SIST EN IEC 60565-2:2020

Underwater acoustics - Hydrophones - Calibration of hydrophones - Part 2: Procedures for low frequency pressure calibration (IEC 60565-2:2019)

This Standard specifies the methods for low frequency pressure calibration of hydrophones at frequencies from 0,01 Hz to several kilohertz depending on calibration method.

Wasserschall - Hydrophone - Kalibrierung von Hydrophonen - Teil 2: Verfahren für niederfrequente Druckkalibrierung (IEC 60565-2:2019)

Acoustique sous-marine - Hydrophones - Étalonnage des hydrophones - Partie 2: Procédures pour l’étalonnage à basse pression de fréquence (IEC 60565-2:2019)

L’IEC 60565-2:2019 spécifie les méthodes d’étalonnage à basse pression de fréquence des hydrophones à des fréquences comprises entre 0,01 Hz et plusieurs kilohertz selon la méthode d’étalonnage.
L’IEC 60565-2:2019, avec l’IEC 60565-1, remplace la deuxième édition de l’IEC 60565 parue en 2006. Cette édition constitue une révision technique.
L’IEC 60565-2:2019 inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
1) L’IEC 60565 a été divisée en deux parties:
• Partie 1: Procédures pour l’étalonnage en champ libre;
• Partie 2: Procédures pour l’étalonnage à basse pression de fréquence (le présent document).
2) Une méthode d’étalonnage relatif a été ajoutée à l’Article 8: Étalonnage par compensation piézoélectrique.
3) Une méthode d’étalonnage relatif a été ajoutée à l’Article 11: Etalonnage par colonne vibrante.
4) L’Article 12: Etalonnage par transducteur de pression statique a été ajouté.
5) L’Annexe A: Circuit équivalent du système d’excitation pour l’étalonnage avec une colonne vibrante, a été supprimée.
6) Les paragraphes 9.6, 9.7 et 9.8 ont été déplacés pour constituer une nouvelle Annexe A: Méthodes d’étalonnage par coupleur acoustique évolué.

Podvodna akustika - Hidrofoni - Kalibracija hidrofonov - 2. del: Postopki kalibracije z nizkimi frekvencami (IEC 60565-2:2019)

Ta standard določa metode za kalibracijo hidrofonov z nizkimi frekvencami pri frekvencah od 0,01 Hz do več kHz, odvisno od metode kalibracije.

General Information

• Status: Published
• Publication Date: 27-Nov-2019
• ICS: 17.140.50 - Electroacoustics
• Technical Committee: I11 - Imaginarni 11
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-Nov-2019
• Due Date: 25-Jan-2020
• Completion Date: 28-Nov-2019
• Ref Project: EN IEC 60565-2:2019 - Underwater acoustics - Hydrophones - Calibration of hydrophones - Part 2: Procedures for low frequency pressure calibration

Relations

• Revised: SIST EN 60565:2008 - Underwater acoustics - Hydrophones - Calibration in the frequency range 0,01 Hz to 1 MHz
• Effective Date: 04-Jun-2020
• Revised: SIST EN 60565:2008 - Underwater acoustics - Hydrophones - Calibration in the frequency range 0,01 Hz to 1 MHz
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 60565-2:2020
01-januar-2020
Podvodna akustika - Hidrofoni - Kalibracija hidrofonov - 2. del: Postopki kalibracije
z nizkimi frekvencami (IEC 60565-2:2019)
Underwater acoustics - Hydrophones - Calibration of hydrophones - Part 2: Procedures
for low frequency pressure calibration (IEC 60565-2:2019)
Wasserschall - Hydrophone - Kalibrierung von Hydrophonen - Teil 2: Verfahren für
niederfrequente Druckkalibrierung (IEC 60565-2:2019)
Acoustique sous-marine - Hydrophones - Étalonnage des hydrophones - Partie 2:
Procédures pour l’étalonnage à basse pression de fréquence (IEC 60565-2:2019)
Ta slovenski standard je istoveten z: EN IEC 60565-2:2019
ICS:
17.140.50 Elektroakustika Electroacoustics
SIST EN IEC 60565-2:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 60565-2:2020

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SIST EN IEC 60565-2:2020


EUROPEAN STANDARD EN IEC 60565-2

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2019
ICS 17.140.50

English Version
Underwater acoustics - Hydrophones - Calibration of
hydrophones - Part 2: Procedures for low frequency pressure
calibration
(IEC 60565-2:2019)
Acoustique sous-marine - Hydrophones - Étalonnage des Wasserschall - Hydrophone - Kalibrierung von
hydrophones - Partie 2: Procédures pour l'étalonnage à Hydrophonen - Teil 2: Verfahren für niederfrequente
basse pression de fréquence Druckkalibrierung
(IEC 60565-2:2019) (IEC 60565-2:2019)
This European Standard was approved by CENELEC on 2019-10-24. 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 CEN-CENELEC
Management Centre 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 CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN IEC 60565-2:2019 E

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SIST EN IEC 60565-2:2020
EN IEC 60565-2:2019 (E)
European foreword
The text of document 87/720/FDIS, future edition 1 of IEC 60565-2, prepared by IEC/TC 87
"Ultrasonics" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
EN IEC 60565-2:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-07-24
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-10-24
document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60565-2:2019 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 60565:2006 NOTE Harmonized as EN 60565:2007 (not modified)


2

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SIST EN IEC 60565-2:2020
EN IEC 60565-2:2019 (E)
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-801 -  International Electrotechnical Vocabulary - - -
Chapter 801: Acoustics and
electroacoustics
IEC 60500 2017 Underwater acoustics - Hydrophones - EN 60500 2017
Properties of hydrophones in the frequency
range 1 Hz to 500 kHz

3

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SIST EN IEC 60565-2:2020



IEC 60565-2

®


Edition 1.0 2019-09




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Underwater acoustics – Hydrophones – Calibration of hydrophones –

Part 2: Procedures for low frequency pressure calibration




Acoustique sous-marine – Hydrophones – Étalonnage des hydrophones –

Partie 2: Procédures pour l’étalonnage à basse pression de fréquence
















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 17.140.50 ISBN 978-2-8322-7346-3




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN IEC 60565-2:2020
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CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Symbols . 12
5 Procedures for calibration . 13
5.1 Principles . 13
5.2 Field limitations . 14
5.3 Schematic survey of procedures . 14
5.4 Reporting of results . 14
5.5 Recalibration periods . 15
5.6 Temperature and pressure considerations for calibration . 15
5.7 Preparation of transducers . 15
6 Electrical measurements. 15
6.1 Signal type . 15
6.2 Earthing . 15
6.3 Measurement of hydrophone output voltage . 15
6.3.1 General . 15
6.3.2 Electrical loading by measuring instrument . 15
6.3.3 Electrical loading by extension cable . 16
6.3.4 Cross-talk and acoustic interference . 16
6.3.5 Integral pre-amplifier . 16
6.4 Measurement of projector current . 16
7 Calibration by hydrostatic excitation . 16
7.1 General . 16
7.2 Principle . 16
7.2.1 Determination of the alternating pressure . 16
7.2.2 Determination of the correction factor . 18
7.2.3 Determination of the equivalent height . 18
7.2.4 Calculation of the pressure sensitivity of hydrophone . 20
7.3 Design of vibration system . 20
7.4 Alternative method for hydrostatic excitation . 20
7.5 Uncertainty . 21
8 Calibration by piezoelectric compensation . 21
8.1 General . 21
8.2 Principle . 21
8.2.1 Determination of the sound pressure . 21
8.2.2 Determination of the characteristic constant . 22
8.2.3 Calculation of the pressure sensitivity of hydrophone . 23
8.3 Design of the calibration chamber . 23
8.3.1 General . 23
8.3.2 Low frequency chamber . 23
8.3.3 High frequency chamber . 23
8.4 Practical limitations of the piezoelectric compensation method . 24
8.5 Relative calibration method . 24

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8.6 Uncertainty . 25
9 Calibration by acoustic coupler reciprocity . 25
9.1 General . 25
9.2 Principle . 25
9.2.1 Theory of acoustic coupler reciprocity . 25
9.2.2 Procedures for the reciprocity calibration . 26
9.2.3 Calculation of transfer impedance . 27
9.2.4 Determination of acoustic compliance . 27
9.3 Limitation of acoustic coupler reciprocity . 27
9.3.1 Frequency limit . 27
9.3.2 Hydrophone limit. 28
9.4 Measurement . 28
9.4.1 General . 28
9.4.2 Evidence of interference effects . 28
9.4.3 Reciprocity verification . 28
9.4.4 Linearity verification . 29
9.5 Uncertainty . 29
10 Calibration by pistonphone . 29
10.1 General . 29
10.2 Principle . 29
10.2.1 Determination of the sound pressure . 29
10.2.2 Determination of the compliance of the medium . 30
10.2.3 Calculation of the pressure sensitivity . 30
10.3 Limitations . 30
10.4 Relative calibration . 31
10.4.1 Comparison with a reference transducer . 31
10.4.2 Comparison using air–water pistonphone . 31
10.5 Uncertainty . 32
11 Calibration by vibrating column . 32
11.1 General . 32
11.2 Principle . 32
11.2.1 General . 32
11.2.2 Expression for the pressure . 33
11.2.3 Determination of the sensitivity . 34
11.3 Conditions of measurement . 35
11.3.1 Mechanical . 35
11.3.2 Acoustical . 36
11.4 Relative calibration method . 36
11.5 Uncertainty . 37
12 Calibration by static pressure transducer . 37
12.1 General . 37
12.2 Principle . 38
12.2.1 Theory of static pressure calibration . 38
12.2.2 Determination of the sensitivity of static pressure transducer . 38
12.2.3 Calculation of the pressure sensitivity . 39
12.3 Limitations . 39
12.4 Uncertainty . 39
Annex A (informative) Advanced acoustic coupler calibration methods . 40

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A.1 General . 40
A.2 Acoustic-coupler calibration using a reference coupler with two reciprocal
transducers and an auxiliary coupler with the same two transducers and a
hydrophone to be calibrated . 41
A.2.1 General . 41
A.2.2 Theory . 42
A.3 Acoustic-coupler calibration using a reference coupler with two reciprocal
transducers and an auxiliary coupler with the same two transducers, a
hydrophone to be calibrated, and a sound source . 43
A.3.1 General . 43
A.3.2 Theory . 44
A.4 Acoustic-coupler calibration using a coupler, a reciprocal transducer, a
projector, a hydrophone to be calibrated, and a subsidiary body of known
compliance . 45
A.4.1 General . 45
A.4.2 Theory . 45
Annex B (informative) Assessment of uncertainty in the low frequency pressure

calibration of hydrophone . 48
B.1 General . 48
B.2 Type A evaluation of uncertainty . 48
B.3 Type B evaluation of uncertainty . 48
B.4 Reported uncertainty . 48
B.5 Common sources of uncertainty . 49
Bibliography . 51

Figure 1 – Diagram of calibration by hydrostatic excitation . 17
Figure 2 – Schematic drawing of calibration by piezoelectric compensation . 22
Figure 3 – Diagram of the chamber for high frequency . 24
Figure 4 – Reciprocity coupler with three transducers: a projector P, a reciprocal

transducer T, and a hydrophone H to be calibrated . 26
Figure 5 – Comparison calibration using pistonphone with calibrated hydrophone . 32
Figure 6 – Diagram of calibration by vibrating column . 33
Figure 7 – Diagram of calibration by vibrating column using comparison . 37
Figure 8 –Diagram of comparison calibration using static pressure transducer . 38
Figure A.1 – Reference coupler with two transducers: a projector P and a reciprocal
transducer T . 42
Figure A.2 – Auxiliary coupler with three transducers: a projector P, a reciprocal
transducer T and a hydrophone H to be calibrated . 42
Figure A.3 – Auxiliary coupler with four transducers: a projector P, a reciprocal

transducer T, a sound source S and a hydrophone H to be calibrated . 44
Figure A.4 – Schematic drawing of the measuring system . 46

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SIST EN IEC 60565-2:2020
IEC 60565-2:2019 © IEC 2019 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

UNDERWATER ACOUSTICS – HYDROPHONES –
CALIBRATION OF HYDROPHONES –

Part 2: Procedures for low frequency pressure calibration

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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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 60565-2 has been prepared by IEC technical committee 87:
Ultrasonics.
This first edition of IEC 60565-2, together with IEC 60565-1, replaces the second edition of
IEC 60565 published in 2006. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition.
1) IEC 60565 has been divided into two parts:
• Part 1: Procedures for free-field calibration;
• Part 2: Procedures for low frequency pressure calibration (this document).
2) A relative calibration method has been added to Clause 8: Calibration by piezoelectric
compensation.

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3) A relative calibration method has been added to Clause 11: Calibration by vibrating
column.
4) Clause 12: Calibration by static pressure transducer, has been added.
5) Annex A: Equivalent circuit of the excitation system for calibration with a vibrating
column, has been deleted.
6) Subclauses 9.6, 9.7 and 9.8 have been moved to form a new Annex A: Advanced acoustic
coupler calibration methods.
The text of this International Standard is based on the following documents:
FDIS Report on voting
87/720/FDIS 87/723/RVD

Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
NOTE Words in bold in the text are terms defined in Clause 3.
A list of all parts in the IEC 60565 series, published under the general title Underwater
acoustics – Hydrophones – Calibration of hydrophones, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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SIST EN IEC 60565-2:2020
IEC 60565-2:2019 © IEC 2019 – 7 –
INTRODUCTION
The purpose of this document is to establish the procedures for low frequency pressure
calibrations of hydrophones in the frequency range from 0,01 Hz to several kilohertz.
To ensure the correctness of the calibrations, the hydrophones to be calibrated are "rigid"
hydrophones with small size compared to the acoustic wavelength, and are not sensitive to
vibration when calibrated.
Principles, procedures, and uncertainties of physical calibrations such as hydrostatic
excitation, piezoelectric compensation, pistonphone, vibrating column, static pressure
transducer, etc., and reciprocity calibrations in acoustic couplers are given in this document.
Calibrations are carried out using one of these methods, depending on the different principles
to be used, and its limitations to the sound field and the frequency range.

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UNDERWATER ACOUSTICS – HYDROPHONES –
CALIBRATION OF HYDROPHONES –

Part 2: Procedures for low frequency pressure calibration



1 Scope
This part of IEC 60565 specifies the methods for low frequency pressure calibration of
hydrophones at frequencies from 0,01 Hz to several kilohertz depending on calibration
method.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60050-801, International Electrotechnical Vocabulary – Chapter 801: Acoustics and
...