Direct acting indicating analogue electrical measuring instruments and their accessories - Part 7: Special requirements for multi-function instruments

IEC 60051-7:2017 applies to multi-function analogue instruments.
This document also applies to non-interchangeable accessories (as defined in 3.1.23 of IEC 60051-1:2016) used with multi-function analogue instruments.
This fifth edition cancels and replaces the fourth edition published in 1984. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) updating of content in line with new editions of IEC 60051-1 and IEC 60051-9;
b) addition of Annex A to specify the nonconformity classification of test items.

Appareils mesureurs électriques indicateurs analogiques à action directe et leurs accessoires - Partie 7: Exigences particulières pour les appareils à fonctions multiples

L'IEC 60051-7:2017 s'applique aux appareils analogiques à fonctions multiples.
Le présent document s'applique également aux accessoires non interchangeables (définis en 3.1.23 de l'IEC 60051-1:2016) utilisés avec les appareils analogiques à fonctions multiples.
Cette cinquième édition annule et remplace la quatrième édition parue en 1984. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) mise à jour du contenu en fonction des nouvelles éditions de l'IEC 60051-1 et de l'IEC 60051-9;
b) ajout de l'Annexe A pour spécifier la classification des non-conformités des éléments d'essai.

General Information

Status
Published
Publication Date
14-Dec-2017
Current Stage
PPUB - Publication issued
Completion Date
15-Dec-2017
Ref Project

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IEC 60051-7
Edition 5.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 7: Special requirements for multi-function instruments
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 7: Exigences particulières pour les appareils à fonctions multiples
IEC 60051-7:2017-12(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60051-7
Edition 5.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 7: Special requirements for multi-function instruments
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 7: Exigences particulières pour les appareils à fonctions multiples
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20 ISBN 978-2-8322-5190-4

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
---------------------- Page: 3 ----------------------
– 2 – IEC 60051-7:2017 © IEC 2017
CONTENTS

FOREWORD ........................................................................................................................... 4

INTRODUCTION ..................................................................................................................... 6

1 Scope .............................................................................................................................. 7

2 Normative references ...................................................................................................... 7

3 Terms and definitions ...................................................................................................... 7

4 Description, classification and compliance ....................................................................... 7

4.1 Description ............................................................................................................. 7

4.2 Classification .......................................................................................................... 7

4.3 Compliance with the requirements of this standard ................................................. 7

5 Requirements .................................................................................................................. 8

5.1 Reference conditions .............................................................................................. 8

5.2 Limits of intrinsic uncertainty, fiducial value ............................................................ 8

5.2.1 Limits of intrinsic uncertainty ........................................................................... 8

5.2.2 Correspondence between intrinsic uncertainty and accuracy class .................. 8

5.2.3 Fiducial value .................................................................................................. 8

5.3 Nominal range of use and variations ....................................................................... 8

5.3.1 Nominal range of use ....................................................................................... 8

5.3.2 Limits of variations........................................................................................... 8

5.3.3 Conditions for the determination of variations .................................................. 8

5.4 Operating uncertainty, overall system uncertainty and variations ............................ 8

5.5 Electrical requirements ........................................................................................... 8

5.5.1 Electrical safety requirements .......................................................................... 8

5.5.2 Self-heating ..................................................................................................... 8

5.5.3 Permissible overloads ...................................................................................... 9

5.5.4 Limiting range of temperature .......................................................................... 9

5.5.5 Deviation from zero ......................................................................................... 9

5.5.6 Electromagnetic compatibility (EMC) ............................................................... 9

5.6 Constructional requirements ................................................................................... 9

5.6.1 General constructional requirements ............................................................... 9

5.6.2 Damping .......................................................................................................... 9

5.6.3 Sealing to prevent access ................................................................................ 9

5.6.4 Scales ............................................................................................................. 9

5.6.5 Stopper............................................................................................................ 9

5.6.6 Preferred values ............................................................................................ 10

5.6.7 Adjusters, mechanical and/or electrical .......................................................... 10

5.6.8 Effects of vibration and shock ........................................................................ 10

5.6.9 Degrees of protection provided by enclosure ................................................. 10

5.6.10 Terminals ...................................................................................................... 10

6 Information, markings and symbols ................................................................................ 10

6.1 Information ........................................................................................................... 10

6.2 Markings, symbols and their locations ................................................................... 10

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

influence quantities ............................................................................................... 10

6.4 The symbols for marking instruments and accessories .......................................... 10

6.5 Markings and symbols for terminals ...................................................................... 10

6.5.1 Requirements for markings ............................................................................ 10

---------------------- Page: 4 ----------------------
IEC 60051-7:2017 © IEC 2017 – 3 –

6.5.2 Earthing (grounding) terminals ....................................................................... 10

6.5.3 Measuring circuit terminals ............................................................................ 10

6.5.4 Special markings for terminals ....................................................................... 11

6.6 Instructions for use ............................................................................................... 11

7 Package ........................................................................................................................ 11

8 Test rules ...................................................................................................................... 11

Annex A (normative) Nonconformity classification of tests ................................................... 12

Bibliography .......................................................................................................................... 13

---------------------- Page: 5 ----------------------
– 4 – IEC 60051-7:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL MEASURING
INSTRUMENTS AND THEIR ACCESSORIES –
Part 7: Special requirements for multi-function instruments
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

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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

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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 60051-7 has been prepared by IEC technical committee 85:

Measuring equipment for electrical and electromagnetic quantities.

This fifth edition cancels and replaces the fourth edition published in 1984. This edition

constitutes a technical revision.

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

edition:
a) updating of content in line with new editions of IEC 60051-1 and IEC 60051-9;

b) addition of Annex A to specify the nonconformity classification of test items.

---------------------- Page: 6 ----------------------
IEC 60051-7:2017 © IEC 2017 – 5 –
The text of this International Standard is based on the following documents:
CDV Report on voting
85/560/CDV 85/583A/RVC

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 International Standard is to be used in conjunction with IEC 60051-1:2016.

This document 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 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.
---------------------- Page: 7 ----------------------
– 6 – IEC 60051-7:2017 © IEC 2017
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

IEC 60051-7 is not complete in itself and is read in conjunction with IEC 60051-1.

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

subject and clause number is maintained throughout these parts. This arrangement will assist

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

---------------------- Page: 8 ----------------------
IEC 60051-7:2017 © IEC 2017 – 7 –
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL MEASURING
INSTRUMENTS AND THEIR ACCESSORIES –
Part 7: Special requirements for multi-function instruments
1 Scope
This part of IEC 60051 applies to multi-function analogue instruments.

This document also applies to non-interchangeable accessories (as defined in 3.1.23 of

IEC 60051-1:2016) used with multi-function analogue instruments.
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 60051-1:2016, Direct acting indicating analogue electrical measuring instruments and

their accessories – Part 1: Definitions and general requirements common to all parts

3 Terms and definitions
See IEC 60051-1:2016.
4 Description, classification and compliance
4.1 Description
See IEC 60051-1:2016.
4.2 Classification
See IEC 60051-1:2016.

Each function of a multi-function instrument shall be classified in one of the accuracy classes

denoted by the class indices as given in 4.2 of the part relevant to that function.

Each function may have a different class index.

DC and AC are considered to be different measuring functions as are the measurement of

current and voltage.

Some ranges of a function may have a different class index from the other ranges.

4.3 Compliance with the requirements of this standard
See IEC 60051-1:2016.
---------------------- Page: 9 ----------------------
– 8 – IEC 60051-7:2017 © IEC 2017
5 Requirements
5.1 Reference conditions

See IEC 60051-1:2016, for general requirements and 5.1 of the relevant part for each function

for special requirements, if any.
5.2 Limits of intrinsic uncertainty, fiducial value
5.2.1 Limits of intrinsic uncertainty

See IEC 60051-1:2016, for general requirements and 5.2.1 of the relevant part for each

function for special requirements, if any.
5.2.2 Correspondence between intrinsic uncertainty and accuracy class

See IEC 60051-1:2016, for general requirements and 5.2.2 of the relevant part for each

function for special requirements, if any.
5.2.3 Fiducial value

The fiducial value for each function of a multi-function instrument shall be as given in 5.2.3 of

the part relevant to that function.
5.3 Nominal range of use and variations
5.3.1 Nominal range of use

See Table 3 of IEC 60051-1:2016. The limits of the nominal range of use shall be given in the

specific table for the relevant part.
5.3.2 Limits of variations

See IEC 60051-1:2016, for general requirements and 5.3.2 of the relevant part for each

function for special requirements, if any.
5.3.3 Conditions for the determination of variations

See IEC 60051-1:2016, for general requirements and 5.3.3 of the relevant part for each

function for special requirements, if any.
5.4 Operating uncertainty, overall system uncertainty and variations
See IEC 60051-1:2016.
5.5 Electrical requirements
5.5.1 Electrical safety requirements
See IEC 60051-1:2016.
5.5.2 Self-heating

See IEC 60051-1:2016, for general requirements and 5.5.2 of the relevant part for each

function for special requirements, if any.

However, if a multi-function instrument cannot meet all of the requirements of 5.5.2 of

IEC 60051-1:2016 on one or more ranges, the manufacturer shall mark symbol F-31 given in

Table 6 of IEC 60051-1:2016 (see Clause 6 of IEC 60051-1:2016) on the dial or on a part

---------------------- Page: 10 ----------------------
IEC 60051-7:2017 © IEC 2017 – 9 –

which is visible while the instrument is in use and shall give details in a separate document of

the requirements which cannot be met.
5.5.3 Permissible overloads

See IEC 60051-1:2016, for general requirements and 5.5.3 of the relevant part for each

function for special requirements, if any.

However, if a multi-function instrument cannot meet all of the requirements of 5.5.3 of

IEC 60051-1:2016 on one or more ranges, the manufacturer shall mark symbol F-31 given in

Table 6 of IEC 60051-1:2016 (see Clause 6 of IEC 60051-1:2016) on the dial or on a part

which is visible while the instrument is in use and shall give details in a separate document of

the requirements which cannot be met.
5.5.4 Limiting range of temperature
See IEC 60051-1:2016.
5.5.5 Deviation from zero

Special requirements and tests for deviation from zero and for return to zero are given in 5.5.5

of the part relevant to each function.
5.5.6 Electromagnetic compatibility (EMC)
See IEC 60051-1:2016.
5.6 Constructional requirements
5.6.1 General constructional requirements
See IEC 60051-1:2016.
5.6.2 Damping

See IEC 60051-1:2016 for general requirements and 5.6.2 of the relevant part for each

function for special requirements, if any.

However, if a multi-function instrument cannot meet all of the requirements of 5.6.2 of

IEC 60051-1:2016 on one or more ranges, the manufacturer shall mark symbol F-31 given in

Table 6 of IEC 60051-1:2016 (see Clause 6 of IEC 60051-1:2016) on the dial or on a part

which is visible while the instrument is in use and shall give details in a separate document of

the requirements which cannot be met.
5.6.3 Sealing to prevent access
See IEC 60051-1:2016.
5.6.4 Scales
See IEC 60051-1:2016.
5.6.5 Stopper
See IEC 60051-1:2016.
---------------------- Page: 11 ----------------------
– 10 – IEC 60051-7:2017 © IEC 2017
5.6.6 Preferred values

Special requirements concerning preferred values are given in 5.6.6 of the part relevant to

each function.
5.6.7 Adjusters, mechanical and/or electrical
See IEC 60051-1:2016.
5.6.8 Effects of vibration and shock
See IEC 60051-1:2016.
5.6.9 Degrees of protection provided by enclosure
See IEC 60051-1:2016.
5.6.10 Terminals
See IEC 60051-1:2016.
6 Information, markings and symbols
6.1 Information
See IEC 60051-1:2016.
6.2 Markings, symbols and their locations
See IEC 60051-1:2016.

However, if it is unpractical to mark on the dial all of the information that is required by 6.2 of

IEC 60051-1:2016, the manufacturer shall mark symbol F-31 given in Table 6 of

IEC 60051-1:2016 (see Clause 6 of IEC 60051-1:2016) on the dial or on a part which is visible

while the instrument is in use and shall give in a separate document the information which is

not marked.

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

quantities
See IEC 60051-1:2016.
6.4 The symbols for marking instruments and accessories
See IEC 60051-1:2016.
6.5 Markings and symbols for terminals
6.5.1 Requirements for markings
See IEC 60051-1:2016.
6.5.2 Earthing (grounding) terminals
See IEC 60051-1:2016.
6.5.3 Measuring circuit terminals
See IEC 60051-1:2016.
---------------------- Page: 12 ----------------------
IEC 60051-7:2017 © IEC 2017 – 11 –
6.5.4 Special markings for terminals
All terminals shall be marked to ensure that they can be uniquely identified.

If a terminal is used as the positive terminal of a DC current or voltage measuring function, it

shall be marked using symbol F-39 (+) given in Table 6 of IEC 60051-1:2016 (see Clause 6 of

IEC 60051-1:2016), or the terminal and/or its immediate surround shall be coloured red. This

requirement applies no matter what its use may be with any other function.
6.6 Instructions for use
See IEC 60051-1:2016.
7 Package
See IEC 60051-1:2016.
8 Test rules
See IEC 60051-1:2016.

The recommended nonconformity classification of tests refers to Table A.1 of the part relevant

to each function.

The method of acceptance inspection may be agreed between the manufacturer and the

customer.
---------------------- Page: 13 ----------------------
– 12 – IEC 60051-7:2017 © IEC 2017
Annex A
(normative)
Nonconformity classification of tests

The recommended nonconformity classification of tests refers to Table A.1 of the part relevant

to each function.
---------------------- Page: 14 ----------------------
IEC 60051-7:2017 © IEC 2017 – 13 –
Bibliography

IEC 60051-9 , Direct acting indicating analogue electrical measuring instruments and their

accessories – Part 9: Recommended test methods
___________
Under preparation.
---------------------- Page: 15 ----------------------
– 14 – IEC 60051-7:2017 © IEC 2017
SOMMAIRE

AVANT-PROPOS .................................................................................................................. 16

INTRODUCTION ................................................................................................................... 18

1 Domaine d'application ................................................................................................... 19

2 Références normatives .................................................................................................. 19

3 Termes et définitions ..................................................................................................... 19

4 Description, classification et conformité ......................................................................... 19

4.1 Description ........................................................................................................... 19

4.2 Classification ........................................................................................................ 19

4.3 Conformité aux exigences de la présente norme ................................................... 20

5 Exigences ...................................................................................................................... 20

5.1 Conditions de référence ........................................................................................ 20

5.2 Limites de l'incertitude intrinsèque, valeur de repère .............................................

...

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