IEC 62055-31:2005

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

IEC 62055-31:2005 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 Functional requirements that apply to payment meters are also defined and include informative basic functional requirements and tests for the prepayment mode of operation in Annex A. This bilingual version (2013-05) corresponds to the monolingual English version, published in 2005-09.

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

La CEI 62055-31:2005 s'applique à des compteurs à paiement statiques de wattheures nouvellement fabriqués de classe 1 et 2 pour raccordement direct, pour la mesure de la consommation d'énergie électrique en courant alternatif d'une fréquence allant de 45 Hz à 65 Hz incluant un commutateur de charge ayant pour but d'interrompre ou de rétablir la fourniture d'électricité à la charge en fonction de la valeur courante du crédit disponible maintenu dans le compteur à paiement. Elle ne s'applique pas aux compteurs à paiement dont la tension entre bornes de raccordement dépasse 600 V (tension entre phases pour les compteurs de systèmes polyphasés). Elle s'applique aux compteurs à paiement pour applications intérieures seulement, où le compteur à paiement doit être monté comme en service normal. Les exigences fonctionnelles qui s'appliquent aux compteurs à paiement sont également définies et comportent des exigences fonctionnelles informatives de base et des essais pour le mode de fonctionnement par prépaiement de l'Annexe A. La présente version bilingue (2013-05) correspond à la version anglaise monolingue publiée en 2005-09.

General Information

• Status: Published
• Publication Date: 25-Sep-2005
• ICS: 91.140.50 - Electricity supply systems
• Technical Committee: TC 13 - Electrical energy measurement and control
• Drafting Committee: WG 15 - TC 13/WG 15
• Current Stage: DELPUB - Deleted Publication
• Start Date: 21-Jun-2022
• Completion Date: 26-Oct-2025

Relations

• Corrected By: IEC 62055-31:2005/COR1:2007 - Corrigendum 1 - Electricity metering - Payment systems - Part 31: Particular requirements - Static payment meters for active energy (classes 1 and 2)
• Effective Date: 05-Sep-2023
• Revised: IEC 62055-31:2022 - Electricity metering - Payment systems - Part 31: Particular requirements - Static payment meters for active energy (classes 0,5, 1 and 2)
• Effective Date: 05-Sep-2023

Overview - IEC 62055-31:2005 (Static payment meters)

IEC 62055-31:2005 is an International Electrotechnical Commission (IEC) standard that defines particular requirements for static payment (prepayment) watt‑hour meters measuring active energy in accuracy classes 1 and 2. It covers direct‑connected, indoor payment meters operating at frequencies of 45 Hz to 65 Hz, with line‑to‑line voltages up to 600 V, and that include a load switch to interrupt or restore supply based on the meter’s available credit. Functional and test requirements for prepayment operation are provided (informative Annex A), together with electrical, mechanical, climatic and metering accuracy requirements.

Key topics and technical requirements

• Meter scope and limits: Direct connection, indoor use, voltage ≤ 600 V (line‑to‑line), frequency 45–65 Hz, accuracy classes 1 & 2.
• Load switching: Requirements for switch performance, endurance and safety for interruption/restoration of supply tied to credit state.
• Metering accuracy: Active energy measurement requirements, metrological tests and type test regimes.
• Functional requirements: Accounting process, decrementing/incrementing of credit, emergency credit/social features, and robustness of meter accounting. Annex A details prepayment mode functions.
• Token interfaces: Definitions and requirements for token carriers (magnetic, numeric, smart cards, virtual tokens) and token transfer interfaces.
• Electrical and EMC: Insulation, surge withstand, electromagnetic compatibility and power consumption rules.
• Mechanical and climatic: Enclosures, terminals, displays, ingress protection and environmental operating ranges.
• Timekeeping and tariff control: Clock accuracy, synchronous/crystal timekeeping and tests (Annex D).
• Type testing and conformity: Test sequences, performance tests and normative annexes (including load switching categories UC2–UC4 in Annex C).

Practical applications

• Deployment of prepayment electricity meters in residential, commercial and communal settings where pay‑as‑you‑go or token‑based billing is used.
• Systems requiring reliable load control tied to credit (e.g., municipal utilities, remote vending networks).
• Evaluation and specification of meters for indoor installations where safety, metrology and token handling must meet international requirements.

Who should use this standard

• Meter manufacturers designing static payment meters (accuracy classes 1 & 2)
• Utilities and energy service providers specifying prepayment solutions and procurement criteria
• Test laboratories and certification bodies conducting type tests and conformity assessments
• System integrators and vendors of token vending and payment systems

Related standards

• IEC 62055 series (framework and communications): Part 21, Part 41, Part 51
• IEC 62051 (payment metering terminology) - referenced for definitions and system concepts

Keywords: IEC 62055-31, static payment meters, prepayment meters, electricity metering, load switch, active energy, accuracy classes 1 and 2, token carriers, IEC standard.

Standards Content (Sample)

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)
Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the

60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,

edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the

base publication incorporating amendment 1 and the base publication incorporating

amendments 1 and 2.
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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: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale XB
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 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

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

– 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
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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 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.

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.
– 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.

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.

– 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]

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
payment metering installation where the functional elements comprising the measuring
element(s); register(s), storage, and control; meter accounting process; user interface
including any physical token carrier interface; any virtual token carrier interface; load
switch(es); auxiliaries; plus supply interface and load interface are not arranged in the form of
a payment meter, but instead are partitioned into two or more units that require appropriate
mounting, connection, and commissioning
[IEC 62051, 17.45, modified]
3.1.6
payment meter
electricity meter with additional functionality that can be operated and controlled to allow the
flow of energy according to agreed payment modes
NOTE It includes the following functional elements: measuring element(s); register(s), storage, and control; meter
accounting process and any time-based functions; user interface including any physical token carrier interface; any
virtual token carrier interface; load switch(es); auxiliaries; plus supply interface and load interface. A payment
meter takes the form of a single unit, or a main unit that also employs a single specified matching socket for the
supply interface and load interface. In either case. some payment meter implementations may allow for some or all
of any time-based functions to be provided by an external unit connected to the payment meter, such as a time
switch, a ripple control receiver, or a radio receiver.
[IEC 62051, 17.47, modified]
NOTE Refer to Figure B.1 for the generalised block diagram of a payment meter instance.
3.1.7
payment metering installation
set of payment metering equipment installed and ready for use at a customer’s premises. This
includes mounting the equipment as appropriate, and where a multi-part installation is
involved, the connection of each unit of equipment as appropriate. It also includes the
connection of the supply network to the supply interface, the connection of the customer’s
load circuit to the load interface, and the commissioning of the equipment into an operational
state as a payment metering installation
3.1.8
prepayment mode
payment mode in which automatic interruption occurs when available credit is exhausted

– 10 – 62055-31  IEC:2005(E)
3.1.9
specified matching socket
in relation to a payment meter arranged as a plug-in unit, a specified matching socket

comprises a base with jaws to accept and connect to the plug-in unit, terminals for connection

of the supply network and the consumer load circuit, and appropriate secure fixing and

sealing arrangements. The payment meter is capable of meeting the relevant type-testing

requirements when it is properly installed in any specified matching socket

3.1.10
supply interface
terminal(s) where the supply network is connected to a payment meter, or to a specified

matching socket, where applicable
3.1.11
time-based credit
payment meter accounting functions that deal with the calculation and transacting of a (social)
grant of credit that is released on a scheduled time basis
NOTE See IEC 62055-21:2005, 13.8.3.
3.1.12
user interface
that part of a payment meter or payment metering installation that allows the customer to
monitor and operate the installation. It may also facilitate meter reading and inspection, and
metering services activities. Where physical token carriers are employed, it includes a token
carrier interface
3.2 Definitions of tokens
3.2.1
token
information content including an instruction issued on a token
carrier by a vending or management system that is capable of subsequent transfer to and
acceptance by a specific payment meter, or one of a group of meters, with appropriate
security
[IEC 62051, 17.66, modified]
NOTE In a more general sense, the token refers to the instruction and information being transferred, while the
token carrier refers to the physical device being used to carry the instruction and information, or to the
communications medium in the case of a virtual token carrier.
subset of data elements, containing an instruction and
information, that is present in the APDU of the application layer of the POS to Token Carrier
Interface, and which is also transferred to the payment meter by means of a token carrier

3.2.2
credit token
value token
token that represents an amount of credit in monetary or energy value for transfer from the
vending point to the payment meter
3.2.3
duplicate token
token that contains the same information as a token that has already been issued, and hence
may also be a valid token
NOTE 1 This is not the same as a replacement token (refer also to 3.4.9).
NOTE 2 A duplicate token is a reissue of the same token that was previously issued and is identical to it in all
aspects; whereas a replacement token is a newly generated token in place of a previously generated token and
may not be identical to it in all aspects.

62055-31  IEC:2005(E) – 11 –
3.2.4
multiple-use token
token (such as a test token) that can be used for more than one successful session in a

payment meter or possibly with each in a group of meters. These are typically used for meter

reading or service purposes on repeated occasions

3.2.5
no-value token
token that does not result in a financial advantage or disadvantage to the consumer, which

may contain meter configuration data, or instructions to perform certain tests, or to display
certain values on the user interface, or to retrieve certain data from the meter and return it on
a token carrier
NOTE This is as opposed to value token.
3.2.6
replacement token
see 3.4.9
NOTE This is not the same as a duplicate token (see 3.2.3).
3.2.7
single-use token
token (such as a credit token) that can only be used for one successful session in a payment
meter
3.2.8
valid token
in relation to a specific payment meter (or group of payment meters), a token that is capable
of being processed successfully by the meter(s)
3.2.9
value token
see credit token (3.2.2)
3.3 Definitions of token carriers
3.3.1
token carrier
devices or media used to transport and present token
information to payment meters, such as printed paper, magnetic card, electronic memory
card/key, microprocessor card, or data communications networks. The token carrier may also
carry ancillary control or monitoring information to or from the payment meter, depending
upon system type and requirements

medium that is used in the physical layer of the POS to Token
Carrier Interface, onto which the token is modulated or encoded, and which serves to carry
the token from the point where it is generated to the remote payment meter, where it is
received
3.3.2
blank token carrier
physical token carrier that has not been processed at the vending point or elsewhere and
hence contains no specific data

– 12 – 62055-31  IEC:2005(E)
3.3.3
disposable token carrier
token carrier that is not capable of further use once it has been accepted or used, such as a

paper-based magnetic card
3.3.4
machine-readable token carrier

physical or virtual token carrier carrying token information that is capable of being read and

processed automatically on presentation to an appropriate payment meter, without further

manual operation
EXAMPLE A token employing a magnetic card as the token carrier.
3.3.5
memory token carrier
physical token carrier containing a non-volatile memory device, in which the token is
electronically encoded and stored while it is being transported
3.3.6
microprocessor token carrier
physical token carrier containing a microprocessor device with non-volatile memory, in which
the token is electronically encoded and stored while it is being transported. In addition to the
token information, the microprocessor token carrier may also contain an application
programme and associated data
3.3.7
numeric token carrier
token transfer method where the token information can be represented in a secure manner by
a visible and human readable sequence of numeric digits (typically 20 digits printed on a
receipt)
NOTE They may be entered into a payment meter via a keypad interface for evaluation and action.
3.3.8
one-way token carrier
physical or virtual token carrier which is used for the transfer of credit and possibly tariff and
configuration data in a single direction from the vending point or the management system to
the payment meter
3.3.9
physical token carrier
token carrier that requires a human to transport it at least part of the way between the point
where the token is loaded onto the token carrier and the point where it is retrieved from the

token carrier by the payment meter
NOTE Examples of physical token carriers are: printed numbers; magnetic cards; printed bar codes; electronic
storage in memory devices such as smart cards or memory keys; and audio messages dictated by interactive voice
response equipment.
3.3.10
rechargeable token carrier
refer to 3.3.11 reusable token carrier
3.3.11
reusable token carrier
rechargeable token carrier
physical token carrier that can be used for multiple sessions for transportation of tokens

62055-31  IEC:2005(E) – 13 –
3.3.12
two-way token carrier
physical or virtual token carrier which is used for the transfer of credit and/or tariff and

configuration data from the vending point or management system to the payment meter and

response data from the payment meter back to the vending point or management system for

further processing, where response data may possibly return on a subsequent vending

transaction
NOTE Response data may contain consumption information, tamper information, accountancy information and
token status with or without time and date stamps.

3.3.13
virtual token carrier
token carrier that does not require a human to transport it between the point where the token
is loaded onto the token carrier and the point where it is retrieved from the token carrier by
the payment meter
NOTE Examples of virtual token carriers are: modems on PLC, PSTN, GSM, GPRS and Radio; LAN; WAN and
direct local connection.
3.4 Definitions relating to tokens and token carriers
3.4.1
physical token carrier interface
complete interface protocol stack that includes any token carrier acceptor or keypad for a
physical token carrier, the physical layer protocol and application layer protocol, plus any
intermediate protocol layers
3.4.2
token acceptance
recognition of the successful completion of the processing of any token that was presented to
the payment meter
NOTE Typically, this might involve the addition of token credit to the meter’s accounting register, cancellation of
the token information from the token carrier so as to prevent subsequent acceptance by any meter, and a visible
indication to the user on the user interface. Similarly, this may also be applicable to any tariff or configuration data
included on the token carrier.
3.4.3
token cancellation
1) process of erasing or invalidating information contained in a valid token upon its
acceptance by a payment meter, to prevent its reuse;
2) process of erasing or invalidating information contained in a token after it has been
created, but before it is presented to a payment meter. This typically happens when the
vending operator makes a mistake or if a technical problem occurs during the vending

process
3.4.4
token carrier acceptor
physical part of a physical token carrier interface, which mechanically accepts and holds the
token carrier in the correct position for the token transfer process to take place between the
token carrier and the payment meter. Examples are: smart card acceptor; magnetic card
acceptor; memory key acceptor
3.4.5
token carrier charging
loading of a token and tariff or configuration data onto a token carrier at a vending point or a
management system
– 14 – 62055-31  IEC:2005(E)
3.4.6
token carrier interface
token carrier interface permits the manual or automatic entry of tokens into a payment meter

NOTE 1 For example, it may be a keypad for numeric tokens, or a physical token carrier acceptor, or a

communications connection to a local or remote machine for a virtual token carrier interface.

NOTE 2 The token carrier interface may also be used to pass additional information to or from the payment meter,
such as for the purposes of payment system management.

3.4.7
token credit
value of credit or energy to be transferred from the vending point to the payment meter in the

form of a token on a token carrier
3.4.8
token rejection
this occurs when a token has been presented to but has not been accepted by a payment
meter, and has not been erased or invalidated. In the case of a valid token not being
accepted, the token may be presented and accepted at a later time when conditions allow
3.4.9
token replacement
token that replaces a previously issued token in value. Physical token carriers may require a
blank token carrier to be configured for the customer’s meter
NOTE A replacement token is a newly generated token in place of a previously generated token and may not be
identical to it in all aspects; whereas a duplicate token is a reissue of the same token that was previously issued
and is identical to it in all aspects.
3.4.10
virtual token carrier interface
complete interface protocol stack that includes the physical layer protocol and application
layer protocol, plus any intermediate protocol layers
3.5 Definitions related to load switching
3.5.1
minimum switched current
smallest current that the payment meter is able to make, carry and break at the rated breaking
voltage and under prescribed conditions
3.5.2
prospective current
specified root-mean-square or peak value of current that would flow in a circuit if the unit

under test were to be replaced with a conductor having negligible impedance
3.5.3
rated breaking current
I
c
root-mean-square value of the current that the payment meter is able to make, carry
continuously and break at the rated breaking voltage and under prescribed conditions
3.5.4
rated breaking voltage
U
c
root-mean-square value of the supply voltage, as measured on the output terminals of the
payment meter connected to the load circuit, at which the payment meter is able to break the
rated breaking current
62055-31  IEC:2005(E) – 15 –
3.5.5
trip-free design
design which ensures that the moving contacts of the load switch return to and remain in the

open position when the automatic opening operation is initiated after the initiation of the

closing operation, even if the closing command is maintained

NOTE To ensure proper breaking of the current, which may have been established, it may be necessary that the
contacts momentarily reach the closed position.

3.5.6
utilisation category
performance criteria under which the load switching capability of a payment meter may be

specified to suit the particular requirements of a payment metering installation. The main
criteria being: minimum safety levels, lightning surge withstand, fault current withstand and
switch endurance.
NOTE See also 7.9.3 and 7.9.4
3.6 Definitions related to timekeeping and tariff control
3.6.1
crystal-controlled timekeeping
process of maintaining a payment meter’s time by means of an internal crystal-controlled
clock
3.6.2
external tariff control
control of a payment meter’s time-dependent or consumption-dependent tariff regime (time-
based or consumption-based charges and/or registers) by external signal(s)
3.6.3
external time signal control
control of a payment meter’s internal real-time clock by an external signal
3.6.4
external time synchronisation
synchronisation of a payment meter’s internal real-time clock by an external signal
3.6.5
internal tariff control
control of a payment meter’s time-dependent or consumption-dependent tariff regime (time-
based or consumption-based charges and/or registers) by signals from an internal real-time
clock and switching programme
3.6.6
internal timekeeping
maintenance of a payment meter’s time by its own internal clock facility
3.6.7
operation reserve
maximum period of time after switching off the power supply voltage, during which the
payment meter is capable of maintaining correct time with a specified, relaxed timekeeping
accuracy
3.6.8
reserve restoration time
period of time required for restoring the full operation reserve from the point where the
operation reserve has been completely exhausted

– 16 – 62055-31  IEC:2005(E)
3.6.9
synchronous timekeeping
process of maintaining a payment meter’s time by means of an internal clock synchronised to

a signal derived from the power system frequency

NOTE Payment meters employing synchronous timekeeping may defer to crystal-controlled timekeeping in the
absence of the synchronising signal.

3.6.10
time indication discrepancy
difference between the time displayed by the payment meter and the actual time or, in the

case of synchronous timekeeping, the difference between the time displayed by the payment

meter and the time determined by the network frequency
NOTE The actual time may be obtained by using a reference clock.
3.6.11
timekeeping accuracy
increase or decrease in the time indication discrepancy within a specified time interval
3.6.12
variation of timekeeping accuracy due to an influence quantity
difference in timekeeping accuracy of a payment meter when only one influence quantity
assumes successively two specified values, one of them being the reference value
4 Standard electrical values
Payment meters shall comply with the values given for standard reference voltages, currents,
and frequencies, and the maximum currents given for static meters for direct connection in
Clause 4 of IEC 62052-11.
5 Mechanical requirements
5.1 General
The requirements of Clause 5 of IEC 62052-11 for indoor meters shall apply, where
referenced and augmented herein. Where the payment meter is to be used with a specified
matching socket then these requirements shall be met by the complete
...

IEC 62055-31 ®
Edition 1.0 2005-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electricity metering – Payment systems –
Part 31: Particular requirements – Static payment meters for active energy
(classes 1 and 2)
Equipements de comptage de l'électricité – Systèmes à paiement –
Partie 31: Exigences particulières – Compteurs statiques à paiement d'énergie
active (classes 1 et 2)
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IEC 62055-31 ®
Edition 1.0 2005-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electricity metering – Payment systems –

Part 31: Particular requirements – Static payment meters for active energy

(classes 1 and 2)
Equipements de comptage de l'électricité – Systèmes à paiement –

Partie 31: Exigences particulières – Compteurs statiques à paiement d'énergie

active (classes 1 et 2)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XB
ICS 91.140.50 ISBN 978-2-83220-723-9

– 2 – 62055-31  IEC:2005
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

62055-31  IEC:2005 – 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

– 4 – 62055-31  IEC:2005
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
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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 62055-31 has been prepared by IEC technical committee 13:
Equipment for electrical energy measurement and load control.
This bilingual version (2013-05) corresponds to the monolingual English version, published in
2005-09.
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.
The French version of this standard has not been voted upon.

62055-31  IEC:2005 – 5 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
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.
The contents of the corrigendum of July 2007 have been included in this copy.

—————————
Under consideration.
– 6 – 62055-31  IEC:2005
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.

62055-31  IEC:2005 – 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.

– 8 – 62055-31  IEC:2005
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]

62055-31  IEC:2005 – 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
payment metering installation where the functional elements comprising the measuring
element(s); register(s), storage, and control; meter accounting process; user interface
including any physical token carrier interface; any virtual token carrier interface; load
switch(es); auxiliaries; plus supply interface and load interface are not arranged in the form of
a payment meter, but instead are partitioned into two or more units that require appropriate
mounting, connection, and commissioning
[IEC 62051, 17.45, modified]
3.1.6
payment meter
electricity meter with additional functionality that can be operated and controlled to allow the
flow of energy according to agreed payment modes
NOTE It includes the following functional elements: measuring element(s); register(s), storage, and control; meter
accounting process and any time-based functions; user interface including any physical token carrier interface; any
virtual token carrier interface; load switch(es); auxiliaries; plus supply interface and load interface. A payment
meter takes the form of a single unit, or a main unit that also employs a single specified matching socket for the
supply interface and load interface. In either case. some payment meter implementations may allow for some or all
of any time-based functions to be provided by an external unit connected to the payment meter, such as a time
switch, a ripple control receiver, or a radio receiver.
[IEC 62051, 17.47, modified]
NOTE Refer to Figure B.1 for the generalised block diagram of a payment meter instance.
3.1.7
payment metering installation
set of payment metering equipment installed and ready for use at a customer’s premises. This
includes mounting the equipment as appropriate, and where a multi-part installation is
involved, the connection of each unit of equipment as appropriate. It also includes the
connection of the supply network to the supply interface, the connection of the customer’s
load circuit to the load interface, and the commissioning of the equipment into an operational
state as a payment metering installation
3.1.8
prepayment mode
payment mode in which automatic interruption occurs when available credit is exhausted

– 10 – 62055-31  IEC:2005
3.1.9
specified matching socket
in relation to a payment meter arranged as a plug-in unit, a specified matching socket
comprises a base with jaws to accept and connect to the plug-in unit, terminals for connection
of the supply network and the consumer load circuit, and appropriate secure fixing and
sealing arrangements. The payment meter is capable of meeting the relevant type-testing
requirements when it is properly installed in any specified matching socket
3.1.10
supply interface
terminal(s) where the supply network is connected to a payment meter, or to a specified
matching socket, where applicable
3.1.11
time-based credit
payment meter accounting functions that deal with the calculation and transacting of a (social)
grant of credit that is released on a scheduled time basis
NOTE See IEC 62055-21:2005, 13.8.3.
3.1.12
user interface
that part of a payment meter or payment metering installation that allows the customer to
monitor and operate the installation. It may also facilitate meter reading and inspection, and
metering services activities. Where physical token carriers are employed, it includes a token
carrier interface
3.2 Definitions of tokens
3.2.1
token
information content including an instruction issued on a token
carrier by a vending or management system that is capable of subsequent transfer to and
acceptance by a specific payment meter, or one of a group of meters, with appropriate
security
[IEC 62051, 17.66, modified]
NOTE In a more general sense, the token refers to the instruction and information being transferred, while the
token carrier refers to the physical device being used to carry the instruction and information, or to the
communications medium in the case of a virtual token carrier.
subset of data elements, containing an instruction and
information, that is present in the APDU of the application layer of the POS to Token Carrier
Interface, and which is also transferred to the payment meter by means of a token carrier
3.2.2
credit token
value token
token that represents an amount of credit in monetary or energy value for transfer from the
vending point to the payment meter
3.2.3
duplicate token
token that contains the same information as a token that has already been issued, and hence
may also be a valid token
NOTE 1 This is not the same as a replacement token (refer also to 3.4.9).
NOTE 2 A duplicate token is a reissue of the same token that was previously issued and is identical to it in all
aspects; whereas a replacement token is a newly generated token in place of a previously generated token and
may not be identical to it in all aspects.

62055-31  IEC:2005 – 11 –
3.2.4
multiple-use token
token (such as a test token) that can be used for more than one successful session in a
payment meter or possibly with each in a group of meters. These are typically used for meter
reading or service purposes on repeated occasions
3.2.5
no-value token
token that does not result in a financial advantage or disadvantage to the consumer, which
may contain meter configuration data, or instructions to perform certain tests, or to display
certain values on the user interface, or to retrieve certain data from the meter and return it on
a token carrier
NOTE This is as opposed to value token.
3.2.6
replacement token
see 3.4.9
NOTE This is not the same as a duplicate token (see 3.2.3).
3.2.7
single-use token
token (such as a credit token) that can only be used for one successful session in a payment
meter
3.2.8
valid token
in relation to a specific payment meter (or group of payment meters), a token that is capable
of being processed successfully by the meter(s)
3.2.9
value token
see credit token (3.2.2)
3.3 Definitions of token carriers
3.3.1
token carrier
devices or media used to transport and present token
information to payment meters, such as printed paper, magnetic card, electronic memory
card/key, microprocessor card, or data communications networks. The token carrier may also
carry ancillary control or monitoring information to or from the payment meter, depending
upon system type and requirements
medium that is used in the physical layer of the POS to Token
Carrier Interface, onto which the token is modulated or encoded, and which serves to carry
the token from the point where it is generated to the remote payment meter, where it is
received
3.3.2
blank token carrier
physical token carrier that has not been processed at the vending point or elsewhere and
hence contains no specific data

– 12 – 62055-31  IEC:2005
3.3.3
disposable token carrier
token carrier that is not capable of further use once it has been accepted or used, such as a
paper-based magnetic card
3.3.4
machine-readable token carrier
physical or virtual token carrier carrying token information that is capable of being read and
processed automatically on presentation to an appropriate payment meter, without further
manual operation
EXAMPLE A token employing a magnetic card as the token carrier.
3.3.5
memory token carrier
physical token carrier containing a non-volatile memory device, in which the token is
electronically encoded and stored while it is being transported
3.3.6
microprocessor token carrier
physical token carrier containing a microprocessor device with non-volatile memory, in which
the token is electronically encoded and stored while it is being transported. In addition to the
token information, the microprocessor token carrier may also contain an application
programme and associated data
3.3.7
numeric token carrier
token transfer method where the token information can be represented in a secure manner by
a visible and human readable sequence of numeric digits (typically 20 digits printed on a
receipt)
NOTE They may be entered into a payment meter via a keypad interface for evaluation and action.
3.3.8
one-way token carrier
physical or virtual token carrier which is used for the transfer of credit and possibly tariff and
configuration data in a single direction from the vending point or the management system to
the payment meter
3.3.9
physical token carrier
token carrier that requires a human to transport it at least part of the way between the point
where the token is loaded onto the token carrier and the point where it is retrieved from the
token carrier by the payment meter
NOTE Examples of physical token carriers are: printed numbers; magnetic cards; printed bar codes; electronic
storage in memory devices such as smart cards or memory keys; and audio messages dictated by interactive voice
response equipment.
3.3.10
rechargeable token carrier
refer to 3.3.11 reusable token carrier
3.3.11
reusable token carrier
rechargeable token carrier
physical token carrier that can be used for multiple sessions for transportation of tokens

62055-31  IEC:2005 – 13 –
3.3.12
two-way token carrier
physical or virtual token carrier which is used for the transfer of credit and/or tariff and
configuration data from the vending point or management system to the payment meter and
response data from the payment meter back to the vending point or management system for
further processing, where response data may possibly return on a subsequent vending
transaction
NOTE Response data may contain consumption information, tamper information, accountancy information and
token status with or without time and date stamps.
3.3.13
virtual token carrier
token carrier that does not require a human to transport it between the point where the token
is loaded onto the token carrier and the point where it is retrieved from the token carrier by
the payment meter
NOTE Examples of virtual token carriers are: modems on PLC, PSTN, GSM, GPRS and Radio; LAN; WAN and
direct local connection.
3.4 Definitions relating to tokens and token carriers
3.4.1
physical token carrier interface
complete interface protocol stack that includes any token carrier acceptor or keypad for a
physical token carrier, the physical layer protocol and application layer protocol, plus any
intermediate protocol layers
3.4.2
token acceptance
recognition of the successful completion of the processing of any token that was presented to
the payment meter
NOTE Typically, this might involve the addition of token credit to the meter’s accounting register, cancellation of
the token information from the token carrier so as to prevent subsequent acceptance by any meter, and a visible
indication to the user on the user interface. Similarly, this may also be applicable to any tariff or configuration data
included on the token carrier.
3.4.3
token cancellation
1) process of erasing or invalidating information contained in a valid token upon its
acceptance by a payment meter, to prevent its reuse;
2) process of erasing or invalidating information contained in a token after it has been
created, but before it is presented to a payment meter. This typically happens when the
vending operator makes a mistake or if a technical problem occurs during the vending
process
3.4.4
token carrier acceptor
physical part of a physical token carrier interface, which mechanically accepts and holds the
token carrier in the correct position for the token transfer process to take place between the
token carrier and the payment meter. Examples are: smart card acceptor; magnetic card
acceptor; memory key acceptor
3.4.5
token carrier charging
loading of a token and tariff or configuration data onto a token carrier at a vending point or a
management system
– 14 – 62055-31  IEC:2005
3.4.6
token carrier interface
token carrier interface permits the manual or automatic entry of tokens into a payment meter
NOTE 1 For example, it may be a keypad for numeric tokens, or a physical token carrier acceptor, or a
communications connection to a local or remote machine for a virtual token carrier interface.
NOTE 2 The token carrier interface may also be used to pass additional information to or from the payment meter,
such as for the purposes of payment system management.
3.4.7
token credit
value of credit or energy to be transferred from the vending point to the payment meter in the
form of a token on a token carrier
3.4.8
token rejection
this occurs when a token has been presented to but has not been accepted by a payment
meter, and has not been erased or invalidated. In the case of a valid token not being
accepted, the token may be presented and accepted at a later time when conditions allow
3.4.9
token replacement
token that replaces a previously issued token in value. Physical token carriers may require a
blank token carrier to be configured for the customer’s meter
NOTE A replacement token is a newly generated token in place of a previously generated token and may not be
identical to it in all aspects; whereas a duplicate token is a reissue of the same token that was previously issued
and is identical to it in all aspects.
3.4.10
virtual token carrier interface
complete interface protocol stack that includes the physical layer protocol and application
layer protocol, plus any intermediate protocol layers
3.5 Definitions related to load switching
3.5.1
minimum switched current
smallest current that the payment meter is able to make, carry and break at the rated breaking
voltage and under prescribed conditions
3.5.2
prospective current
specified root-mean-square or peak value of current that would flow in a circuit if the unit
under test were to be replaced with a conductor having negligible impedance
3.5.3
rated breaking current
I
c
root-mean-square value of the current that the payment meter is able to make, carry
continuously and break at the rated breaking voltage and under prescribed conditions
3.5.4
rated breaking voltage
U
c
root-mean-square value of the supply voltage, as measured on the output terminals of the
payment meter connected to the load circuit, at which the payment meter is able to break the
rated breaking current
62055-31  IEC:2005 – 15 –
3.5.5
trip-free design
design which ensures that the moving contacts of the load switch return to and remain in the
open position when the automatic opening operation is initiated after the initiation of the
closing operation, even if the closing command is maintained
NOTE To ensure proper breaking of the current, which may have been established, it may be necessary that the
contacts momentarily reach the closed position.
3.5.6
utilisation category
performance criteria under which the load switching capability of a payment meter may be
specified to suit the particular requirements of a payment metering installation. The main
criteria being: minimum safety levels, lightning surge withstand, fault current withstand and
switch endurance.
NOTE See also 7.9.3 and 7.9.4
3.6 Definitions related to timekeeping and tariff control
3.6.1
crystal-controlled timekeeping
process of maintaining a payment meter’s time by means of an internal crystal-controlled
clock
3.6.2
external tariff control
control of a payment meter’s time-dependent or consumption-dependent tariff regime (time-
based or consumption-based charges and/or registers) by external signal(s)
3.6.3
external time signal control
control of a payment meter’s internal real-time clock by
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