Electricity metering equipment (AC) - Part 3: Particular requirements - Static meters for active energy (class indexes A, B and C)

Wechselstrom-Elektrizitätszähler - Teil 3: Besondere Anforderungen - Elektronische Wirkverbrauchszähler der Genauigkeitsklassen A, B und C

Équipement de comptage de l’électricité (c.a.) - Partie 3: Exigences particulières - Compteurs statiques d’énergie active (indices de classe A, B et C)

Oprema za merjenje električne energije (a.c.) - 3. del: Posebne zahteve - Statični števci za delovno energijo (razredni indeksi A, B in C)

General Information

Status
Not Published
Current Stage
4020 - Enquiry circulated
Due Date
07-May-2021
Completion Date
07-May-2021

RELATIONS

Buy Standard

Draft
prEN 50470-3:2021
English language
29 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 50470-3:2021
01-julij-2021

Oprema za merjenje električne energije (a.c.) - 3. del: Posebne zahteve - Statični

števci za delovno energijo (razredni indeksi A, B in C)

Electricity metering equipment (AC) - Part 3: Particular requirements - Static meters for

active energy (class indexes A, B and C)

Wechselstrom-Elektrizitätszähler - Teil 3: Besondere Anforderungen - Elektronische

Wirkverbrauchszähler der Genauigkeitsklassen A, B und C

Équipement de comptage de l’électricité (c.a.) - Partie 3: Exigences particulières -

Compteurs statiques d’énergie active (indices de classe A, B et C)
Ta slovenski standard je istoveten z: prEN 50470-3
ICS:
17.220.20 Merjenje električnih in Measurement of electrical
magnetnih veličin and magnetic quantities
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
oSIST prEN 50470-3:2021 en,fr

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

---------------------- Page: 1 ----------------------
oSIST prEN 50470-3:2021
---------------------- Page: 2 ----------------------
oSIST prEN 50470-3:2021
EUROPEAN STANDARD DRAFT
prEN 50470-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2021
ICS 91.140.50 Will supersede EN 50470-3:2006 and all of its
amendments and corrigenda (if any)
English Version
Electricity metering equipment (AC) - Part 3: Particular
requirements - Static meters for active energy (class indexes A,
B and C)

Équipement de comptage de l'électricité (c.a.) - Partie 3: Wechselstrom-Elektrizitätszähler - Teil 3: Besondere

Exigences particulières - Compteurs statiques d'énergie Anforderungen - Elektronische Wirkverbrauchszähler der

active (indices de classe A, B et C) Genauigkeitsklassen A, B und C
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2021-07-30.
It has been drawn up by CLC/TC 13.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CENELEC 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the

Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to

provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and

shall not be referred to as a European Standard.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Project: 65802 Ref. No. prEN 50470-3 E
---------------------- Page: 3 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
Contents Page

European foreword .................................................................................................................................... 4

1 Scope ............................................................................................................................................. 5

2 Normative references ................................................................................................................... 6

3 Terms and definitions .................................................................................................................. 6

4 Standard electrical values ........................................................................................................... 7

4.1 Voltages ......................................................................................................................................... 7

4.2 Currents ......................................................................................................................................... 7

4.2.1 General ........................................................................................................................................... 7

4.2.2 Nominal current ............................................................................................................................ 8

4.2.3 Starting current ............................................................................................................................. 8

4.2.4 Minimum current ........................................................................................................................... 8

4.2.5 Maximum current .......................................................................................................................... 8

4.3 Frequencies ................................................................................................................................... 8

4.4 Power consumption ..................................................................................................................... 8

5 Construction requirements .......................................................................................................... 8

6 Meter marking and documentation ............................................................................................. 9

7 Accuracy requirements ................................................................................................................ 9

7.1 General test conditions ................................................................................................................ 9

7.2 Methods of accuracy verification ................................................................................................ 9

7.3 Measurement uncertainty ............................................................................................................ 9

7.4 Meter constant .............................................................................................................................. 9

7.5 Initial start-up of the meter .......................................................................................................... 9

7.6 Test of no-load condition ............................................................................................................. 9

7.7 Starting current test ...................................................................................................................10

7.8 Repeatability test ........................................................................................................................10

7.9 Allowable errors due to variation of the current .....................................................................10

7.10 Allowable errors due to influence quantities and disturbances ............................................10

7.11 Time-keeping accuracy ..............................................................................................................15

7.12 Accuracy tests at reference conditions ...................................................................................15

7.13 Error of measurement ................................................................................................................16

8 Climatic conditions .....................................................................................................................17

8.1 General .........................................................................................................................................17

8.2 Test of the effect of the climatic environments .......................................................................17

9 The effects of external influences .............................................................................................17

10 Requirements concerning the software and protection against corruption ........................18

10.1 General .........................................................................................................................................18

10.2 Identification of functions implemented in software ..............................................................18

10.3 Identification and protection of software .................................................................................18

10.4 Identification and protection of metrologically relevant parameters ....................................18

10.5 Setting of parameters .................................................................................................................19

10.6 Protection of measurement data ...............................................................................................19

10.7 Protection against influence by metrologically non-relevant software ................................19

10.8 Protection against influence by connecting another device .................................................19

11 Type test ......................................................................................................................................19

12 Durability .....................................................................................................................................19

13 Reliability .....................................................................................................................................20

Annex A (informative) Calculation of the error of measurement .......................................................21

Annex B (informative) Differences between IEC and directive 2014/32/EU ......................................22

---------------------- Page: 4 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)

Annex C (informative) Accuracy classes ............................................................................................. 25

C.1 General ........................................................................................................................................ 25

C.2 Accuracy classes ....................................................................................................................... 25

Annex ZZ (informative) Relationship between this European Standard and the essential

requirements of Directive 2014/32/EU aimed to be covered .................................................. 26

Bibliography ............................................................................................................................................. 29

---------------------- Page: 5 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
European foreword

This document (prEN 50470-3:2021) has been prepared by CLC/TC 13 “Electrical energy measurement and

control”.
This document is currently submitted to the Enquiry.
The following dates are proposed:
• latest date by which the existence of this (doa) dor + 6 months
document has to be announced at national
level
• latest date by which this document has to be (dop) dor + 12 months
implemented at national level by publication of
an identical national standard or by
endorsement
• latest date by which the national standards (dow) dor + 36 months
conflicting with this document have to be (to be confirmed or
withdrawn modified when voting)

This document will supersede EN 50470-3:2006 and all of its amendments and corrigenda.

prEN 50470-3:2021 includes the following significant technical changes with respect to EN 50470-3:2006: it is

based on EN IEC 62052-11:2021 instead of EN 50470-1:2006.

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

European Free Trade Association, and supports essential requirements of EU Directive(s).

For the relationship with EU Directive(s) see informative Annex ZZ, which is an integral part of this document.

prEN 50470-3:2021 is related to:

— EN IEC 62053-21:2021, Electricity metering equipment – Particular requirements – Part 21: Static meters

for AC active energy (classes 0,5, 1 and 2)

— EN IEC 62053-22:2021, Electricity metering equipment – Particular requirements – Part 22: Static meters

for AC active energy (classes 0,1 S, 0,2 S and 0,5 S).

NOTE Terms differences for accuracy classes and current values in related standards (EN IEC 62053-21:2021 and

EN IEC 62053-22:2021) and directive 2014/32/EU are listed in Annex C.

The structure of the standards is similar; modifications in this document are provided in the perspective of

compliance with the Essential Requirements of Directive 2014/32/EU on Measuring Instruments (MID).

---------------------- Page: 6 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
1 Scope

This document applies only to static watt-hour meters of accuracy classes A, B and C for the measurement of

alternating current electrical active energy in 50 Hz or 60 Hz networks and it applies to their type tests only.

NOTE 1 For general requirements, such as construction, EMC, safety, dependability etc., see the relevant EN 62052

series or EN 62059 series.
This document applies to electricity metering equipment designed to:

— measure and control electrical energy on electrical networks (mains) with voltage up to 1 000 V AC;

NOTE 2 For AC electricity meters, the voltage mentioned above is the line-to-neutral voltage derived from nominal

voltages. See EN 62052-31:2016, Table 7.

— have all functional elements, including add-on modules, enclosed in, or forming a single meter case with

exception of indicating displays;
— operate with integrated or detached indicating displays;
— be installed in a specified matching sockets or racks;

— optionally, provide additional functions other than those for measurement of electrical energy.

Meters designed for operation with low power instrument transformers (LPITs as defined in the IEC 61869

series) can be tested for compliance with this document only if such meters and their LPITs are tested together

and meet the requirements for directly connected meters.

NOTE 3 Modern electricity meters typically contain additional functions such as measurement of voltage magnitude,

current magnitude, power, frequency, power factor, etc.; measurement of power quality parameters; load control functions;

delivery, time, test, accounting, recording functions; data communication interfaces and associated data security functions.

The relevant standards for these functions could apply in addition to the requirements of this document. However, the

requirements for such functions are outside the scope of this document.

NOTE 4 Product requirements for power metering and monitoring devices (PMDs) and measurement functions such as

voltage magnitude, current magnitude, power, frequency, etc., are covered in EN 61557-12. However, devices compliant

with EN 61557-12 are not intended to be used as billing meters unless they are also compliant with the

EN IEC 62052-11:2021 and prEN 50470-3:2021 standards.

NOTE 5 Product requirements for power quality instruments (PQIs) are covered in EN 62586-1. Requirements for power

quality measurement techniques (functions) are covered in EN 61000-4-30. Requirements for testing of the power quality

measurement functions are covered in EN 62586-2.
This document does not apply to:

— meters for which the voltage line-to-neutral derived from nominal voltages exceeds 1 000 V AC;

— meters intended for connection with low power instrument transformers (LPITs as defined in the EN 61869

series) when tested without such transformers;

— metering systems comprising multiple devices (except of LPITs) physically remote from one another;

— portable meters;
NOTE 6 Portable meters are meters that are not permanently connected.
— meters used in rolling stock, vehicles, ships and airplanes;
— laboratory and meter test equipment;
---------------------- Page: 7 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
— reference standard meters;
— data interfaces to the register of the meter;

— matching sockets or racks used for installation of electricity metering equipment;

— any additional functions provided in electrical energy meters.

This document does not cover measures for the detection and prevention of fraudulent attempts to compromise

meter’s performance (tampering).

NOTE 7 Nevertheless, specific tampering detection and prevention requirements, and test methods, as relevant for a

particular market are subject to the agreement between the manufacturer and the purchaser.

NOTE 8 Specifying requirements and test methods for fraud detection and prevention would be counterproductive, as

such specifications would provide guidance for potential fraudsters.

NOTE 9 There are many types of meter tampering reported from various markets; therefore, designing meters to detect

and prevent all types of tampering could lead to unjustified increase in costs of meter design, verification and validation.

NOTE 10 Billing systems, such as, smart metering systems, are capable of detecting irregular consumption patterns and

irregular network losses which enable discovery of suspected meter tampering.

NOTE 11 For transformer operated meters paired with current transformers (CTs) according EN 61869-2: the standard

CT measuring range is specified from 0,05 I to I for accuracy classes 0,1, 0,2, 0,5 and 1 and these CTs are used for

n max
meters of class C, B and A according to this document.

NOTE 12 This document does not specify emission requirements, these are specified in EN IEC 62052-11:2021, 9.3.14.

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.

EN IEC 62052-11:2021, Electricity metering equipment – General requirements, tests and test conditions - Part

11: Metering equipment (IEC 62052-11:2020)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in EN IEC 62052-11:2021 and the following

apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/

NOTE The definitions listed here take precedence over those in EN IEC 62052-11:2021.

3.1
transitional current

value of the current at, and above which, up to I full accuracy requirements of this document apply

max
3.2
influence quantity
quantity that is not the measurand but that affects the result of measurement
---------------------- Page: 8 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
3.3
disturbance

influence quantity having a value within the limits specified in the appropriate requirement but outside the

specified rated operating conditions of the measuring instrument

Note 1 to entry: An influence quantity is a disturbance if for that influence quantity the rated operating conditions are not

specified.
3.4
critical change value
value at which the change in the measurement result is considered undesirable

Note 1 to entry: The critical change value specifies here the maximum change in the measurement results for all

disturbances. In EN IEC 62052-11:2021, the critical change value has another definition and meaning and applies only for

tests without any current.
3.5
rated operating condition

value for the measurand and influence quantities making up the normal working conditions of an instrument

3.6
maximum permissible error
MPE

maximum allowable error under rated operating conditions and in the absence of a disturbance

4 Standard electrical values
4.1 Voltages
The values in EN IEC 62052-11:2021, 4.1 apply.
4.2 Currents
4.2.1 General
Table 1 — Preferred values of I and I
tr n
Meters for Current Value of current
I 0,1–0,2–0,5–1-1,5–2-3–4-5–
6,3–8-10–12,5
Direct connection
I 1–2-5–10–15–20–30–40–50–
63–80–100–125
I 0,05–0,1–0,25
Transformer operated
I 1–2-5

For meters intended for operation with LPITs, the values in Table 1 for direct connection apply to the primary

ratings of the LPITs used with the meter.
NOTE 1 The values for I are from EN IEC 62052-11:2021, Table 3.

NOTE 2 Meters operating with external LPITs are sometimes specified for nominal current values greater than the values

in Table 1, e.g. common values to be considered are 160A, 200A, 250A, 400A, 500A, 600A, 630A.

---------------------- Page: 9 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
4.2.2 Nominal current
The nominal current I for direct connected meters shall be 10 I .
n tr
The nominal current I for transformer operated meters shall be 20 I .
n tr
4.2.3 Starting current
Starting current relation to I is shown in Table 2 below.
Table 2 — Starting current
Meters for Meters of class index Power
factor
A B C
Direct connection ≤ 0,05 I ≤ 0,04 I ≤ 0,04 I 1
tr tr tr
Transformer operated ≤ 0,06 I ≤ 0,04 I ≤ 0,02 I 1
tr tr tr
4.2.4 Minimum current
Starting current relation to I is shown in Table 3 below.
min
Table 3 — Minimum current
Meters for Minimum current I
min
Class A Class B Class C
Direct connection ≤ 0,5 I ≤ 0,5 I ≤ 0,3 I
tr tr tr
Transformer operated ≤ 0,4 I ≤ 0,2 I ≤ 0,2 I
tr tr tr
4.2.5 Maximum current
Starting current relation to I is shown in Table 4 below.
max
Table 4 — Maximum current
Meters for Maximum current I
max
Class A Class B Class C
Direct connection ≥ 50 I ≥ 50 I ≥ 50 I
tr tr tr
Transformer operated ≥ 24 I ≥ 24 I ≥ 24 I
tr tr tr
4.3 Frequencies
The values given in EN IEC 62052-11:2021, 4.3 apply.
4.4 Power consumption
The values given in EN IEC 62052-11:2021, 4.4 apply.
5 Construction requirements
The requirements given in EN IEC 62052-11:2021, Clause 5 apply.
---------------------- Page: 10 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)

In addition to the requirements in EN IEC 62052-11:2021, 5.6, these requirements apply:

a) The scale interval for a measured value shall be in the form 1x10n, 2x10n, or 5x10n, where n is any integer

or zero. The unit of measurement or its symbol shall be shown close to the numerical value.

b) The indication of any result shall be clear and unambiguous and accompanied by such marks and

inscriptions necessary to inform the user of the significance of the result. Easy reading of the presented

result shall be permitted under normal conditions of use. Additional indications may be shown provided

they cannot be confused with the metrologically controlled indications.

NOTE 1 Metrologically relevant information on the display requires an unambiguous identification of the way it is defined.

The user manual could provide additional details.

NOTE 2 The mechanical tests specified in EN IEC 62052-11:2021 are deemed to provide evidence for compliance with

the M1 and M2 requirements, if the meter after the tests shows no damage or change of the information and operates

correctly in accordance with the requirements of EN IEC 62052-11:2021. As static meters have no moving parts, it is

sufficient to perform metrological tests after the mechanical tests only.

NOTE 3 In contrast to EN IEC 62052-11:2021, 5.6.2 (Meters without indicating displays), meters without indicating

display are not permitted under 2014/32/EU.
6 Meter marking and documentation

The requirements of EN IEC 62052-11:2021, Clause 6 apply together with those listed here.

The current measuring range shall be marked as follows:

— for direct connected meters, the minimum current (I ), nominal current (I ), and maximum current (I ),

min n max
for example, 0,5-10(80) A;

— the rated secondary current of transformer(s) to which a transformer-operated meter should be connected,

for example: /5 A or /1 A. The nominal current(s) and the maximum current(s) of the meter may be included

in the type designation.
7 Accuracy requirements
7.1 General test conditions
Tests and test conditions given in EN IEC 62052-11:2021, 7.1 apply.
7.2 Methods of accuracy verification
Tests and test conditions given in EN IEC 62052-11:2021, 7.2 apply.
7.3 Measurement uncertainty

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.3 apply.

7.4 Meter constant

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.4 apply.

7.5 Initial start-up of the meter

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.5 apply.

7.6 Test of no-load condition

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.6 apply.

In addition to the test at 1,1 U , the test shall be executed at 0,8 U .
n n
---------------------- Page: 11 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)
7.7 Starting current test

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.7 apply.

7.8 Repeatability test

The requirements, test conditions and procedures, and acceptance criteria of EN IEC 62052-11:2021, 7.8 apply.

NOTE The result of a reproducibility assessment according to the Directive 2014/32/EU is not expected to be

significantly different than for the repeatability test for static electricity meters.

7.9 Allowable errors due to variation of the current

When the meter is operated under reference conditions as specified in 7.1 of EN IEC 62052-11:2021, Table 10,

and the current and the power factor are varied, the percentage errors shall not exceed the limits specified for

the relevant class indexes in Table 5.

If the meter is designed for the measurement of energy in both directions, the values in Table 5 shall apply for

each direction.

If the meter is rated for multiple connection modes, the accuracy testing results are valid only for the connection

modes tested and cannot be used to claim accuracy for other untested connection modes.

Table 5 — Acceptable percentage error limits at reference conditions

(single-phase meters and poly-phase meters with balanced loads or single-phase loads)

Value of current Acceptable percentage error limits
for direct connected or for meters of class index
Power factor
transformer operated meters
A B C
I ≤ I < I 1 ± 2,5 ± 1,5 ± 1,0
min tr
I ≤ I ≤ I 0,5 ind…1…cap 0,8 ± 2,0 ± 1,0 ± 0,5
tr max

Additionally, for currents outside of the controlled current range (i.e. between I and I ), unduly biasing

min max

shall not occur. The percentage errors shall not exceed the limits specified for the relevant class indexes in

Table 6.
Table 6 — Acceptable percentage error limits at reference conditions

(single-phase meters and poly-phase meters with balanced loads or single-phase loads)

Value of current Acceptable percentage error limits
Power
for direct connected or for meters of class index
factor
transformer operated meters
A B C
I ≤ I < I 1 ± 2,5· I /I ± 1,5· I /I ± 1,0· I /I
st min min min min
NOTE 1 The limits between I ≤ I < I are from OIML R46-1/-2: 2012, section 3.3.3.
st min

NOTE 2 Values above I are not expected to occur in installations for longer durations normally (i.e. more than a few

max

hours in a year). However, error limits above I can be specified in an agreement between the manufacturer and the

max
purchaser or according to national regulatory requirements.

NOTE 3 Alternative approaches could be acceptable to demonstrate the requirement of no unduly biasing. The

specifications provided in this document represent the view of TC 13, WG 01 as the best practice to be followed.

7.10 Allowable errors due to influence quantities and disturbances

Reference conditions as specified in 7.1 of EN IEC 62052-11:2021, Table 10 apply.

---------------------- Page: 12 ----------------------
oSIST prEN 50470-3:2021
prEN 50470-3:2021 (E)

NOTE Differences exist between terminologies in IEC standards and directive 2014/32/EU. They are detailed in Table

B.1 of Annex B.

If the meter is rated for multiple connection modes, the accuracy requirements apply for each of the connection

modes. All tests of effects of influence quantities shall be performed in one connection mode selected to exercise

the complete metrological capability of the meter.

When the current and the phase displacement (power factor) are held constant as specified in 7.1 of

EN IEC 62052-11:2021, Table 10, and any single influence quantity is applied one at a time, with the meter

otherwise operated at reference conditions as specified in 7.1 of EN IEC 62052-11:2021, Table 10, the variation

in percentage error relative to the intrinsic error shall not exceed the limits specified for the relevant class indexes

given in Table 7 and Table 8.
The variation in percentage error due to temperature variatio
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.