Electricity metering - Payment systems -- Part 31: Particular requirements - Static payment meters for active energy (classes 1 and 2)

This part of IEC 62055 applies to newly manufactured, static  watt-hour payment meters of accuracy classes 1 and 2 for  direct connection, for the measurement of alternating current  electrical energy consumption of a frequency in the range 45  Hz to 65 Hz that include a load switch for the purpose of  interruption or restoration of the electricity supply to the load in  accordance with the current value of the available credit  maintained in the payment meter. It does not apply to static  watt-hour payment meters where the voltage across the  connection terminals exceeds 600 V (line-to-line voltage for  meters for polyphase systems). It applies to payment meters  for indoor application only, where the payment meter shall be  mounted as for normal service (i.e. together with a specified  matching socket where applicable). Payment meters are  implementations where all the main functional elements are  incorporated in a single enclosure, together with any specified  matching socket. There are also multi-part installations where  the various main functional elements, such as the measuring  element, the user interface unit, token carrier interface, and  the load switch are implemented in more than one enclosure,  involving additional interfaces. This part of IEC 62055 does not  apply to multipart payment metering installations. Functional  requirements that apply to payment meters are also defined in  this part of IEC 62055, and include informative basic functional  requirements and tests for the prepayment mode of operation  in Annex A. Allowances are made for the relatively wide range  of features, options, alternatives, and implementations that  may be found in practice. The diverse nature and functionality  of payment meters prevent the comprehensive specification of  detailed test methods for all of these requirements. However,  in this case, the requirements are stated in such a way that  tests can then be formulated to respect and validate the  specific functionality of the payment meter being tested. This  part of IEC 62055 does not cover specific functionality or  performance requirements for safety, circuit protection,  isolation or similar purposes that may be specified through  reference to other specifications or standards. This part of IEC  62055 does not cover software requirements. Software  requirements for basic energy meter metrology are under  consideration for the IEC 62059 series of standards, and in  other organisations. This part of IEC 62055 covers type-testing  requirements only. For acceptance testing, the concepts given  in IEC 61358 may be used as a basic guideline. Dependability  aspects are addressed in the IEC 62059 series of standards.  This part of IEC 62055 does not cover conformity tests and  system compliance tests that may be required in connection  with legal or other requirements of some markets.

Messung der elektrischen Energie - Zählersysteme mit Inkassofunktion -- Teil 31: Besondere Anforderungen - Elektronische Inkasso-Wirkverbrauchszähler (Klassen 1 und 2)

Equipements de comptage de l'électricité - Systèmes à paiement -- Partie 31: Prescriptions particulières - Compteurs statiques à paiement d'énergie active (classes 1 et 2)

applies to newly manufactured, static watt-hour payment meters of accuracy classes 1 and 2 for direct connection, for the measurement of alternating current electrical energy consumption of a frequency in the range 45 Hz to 65 Hz that include a load switch for the purpose of interruption or restoration of the electricity supply to the load in accordance with the current value of the available credit maintained in the payment meter. It does not apply to static watt-hour payment meters where the voltage across the connection terminals exceeds 600 V (line-to-line voltage for meters for polyphase systems).

Merjenje električne energije - Plačilni sistemi - 31. del: Posebne zahteve - Statični plačilni števci za delovno energijo (razreda 1 in 2) (IEC 62055-31:2005)

General Information

Status
Published
Publication Date
28-Feb-2007
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Mar-2007
Due Date
01-Mar-2007
Completion Date
01-Mar-2007

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SLOVENSKI STANDARD
SIST EN 62055-31:2007
01-marec-2007

0HUMHQMHHOHNWULþQHHQHUJLMH3ODþLOQLVLVWHPLGHO3RVHEQH]DKWHYH6WDWLþQL

SODþLOQLãWHYFL]DGHORYQRHQHUJLMR UD]UHGDLQ  ,(&

Electricity metering - Payment systems -- Part 31: Particular requirements - Static

payment meters for active energy (classes 1 and 2)
Messung der elektrischen Energie - Zhlersysteme mit Inkassofunktion -- Teil 31:

Besondere Anforderungen - Elektronische Inkasso-Wirkverbrauchszhler (Klassen 1 und

Equipements de comptage de l'lectricit - Systmes paiement -- Partie 31: Prescriptions

particulires - Compteurs statiques paiement d'nergie active (classes 1 et 2)
Ta slovenski standard je istoveten z: EN 62055-31:2005
ICS:
91.140.50 Sistemi za oskrbo z elektriko Electricity supply systems
SIST EN 62055-31:2007 en

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

---------------------- Page: 1 ----------------------
EUROPEAN STANDARD EN 62055-31
NORME EUROPÉENNE
EUROPÄISCHE NORM December 2005
ICS 91.140.50
English version
Electricity metering –
Payment systems
Part 31: Particular requirements –
Static payment meters for active energy (classes 1 and 2)
(IEC 62055-31:2005)
Equipements de comptage de l'électricité - Messung der elektrischen Energie -
Systèmes à paiement Zählersysteme mit Inkassofunktion
Partie 31: Prescriptions particulières - Teil 31: Besondere Anforderungen -
Compteurs statiques à paiement d'énergie Elektronische Inkasso-
active (classes 1 et 2) Wirkverbrauchszähler (Klassen 1 und 2)
(CEI 62055-31:2005) (IEC 62055-31:2005)

This European Standard was approved by CENELEC on 2005-11-01. 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, Czech

Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden,

Switzerland and 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

© 2005 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 62055-31:2005 E
---------------------- Page: 2 ----------------------
EN 62055-31:2005 - 2 -
Foreword

The text of document 13/1344/FDIS, future edition 1 of IEC 62055-31, prepared by IEC TC 13,

Equipment for electrical energy measurement and load control, was submitted to the IEC-CENELEC

parallel vote and was approved by CENELEC as EN 62055-31 on 2005-11-01.
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) 2006-08-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2008-11-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice

The text of the International Standard IEC 62055-31:2005 was approved by CENELEC as a European

Standard without any modification.
__________
---------------------- Page: 3 ----------------------
- 3 - EN 62055-31:2005
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.

NOTE Where an international publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.
Publication Year Title EN/HD Year
IEC 60050-300 2001 International Electrotechnical Vocabulary - -
- Electrical and electronic measurements
and measuring instruments
Part 311: General terms relating to
measurements
Part 312: General terms relating to
electrical measurements
Part 313: Types of electrical measuring
instruments
Part 314: Specific terms according to the
type of instrument
IEC 61000-4-5 1995 Electromagnetic compatibility (EMC) EN 61000-4-5 1995
Part 4-5: Testing and measurement
techniques - Surge immunity test
IEC 61008-1 1996 Residual current operated circuit-
+ A1 (mod) 2002 breakers without integral overcurrent EN 61008-1 2004
protection for household and similar uses
(RCCB's)
Part 1: General rules
IEC 61358 1996 Acceptance inspection for direct EN 61358 1996
connected alternating current static watt-
hour meters for active energy (classes 1
and 2)
IEC/TR 62051 1999 Electricity metering - Glossary of terms - -
IEC 62052-11 2003 Electricity metering equipment (AC) - EN 62052-11 2003
General requirements, tests and test
conditions
Part 11: Metering equipment
IEC 62053-21 2003 Electricity metering equipment (a.c.) - EN 62053-21 2003
Particular requirements
Part 21: Static meters for active energy
(classes 1 and 2)
IEC 62054-21 2004 Electricity metering (a.c.) - Tariff and load EN 62054-21 2004
control
Part 21: Particular requirements for time
switches
---------------------- Page: 4 ----------------------
EN 62055-31:2005 - 4 -
Publication Year Title EN/HD Year
IEC 62055-21 2005 Electricity metering - Payment systems - -
Part 21: Framework for standardization
---------------------- Page: 5 ----------------------
INTERNATIONAL IEC
STANDARD 62055-31
First edition
2005-09
Electricity metering – Payment systems –
Part 31:
Particular requirements –
Static payment meters for active energy
(classes 1 and 2)
 IEC 2005  Copyright - all rights reserved

No part of this publication may be reproduced or utilized in any form or by any means, electronic or

mechanical, including photocopying and microfilm, without permission in writing from the publisher.

International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland

Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch

PRICE CODE
Commission Electrotechnique Internationale XB
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
---------------------- Page: 6 ----------------------
– 2 – 62055-31  IEC:2005(E)
CONTENTS

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

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

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

2 Normative references .......................................................................................................8

3 Terms and definitions .......................................................................................................8

3.1 General payment metering definitions .....................................................................8

3.2 Definitions of tokens..............................................................................................10

3.3 Definitions of token carriers...................................................................................11

3.4 Definitions relating to tokens and token carriers ....................................................13

3.5 Definitions related to load switching ......................................................................14

3.6 Definitions related to timekeeping and tariff control ...............................................15

4 Standard electrical values ..............................................................................................16

5 Mechanical requirements................................................................................................16

5.1 General .................................................................................................................16

5.2 General mechanical requirements .........................................................................16

5.3 Case .....................................................................................................................16

5.4 Window .................................................................................................................16

5.5 Terminals ..............................................................................................................17

5.6 Terminal covers.....................................................................................................17

5.7 Creepage and clearance distances........................................................................17

5.8 Insulating-encased meter of protective class II ......................................................17

5.9 Resistance to heat and fire....................................................................................17

5.10 Protection against penetration of dust and water ...................................................17

5.11 Display and indicators ...........................................................................................17

5.12 Output device........................................................................................................19

5.13 Marking of meter ...................................................................................................19

5.14 Token carrier interface ..........................................................................................19

6 Climatic requirements.....................................................................................................19

6.1 General .................................................................................................................19

6.2 Temperature range................................................................................................20

7 Electrical requirements ...................................................................................................21

7.1 General .................................................................................................................21

7.2 Influence of supply voltage ....................................................................................22

7.3 Power consumption ...............................................................................................24

7.4 Influence of short-time overcurrents ......................................................................24

7.5 Influence of heating...............................................................................................25

7.6 Influence of self-heating ........................................................................................25

7.7 Insulation ..............................................................................................................25

7.8 Electromagnetic compatibility (EMC) .....................................................................25

7.9 Load switching ......................................................................................................27

7.10 Auxiliary output switches .......................................................................................29

7.11 Token carrier acceptor interface test .....................................................................29

8 Metering accuracy requirements.....................................................................................29

---------------------- Page: 7 ----------------------
62055-31  IEC:2005(E) – 3 –

9 Functional requirements .................................................................................................29

9.1 General .................................................................................................................29

9.2 Robustness of meter accounting process ..............................................................30

10 Type test ........................................................................................................................31

Annex A (informative) Functional performance.....................................................................32

A.1 Basic functionalities – prepayment mode .....................................................................32

A.2 Additional functionalities ..............................................................................................39

A.3 System compliance requirements ................................................................................41

Annex B (informative) Reference model for a payment meter...............................................42

B.1 General .......................................................................................................................42

B.2 Generalised payment meter instance ...........................................................................43

B.3 Functions in a single-part payment meter ....................................................................45

Annex C (normative) Performance requirements for payment meters with load

switching utilisation categories UC2, UC3 and UC4 ..............................................................49

C.1 Load switching capabilities ..........................................................................................49

C.2 Normal operation.........................................................................................................49

C.3 Electrical endurance....................................................................................................50

C.4 Line to load voltage surge withstand ............................................................................51

C.5 Fault current making capacity ......................................................................................52

C.6 Short-circuit current carrying capacity..........................................................................53

C.7 Minimum switched current ...........................................................................................55

C.8 Dielectric strength........................................................................................................55

C.9 Sequence of tests........................................................................................................56

Annex D (normative) Requirements of timekeeping..............................................................57

D.1 General .......................................................................................................................57

D.2 Synchronous clocks.....................................................................................................58

D.3 Crystal-controlled clocks..............................................................................................58

D.4 Tests of timekeeping accuracy.....................................................................................59

D.5 Effects of disturbances on timekeeping........................................................................60

Table C.1 – Summary of test currents for UC2, UC3 and UC4...............................................49

Table C.2 – Test sequence and sample plan.........................................................................56

---------------------- Page: 8 ----------------------
– 4 – 62055-31  IEC:2005(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICITY METERING – PAYMENT SYSTEMS –
Part 31: Particular requirements –
Static payment meters for active energy
(classes 1 and 2)
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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any

equipment declared to be in conformity with an IEC Publication.

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

other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and

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 62055-31 has been prepared by IEC technical committee 13:

Equipment for electrical energy measurement and load control.
The text of this standard is based on the following documents:
FDIS Report on voting
13/1344/FDIS 13/1355/RVD

Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

---------------------- Page: 9 ----------------------
62055-31  IEC:2005(E) – 5 –

IEC 62055 consists of the following parts, under the general title Electricity metering –

Payment systems:
Part 21: Framework for standardization
Part 31: Static payment meters for active energy (Classes 1 and 2)

Part 41: Standard Transfer Specification – Application layer protocol for one-way token

carrier systems

Part 51: Standard Transfer Specification – Physical layer protocol for one-way numeric and

magnetic card token carriers

The committee has decided that the contents of this publication will remain unchanged until

the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in

the data related to the specific publication. At this date, the publication will be

• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.
—————————
Under consideration.
---------------------- Page: 10 ----------------------
– 6 – 62055-31  IEC:2005(E)
INTRODUCTION

Payment meters are used in situations where the supply of electrical energy to the load may

be interrupted or its restoration enabled under the control of the payment meter in relation to

a payment tariff agreed between the customer and the supplier. The payment meter is part of

a system that uses token carriers to pass payment information as tokens between a vending

network and the payment meters that include the meter accounting process.

The functions of a payment meter are to measure electrical energy consumed and to

decrement the available credit value in accordance with the metered consumption, and

possibly in accordance with the passing of time. This available credit value is incremented as

the result of payments made to the electricity supplier, and the meter accounting process

continuously calculates the balance of available credit held by the customer. When the

available credit value has been decremented to a predetermined value that is related to the

payment mode in use, a switch is used to interrupt the supply to the customer’s load.

However, additional features may be present in the payment meter, which prevent or delay

the opening of the switch, or limit further consumption to a low load level. Such “social”

features may include the provision of an emergency credit facility, the possibility of operation

in a fixed-payment mode, and the inhibiting of interruptions for certain periods of time.

In return for the payment (usually in cash) and depending on the particular type of system, the

customer may be issued with a single-use token on a disposable token carrier for the

equivalent value, or a reusable token carrier may be credited with that value, or the token may

be transmitted directly to the meter via a communications network (a so-called virtual token

carrier). “One-way” and “two-way” data transfer systems may be used, and the token carriers

may be: physical devices such as smart cards, or other electronic devices, or magnetic cards;

virtual token carriers where the token information is transferred by a remote communications

system; or numeric token carriers where sequences of digits are issued on a paper receipt

and entered via a keypad on the meter.
IEC 62051 provides some details of payment metering terminology in Clause 17.
---------------------- Page: 11 ----------------------
62055-31  IEC:2005(E) – 7 –
ELECTRICITY METERING – PAYMENT SYSTEMS –
Part 31: Particular requirements –
Static payment meters for active energy (classes 1 and 2)
1 Scope

This part of IEC 62055 applies to newly manufactured, static watt-hour payment meters of

accuracy classes 1 and 2 for direct connection, for the measurement of alternating current

electrical energy consumption of a frequency in the range 45 Hz to 65 Hz that include a load

switch for the purpose of interruption or restoration of the electricity supply to the load in

accordance with the current value of the available credit maintained in the payment meter. It

does not apply to static watt-hour payment meters where the voltage across the connection

terminals exceeds 600 V (line-to-line voltage for meters for polyphase systems).

It applies to payment meters for indoor application only, where the payment meter shall be

mounted as for normal service (i.e. together with a specified matching socket where

applicable).

Payment meters are implementations where all the main functional elements are incorporated

in a single enclosure, together with any specified matching socket. There are also multi-part

installations where the various main functional elements, such as the measuring element, the

user interface unit, token carrier interface, and the load switch are implemented in more than

one enclosure, involving additional interfaces. This part of IEC 62055 does not apply to multi-

part payment metering installations.

Functional requirements that apply to payment meters are also defined in this part of

IEC 62055, and include informative basic functional requirements and tests for the

prepayment mode of operation in Annex A. Allowances are made for the relatively wide range

of features, options, alternatives, and implementations that may be found in practice. The

diverse nature and functionality of payment meters prevent the comprehensive specification

of detailed test methods for all of these requirements. However, in this case, the requirements

are stated in such a way that tests can then be formulated to respect and validate the specific

functionality of the payment meter being tested.

This part of IEC 62055 does not cover specific functionality or performance requirements for

safety, circuit protection, isolation or similar purposes that may be specified through reference

to other specifications or standards.

This part of IEC 62055 does not cover software requirements. Software requirements for

basic energy meter metrology are under consideration for the IEC 62059 series of standards,

and in other organisations.

This part of IEC 62055 covers type-testing requirements only. For acceptance testing, the

concepts given in IEC 61358 may be used as a basic guideline.
Dependability aspects are addressed in the IEC 62059 series of standards.

This part of IEC 62055 does not cover conformity tests and system compliance tests that may

be required in connection with legal or other requirements of some markets.
---------------------- Page: 12 ----------------------
– 8 – 62055-31  IEC:2005(E)
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.
IEC 62051:1999, Electricity metering – Glossary of terms.

IEC 61358:1996, Acceptance inspection for direct-connected alternating current static watt-

hour meters for active energy (classes 1 and 2)

IEC 62052-11:2003, Electricity metering equipment (AC) – General requirements, tests and

test conditions – Part 11: Metering equipment

IEC 62053-21:2003, Electricity metering equipment (AC) – Particular requirements – Part 21:

Static meters for active energy (classes 1 and 2)

IEC 60050-300:2001, International Electrotechnical Vocabulary – Electrical and electronic

measurements and measuring instruments – Part 311: General terms relating to

measurements – Part 312: General terms relating to electrical measurements – Part 313:

Types of electrical measuring instruments – Part 314: Specific terms according to the type of

instrument
IEC 61000-4-5:1995, Electromagnetic compatibility (EMC) – Part 4-5: Testing and
measurement techniques – Surge immunity test

IEC 61008-1:1996, Residual current operated circuit-breakers without integral overcurrent

protection for household and similar uses (RCCBs) – Part 1: General rules
Amendment 1 (2002)

IEC 62055-21:2005, Electricity metering – Payment systems – Part 21: Framework for

standardisation

IEC 62054-21:2004, Electricity metering (a.c.) – Tariff and load control – Part 21: Particular

requirements for time switches
3 Terms and definitions

For the purposes of this part of IEC 62055, the terms and definitions given in IEC 60050-300,

IEC 62051, IEC 62052-11, and IEC 62055-21, as well as the following, apply.

Where there is a difference between definitions in IEC 62055-31 and those contained in other

referenced IEC standards, then those defined in IEC 62055-31 shall take precedence.

NOTE Some of these definitions cancel and replace those for the same term in IEC 62051, including some terms

in Clause 17 of that standard.
3.1 General payment metering definitions
3.1.1
a.c. withstand voltage

r.m.s. value of sinusoidal power frequency voltage that the equipment can withstand during

tests made under specified conditions and for a specified time
[IEC 60050:1987 604-03-40, modified]
---------------------- Page: 13 ----------------------
62055-31  IEC:2005(E) – 9 –
3.1.2
available credit value

value of available credit (in monetary or energy units) usable for further consumption that is

either stored in the payment meter or calculated by it whenever required
3.1.3
fault current

current flowing at a given point of a network resulting from a fault at another point of this

network
[IEC 60050:1986 603-02-25]
3.1.4
load interface

terminal(s) where the customer’s load circuit is connected to the payment meter, or to a

specified matching socket, where applicable
3.1.5
multi-part installation
...

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