Direct acting indicating analogue electrical measuring instruments and their accessories - Part 1: Definitions and general requirements common to all parts

IEC 60051-1:2016 specifies definitions and general requirements for direct acting indicating analogue electrical measuring instruments and their accessories. This sixth edition cancels and replaces the fifth edition published in 1997. This edition constitutes a technical revision.

Direkt wirkend anzeigende analoge elektrische Messgeräte und ihr Zubehör - Teil 1: Definitionen und allgemeine Anforderungen für alle Teile

Appareils de mesure électriques indicateurs analogiques à action directe et leurs accessoires - Partie 1: Définitions et exigences générales communes à toutes les parties

L'IEC 60051-1:2016 spécifie les définitions et les exigences générales relatives aux appareils de mesure électriques indicateurs analogiques à action directe et leurs accessoires. Cette sixième édition annule et remplace la cinquième édition parue en 1997. Cette édition constitue une révision technique.

Neposredni kazalni analogni električni merilni instrumenti in njihov pribor - 1. del: Definicije in splošne zahteve, skupne vsem delom (IEC 60051-1:2016)

Ta del standarda IEC 60051 določa definicije in splošne zahteve za neposredne kazalne analogne električne merilne instrumente in njihov pribor.
Ta del se uporablja za neposredne kazalne analogne električne merilne instrumente, kot so:
• ampermetri in voltmetri;
• vatmetri in varmetri;
• merilniki frekvence z indikatorjem in vibrirajoči merilniki;
• merilniki faze, merilniki močnostnega faktorja in sinhroskopi;
• ohmmetri (merilniki impedance) in merilniki konduktance;
• večfunkcijski instrumenti zgoraj navedenih tipov.
Uporablja se tudi za:
• določen pribor, ki se uporablja s temi instrumenti, kot na primer:
– uporniki;
– zaporedni uporniki in impedančni elementi;
• kombinacije instrumentov in pribora, če so bile opravljene prilagoditve za to kombinacijo;
• neposredni kazalni električni merilni instrument, pri katerem oznake na skali ne ustrezajo neposredno vhodni električni količini, če je razmerje med njima znano;
• instrumente in pribor z elektronskimi napravami v merilnih in/ali pomožnih tokokrogih.
Te skupine standardov se ne uporabljajo za:
• instrumente za poseben namen, ki so zajeti v lastnih standardih IEC;
• naprave za poseben namen, ki so zajete v lastnih standardih IEC, kadar so uporabljene kot pribor.
Ta standard ne določa zahtev glede dimenzij instrumentov ali pribora (za prvo glej standard IEC 60473).

General Information

Status
Published
Publication Date
27-Apr-2017
Current Stage
6060 - Document made available
Due Date
28-Apr-2017
Completion Date
28-Apr-2017

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SLOVENSKI STANDARD
SIST EN 60051-1:2017
01-september-2017
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SIST EN 60051-1:2000

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Direct acting indicating analogue electrical measuring instruments and their accessories -

Part 1: Definitions and general requirements common to all parts (IEC 60051-1:2016)

Direkt anzeigende analoge elektrische Messgeräte und ihr Zubehör - Teil 1: Definitionen

und allgemeine Anforderungen für alle Teile (IEC 60051-1:2016)

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Ta slovenski standard je istoveten z: EN 60051-1:2017
ICS:
01.040.17 Meroslovje in merjenje. Metrology and measurement.
Fizikalni pojavi (Slovarji) Physical phenomena
(Vocabularies)
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
SIST EN 60051-1:2017 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 60051-1:2017
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SIST EN 60051-1:2017
EUROPEAN STANDARD EN 60051-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2017
ICS 17.220.20 Supersedes EN 60051-1:1998
English Version
Direct acting indicating analogue electrical measuring
instruments and their accessories - Part 1: Definitions and
general requirements common to all parts
(IEC 60051-1:2016)

Appareils de mesure électriques indicateurs analogiques à Direkt anzeigende analoge elektrische Messgeräte und ihr

action directe et leurs accessoires - Partie 1: Définitions et Zubehör - Teil 1: Definitionen und allgemeine

exigences générales communes à toutes les parties Anforderungen für alle Teile
(IEC 60051-1:2016) (IEC 60051-1:2016)

This European Standard was approved by CENELEC on 2016-03-09. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, 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: Avenue Marnix 17, B-1000 Brussels

© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN 60051-1:2017 E
---------------------- Page: 3 ----------------------
SIST EN 60051-1:2017
EN 60051-1:2017
European foreword

The text of document 85/521/FDIS, future edition 6 of IEC 60051-1, prepared by IEC/TC 85

"Measuring equipment for electrical and electromagnetic quantities" was submitted to the IEC-

CENELEC parallel vote and approved by CENELEC as EN 60051-1:2017.
The following dates are fixed:
(dop) 2017-10-28
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2020-04-28
• latest date by which the national
standards conflicting with the
document have to be withdrawn
This document supersedes EN 60051-1:1998.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such

patent rights.

This document has been prepared under a mandate given to CENELEC by the European Commission

and the European Free Trade Association.
Endorsement notice

The text of the International Standard IEC 60051-1:2016 was approved by CENELEC as a European

Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standard indicated :

IEC 60359:2001 NOTE Harmonized as EN 60359:2002.
IEC 61557-12:2007 NOTE Harmonized as EN 61557-12:2008.
IEC 62052-11:2003 NOTE Harmonized as EN 62052-11:2003.
IEC 62586-1:2013 NOTE Harmonized as EN 62586-1:2014.
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SIST EN 60051-1:2017
- EN 60051-1:2017
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

NOTE 1 When 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 60051-9 - Direct acting indicating analogue electrical-EN 60051-9 -
measuring instruments and their
accessories -- Part 9: Recommended test
methods
IEC 60359 2001 Electrical and electronic measurement EN 60359 2002
equipment - Expression of performance
IEC 60529 2013 Degrees of protection provided by - -
enclosures (IP Code)
+ A1 1995 - -

IEC 60721-3-3 1994 Classification of environmental conditions -EN 60721-3-3 1995

- Part 3: Classification of groups of
environmental parameters and their
severities -- Section 3: Stationary use at
weatherprotected locations
+ A2 1996 + A2 1997

IEC 60721-3-7 1995 Classification of environmental conditions -EN 60721-3-7 1995

- Part 3: Classification of groups of
environmental parameters and their
severities -- Section 7: Portable and non-
stationary use
+ A1 1996 + A1 1997
IEC 61010-1 2010 Safety requirements for electrical EN 61010-1 2010
equipment for measurement, control and
laboratory use -- Part 1: General
requirements
IEC 61010-2-030 2010 Safety requirements for electrical EN 61010-2-030 2010
equipment for measurement, control and
laboratory use -- Part 2-030: Particular
requirements for testing and measuring
circuits
IEC 61326-1 2012 Electrical equipment for measurement, EN 61326-1 2013
control and laboratory use - EMC
requirements -- Part 1: General
requirements
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SIST EN 60051-1:2017
EN 60051-1:2017
IEC 61326-2-1 - Electrical equipment for measurement, EN 61326-2-1 -
control and laboratory use - EMC
requirements -- Part 2-1: Particular
requirements - Test configurations,
operational conditions and performance
criteria for sensitive test and measurement
equipment for EMC unprotected
applications
ISO 780 - Packaging - Pictorial marking for handling EN ISO 780 -
of goods
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SIST EN 60051-1:2017
IEC 60051-1
Edition 6.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 1: Definitions and general requirements common to all parts
Appareils de mesure électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 1: Définitions et exigences générales communes à toutes les parties
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20 ISBN 978-2-8322-3162-3

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 60051-1:2017
– 2 – IEC 60051-1:2016 © IEC 2016
CONTENTS

FOREWORD ......................................................................................................................... 5

INTRODUCTION ................................................................................................................... 7

1 Scope ............................................................................................................................ 8

2 Normative references..................................................................................................... 8

3 Terms and definitions .................................................................................................... 9

3.1 General terms ....................................................................................................... 9

3.2 Description of instruments according to their method of operation ........................ 13

3.3 Constructional features of instruments ................................................................. 14

3.4 Characteristic features of instruments .................................................................. 16

3.5 Characteristic values ........................................................................................... 17

3.6 Influence quantity, reference conditions, nominal range of use and

preconditioning ................................................................................................... 17

3.7 Uncertainty and variations ................................................................................... 19

3.8 Accuracy, accuracy class and class index ............................................................ 21

3.9 Test .................................................................................................................... 21

4 Description, classification and compliance .................................................................... 22

4.1 Description.......................................................................................................... 22

4.1.1 Description according to methods of operation or nature ............................... 22

4.1.2 Description according to environmental conditions ........................................ 22

4.1.3 Description according to mechanical conditions ............................................ 22

4.1.4 Description according to degrees of protection .............................................. 22

4.2 Classification ...................................................................................................... 22

4.3 Compliance with the requirements of this standard ............................................... 23

5 Requirements .............................................................................................................. 23

5.1 Reference conditions ........................................................................................... 23

5.2 Limits of intrinsic uncertainty, fiducial value ......................................................... 23

5.2.1 Limits of intrinsic uncertainty ........................................................................ 23

5.2.2 Correspondence between intrinsic uncertainty and accuracy class ................ 23

5.2.3 Fiducial value............................................................................................... 23

5.3 Nominal range of use and variations .................................................................... 25

5.3.1 Nominal range of use ................................................................................... 25

5.3.2 Limits of variations ....................................................................................... 27

5.3.3 Conditions for the determination of variations ............................................... 28

5.4 Operating uncertainty, overall system uncertainty and variations .......................... 28

5.5 Electrical requirements ........................................................................................ 28

5.5.1 Electrical safety requirements ...................................................................... 28

5.5.2 Self-heating ................................................................................................. 28

5.5.3 Permissible overloads .................................................................................. 29

5.5.4 Limiting range of temperature ....................................................................... 29

5.5.5 Deviation from zero ...................................................................................... 29

5.5.6 Electromagnetic compatibility (EMC) ............................................................ 29

5.6 Constructional requirements ................................................................................ 30

5.6.1 General constructional requirements ............................................................ 30

5.6.2 Damping ...................................................................................................... 30

5.6.3 Sealing to prevent access ............................................................................ 30

5.6.4 Scales ......................................................................................................... 31

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SIST EN 60051-1:2017
IEC 60051-1:2016 © IEC 2016 – 3 –

5.6.5 Stopper ........................................................................................................ 32

5.6.6 Preferred values .......................................................................................... 32

5.6.7 Adjusters, mechanical and/or electrical ......................................................... 32

5.6.8 Effects of vibration and shock ....................................................................... 33

5.6.9 Degrees of protection provided by enclosure ................................................ 33

5.6.10 Terminals ..................................................................................................... 34

6 Information, markings and symbols .............................................................................. 34

6.1 Information.......................................................................................................... 34

6.2 Markings, symbols and their locations .................................................................. 35

6.3 Markings relating to the reference values and nominal ranges of use of

influence quantities ............................................................................................. 36

6.4 The symbols for marking instruments and accessories ......................................... 36

6.5 Markings and symbols for terminals ..................................................................... 45

6.5.1 Requirements for markings ........................................................................... 45

6.5.2 Earthing (grounding) terminals ..................................................................... 45

6.5.3 Measuring circuit terminals ........................................................................... 45

6.5.4 Special markings for terminals ...................................................................... 45

6.6 Instructions for use .............................................................................................. 45

7 Package ...................................................................................................................... 46

8 Test rules .................................................................................................................... 46

8.1 Type of test ......................................................................................................... 46

8.2 Type tests ........................................................................................................... 46

8.3 Routine tests ....................................................................................................... 46

8.4 Recurrent tests ................................................................................................... 46

8.5 Nonconformity classification ................................................................................ 47

8.6 Judgement of test results .................................................................................... 47

Annex A (normative) Limits of intrinsic uncertainty and variations ....................................... 48

Annex B (informative) Relationship between ambient temperature and relative

humidity.............................................................................................................................. 51

Annex C (informative) Estimation of uncertainties ............................................................... 52

C.1 Uncertainties in this standard .............................................................................. 52

C.2 Operating uncertainty .......................................................................................... 52

C.2.1 General ....................................................................................................... 52

C.2.2 Estimating absolute operating uncertainty according to type test results ........ 52

C.2.3 Estimating absolute operating uncertainty according to limit of intrinsic
uncertainty and limit of variations due to every influence specified by

this standard ................................................................................................ 53

C.3 Overall system uncertainty .................................................................................. 54

C.4 Fiducial operating uncertainty .............................................................................. 54

Annex D (normative) Routine Tests .................................................................................... 55

Bibliography ....................................................................................................................... 56

Figure 1 – Measuring range 10 A to 50 A ............................................................................. 31

Figure 2 – Measuring range 80 V to 110 V ........................................................................... 32

Figure 3 – Measuring ranges 0,06 MΩ to 0,4 M Ω and 0,1 MΩ to 2 MΩ ................................ 32

Figure A.1 – Effect of temperature ....................................................................................... 48

Figure A.2 – Effect of temperature ....................................................................................... 49

Figure B.1 – Relationship between ambient temperature and relative humidity ..................... 51

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SIST EN 60051-1:2017
– 4 – IEC 60051-1:2016 © IEC 2016

Figure C.1 – Different kinds of uncertainty ........................................................................... 52

Table 1 – Minimum IP requirements .................................................................................... 22

Table 2 – Reference conditions and tolerances for testing purposes relating to the

influence quantities ............................................................................................................. 24

Table 3 – Limits of the nominal range of use and permissible variations ............................... 26

Table 4 – The diameters of conductive screw and the diameters or the area of contact

surface ............................................................................................................................... 34

Table 5 – Units, quantities and SI prefixes ........................................................................... 37

Table 6 – Symbols for marking instruments and accessories ................................................ 38

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SIST EN 60051-1:2017
IEC 60051-1:2016 © IEC 2016 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 1: Definitions and general requirements common to all parts
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 60051-1 has been prepared by IEC technical committee 85:

Measuring equipment for electrical and electromagnetic quantities.

This sixth edition cancels and replaces the fifth edition published in 1997. This edition

constitutes a technical revision.

This edition includes the following significant technical changes with respect to the previous

edition:
– adding the EMC requirements;

– updating the safety symbols and requirements according to new IEC 61010 series;

– replacing the concept of “error” to the concept of “uncertainty”;

– adding service environment classification and classification by method of operation,

mechanical condition and the degrees of protection;
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SIST EN 60051-1:2017
– 6 – IEC 60051-1:2016 © IEC 2016

– adding the requirements for transport and storage of instruments and accessories

according to IEC 60359;
– updating the Annexes to provide more information.
The text of this standard is based on the following documents:
FDIS Report on voting
85/521/FDIS 85/536/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60051 series, published under the general title Direct acting

indicating analogue electrical measuring instruments and their accessories, can be found on

the IEC website.

The committee has decided that the contents of this publication will remain unchanged until

the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data

related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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SIST EN 60051-1:2017
IEC 60051-1:2016 © IEC 2016 – 7 –
INTRODUCTION

IEC 60051 is published in separate parts according to the following structure and under the

general title Direct acting indicating analogue electrical measuring instruments and their

accessories.
Part 1: Definitions and General Requirements Common to all Parts.
Part 2: Special Requirements for Ammeters and Voltmeters.
Part 3: Special Requirements for Wattmeters and Varmeters.
Part 4: Special Requirements for Frequency Meters.

Part 5: Special Requirements for Phase Meters, Power Factor Meters and Synchroscopes.

Part 6: Special Requirements for Ohmmeters (Impedance Meters) and Conductance Meters.

Part 7: Special Requirements for Multi-function Instruments.
Part 8: Special Requirements for Accessories.
Part 9: Recommended Test Methods.

Parts 2 to 9 are not complete in themselves and shall be read in conjunction with this Part 1.

All of these parts are arranged in the same format and a standard relationship between

subject and clause number is maintained throughout. This re-arrangement will assist the

reader of IEC 60051 to distinguish information relating to the different types of instruments.

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SIST EN 60051-1:2017
– 8 – IEC 60051-1:2016 © IEC 2016
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 1: Definitions and general requirements common to all parts
1 Scope

This part of IEC 60051 specifies definitions and general requirements for direct acting

indicating analogue electrical measuring instruments and their accessories.

This part applies to direct acting indicating analogue electrical measuring instruments, such

as:
• ammeters and voltmeters;
• wattmeters and varmeters;
• frequency meters of pointer and vibrating-reed types;
• phasemeters, power-factor meters and synchroscopes;
• ohmmeters(impedance meters) and conductance meters;
• multi-function instruments of the above types.
It also applies to:
• certain accessories used with these instruments, such as:
– shunts;
– series resistors and impedance elements;

• combination of the instruments and the accessories provided that the adjustments have

been made for the combination;

• direct acting indicating electrical measuring instrument whose scale marks do not

correspond directly to its electrical input quantity, provided that the relationship between

them is known;

• instruments and accessories having electronic devices in their measuring and/or auxiliary

circuits.
These series standards do not apply to:
• special purpose instruments which are covered by their own IEC standards;

• special purpose devices which are covered by their own IEC standards when they are

used as accessories.

This standard does not specify requirements concerning dimensions of instruments or

accessories (for the former, see IEC 60473).
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and

are indispensable for its application. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any
amendments) applies.
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SIST EN 60051-1:2017
IEC 60051-1:2016 © IEC 2016 – 9 –
IEC 60051-9, Direct acting indicating analogue electri
...

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