Direct acting indicating analogue electrical measuring instruments and their accessories - Part 5: Special requirements for phase meters, power factor meters and synchroscopes

IEC 60051-5:2017 applies to direct acting indicating phase meters, power factor meters and synchroscopes having an analogue display.
This document also applies to non-interchangeable accessories (as defined in 3.1.23 of IEC 60051-1:2016) used with phase meters, power factor meters and synchroscopes.
This document also applies to a phase meter or power factor meter whose scale marks do not correspond directly to its electrical input quantity, provided that the relationship between them is known.
This fifth edition cancels and replaces the fourth edition published in 1985. 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 5: Exigences particulières pour les phasemètres, les appareils de mesure de facteur de puissance et les synchronoscopes

L'IEC 60051-5:2017 s'applique aux phasemètres, aux appareils de mesure de facteur de puissance et aux synchronoscopes indicateurs analogiques à action directe.
Le présent document s'applique également aux accessoires non interchangeables (définis en 3.1.23 de l'IEC 60051-1:2016) utilisés avec les phasemètres, les appareils de mesure de facteur de puissance et les synchronoscopes.
Le présent document s'applique également aux phasemètres ou aux appareils de mesure de facteur de puissance dont les repères d'échelle ne correspondent pas directement à la grandeur électrique appliquée à l'entrée de l'appareil, à condition que la relation entre celles-ci soit connue.
Cette cinquième édition annule et remplace la quatrième édition parue en 1985. 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 60051-5
Edition 5.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 5: Special requirements for phase meters, power factor meters and
synchroscopes
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 5: Exigences particulières pour les phasemètres, les appareils de mesure
de facteur de puissance et les synchronoscopes
IEC 60051-5:2017-12(en-fr)
---------------------- Page: 1 ----------------------
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---------------------- Page: 2 ----------------------
IEC 60051-5
Edition 5.0 2017-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Direct acting indicating analogue electrical measuring instruments and their
accessories –
Part 5: Special requirements for phase meters, power factor meters and
synchroscopes
Appareils mesureurs électriques indicateurs analogiques à action directe et
leurs accessoires –
Partie 5: Exigences particulières pour les phasemètres, les appareils de mesure
de facteur de puissance et les synchronoscopes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.220.20 ISBN 978-2-8322-5187-4

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 60051-5:2017 © 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........................................................................................... 9

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 ........................................................................ 11

5.5.5 Deviation from zero ....................................................................................... 11

5.5.6 Electromagnetic compatibility (EMC) ............................................................. 11

5.5.7 Special requirements for synchroscopes ........................................................ 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 .............................................................................. 12

5.6.4 Scales ........................................................................................................... 12

5.6.5 Stopper.......................................................................................................... 12

5.6.6 Preferred values ............................................................................................ 12

5.6.7 Adjusters, mechanical and/or electrical .......................................................... 13

5.6.8 Effects of vibration and shock ........................................................................ 13

5.6.9 Degrees of protection provided by enclosure ................................................. 13

5.6.10 Terminals ...................................................................................................... 13

6 Information, markings and symbols ................................................................................ 13

6.1 Information ........................................................................................................... 13

6.2 Markings, symbols and their locations ................................................................... 13

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

influence quantities ............................................................................................... 13

6.4 The symbols for marking instruments and accessories .......................................... 13

6.5 Markings and symbols for terminals ...................................................................... 13

---------------------- Page: 4 ----------------------
IEC 60051-5:2017 © IEC 2017 – 3 –

6.5.1 Requirements for markings ............................................................................ 13

6.5.2 Earthing (grounding) terminals ....................................................................... 13

6.5.3 Measuring circuit terminals ............................................................................ 14

6.5.4 Special markings for terminals ....................................................................... 14

6.6 Instructions for use ............................................................................................... 14

7 Package ........................................................................................................................ 14

8 Test rules ...................................................................................................................... 14

Annex A (normative) Nonconformity classification of tests ................................................... 15

Bibliography .......................................................................................................................... 16

Table 1 – Reference conditions and tolerances, additional to those given in Table 2 of

IEC 60051-1:2016, for testing purposes relating to the influence quantities ............................. 8

Table 2 – 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 3 – Overloads of short duration ................................................................................... 11

Table A.1 – Nonconformity classification of tests .................................................................. 15

---------------------- Page: 5 ----------------------
– 4 – IEC 60051-5:2017 © IEC 2017
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 5: Special requirements for phase meters,
power factor meters and synchroscopes
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

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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 60051-5 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 1985. 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 60051-5:2017 © IEC 2017 – 5 –
The text of this International Standard is based on the following documents:
CDV Report on voting
85/581/CDV 85/581A/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 60051-5:2017 © 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 60051-5 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 60051-5:2017 © IEC 2017 – 7 –
DIRECT ACTING INDICATING ANALOGUE ELECTRICAL
MEASURING INSTRUMENTS AND THEIR ACCESSORIES –
Part 5: Special requirements for phase meters,
power factor meters and synchroscopes
1 Scope

This part of IEC 60051 applies to direct acting indicating phase meters, power factor meters

and synchroscopes having an analogue display.

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

IEC 60051-1:2016) used with phase meters, power factor meters and synchroscopes.

This document also applies to a phase meter or power factor meter whose scale marks do not

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

is known.
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

Phase meters, power factor meters and synchroscopes shall be classified in one of the

accuracy classes denoted by the following class indices:
0,1, 0,2, 0,3, 0,5, 1, 1,5, 2, 2,5, 3, 5
4.3 Compliance with the requirements of this standard
See IEC 60051-1:2016.
---------------------- Page: 9 ----------------------
– 8 – IEC 60051-5:2017 © IEC 2017
5 Requirements
5.1 Reference conditions

See IEC 60051-1:2016. The reference value of the influence quantities should be as given in

Table 2 of IEC 60051-1:2016 and Table 1.

Table 1 – Reference conditions and tolerances, additional to those given in Table 2

of IEC 60051-1:2016, for testing purposes relating to the influence quantities

Influence quantity Reference conditions unless otherwise marked Tolerance permitted for

testing purposes,
applicable for a single
reference value

Voltage component of the Rated voltage or any voltage within the reference range ±2 % of the rated value

measured quantity
Current component of the 40 % ... 100 % of rated current –
measured quantity

Frequency of voltage and Instruments using phase Reference frequency ±0,1 % of the reference

current components of the shifting devices frequency
measured quantity
Other instruments 45 Hz to 65 Hz ±2 % of the reference
frequency
Phase balance (for Symmetrical voltages and currents
polyphase instruments)

This tolerance applies when a single reference value is specified in this table or is marked by the

manufacturer. For a reference range, no tolerance is allowed.

Each of the voltages (between any two lines or between line and neutral) should not differ by more than 1 %

from the average of the voltages (line-to-line or line-to-neutral) of the system.

Each of the currents in the phases should not differ by more than 1 % from the average of the currents.

The angles between each of the currents and the corresponding phase-to-neutral voltages should not differ by

more than 2° from the average of the angles.
5.2 Limits of intrinsic uncertainty, fiducial value
5.2.1 Limits of intrinsic uncertainty
See IEC 60051-1:2016.

For a synchroscope, the accuracy requirements apply only at the synchronizing mark.

5.2.2 Correspondence between intrinsic uncertainty and accuracy class
See IEC 60051-1:2016.
5.2.3 Fiducial value
The fiducial value corresponds to a phase angle of 90°.

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).
5.3 Nominal range of use and variations
5.3.1 Nominal range of use

See IEC 60051-1:2016. The limits of the nominal range of use for influence quantities shall be

as given in Table 3 of IEC 60051-1:2016 and Table 2.
---------------------- Page: 10 ----------------------
IEC 60051-5:2017 © IEC 2017 – 9 –
Table 2 – 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 the nominal range of Permissible variation expressed

use unless otherwise marked
Distortion of Distortion factor 5 % 100 %
voltage and/or
a b
Peak factor 1 to 3 Under consideration
current
components of the
measured quantity
Frequency of Instruments using Reference frequency ±1 % or lower 100 %
voltage and phase shifting limit of reference range -1 % and
current devices upper limit of reference range +1 %
components of the
Other instruments Reference frequency ±10 % or
measured quantity
lower limit of reference range -10 %
and upper limit of reference range
+10 %
Voltage components of the measured Reference voltage ±15 % or lower 100 %
quantity limit of reference range -15 % and
upper limit of reference range
+15 %
20 %...120 % of rated current 100 %
Current components of the measured
quantity
Phase balance (for polyphase Disconnection of one current 200 %
instruments) component of the measured quantity
Magnetic field of external origin 0,4 kA/m Class Class
indices indices
0,3 and 0,5 and
smaller greater
Electro- 3 % of the 6 % of the
dynamic fiducial fiducial
c c
instruments values values
if not static
and/or not
having a
magnetic
screen
Ferro- 1,5 % of the 3 % of the
dynamic fiducial fiducial
c c
instruments values values
if not static
and/or not
having a
magnetic
screen
All other 0,75 % of 1,5 % of the
instruments the fiducial fiducial
c c
values values
For instruments having electronic devices in their measuring circuits.

The permissible variation due to a peak factor of other than (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:

The peak factor producing a variation of 100 % of the class index.

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

reference frequency.

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

in volts per second, using appropriate SI prefixes.
Not as a percentage of the class index.
5.3.2 Limits of variations
See IEC 60051-1:2016 and Table 2.
---------------------- Page: 11 ----------------------
– 10 – IEC 60051-5:2017 © IEC 2017
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.
5.5.2 Self-heating
See IEC 60051-1:2016.
However, the requirements of IEC 60051-1:2016 do not apply to synchroscopes.
5.5.3 Permissible overloads
5.5.3.1 Continuous overload
For the recommended test, see IEC 60051-9.

All phase meters and power factor meters, 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 rated value for all current circuits

simultaneously for a period of 2 h.

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 but without

repeating the overload.

The continuous overload test shall be carried out under reference conditions except for

current.
The requirements for continuous overload do not apply to synchroscopes.
5.5.3.2 Overloads of short duration
5.5.3.2.1 For the recommended test, see IEC 60051-9.

All phase meters, power factor meters and synchroscopes, together with their non-

interchangeable accessory(ies), if any, shall be subjected to overloads of short duration.

However, these requirements do not apply to instruments whose scale marks do not

correspond directly to their electrical input quantities (but not excluding instruments intended

to be used with (an) instrument transformer(s)).

5.5.3.2.2 The values of current and voltage for the overloads of short duration shall be the

product of the relevant factor given in Table 3 and the rated value of voltage or the upper limit

of the nominal range of use for current unless other values are stated by the manufacturer.

The overloads shall be applied separately to each input circuit.
---------------------- Page: 12 ----------------------
IEC 60051-5:2017 © IEC 2017 – 11 –
Table 3 – Overloads of short duration
Measuring circuit Overload factor Number of Duration of each Interval between
overloads overload successive
overloads
(s) (s)
Class indices 0,5 and smaller
Current circuit 2
5 1 15
Voltage circ
...

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