certain parts of the frequency range and the use of a tracking filter is not practical. In this case, the acceleration does not need to be restored and the distortion shall be stated in the test report (see Clause A1). Whether or not a tracking filter is used, the relevant specification may require that the distortion and the frequency range affected be recorded. 4.1.6 Tolerances on vibration amplitude
The basic vibration at the check point and the reference point along the required axis shall be equal to the specified values of the following tolerances, which include instrument errors.
4.1.6.1 Reference point
Tolerance of the control signal at the reference point:
±15% (basic movement).
4.1.6.2 Checkpoints
Tolerance at each checkpoint:
Below 500 Hz: ±25% (acceleration); above 500 Hz: ±50% (acceleration). 4.1.7 Frequency range and tolerance
The frequency range shall be selected from Tables 2, 3 and 4 of 5.1.2 and shall at least include the range of the sinusoidal beat frequency condition test. The tolerances for hazardous frequencies shall be as follows:Below 0.5 Hz: ±0. 05 Hz;
0. 5 Hz~5 Hz: ±10%;
5 Hz~100 Hz: ±0. 5 Hz:
Above 100 Hz: ±0.5%.
4.1.8 Frequency sweep
The frequency sweep shall be continuous and vary exponentially with time at a rate not exceeding one octave per minute (see 3.13). NOTE: It is not strictly correct to say that the sweep is "continuous" when a digital control system is used, but the distinction has no practical significance. 4.2 Tests under Sine Beat Frequency Conditions
Tests under Sine Beat Frequency Conditions shall take into account the following: 4.2.1 Basic Motion
The basic motion shall be a sinusoidal function of the sine beat frequency in time and shall be substantially in phase with the specimen at each fixed point on the shaker and move along parallel straight lines as specified in the relevant specification and in accordance with the tolerances of 4.2.2, 4.2.3 and 4.2.4. 4.2.2 Transverse Motion
The peak maximum displacement at the check point on any axis perpendicular to the specified axis shall not exceed 25% of the peak value specified in the sine beat frequency unless otherwise specified in the relevant specification. The measurement shall cover only the specified frequency range. At certain frequencies, or for specimens of large size or mass, it may be difficult to achieve these values (see also Section A1). In such cases, the relevant specification shall specify which of the following applies: a) Transverse motion exceeding the above shall be recorded in the test report; b) Transverse motion shall not be monitored.
4.2.3 Rotational motion
When parasitic rotational motion of the shaker may be significant, the relevant specification may specify tolerance requirements and record them in the test report. 4.2.4 Vibration amplitude tolerances
The basic motion at the check points and reference points along the required axis shall be equal to the specified values within the following tolerances, which include instrument errors. 4.92
4.2.4.1 Reference points
Tolerance of control signals at reference points:
±15% (basic motion).
4.2.4.2 Check points
Tolerance at each check point:
Below 500 Hz: ±25% (acceleration); above 500 Hz: ±50% (acceleration). GB/T 2423.49-1997
It may be difficult to achieve the required tolerance at certain frequencies or for samples of large size or mass (see Chapter A1). In this case, the relevant specification shall specify a wider tolerance or use an alternative evaluation method and record it in the test report. 4.2.5 Test frequency tolerance
The test frequency tolerance has the following two cases: 4.2.5.1 Predetermined test frequency
Below 0.5 Hz: ±0.05 Hz;
0.5 Hz~5 Hz: ±10%;
5 Hz~~100 Hz: ±0.5 Hz;
Above 100 Hz: ±0.5%.
4.2.5.2 Exploration test frequency
The frequency deviation between the test frequency and the critical frequency obtained by the vibration response check shall not exceed ±2%. 4.3 Installation
The sample shall be installed in accordance with the installation requirements of GB/T2423.10, as the installation part of this standard refers to GB/T2423.43.
If the sample is usually installed on a shock absorber and the shock absorber must be removed for testing, the specified excitation level should be modified.
When installing the sample, the influence of connectors, cables, conduits, etc. should be considered. Note: The test should include the installation structure of the sample in normal use. The relevant specifications should specify the orientation and installation method of the sample during the conditional test, and are the only conditions for considering that the sample meets the requirements of this standard, unless sufficient reasons can be given to show that the installation and orientation have no effect on the test (for example, if it can be proved that the gravity effect does not affect the performance of the sample).
5 Severity level
The test severity level is determined by the combination of the following parameters: ... - test frequency range;
test quantity value;
cycles in a sine beat frequency;
number of sine beat frequencies.
The relevant specification shall specify the value of each parameter based on the information given in 5.1 to 5.4. 5.1 Test frequency
The test frequency and frequency range are obtained as follows: 5.1.1 Determination of test frequency
The test frequency to be used is the dangerous frequency determined by the vibration response check, any predetermined frequency or these two frequencies. In the event that no dangerous frequency is found during the vibration response check and the relevant specification does not specify the method for determining the test frequency, then the test shall be carried out at a frequency not greater than one-half octave within the test frequency range selected from the values given in 5.1.2. 5.1.2 Test frequency range
GB/T2423.49-1997
The relevant specification shall give the test frequency range by selecting a lower limit frequency from Table 2 and an upper limit frequency from Table 3. The recommended frequency range is shown in Table 4. Table 2
Lower frequency
Upper frequency
Table 4 Recommended test frequency range
From fi~f
1~100
10~100*
Note: There is no frequency range marked with an asterisk in the recommended frequency range of GB/T2423.10. 5.2 Test quantity
The relevant specification shall specify the peak value of the test quantity (displacement or acceleration or both) for each axis (see Chapter A3). Hz
All peak values below the crossover frequency are specified as constant displacement, and peak values above the crossover frequency are specified as constant acceleration. The recommended values for different crossover frequencies are listed in Tables 5, 6 and 7, as well as Figures 2, 3 and 4. Table 5 Recommended test quantity values at 0.8Hz crossover frequency (see Figure 2) Displacement amplitude below the crossover frequency
All the above values refer to the peak value in the sine beat frequency. Acceleration amplitude above the crossover frequency
When the acceleration is expressed in "g." as the unit, \g." is specified in this standard as 10m/s (see 3.6).49
GB/T 2423.49—1997
Table 6Recommended test values at 1.6Hz crossover frequency (see Figure 3)Displacement amplitude below the crossover frequency
All the above values refer to the peak value in the sine beat frequency. Acceleration amplitude above the crossover frequency
When the acceleration is expressed in \gn\ as the unit, \gn" is specified in this standard as 10m/s (see 3.6). Table 7Recommended test values at 8Hz crossover frequency (see Figure 4)Displacement amplitude below the crossover frequency
1All the above values refer to the peak value in the sine beat frequency. Acceleration amplitude above the crossover frequency
2·When the acceleration is expressed in "g." as the unit, this standard stipulates that \g," is 10m/s3 (see 3.6). If the crossover frequency specified in this clause is not applicable, the relevant specifications may give different crossover frequencies to combine the displacement/acceleration peak values. For special applications, more than one crossover frequency may also be specified. 5.3 Waveform of sine beat frequency test
The waveform of the sine beat frequency test is determined by the test frequency and the number of cycles in the sine beat frequency in accordance with 5.3.1 and 5.3.2 (see Figure 5). 5.3.1 Number of cycles in the sine beat frequency
The relevant specifications shall specify the number of cycles of the sine beat frequency according to the following values (see Figure 5): 3, 5, 10, 20
Note: "5\ of the above four cycle numbers is the preferred value because this value represents a comprehensive consideration between covering a wide-band signal that cannot determine the hazardous frequency and the need for a high response value (based on actual experience) (see Figure 6). 5.3.2 Modulation frequency
The modulation frequency is derived from the test frequency and the number of cycles of the sine beat frequency (see A2.2). 5.4 Number of sine beat frequencies
The relevant specifications shall specify the number of sine beat frequencies according to the following series (see Figure 1). 1, 2, 5, 10, 20, 50
5.5 Low-cycle high-stress fatigue effect
GB/T2423.49—1997
The relevant specifications may specify the number of high-stress cycles required to be greater than the specified stress value (see Chapter A4): 6 Pretreatment
The relevant specifications may require pretreatment.
7 Initial inspection
The samples shall be inspected for appearance, dimensions and function in accordance with the requirements of the relevant specifications. 8 Conditioning test
8.1 General
Unless otherwise specified in the relevant specification, the specimen shall be vibrated in each of the three preferred test axes as described in 8.2 and 8.3. The order in which the tests are conducted along these axes is not important unless otherwise specified in the relevant specification. : When specified in the relevant specification, the control of the specified test quantity value shall be supplemented by an upper limit on the maximum driving force applied to the vibration table. The method of limiting the force shall also be specified in the relevant specification. 8.2 Vibration response check
When the relevant specification specifies a response check, a response check shall be made over the test frequency range in order to study the dynamic characteristics of the specimen under vibration conditions. The vibration response check shall be made with a sine wave over the test frequency range and at the test quantity values specified in the relevant specification. The vibration response check is usually made at a logarithmic sweep rate of not more than one octave per minute. However, if the response characteristics are to be determined more accurately, the sweep rate may be slower, but undue pauses shall be avoided. During the vibration response check, the excitation peak should be selected so that the response of the sample remains below the peak value during the sine beat frequency condition test, but at a sufficiently high value to detect the critical frequency. If required by the relevant specification, the sample should be operated during the vibration response check. If the mechanical vibration characteristics cannot be evaluated because the sample is in operation, an additional vibration response check should be carried out under the condition that the sample is not in operation. At this stage, the sample should be checked to determine the critical frequency and the results of the check should be written in the test report. In some cases, the relevant specification may require an additional response check after the sine beat frequency condition test to compare the critical frequency before and after the condition test. The relevant specification should specify what measures should be taken if the frequency changes. It is most important that the two vibration response checks are carried out in the same way and at the same value. 8.3 Sine beat frequency condition test
For the sine beat frequency condition test, the relevant specification gives the test severity level according to the provisions of Chapter 5. There should be a pause between consecutive sine beat frequencies so that the response movement of the sample does not effectively superimpose. The actual control signal at the reference point, including the effect of any filter used, shall be recorded in the test report. The relevant specification shall also specify whether single-axis or dual-axis testing is required. 8.3.1 Single-axis testing
Unless otherwise specified in the relevant specification, single-axis testing is preferred and is carried out continuously along each preferred test axis. If the relevant specification does not specify, the test sequence along these axes is not important. 8.3.2 Dual-axis testing
When specified in the relevant specification, the test shall be carried out along both preferred test axes simultaneously with sinusoidal beat frequencies. The test sequence at each test frequency shall be between 0° and 180° relative phase offset. NOTE This is effectively the same as a series of single-axis tests in different angular planes. 8.3.3 Triaxial testing
Triaxial testing is not applicable to sinusoidal beat frequency testing. 9 Intermediate testing
When required by the relevant specification, the sample shall be operated during the specified number of sinusoidal beat frequency tests and its performance shall be checked. -196
10 Recovery
GB/T 2423.49--1997
When the relevant specification specifies, it is sometimes necessary to specify a period of time after the conditioning test and before the final measurement so that the sample can reach the same conditions as at the time of the initial measurement, such as temperature.
11 Final inspection
The sample should be inspected for appearance, dimensions and function in accordance with the provisions of the relevant specification. The relevant specification should specify the criteria for accepting or rejecting the sample. 12 Provisions to be made in the relevant specification
When the relevant specification includes this test, the following details should be specified whenever applicable, and special attention should be paid to the items marked with an asterisk "*" because these items are always indispensable.
a) fixed point* (see 4.1.1 and 4.2.1); b) lateral movement (see 4.1.2 and 4.2.2); c) rotational movement (see 4.1.3 and 4.2.3); d) measuring point (see 4.1.4);
e) acceleration distortion (see 4.1.5);
f) amplitude tolerance (see 4.1.6 and 4.2.4); g) mounting of the sample (see 4.3);
h) test frequency* (see 5.1.1);
i) test frequency range* (see 5.1.2); j) test quantity value* (see Chapter A3 and 5.2); k) number of periods in the sine beat frequency* (see 5.3.1 )；1) Number of sine beat frequencies* (see 5.4);
m) Number of high stress cycles* (see Clause A4 and 5.5);n) Preconditioning (see Clause 6);
0) Initial test* (see Clause 7);
p) Preferred test axis (see 8.1);
q) Driving force limitation (see 8.1);
r) Vibration response check (see 8.2);
s) Performance and function check (see 8.2);
t) Single axis or dual axis test* (see 8.3);u) Intermediate measurement (see Clause 9);
v) Recovery (see Clause 10);
w) Final test (see Clause 11).2 and 4.2.2); c) rotational motion (see 4.1.3 and 4.2.3); d) measuring point (see 4.1.4);
e) acceleration distortion (see 4.1.5);
f) amplitude tolerance (see 4.1.6 and 4.2.4); g) sample installation (see 4.3);
h) test frequency* (see 5.1.1);
i) test frequency range* (see 5.1.2); j) test quantity value* (see Chapter A3 and 5.2); k) number of periods in the sine beat frequency* (see 5.3.1); 1) number of sine beat frequencies* (see 5.4); ||t t||m) Number of high stress cycles* (see Clause A4 and 5.5); n) Preconditioning (see Clause 6);
0) Initial test* (see Clause 7);
p) Preferred test axis (see 8.1);
q) Driving force limitation (see 8.1);
r) Vibration response check (see 8.2);
s) Performance and function check (see 8.2);
t) Single-axis or dual-axis test* (see 8.3); u) Intermediate measurements (see Clause 9);
v) Recovery (see Clause 10);
w) Final test (see Clause 11).2 and 4.2.2); c) rotational motion (see 4.1.3 and 4.2.3); d) measuring point (see 4.1.4);
e) acceleration distortion (see 4.1.5);
f) amplitude tolerance (see 4.1.6 and 4.2.4); g) sample installation (see 4.3);
h) test frequency* (see 5.1.1);
i) test frequency range* (see 5.1.2); j) test quantity value* (see Chapter A3 and 5.2); k) number of periods in the sine beat frequency* (see 5.3.1); 1) number of sine beat frequencies* (see 5.4); ||t t||m) Number of high stress cycles* (see Clause A4 and 5.5); n) Preconditioning (see Clause 6);
0) Initial test* (see Clause 7);
p) Preferred test axis (see 8.1);
q) Driving force limitation (see 8.1);
r) Vibration response check (see 8.2);
s) Performance and function check (see 8.2);
t) Single-axis or dual-axis test* (see 8.3); u) Intermediate measurements (see Clause 9);
v) Recovery (see Clause 10);
w) Final test (see Clause 11).
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