Direct acting indicating analogue electrical measuring instruments and their accessories - Part 2: Special requirements for ammeters and voltmeters

IEC 60051-2:2018 applies to direct acting indicating ammeters and voltmeters having an analogue display.
It also applies to:
• direct acting indicating ammeters and voltmeters whose scale marks do not correspond directly to their electrical input quantity, provided that the relationship between them is known;
• direct acting indicating ammeters and voltmeters and accessories having electronic devices in their measuring and/or auxiliary circuits.
This document does 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.
IEC 60051-2:2018 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 item.
This International Standard is to be used in conjunction with IEC 60051-1:2016.

Appareils mesureurs électriques indicateurs analogiques à action directe et leurs accessoires - Partie 2: Exigences particulières pour les ampèremètres et les voltmètres

IEC 60051-2:2018 s'applique aux ampèremètres et voltmètres indicateurs analogiques à action directe.
Elle s'applique également aux:
• ampèremètres et voltmètres indicateurs à action directe dont les repères de l'échelle ne correspondent pas directement à la grandeur électrique appliquée à l'entrée de l'appareil, à condition que la relation entre ceux-ci soit connue;
• ampèremètres et voltmètres indicateurs à action directe et leurs accessoires qui comportent des dispositifs électroniques dans leurs circuits de mesure et/ou auxiliaires.
Ce document ne s'applique pas aux:
• appareils spéciaux couverts par leurs propres normes IEC;
• dispositifs spéciaux couverts par leurs propres normes IEC, lorsqu'ils sont utilisés en tant qu'accessoires.
IEC 60051-2:2018 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.
L'IEC 60051-2 n'est pas complète en soi et est utilisée conjointement avec l'IEC 60051-1.

General Information

Status
Published
Publication Date
29-Aug-2018
Current Stage
PPUB - Publication issued
Completion Date
30-Aug-2018
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IEC 60051-2
Edition 5.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 2: Special requirements for ammeters and voltmeters
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 2: Exigences particulières pour les ampèremètres et les voltmètres
IEC 60051-2:2018-08(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60051-2
Edition 5.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 2: Special requirements for ammeters and voltmeters
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 2: Exigences particulières pour les ampèremètres et les voltmètres
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20 ISBN 978-2-8322-5956-6

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 60051-2:2018 © IEC 2018
CONTENTS

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

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

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

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

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

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

5 Requirements .................................................................................................................. 7

5.1 Reference conditions .............................................................................................. 7

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 ....................................................................... 9

5.3.1 Nominal range of use ....................................................................................... 9

5.3.2 Limits of variations......................................................................................... 10

5.3.3 Conditions for the determination of variations ................................................ 10

5.4 Operating uncertainty, overall system uncertainty and variations .......................... 10

5.5 Electrical requirements ......................................................................................... 10

5.5.1 Electrical safety requirements ........................................................................ 10

5.5.2 Self-heating ................................................................................................... 10

5.5.3 Permissible overloads .................................................................................... 10

5.5.4 Limiting range of temperature ........................................................................ 12

5.5.5 Deviation from zero ....................................................................................... 12

5.5.6 Electromagnetic compatibility (EMC) ............................................................. 12

5.6 Constructional requirements ................................................................................. 12

5.6.1 General constructional requirements ............................................................. 12

5.6.2 Damping ........................................................................................................ 12

5.6.3 Sealing to prevent access .............................................................................. 13

5.6.4 Scales ........................................................................................................... 13

5.6.5 Stopper.......................................................................................................... 13

5.6.6 Preferred values ............................................................................................ 13

5.6.7 Adjusters, mechanical and/or electrical .......................................................... 14

5.6.8 Effects of vibration and shock ........................................................................ 14

5.6.9 Degrees of protection provided by enclosure ................................................. 14

5.6.10 Terminals ...................................................................................................... 14

6 Information, markings and symbols ................................................................................ 14

6.1 Information ........................................................................................................... 14

6.2 Markings, symbols and their locations ................................................................... 14

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

influence quantities ............................................................................................... 14

6.4 The symbols for marking instruments and accessories .......................................... 14

6.5 Markings and symbols for terminals ...................................................................... 14

6.5.1 Requirements for markings ............................................................................ 14

6.5.2 Earthing (grounding) terminals ....................................................................... 15

6.5.3 Measuring circuit terminals ............................................................................ 15

6.5.4 Special markings for terminals ....................................................................... 15

---------------------- Page: 4 ----------------------
IEC 60051-2:2018 © IEC 2018 – 3 –

6.6 Instructions for use ............................................................................................... 15

7 Package ........................................................................................................................ 15

8 Test rules ...................................................................................................................... 15

Annex A (normative) Nonconformity classification of tests ................................................... 16

Bibliography .......................................................................................................................... 17

Table 1 – Limits of the nominal range of use and permissible variations in addition to

those given in Table 3 of IEC 60051-1:2016 ............................................................................ 9

Table 2 – Overloads of short duration for ammeters and voltmeters ...................................... 12

Table A.1 – Nonconformity classification of tests .................................................................. 16

---------------------- Page: 5 ----------------------
– 4 – IEC 60051-2:2018 © IEC 2018
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 2: Special requirements for ammeters and voltmeters
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

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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 60051-2 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 60051-2:2018 © IEC 2018 – 5 –
The text of this International Standard is based on the following documents:
CDV Report on voting
85/555/CDV 85/578A/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 document has been drafted in accordance with the ISO/IEC Directives, Part 2.

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

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 60051-2:2018 © IEC 2018
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 60051-2 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 60051-2:2018 © IEC 2018 – 7 –
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 2: Special requirements for ammeters and voltmeters
1 Scope

This part of IEC 60051 applies to direct acting indicating ammeters and voltmeters having an

analogue display.
NOTE For multi-function instruments, see IEC 60051-7.
It also applies to:

• direct acting indicating ammeters and voltmeters whose scale marks do not correspond

directly to their electrical input quantity, provided that the relationship between them is

known;

• direct acting indicating ammeters and voltmeters and accessories having electronic

devices in their measuring and/or auxiliary circuits.
This document does 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.
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

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

accessories – Part 9: Recommended test methods

IEC 61869-2, Instrument transformers – Part 2: Additional requirements for current

transformers
3 Terms and definitions
See IEC 60051-1:2016.
4 Description, classification and compliance
See IEC 60051-1:2016.
5 Requirements
5.1 Reference conditions
See IEC 60051-1:2016.
---------------------- Page: 9 ----------------------
– 8 – IEC 60051-2:2018 © IEC 2018
5.2 Limits of intrinsic uncertainty, fiducial value
5.2.1 Limits of intrinsic uncertainty
See IEC 60051-1:2016.
5.2.2 Correspondence between intrinsic uncertainty and accuracy class
See IEC 60051-1:2016.
5.2.3 Fiducial value

5.2.3.1 The fiducial value for an ammeter or a voltmeter corresponds to the following.

5.2.3.2 The upper limit of the measuring range for the following:

• instruments with the mechanical and/or electrical zero at one end of the scale;

• instruments with the mechanical zero outside the scale irrespective of the position of the

electrical zero;

• instruments with the electrical zero outside the scale irrespective of the position of the

mechanical zero.

The class index is marked using Symbol E-1 given in Table 6 of IEC 60051-1:2016 (see

Clause 6 of IEC 60051-1:2016).
5.2.3.3 The sum of the electrical values:

The sum of the absolute values of the upper and lower limit of the measuring range when both

the mechanical and the electrical zeros are displaced within the scale.

The class index is marked using Symbol E-1 given in Table 6 of IEC 60051-1:2016 (see

Clause 6 of IEC 60051-1:2016).
5.2.3.4 The span for an instrument:

The span for an instrument whose scale marks do not correspond directly to its electrical

input quantity.

The class index is marked using Symbol E-4 given in Table 6 of IEC 60051-1:2016 (see

Clause 6 of IEC 60051-1:2016).

Subclause 5.2.3.4 does not apply to a voltmeter or ammeter designed to be used in

conjunction with a shunt, a series resistor (impedance) or an instrument transformer. These

instruments are to be treated in accordance with 5.2.3.2 or 5.2.3.3, as appropriate.

5.2.3.5 The fiducial value for an ammeter with overload scale or an expanded scale

voltmeter:

The fiducial value for an ammeter with overload scale or an expanded scale voltmeter

corresponds to 5.2.3.2 or 5.2.3.3, as appropriate. The measuring range of an ammeter with

overload scale is the upper limit of the non-overload part. The measuring range of an

expanded scale voltmeter is the lower limit of the expanded part.

5.2.3.6 The fiducial value for an instrument with a special arrangement of scale marks:

For an instrument whose scale has been arranged to produce a special arrangement of scale

marks, the fiducial value shall be as agreed between manufacturer and user. The fiducial

value does not have to be the same at all points on the scale.
---------------------- Page: 10 ----------------------
IEC 60051-2:2018 © IEC 2018 – 9 –
5.3 Nominal range of use and variations
5.3.1 Nominal range of use
See Table 1.
Table 1 – Limits of the nominal range of use and permissible
variations in addition to those given in Table 3 of IEC 60051-1:2016

Influence quantity Limits of nominal range of use Permissible variation expressed as a

unless otherwise marked percentage of class index
Ripple (45 Hz to 65 Hz and 90 Hz to 20 % 50 %
130 Hz) on DC measured quantity
for other than RMS responding
instruments
Distortion of AC Distortion factor Instruments without electronic 100 %
measured devices in their measuring
quantity for other circuits: 20 %
than rectifier
b Peak factor Instruments having electronic 100 %
instruments
devices in their measuring
circuits: 1 to 3
Frequency of AC measured quantity Reference frequency ± 10 % or 100 %
lower limit of reference range for
frequency - 10 % and upper limit
of reference range for frequency
+ 10 %
Magnetic field of Class indices 0,3 Class indices 0,5
0,4 kA/m
external origin and smaller and greater
Moving magnet, moving iron and 3 % of the fiducial 6 % of the fiducial
d d
electrodynamic instruments if not value value
astatic and/or not having a
magnetic screen
Ferrodynamic instruments if not 1,5 % of the fiducial 3 % of the fiducial
d d
astatic and/or not having a value value
magnetic screen
All other instruments 0,75 % of the 1,5 % of the fiducial
d d
fiducial value value

For an RMS-responding instrument which also responds to DC, no permissible variation can be stated because

the ripple is then part of the measured quantity.

For AC quantities, the requirements for instruments relate to RMS values irrespective of the principle of

operation of the instrument. However, instruments incorporating rectifier(s) (except r.m.s.-responding

instruments) usually respond to the rectified (mean) value of the waveform but are scaled to indicate theRMS

value of a sinusoidal waveform .If the waveform is not sinusoidal, the indicated value may be seriously in

uncertainty. However, if the waveform can be adequately characterized, this uncertainty is calculable.

Requirements for the influence of a distorted waveform on rectified (mean) and peak-sensing instruments are

therefore not specified.

The permissible variation due to a peak factor of other than √2 (corresponding to a sine wave) is included in

the permissible variation due to distortion of the measured quantity.

For instruments having a peak factor capability greater than 3, the manufacturer shall state:

1) the instrument peak factor capability producing a variation of 100 % of the class index;

2) the upper and lower limits of the frequency response (bandwidth) to 0,707 times the indication at the

reference frequency;

3) the effective maximum rate of change of internal instrument AC amplifier response (slew rate), expressed

in volts per second using appropriate SI prefixes.

Peak factor relates to the total peak factor capability of the instrument and includes both the peak factor due

to a distorted waveform and the peak factor due to spurious impulses (which may be random or harmonically

related to the fundamental frequency) containing negligible average power.
Not as a percentage of the class index.
---------------------- Page: 11 ----------------------
– 10 – IEC 60051-2:2018 © IEC 2018
5.3.2 Limits of variations
See IEC 60051-1:2016.
5.3.3 Conditions for the determination of variations
See IEC 60051-1:2016.
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.

For a fixed ammeter having the upper limit of its measuring range of 1 A to 10 A and intended

for use with a current transformer having a high over-current capability (Class P protective

current transformers as specified in IEC 61869-2), the measuring circuit shall not open when

the ammeter is subjected to 30 times the nominal secondary current of the associated current

transformer for a period of 2 s.

A portable ammeter intended for similar use shall withstand 15 times the upper limit of its

measuring range for a period of 2 s.

These ammeters need not be functional after application of this overload but shall not then be

open-circuit.
For the recommended test, see IEC 60051-9.
5.5.2 Self-heating
See IEC 60051-1:2016.
5.5.3 Permissible overloads
5.5.3.1 Continuous overload

Ammeters and voltmeters, together with their non-interchangeable accessory(ies), if any,

except for instruments fitted with a non-locking switch, shall be subjected to a continuous

overload of 120 % of the upper limit of the electrical input quantity for a period of 2 h. The

upper limit of the electrical input quantity of an ammeter with overload scale is the upper limit

of the non-overload part. The upper limit of the electrical input quantity of an expanded scale

voltmeter is the upper limit of the expanded part.

After removal of the excitation, the sum of the temporary and any permanent residual

deflections shall not exceed 1 % of the scale length.

After having cooled to the reference temperature, the instrument, together with its non-inter-

changeable accessory(ies), if any, shall comply with its accuracy requirements; however the

overload shall not be repeated.
The continuous overload test shall be carried out under reference conditions.
recommended test, see IEC 60051-9.
For the
----
...

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