SIST EN ISO 15548-1:2009
Non-destructive testing - Equipment for eddy current examination - Part 1: Instrument characteristics and verification (ISO 15548-1:2008)
Non-destructive testing - Equipment for eddy current examination - Part 1: Instrument characteristics and verification (ISO 15548-1:2008)
This part of ISO 15548 identifies the functional characteristics of a general-purpose eddy current instrument and provides methods for their measurement and verification. The evaluation of these characteristics permits a well-defined description and comparability of eddy current equipment. By careful choice of the characteristics, a consistent and effective eddy current examination system can be designed for a specific application. Where accessories are used, these are characterised using the principles of this part of ISO 15548. This part of ISO 15548 gives neither the extent of verification nor acceptance criteria for the characteristics. They are given in the application documents.
Zerstörungsfreie Prüfung - Wirbelstromprüfung - Kenngrößen von Prüfeinrichtungen und deren Verifizierung - Teil 1: Kenngrößen von Prüfgeräten und deren Verifizierung (ISO 15548-1:2008)
Diese Europäische Norm erläutert Funktionskennwerte von Wirbelstromprüfeinrichtungen für die allgemeine Anwendung und zeigt Verfahren für deren Messung und Verifizierung.
Die Bewertung dieser Kennwerte erlaubt eine verständliche Beschreibung und Vergleichbarkeit von Wirbelstromprüfeinrichtungen.
Mit einer sorgfältigen Auswahl der Kennwerte ist es möglich, ein angemessenes und effizientes Wirbelstromprüfsystem für einen besonderen Anwendungsfall aufzubauen.
Zusatzeinrichtungen sollten, sofern sie eingesetzt werden, nach den Grundsätzen der vorliegenden Norm charakterisiert werden.
Diese Europäische Norm gibt keine Annahmekriterien für die Kennwerte an. Diese werden in der Anwendungsdokumentation angegeben.
Essais non destructifs - Équipement pour examens par courants de Foucault - Partie 1: Caractéristiques et vérification des instruments (ISO 15548-1:2008)
L'ISO 15548-1:2008 identifie les caractéristiques fonctionnelles d'un appareil à courants de Foucault à usage général et fournit des méthodes pour les mesurer et les vérifier.
L'évaluation de ces caractéristiques permet de donner une description bien définie de l'appareillage à courants de Foucault et d'assurer la comparabilité entre appareillages.
Un système d'examen par courants de Foucault, cohérent et efficace, peut être conçu en procédant à un choix scrupuleux des caractéristiques pour une application spécifique.
Lorsque des accessoires sont mis en œuvre, il convient de les caractériser en appliquant les principes de l'ISO 15548-1:2008.
L'ISO 15548-1:2008 ne donne ni l'étendue de la vérification ni les critères d'acceptation des caractéristiques. Celles-ci sont définies dans les documents d'application.
Neporušitveno preskušanje - Oprema za preskušanje z vrtinčnimi tokovi - 1. del: Značilnosti aparatov in preverjanje (ISO 15548-1:2008)
Ta del ISO 15548 navaja funkcionalne značilnosti instrumentov za preskušanje z vrtinčnimi tokovi za splošno rabo in predpisuje metode za njihovo merjenje in preverjanje. Ovrednotenje teh značilnosti omogoča dobro definiran opis in primerljivost opreme za preskušanje z vrtinčnimi tokovi. S premišljeno izbiro značilnosti je možno zasnovati konsistenten in učinkovit sistem preskušanja z vrtinčnimi tokovi za določeno uporabo. Kadar se uporablja pribor, je le-ta določen z uporabo načel tega dela ISO 15548. Ta del ISO 15548 ne podaja obsega preverjanja, kot tudi ne merila sprejemljivosti za značilnosti. Ta so podana v dokumentu, ki obravnava uporabo.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 15548-1:2009
01-april-2009
1DGRPHãþD
SIST EN 13860-1:2004
1HSRUXãLWYHQRSUHVNXãDQMH2SUHPD]DSUHVNXãDQMH]YUWLQþQLPLWRNRYLGHO
=QDþLOQRVWLDSDUDWRYLQSUHYHUMDQMH ,62
Non-destructive testing - Equipment for eddy current examination - Part 1: Instrument
characteristics and verification (ISO 15548-1:2008)
Zerstörungsfreie Prüfung - Wirbelstromprüfung - Kenngrößen von Prüfeinrichtungen und
deren Verifizierung - Teil 1: Kenngrößen von Prüfgeräten und deren Verifizierung (ISO
15548-1:2008)
Essais non destructifs - Équipement pour examens par courants de Foucault - Partie 1:
Caractéristiques et vérification des instruments (ISO 15548-1:2008)
Ta slovenski standard je istoveten z: EN ISO 15548-1:2008
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
SIST EN ISO 15548-1:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 15548-1:2009
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SIST EN ISO 15548-1:2009
EUROPEAN STANDARD
EN ISO 15548-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2008
ICS 19.100 Supersedes EN 13860-1:2003
English Version
Non-destructive testing - Equipment for eddy current
examination - Part 1: Instrument characteristics and verification
(ISO 15548-1:2008)
Essais non destructifs - Appareillage pour examen par Zerstörungsfreie Prüfung - Wirbelstromprüfung -
courants de Foucault - Partie 1: Caractéristiques de Kenngrößen von Prüfeinrichtungen und deren Verifizierung
l'appareil et vérifications (ISO 15548-1:2008) - Teil 1: Kenngrößen von Prüfgeräten und deren
Verifizierung (ISO 15548-1:2008)
This European Standard was approved by CEN on 6 September 2008.
CEN 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 Management Centre or to any CEN 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 CEN member into its own language and notified to the CEN Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15548-1:2008: E
worldwide for CEN national Members.
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SIST EN ISO 15548-1:2009
EN ISO 15548-1:2008 (E)
Contents Page
Foreword.3
2
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SIST EN ISO 15548-1:2009
EN ISO 15548-1:2008 (E)
Foreword
This document (EN ISO 15548-1:2008) has been prepared by Technical Committee CEN/TC 138 “Non-
destructive testing”, the secretariat of which is held by AFNOR, in collaboration with Technical Committee
ISO/TC 135 "Non-destructive testing".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by March 2009, and conflicting national standards shall be withdrawn at
the latest by March 2009.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 13860-1:2003.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EC Directive(s).
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
3
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SIST EN ISO 15548-1:2009
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SIST EN ISO 15548-1:2009
INTERNATIONAL ISO
STANDARD 15548-1
First edition
2008-09-15
Non-destructive testing — Equipment for
eddy current examination —
Part 1:
Instrument characteristics and
verification
Essais non destructifs — Appareillage pour examen par courants de
Foucault —
Partie 1: Caractéristiques de l'appareil et vérifications
Reference number
ISO 15548-1:2008(E)
©
ISO 2008
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
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Published in Switzerland
ii © ISO 2008 – All rights reserved
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
Contents Page
Foreword. v
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Eddy current instrument characteristics .1
4.1 General characteristics .1
4.1.1 Type of instrument.1
4.1.2 Power supply.2
4.1.3 Safety .2
4.1.4 Technology.2
4.1.5 Physical presentation.2
4.1.6 Environmental effects .2
4.2 Electrical characteristics .2
4.2.1 General.2
4.2.2 Functional block diagram .3
4.2.3 Generator unit .3
4.2.4 Input stage characteristics .4
4.2.5 Balance .4
4.2.6 High-frequency signal processing.4
4.2.7 Demodulated signal processing .5
4.2.8 Output and signal display.6
4.2.9 Digitization.7
5 Verification .7
5.1 General.7
5.2 Levels of verification .8
5.3 Verification procedure.9
5.4 Corrective actions.9
6 Measurement of the electrical characteristics of the instrument .9
6.1 Measuring requirements .9
6.2 Generator unit .9
6.2.1 Excitation frequency .9
6.2.2 Harmonic distortion.10
6.2.3 Source impedance.11
6.2.4 Maximum output voltage, V .12
Omax
6.2.5 Maximum output current, I .12
Omax
6.3 Input stage characteristics .13
6.3.1 Maximum allowable input voltage.13
6.3.2 Input impedance .14
6.4 Signal processing.14
6.4.1 General.14
6.4.2 Measurement conditions .15
6.4.3 Balance .15
6.4.4 Harmonic attenuation.16
6.4.5 Frequency response of the signal processing stage.16
6.4.6 Bandwidth.18
6.4.7 Phase linearity.18
6.4.8 Orthogonality of components .19
6.4.9 Gain-setting accuracy .20
6.4.10 Phase-setting accuracy.20
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ISO 15548-1:2008(E)
6.4.11 Cross-talk. 21
6.4.12 Common-mode rejection. 22
6.4.13 Maximum instrument noise. 23
6.5 Output. 24
6.6 Digitization. 24
Annex A (informative) Principle of frequency beat method . 25
Annex B (informative) Method of measurement of the linearity range between an output O and an
input I . 27
Annex C (normative) Alternative measurement of the input impedance . 28
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 15548-1 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 138, Non-destructive Testing, in collaboration with ISO Technical Committee TC 135, Non-
destructive Testing, Subcommittee SC 4, Eddy current methods, in accordance with the Agreement on
technical cooperation between ISO and CEN (Vienna Agreement).
ISO 15548 consists of the following parts, under the general title Non-destructive testing — Equipment for
eddy current examination:
⎯ Part 1: Instrument characteristics and verification
⎯ Part 2: Probe characteristics and verification
⎯ Part 3: System characteristics and verification
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SIST EN ISO 15548-1:2009
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SIST EN ISO 15548-1:2009
INTERNATIONAL STANDARD ISO 15548-1:2008(E)
Non-destructive testing — Equipment for eddy current
examination —
Part 1:
Instrument characteristics and verification
1 Scope
This part of ISO 15548 identifies the functional characteristics of a general-purpose eddy current instrument
and provides methods for their measurement and verification.
The evaluation of these characteristics permits a well-defined description and comparability of eddy current
equipment.
By careful choice of the characteristics, a consistent and effective eddy current examination system can be
designed for a specific application.
Where accessories are used, these are characterised using the principles of this part of ISO 15548.
This part of ISO 15548 gives neither the extent of verification nor acceptance criteria for the characteristics.
They are given in the application documents.
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.
ISO 12718, Non-destructive testing — Eddy current testing — Terminology
ISO 15549, Non-destructive testing — Eddy current testing — General principles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 12718 apply.
4 Eddy current instrument characteristics
4.1 General characteristics
4.1.1 Type of instrument
a) An instrument has a general-purpose application when the relationship between the measured quantity
and the display or output is established by the user. A range of probes can be connected to the
instrument. The instrument manufacturer shall provide details of the internal electrical characteristics, in
order that the user can design the examination system. The examination system shall be in accordance
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
with ISO 15549. The user shall be able to vary the value of frequency, gain, balance (unless an automatic
balance is used), phase, filters and gain and zero of the display.
b) An instrument is of specific application when the relationship between the measured quantity and the
display or output is explicitly defined in the range of application. The probe is specific to the instrument.
For this type of instrument, this part of ISO 15548 may be partially applied.
4.1.2 Power supply
The instrument can be powered by batteries or by the local AC power supply. The nominal values of voltage,
frequency and power consumption shall be stated, together with the tolerance for correct operation.
4.1.3 Safety
The instrument and its accessories shall meet the applicable safety regulations, for example, electrical hazard,
surface temperature, explosion, etc.
4.1.4 Technology
The instrument can be wholly analogue or partly analogue and partly digital.
The excitation can be single frequency, multifrequency, swept frequency or pulsed.
The instrument can be single or multichannel.
The instrument settings can be manual, remote controlled, stored or preset.
The instrument shall have component outputs and can be with or without a self-contained display.
4.1.5 Physical presentation
The instrument can be portable, cased or rack mounted, with the component parts integrated or modular.
The weight and size shall be specified for the instrument and its accessories.
The plugs and sockets shall be specified regarding type and pin interconnections.
The instrument model number and the serial number shall be clearly readable and located in a readily
accessible place.
4.1.6 Environmental effects
The warm-up time necessary for the instrument to reach stable operating conditions within specified limits
shall be stated.
The temperature, humidity and vibration ranges for normal use, storage and transport shall be specified for
the instrument and its accessories.
The instrument shall conform to relevant electromagnetic compatibility (EMC) regulations.
4.2 Electrical characteristics
4.2.1 General
The electrical characteristics of an instrument shall be evaluated after the warm-up time has elapsed.
The electrical characteristics are only valid for the stated operating conditions.
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
When relevant, the stability of the specified values with time, for specified environmental conditions, shall be
stated.
The electrical characteristics apply to various items of the functional block diagram of the instrument. Where
applicable, they are provided by the manufacturer. Some of these characteristics can be verified according to
the methodology described in Clause 6.
4.2.2 Functional block diagram
The functional block diagram of a typical general-purpose eddy current instrument is shown in Figure 1.
Figure 1 — Functional block diagram of an eddy current instrument
4.2.3 Generator unit
The source of excitation is the generator unit.
In the case of alternating excitation (sinusoidal, triangular, rectangular, etc.), the characteristics to be defined
are as follows:
⎯ type of generator: current or voltage;
⎯ type of excitation: single or multifrequency;
⎯ frequency setting: range, step size, deviation from nominal value;
⎯ harmonic distortion;
⎯ amplitude setting: range, step size, deviation from nominal value, maximum output voltage or current;
⎯ source impedance with frequency dependence.
In the case of multifrequency excitation, it shall be stated whether frequencies are injected simultaneously or
multiplexed, independent or related, and the multiplexing sequence shall be specified, when relevant.
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
4.2.4 Input stage characteristics
The input stage interfaces the probe to the instrument. It provides impedance matching and amplification, as
required.
The characteristics to be defined are as follows:
⎯ input impedance with frequency dependence;
⎯ gain setting range, step size, deviation from nominal value;
⎯ maximum input voltage;
⎯ common-mode operating parameters, when relevant.
4.2.5 Balance
Balance is the compensation of the signal to achieve a predetermined operating point, e.g. zero. The
compensation may be performed manually or automatically, at the input stage, or during HF signal
processing, or during demodulated signal processing, or on the display.
The characteristics to be defined are as follows:
⎯ maximum input range, which can be compensated;
⎯ residual value at balance (expressed as a percentage of a specified range, e.g. full-scale output).
4.2.6 High-frequency signal processing
4.2.6.1 HF filtering
Filters reduce the signal frequency content which can have an undesirable effect on the test result.
The filters used before demodulation are referred to as carrier frequency filters (HF filters). These are usually
band-pass filters which suppress any signal frequencies which do not correspond to the excitation frequency.
The characteristics to be defined are as follows:
⎯ gain;
⎯ bandwidth at 3 dB attenuation;
⎯ rate of attenuation;
⎯ transient response.
4.2.6.2 HF amplification
The characteristics to be defined are as follows:
⎯ gain setting range, step size, deviation from nominal value;
⎯ input signal range;
⎯ bandwidth;
⎯ output saturation level.
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
4.2.6.3 Demodulation
Synchronous demodulation extracts the vector components from the HF signal.
For positive polarity of demodulation, a delay in the signal will cause the signal vector to rotate clockwise. The
polarity of demodulation shall be positive and shall be confirmed.
The characteristics to be defined are as follows:
⎯ wave shape of the reference signal, e.g. sine, square, pulse;
⎯ bandwidth for each wave shape of the reference signal;
⎯ phase-dependent amplitude deviations;
⎯ phase-dependent phase deviations.
Amplitude demodulation extracts the low-frequency amplitude variations from the HF signal.
4.2.7 Demodulated signal processing
4.2.7.1 Vector amplification
Vector amplification generally consists of two transmission channels of identical design. These channels
amplify the vector components produced by synchronous demodulation. In some instruments, these
components can be amplified with different gains.
The characteristics to be defined are as follows:
⎯ gain setting range, step size, deviation from nominal value;
⎯ input signal ranges;
⎯ bandwidth;
⎯ output saturation level.
4.2.7.2 LF filtering
The filters used after demodulation are referred to as low-frequency filters (LF filters). The bandwidth of the
filter is chosen to suit the application, e.g. wobble, surface speed, etc.
The characteristics to be defined are as follows:
⎯ gain;
⎯ bandwidth at 3 dB attenuation;
⎯ rate of attenuation;
⎯ transient response.
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
4.2.7.3 Phase setting
Phase setting permits rotation of the demodulated signal vector on the complex plane display.
The characteristics to be defined are as follows:
⎯ range;
⎯ step size;
⎯ amplitude variation of the signal vector with phase setting;
⎯ deviation of indicated phase rotation from actual phase rotation.
4.2.8 Output and signal display
The type of display can be an indicator display, or a hard-copy display, or a screen display.
The type of presentation can be, for example, complex plane, ellipse, time-synchronous, frequency spectrum,
imaging.
The related characteristics to be defined include:
⎯ size;
⎯ graticule divisions, major and minor;
⎯ full-scale-display voltage range or time range;
⎯ transfer factor e.g. volts/division;
⎯ linearity;
⎯ bandwidth.
The output can be analogue, digitised or logical.
The characteristics of analogue outputs to be defined are as follows:
⎯ voltage or current range;
⎯ output impedance;
⎯ linearity;
⎯ bandwidth.
The characteristics of digitised outputs to be defined are as follows:
⎯ data protocol;
⎯ serial or parallel;
⎯ voltage and current levels;
⎯ speed and format;
⎯ sampling rate;
⎯ analogue/digital A/D resolution, range and linearity.
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SIST EN ISO 15548-1:2009
ISO 15548-1:2008(E)
The characteristics of logical outputs to be defined are as follows:
⎯ voltage and current levels;
⎯ settling delay;
⎯ hysteresis;
⎯ actively high or low.
4.2.9 Digitization
4.2.9.1 General
Whenever digitization is performed, the following characteristics shall be defined:
⎯ stage of digitization in the signal processing;
⎯ digitization technique;
⎯ A/D resolution;
⎯ sampling rate.
The information supplied by the manufacturer shall therefore include data on the parameters in 4.2.9.2 to
4.2.9.5.
4.2.9.2 Stage of digitization
Digitization may be performed either before or after signal demodulation.
4.2.9.3 Digitization technique
Digitization can be performed using an internal clock or an external encoder.
4.2.9.4 A/D Resolution
Resolution is the nominal valu
...
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