EN 50470-2:2006

SLOVENSKI STANDARD
01-marec-2007
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Electricity metering equipment (a.c.) -- Part 2: Particular requirements -
Electromechanical meters for active energy (class indexes A and B)
Wechselstrom-Elektrizitätszähler -- Teil 2: Besondere Anforderungen -
Elektromechanische Wirkverbrauchszähler der Genauigkeitsklassen A und B
Equipement de comptage d'électricité (c.a.) -- Partie 2: Prescriptions particulières -
Compteurs électromécaniques d'énergie active (classes de précision A et B)
Ta slovenski standard je istoveten z: EN 50470-2:2006
ICS:
17.220.20 0HUMHQMHHOHNWULþQLKLQ Measurement of electrical
PDJQHWQLKYHOLþLQ and magnetic quantities
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 50470-2
NORME EUROPÉENNE
October 2006
EUROPÄISCHE NORM
ICS 91.140.50
English version
Electricity metering equipment (a.c.)
Part 2: Particular requirements -
Electromechanical meters for active energy
(class indexes A and B)
Equipement de comptage  Wechselstrom-Elektrizitätszähler
d'électricité (c.a.) Teil 2: Besondere Anforderungen -
Partie 2: Prescriptions particulières - Elektromechanische
Compteurs électromécaniques Wirkverbrauchszähler
d'énergie active der Genauigkeitsklassen A und B
(classes de précision A et B)
This European Standard was approved by CENELEC on 2006-05-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50470-2:2006 E
Foreword
This European Standard was prepared by the Technical Committee CENELEC TC 13, Equipment for
electrical energy measurement and load control.
The text of the draft was submitted to the Unique Acceptance Procedure and was approved by
CENELEC as EN 50470-2 on 2006-05-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2007-05-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2009-05-01
This EN 50470-2 is related to EN 62053-11:2003, Electricity metering equipment (a.c.) – Particular
requirements – Part 11: Electromechanical meters for active energy (classes 0,5, 1 and 2).
The structure of the two standards is similar, modifications in this European Standard are provided in
the perspective of compliance with the Essential Requirements of the Directive 2004/22/EC on
Measuring Instruments (MID).
This standard is to be used with EN 50470-1:2006, Electricity metering equipment (a.c.) – Part 1:
General requirements, tests and test conditions – Metering equipment (class indexes A, B and C).
This European Standard has been prepared under a mandate given to CENELEC by the European
Commission and the European Free Trade Association and covers essential requirements of
EC Directive 2004/22/EC. See Annex ZZ.
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– 3 – EN 50470-2:2006
Contents
1 Scope.5
2 Normative references .5
3 Terms, definitions and abbreviations .5
4 Standard electrical values .6
5 Mechanical requirements.6
5.1 General .6
5.2 Register (counting mechanism) .6
5.3 Direction of rotation and marking of the rotor.6
6 Climatic conditions .6
7 Electrical requirements .6
7.1 Power consumption .6
7.1.1 Measuring method .6
7.1.2 Voltage circuits.7
7.1.3 Current circuits .7
7.2 AC voltage test.7
8 Accuracy requirements and tests.9
8.1 Limits of percentage error due to variation of the load .9
8.2 Repeatability .9
8.3 Limits of additional percentage error due to influence quantities.9
8.4 Maximum permissible error (MPE).11
8.5 Effect of disturbances of long duration.11
8.6 Short time overcurrents .13
8.7 Performing the tests .13
8.7.1 Accuracy test conditions.13
8.7.2 Accuracy test at reference conditions .15
8.7.3 Interpretation of accuracy test results .15
8.7.4 Repeatability .15
8.7.5 Test of effects of influence quantities.15
8.7.6 Calculation of the composite error .16
8.7.7 Test of effects of disturbances of long duration.16
8.7.8 Short time overcurrents .19
8.7.9 Test of starting and no-load condition .19
8.7.10 Meter constant.20
8.7.11 Adjustment .20
9 Durability.21
10 Reliability .21
11 Protection against corruption .21
Annex A (informative) Calculation of the composite error .22
Annex B (normative) Test circuit diagram for the test of immunity to earth fault .23
Annex ZZ (informative) Coverage of Essential Requirements of EC Directives.24
Bibliography.25

Figures
Figure B.1 – Circuit to simulate earth fault condition in phase 1 .23
Figure B.2 – Voltages at the meter under test .23
Tables
Table 1 – Power consumption in voltage circuits .7
Table 2 – Power consumption in current circuits .7
Table 3 – AC voltage tests.8
Table 4 – Percentage error limits at reference conditions (single-phase meters and
polyphase meters with balanced loads) .9
Table 5 – Percentage error limits at reference conditions (polyphase meters carrying a
single-phase load, but with balanced polyphase voltages applied to voltage
circuits) .9
Table 6 – Limits of additional percentage error due to influence quantities (single-
phase meters and polyphase meters with balanced loads).10
Table 7 – Limits of additional percentage error due to influence quantities (polyphase
meters carrying a single phase load, but with balanced polyphase voltages
applied to voltage circuits).10
Table 8 – Maximum permissible error (MPE).11
Table 9 – Effect of disturbances of long duration – Critical change values .12
Table 10 – Effect of short time overcurrents – Critical change value .13
Table 11 – Voltage and current balance.13
Table 12 – Reference conditions.14
Table 13 – Test points for determining the intrinsic error and the additional percentage
error due to influence quantities .15
Table 14 – Interpretation of test results.15
Table 15 – Starting current .20
Table 16 – Minimum range of adjustment.20

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– 5 – EN 50470-2:2006
1 Scope
This European Standard applies to newly manufactured electromechanical watt-hour meters intended
for residential, commercial and light industrial use, of class indexes A and B, for the measurement of
alternating current electrical active energy in 50 Hz networks. It specifies particular requirements and
type test methods.
It applies to electromechanical watt-hour meters for indoor and outdoor application, consisting of a
measuring element and register(s) enclosed together in a meter case. It also applies to operation
indicator(s) and test output(s).
If the meter has (a) measuring element(s) for more than one type of energy (multi-energy meters), or
when other functional elements, like maximum demand indicators, electronic tariff registers, time
switches, ripple control receivers, data communication interfaces etc. are enclosed in the meter case
(multi-function meters) then this standard applies only for the active energy metering part.
This standard distinguishes between:
– meters of class indexes A and B;
– direct connected and transformer operated meters;
– meters for use in networks equipped with or without earth fault neutralizers.
It does not apply to:
– watt-hour meters where the voltage across the connection terminals exceeds 600 V (line-to-line
voltage for meters for polyphase systems);
– portable meters.
1)
Methods for acceptance testing are covered by the IEC 62058 series of standards .
The dependability aspect is covered by the documents of the IEC 62059 series.
2 Normative references
The following referenced documents are indispensable for the application 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.
Publication Year Title
EN 50470-1 2006 Electricity metering equipment (a.c.) – Part 1: General requirements, tests
and test conditions – Metering equipment (class indexes A, B and C)
3 Terms, definitions and abbreviations
For the purposes of this document, the terms and definitions given in EN 50470-1 apply.
———————
1)
At draft stage.
...