1、 m 3404583 OLOOLbO 99T m EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 61043 January 1994 UDC 621.396 : 534.84 : 534.612.08 : 620.1 : 621.317.743 Descriptors: Electroacoustics, sound equipment, instrument for sound measurement, sound intensity, microphone, microphonic probe, verification, cha
2、racteristics, field calibration, calibration, instruction manuals, marking English version Electroacoustics - Instruments for the measurement of sound intensity - Measurement with pairs of pressure sensing microphones (IEC 1043 : 1993) Electroacoustique - Instruments pour la Elektroakustik - Gerte f
3、r die Messung der mesure de lintensit acoustique - Mesure au Schallintensitt - Messungen mit Paaren von moyen dune paire de microphones de Druckmikrofonen pression (IEC 1043 : 1993) (CE1 1043 : 1993) This European Standard was approved by CENELEC on 1993-12-08. CENELEC members are bound to comply wi
4、th the CENKENELEC 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 Secretari
5、at 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 o
6、fficial versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotech
7、nical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels O 1994 Copyright reserved to CENELEC members Ref. No. EN 61043 : 1994 E Page 2 EN 61043 : 1994 Foreword The text of document
8、 29(C0)185, as prepared by IEC %chnical Committee 29: Electroacoustics, was submitted to the IEC-CENELEC parallel vote in February 1993. The reference document was approved by CENELEC as EN 61043 on 8 December 1993. The following dates were fixed: - latest date of publication of an identical nationa
9、l Standard (dop) 1994-12-01 - latest date of withdrawal of conflicting national standards (dow) 1994-12-01 For products which have complied with the relevant national standard before 1994-12-01, as shown by the manufacturer or by a certification body, this previous standard may continue to apply for
10、 production until 1999-12-01. Annexes designated normative are part of the body of the standard. Annexes designated informative are given only for information. In this standard, annexes A and ZA are normative and annexes B, C, D and E are informative. = 3404583 OLOOLbL 82b 3404583 OLOOLb2 7b2 Page 3
11、 EN 61043 : 1994 CONTENTS Page INTRODUCTION . 5 Chuse Scope . 6 Normative references 6 Definitions 7 Grades of accuracy . 9 Reference environmental conditions 10 10 Sound intensity processors: requirements 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 6.12 6.13 6.14 Frequency range . 10 Filtering .
12、10 A-weighting . 10 Indicator accuracy . 11 Provision for microphone separation . 11 Presentation of results 11 Time averaging 11 Crest factor handling . 12 Pressure-residual intensity index 12 Provision for phase compensation . 12 Provision for range setting 12 Provision for overload indication 13
13、Provision for corrections for atmospheric pressure and temperature 13 Operating environment . 13 Sound intensity probes: requirements . 13 7.1 Mechanical construction 13 7.2 Response to sound pressure . 14 7.3 Response to sound intensity . 14 7.4 Directional response characteristics . 15 7.5 Perform
14、ance in a standing wave field . 16 7.6 Pressure-residual intensity index . 16 7.7 Environmental conditions . 17 Sound intensity instruments: requirements . 17 Power supplies: requirements 17 = 3404583 OLOOLb3 bT9 Page 4 EN 61043 : 1994 Clause Page 10 11 12 13 14 15 Sound intensity probe calibrators:
15、 requirements 10.1 10.2 10.3 17 Sound pressure calibrators 17 Residual intensity testing devices 17 Sound intensity calibrators 18 Sound intensity processors: performance verification 18 Sound intensity indication 19 Time averaging 19 Crest factor handling . 20 Pressure-residual intensity index and
16、operating fange 20 12.1 Frequency response . 21 12.2 Directional response . 22 Performance in a standing wave field 22 Calibrators: performance verification 23 11.1 11.2 11 . 3 11.4 11.5 Sound intensity probes: performance verification . 21 Octave and one-third octave filters . 18 12.3 12.4 Pressure
17、-residual intensity index 22 13.1 13.2 13.3 Sound pressure calibrators 23 Residual intensity testing devices 23 Sound intensity calibrators 23 Field calibration and checks 24 Marking and instruction manuals . 25 15.1 Marking . 25 15.2 Instruction manuals 25 Annexes A Periodic verification procedures
18、 27 B Sound intensity processors employing autoranging . 29 C Sound intensity processors based on DFT analysers converting narrow bands to octave or one-third octave 30 D RC networks for generating known phase shifts . 33 E Dynamic capability index . 34 ZA (normative) Other international publication
19、s quoted in this standard with the references of the relevant European publications . 36 W 3404583 0100164 535 Page 5 EN 61043 : 1994 INTRODUCTION This International Standard specifies the requirements for sound intensity instruments, comprising sound intensity probes and processors, which detect so
20、und intensity by pairs of spatially separated pressure sensing microphones. These instruments, and others employing different detection methods, are still the subject of development. Sound intensity instruments have two main applications. The first is the investigation of the radiation characteristi
21、cs of sound sources. The second is the determination of the sound power of sources, especially in situ, where sound intensity measurement enables sound power determination to be made under acoustical conditions which render determi- nation by sound pressure measurement impossible. This International
22、 Standard applies to instruments to be used for the determination of sound power in accordance with the requirements of IS0 9614-1 and ensures well-defined performance for instruments used in other applications. Specifications and tolerances are based on current instrument technology and on typical
23、industrial requirements for dynamic capability index. Requirements for the verification of performance of probes and processors are written in terms of type tests. A scheme for periodic verification, serving as the basis of the periodic recalibrations required in many countries, is given in annex A.
24、 Probes and processors are treated separately and together; in the latter case they are called “instruments“. Page 6 EN 61043 : 1994 ELECTROACOUSTICS - INSTRUMENTS FOR THE MEASUREMENT OF SOUND INTENSITY - MEASUREMENT WITH PAIRS OF PRESSURE SENSING MICROPHONES i Scope The primary purpose of this Stan
25、dard is to ensure the accuracy of measurements of sound intensity applied to the determination of sound power in accordance with IS0 9614-1. To meet the requirements of that standard, instruments are required to analyse the sound intensity in one-third octave or octave bands, and optionally to provi
26、de A-weighted band levels. They are also required to measure sound pressure level in addition to sound intensity level to facilitate the use of the field indicators described in IS0 9614-1. This International Standard only applies to instruments which detect sound intensity by pairs of spatially sep
27、arated pressure sensing microphones. This International Standard specifies performance requirements for instruments used for the measurement of sound intensity, and their associated calibrators. The requirements are intended to reduce to a practical minimum any differences in equi- valent measuremen
28、ts made using different instruments, including instruments comprising probes and processors from different manufacturers. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the ti
29、me of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents listed below. Members of
30、 IEC and IS0 maintain registers of currently valid International Standards. IS0 9614-1: 1993, Acoustics - Determination of sound power levels of noise sources using sound intensity - Part I: Measurement at discrete points IEC 651 : 1979, Sound level meters IEC 942: 1988, Sound calibrators IEC 1260:
31、19XX, Specification for octave-band and fractional octave-band filters (under consideration). (Revision of IEC 225: 1966) m 3404583 OLOOLbb 308 Page 7 EN 61043 : 1994 3 Definitions For the purpose of this International Standard, the following definitions apply. 3.1 to obtain the sound intensity comp
32、onent in a specific direction. sound intensity probe: Transducer system from which signals may be processed 3.2 p-p probe (also known as a two microphone probe): Probe composed of two pressure sensing microphones spaced apart by a fixed and known distance, in which the sound pressure component is me
33、asured by the two microphones and the mean value is considered as the sound pressure existing at the reference point of the probe, while the sound pressure differential is used for the purpose of deriving the sound particle velocity component. NOTES 1 2 shown in figure 2. A side-by-side p-p probe ha
34、s the two microphones arranged as shown in figurel. A face-to-face p-p probe has the two microphones facing each other and separated by a spacer as IEC 1232193 IEC li31193 Figure 1 - A side-by-side p-p probe Figure 2 -A face-to-face p-p probe 3.3 measured. reference point of a probe: Point at which
35、the sound intensity is deemed to be NOTE - The reference point of a probe is not necessarily the physical midpoint, but occurs halfway between the effective microphone centres. 3.4 of particle velocity is sensed. probe axis: Axis passing through the reference point and along which a component 3.5 re
36、ference direction: Direction of incidence of plane progressive waves on the probe, parallel to the probe axis, for which the sound intensity response of the probe is specified. 3404583 OLOOLb7 2L4 Page 8 EN 61043 : 1994 3.6 phase difference between probe channels for a p-p probe: Difference in phase
37、 response between the channels in a p-p probe, including microphones, preamplifiers and cables, if they are an integral part of the probe, when subjected to the same input. It is a function of frequency. 3.7 nominal separation of microphones in a p-p probe: Fixed value of separation used for the pur
38、pose of computing sound intensity directly in an instrument. It is the mean value of the effective separation of the microphones in a specified frequency range. 3.8 sound intensity processor: Device whose function is the determination of sound intensity in conjunction with a specified probe. The pro
39、cessor presents results in one octave or one-third octave bands, in terms of sound intensity and sound pressure, or sound intensity level and sound pressure level. 3.9 sound intensity processor. sound intensity instrument: Comprises a sound intensity probe and a compatible 3.1 O resldual intensity:
40、False intensity produced by phase differences between measurement channels, which occurs when the processor is subjected to identical elec- trical inputs to the two channels, or when the transducers in the probe connected to the processor are subjected to identical sound pressure inputs. 3.1 1 press
41、ure-residual Intensity Index: Difference between the indicated sound pressure levels and the indicated residual intensity levels, calculated with air density of 1,2048 kg/m3, in one octave or one-third octave bands, when the processor is subjected to identical electrical pink noise inputs to the two
42、 channels, or when the transducers connected to the inputs are subjected to identical pink noise sound pressure inputs. This index applies only where it is essentially independent of indicated sound pressure levei. 3.1 2 dynamic capability index: Difference between pressure-residual intensity index
43、found in an instrument and K factor, described as bias error factor, in IS0 9614. It signi- fies the maximum difference between sound pressure level and sound intensity level within which measurements according to IS0 9614 can be made for different grades of measurement accu racy. 3.13 operating ran
44、ge: Range of sound pressure levels, in decibels, between the highest and lowest levels of pink noise indicated by a processor or instrument, within which the pressure-residual intensity index meets the requirements of this standard. 3.14 electrostatic actuator: Device used for electrical measurement
45、s of the frequency response of condenser microphones. It is a metallic grid which is held close and parallel to the microphone diaphragm. An alternating test voltage, normally superimposed on a high static voltage, is applied between the actuator and the diaphragm. The resulting electro- static forc
46、es mimic the effect of a sound pressure on the microphone. 3.15 real time operation: Mode of operation of a processor such that all pertinent data appearing at inputs within the total averaging time are used in computing sound pressure and sound intensity. Page 9 EN 61043: 1994 NOTE - Depending upon
47、 particular characteristics of the processor, even in real time operation some pertinent data can be effectively lost or not fully taken into account, as described in annex C. 3.1 6 phase difference compensation: Function provided in some processors which, by applying corrections for phase differenc
48、e, offers an increase in the pressure-residual inten- sity index found during the process of calibration. NOTE - Application of this function does not reduce the component of residual intensity caused by elec- trical noise. 3.1 7 autoranging : Function provided in some processors which automatically
49、 selects the optimum range for accuracy, linearity and pressure-residual intensity index. NOTE - The use of an autoranging function is described in annex B. 3.1 8 sound pressure calibrator: Calibrator suitable for the pressure calibration of microphones or sound pressure measuring/analysing channels in a sound intensity instru- ment. 3.19 residual intensity testing device: Device which, by application of identical sound pressure simultaneously to the microphones of a p-p probe, allows direct computation of pressure-residual intensity index in a frequency band and at one or m
