IEC PAS 62055-41:2003

IEC/PAS 62055-41
Edition 1.0
2003-09
Electricity metering –
Payment metering systems –
Part 41:
Standard Transfer Specification

PUBLI C LY AVAI LABLE SPECI F I CATI O N

Reference number
IN TER N A TION AL
E L E C T R OT E CHNI CA L
IEC/PAS 62055-41
C O MMI S S I O N
IEC/PAS 62055-41
Edition 1.0
2003-09
Electricity metering –
Payment metering systems –
Part 41:
Standard Transfer Specification

PUBLI C LY AVAI LABLE SPECI F I CATI O N

Reference number
IN TER N A TION AL
E L E C T R OT E CHNI CA L
IEC/PAS 62055-41
C O MMI S S I O N
CONTENTS
FOREWORD. ii

Rationalized User Specification –

Electricity sales systems
Part 6: Interface standards
Section 6: Standard transfer specification/Credit dispensing unit – Electricity dispenser –

Categories of token and transaction data fields. 1

Section 7: Standard transfer specification/Credit dispensing unit – Electricity dispenser –
Token encoding and data encryption and decryption . 17

Section 8: Standard transfer specification/Disposable magnetic token technology – Token
encoding format and physical token definition. 49

Section 9: Standard transfer specification/Numeric token technology – Token encoding
format and physical token definition . 63

Part 7: Standard transfer specification/Management of cryptographic keys. 74

Annex – Standard Transfer Specification – Synopsis. 103

Page i
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
ELECTRICITY METERING – PAYMENT METERING SYSTEMS –

Part 41: Standard Transfer Specification

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,

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.
A PAS is a technical specification not fulfilling the requirements for a standard, but made available to the
public and established in an organization operating under given procedures.
IEC-PAS 62055-41 was submitted by the STS (Standard Transfer Specification) Association and has been
processed by IEC technical committee 13: Equipment for electrical energy measurement and load control.
The text of this PAS is based on the This PAS was approved for

following document: publication by the P-members of the
committee concerned as indicated in
the following document:
Draft PAS Report on voting
13/1298/PAS 13/1301/RVD
Following publication of this PAS, the technical committee or subcommittee concerned will investigate the
possibility of transforming the PAS into an International Standard.
An IEC-PAS licence of copyright and assignment of copyright has been signed by the IEC and the STS
association and is recorded at the Central Office.
This PAS shall remain valid for no longer than 3 years starting from 2003-09. The validity may be
extended for a single 3-year period, following which it shall be revised to become another type of
normative document, or shall be withdrawn.
Page ii
NRS 009-6-6:2002
ICS 29.240.99; 91.140.50
Edition 1.1
Edition 1: Incorporating Amendment No. 1:2002
ISBN 0-626-14112-5
Rationalized User Specification

ELECTRICITY SALES SYSTEMS
Part 6: Interface standards
Section 6: Standard transfer
specification/Credit dispensing unit —
electricity dispenser — Categories of
token and transaction data fields

Requirements for applications in the
Electricity Supply
Industry
N R S
Gr 8
®Standard Transfer Specification

2 Copyright © 2003, STS; 2003, IEC

This Rationalized User Specification is

issued by the NRS Project
on behalf of the
User Group given in the foreword

and is not a standard as contemplated in the Standards Act, 1993 (Act 29 of 1993).

Rationalized user specifications allow user
organizations to define the performance and quality
requirements of relevant equipment.

Rationalized user specifications may, after a certain

application period, be introduced as national standards.

Amendments issued since publication
Amdt No. Date Text affected
1 May 2002 Notice: Information added on STS compliance.
Foreword.
Clause 2: Normative references updated.
Clause 3: Note added to clarify abbreviation “ED”.
4.3.2: Reference to NRS 009-4-2 changed to
annex A of NRS 009-6-7.
Amendment 1 was compiled to aid understanding of the specification internationally, in preparation for its
submission to the IEC, for consideration as an IEC PAS. This consolidated edition 1.1 is technically
identical to, and replaces, NRS 009-6-6:1997, which is published by the SABS under ISBN 0-626-11656-
2, for which the SABS holds publishing copyright.

Correspondence to be directed to Printed copies obtainable from

South African Bureau of Standards South African Bureau of Standards
(Electrotechnical Standards) Private Bag X191

Private Bag X191 Pretoria 0001
Pretoria 0001
Telephone: (012) 428-7911
Fax: (012) 344-1568
E-mail: sales@sabs.co.za
Website: http://www.sabs.co.za

COPYRIGHT RESERVED
Printed on behalf of the NRS Project in the Republic of South Africa
by the South African Bureau of Standards
1 Dr Lategan Road, Groenkloof, Pretoria
®Standard Transfer Specification

NOTICE
Revised February 2003
™
This section of NRS 009-6 specifies requirements that are part of the standard transfer specification
(STS). The intellectual property rights of the STS are owned by the STS Association.
The cryptographic algorithms published in this section are those for existing installations and future
releases shall make provision for a choice of several state of the art algorithms for implementation
according to the strength of the security required in the target installation. It has to be noted that this
specification already allows for such alternative algorithms by inference of the data element “Algorithm
Code” (see NRS009-6-6 section 4.3.5 ).
Implementation of an STS compliant system will require access to encryption and decryption tables and
the STS encryption keys, which are made available under license conditions through membership of the
STS Association. Details of requirements to become a member of the STS Association can be obtained
from the contact details given below.
Amdt 1
Suppliers who are to claim that their equipment complies with the STS are required to have the relevant
equipment accredited by the STS Association or its agent. Such equipment will be permitted to carry a
mark that signifies compliance with the STS.
Application for accreditation of equipment as compliant with the STS can be made to the
STS Association:
email@sts.org.za
Amdt 1
Fax number +27(21) 914 3930
Postal address:
PO Box 2332
Durban
South Africa
Further information concerning the STS Association can be obtained from its website:
http://www.sts.org.za
Amdt 1
A Section 21 “not for gain” company incorporated in the Republic of South Africa.
®Standard Transfer Specification

4 Copyright © 2003, STS; 2003, IEC

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®Standard Transfer Specification

1 NRS 009-6-6:2002
Contents
Page
Foreword. 2

Introduction . 4

Key words. 5

1 Scope. 7

2 Normative references. 7
3 Terms, definitions and abbreviated terms. 8
4 Requirements. 8
4.1 General. 8
4.2 Categories of token. 8
4.3 Transaction data fields . 9

®Standard Transfer Specification

6 Copyright © 2003, STS; 2003, IEC

NRS 009-6-6:2002 2
Foreword
This section of NRS 009-6 has been prepared on behalf of the Electricity Suppliers Liaison Committee

(ESLC) and has been approved by it for use by supply authorities in South Africa.

Amendment 1 to this section of NRS 009-6 provides for direct cross-references to NRS 009-4-2, which is
not part of the standard transfer specification. The requirements of NRS 009-4-2 that are relevant to this
section of NRS 009-6 have been included in an annex to NRS 009-6-7.

Amdt 1
NRS 009 is based on Eskom specification MC114, Requirements specification for a common vending
system for electricity dispensing systems, and consists of the following parts, under the general title
Electricity sales systems:
Part 0: Standard transfer specification — Synopsis. (Under consideration.)
Part 1: Glossary and system overview. (Withdrawn, superseded by SABS 1524-0.)
Part 2: Functional and performance requirements.
Section 1: System master stations.
Section 2: Credit dispensing units.
Section 3: Security modules.
Section 4: Standard token translators.
Section 5: Error handling.
Part 3: Database format.
Part 4: National electricity meter cards and associated numbering standards.
Section 1: National electricity meter cards.
Section 2: National electricity meter numbers.
Part 5: Testing of subsystems.
Part 6: Interface standards.
Section 1: Credit dispensing unit — Standard token translator.
Section 2: System master station — main frame.
Section 3: System master station — Credit dispensing unit (previously NRS 009-3).
Section 4: Data transfer by physical media — System master station — Credit dispensing
unit.
Section 5: Not allocated
Section 6: Standard transfer specification — Credit dispensing unit — Electricity dispenser —
Categories of token and transaction data fields.
Section 7: Standard transfer specification — Credit dispensing unit — Electricity dispenser —
Token encoding and data encryption and decryption.
Section 8: Standard transfer specification — Disposable magnetic token technology — Token
encoding format and physical token definition.
Section 9: Standard transfer specification — Numeric token technology — Token encoding
format and physical token definition.
Part 7: Standard transfer specification — The management of cryptographic keys.

ISBN 0-626-14112-5
®Standard Transfer Specification

3 NRS 009-6-6:2002
An amendment to the first edition of this section of NRS 009-6 was submitted by the STS Association in
2002, which was endorsed by a Working Group that comprised the following members:

S J van den Berg (Chairman) Mangaung Municipality

P A Johnson (Project leader) NRS Project Management Agency

V Bissett City of Cape Town
R Devparsad eThekwini Electricity

J O’Kennedy Eskom Distribution

V E Rengecas SABS
M Singh eThekwini Electricity
D W van Reenen City Power Johannesburg
J Westenraad City of Tshwane
The working group acknowledges the contribution of S Leigh, who compiled the standard transfer
specification while with Conlog, under a contract to Eskom. The intellectual property rights to the STS
have been ceded to the STS Association. See the notice at the front of this section of NRS 009-6.
A Manufacturers’ Interest Group (MIG) was consulted on the amendment of this section of NRS 009-6.
The MIG comprised the following members:
R Hill Circuit Breaker Industries
S Leigh Prism
R Lewis Tellumat SA
F Pucci Schneider (t/a Conlog)
A Stoner Energy Measurements Limited
D Taylor Actaris Measurements
The Working Group was appointed by the ESLC, which, for the of approval of amendment 1, comprised
the following members:
R Wienand(Chairman) eThekwini Metropolitan Council, AMEU
M N Bailey Distribution Technology, Eskom
A J Claasen Electrical Engineering Standards, SABS
P Crowdy Distribution Technology, Eskom
B de Jager Mangaung Electricity, AMEU
W Dykman City of Tshwane, AMEU
A H L Fortmann AMEU
P A Johnson Technology Standardization, Eskom
J Machinjike Transmission, Eskom
D M Michie Nelson Mandela Metropolitan Municipality, AMEU
S V Moodley City Power Johannesburg (Pty) Ltd

R van der Riet City of Cape Town, AMEU
J S van Heerden SABS NETFA
D J van Wyk uMhlathuze Electricity, AMEU
Recommendations for corrections, additions or deletions should be addressed to the NRS Project
Manager, c/o SABS, Private Bag X191, Pretoria, 0001.
®Standard Transfer Specification

8 Copyright © 2003, STS; 2003, IEC

NRS 009-6-6:2002 4
Introduction
A variety of proprietary electricity dispensers (EDs) and vending systems have been developed. The

proprietary systems are however not compatible with each other. This gave rise to a definite need among

the major users to move towards standardized solutions in addressing operational problems experienced
where various types of ED and vending equipment have to be operated simultaneously. A standard
transfer specification (STS) was developed that would allow for the application of EDs from any
manufacturer in an electricity sales (vending) system. The STS is specified in sections 6 to 9 of

NRS 009-6 and NRS 009-7.
Amdt 1
The physical device used to transport the information from the vending system to the ED is referred to as
a token. The STS specifies the use of two types token. (see NRS 009-6-8 and NRS 009-6-9), namely the
disposable magnetic token and the numeric token.
The STS is designed primarily for applications in prepayment electricity sales systems where a secure
method for the transfer of purchased electricity units from the credit dispensing unit (CDU) to the ED is
required. However, it also caters for the transfer of units of other utility types, for example water or gas.
An overview of the component parts of the STS, as specified in sections 6 to 9 of NRS 009-6, is given in
figure 1.
Token and data
definition
NRS 009-6-6
Clear text
NRS 009-6-7
Encryption
Encrypted text
NRS 009-6-8 NRS 009-6-9
Token encoding
Data stream
Physical production
Disposable magnetic
Numeric token
token
technology stack
Technology stack
Figure 1 — An overview of the component parts of the STS
®Standard Transfer Specification

5 NRS 009-6-6:2002
The STS specifies the following:

a) categories of tokens (NRS 009-6-6);

b) transaction data fields (NRS 009-6-6);

c) encryption algorithm (NRS 009-6-7);

d) token encoding format and physical token definition for disposable magnetic tokens (NRS 009-6-8);

and
e) token encoding format and physical token definition for numeric tokens (NRS 009-6-9).
Key words
Electricity sales systems; Payment systems; Prepayment; Standard transfer specification; Electricity
dispenser; Token.
®Standard Transfer Specification

10 Copyright © 2003, STS; 2003, IEC

NRS 009-6-6:2002 6
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®Standard Transfer Specification

7 NRS 009-6-6:2002
SPECIFICATION
Electricity sales systems
Part 6: Interface standards
Section 6: Standard transfer specification/Credit dispensing unit —

Electricity dispenser — Categories of token and transaction data fields

Requirements for applications in the Electricity Supply Industry
1 Scope
This section of NRS 009-6, in conjunction with NRS 009-6-7, NRS 009-6-8 and NRS 009-6-9, specifies
the standard transfer specification (STS), i.e. the minimum standard for transferring units of credit and
information between a common vending system (CVS) and a compliant electricity dispenser (ED).
This section of NRS 009-6 is intended for use by manufacturers of EDs that have to accept tokens that
comply with the STS and manufacturers of vending systems that produce STS-compliant tokens.
2 Normative references
The following standard and specifications contain provisions which, through reference in this text,
constitute provisions of this section of NRS 009-6. At the time of publication, the editions indicated were
valid. All standards and specifications are subject to revision, and parties to agreements based on this
section of NRS 009-6 are encouraged to investigate the possibility of applying the most recent editions of
the documents listed below. Information on currently valid national and international standards and
specifications can be obtained from the South African Bureau of Standards.
NRS 009-6-7:2002, Electricity sales systems — Part 6: Interface standards — Section 7: Standard
transfer specification/Credit dispensing unit — Electricity dispenser — Token encoding and data
encryption and decryption.
Amdt 1
NRS 009-6-8:1997, Electricity sales systems — Part 6: Interface standards — Section 8: Standard
transfer specification/Disposable magnetic token technology — Token encoding format and physical
token definition.
Amdt 1
NRS 009-6-9:1997, Electricity sales systems — Part 6: Interface standards — Section 9: Standard
transfer specification/Numeric token technology — Token encoding format and physical token definition.
Amdt 1
SABS 1524-0:1997, Electricity dispensing systems — Part 0: Glossary of terms and system overview.

®Standard Transfer Specification

12 Copyright © 2003, STS; 2003, IEC

NRS 009-6-6:2002 8
3 Terms, definitions and abbreviated terms

For the purposes of this section of NRS 009, the definitions and abbreviations given in SABS 1524-0

apply.
NOTE Throughout this section of NRS 009-6, reference is made to “ED” (electricity dispenser), which is synonymous with

“prepayment meter”.
Amdt 1
4 Requirements
4.1 General
An STS-compliant ED shall be capable of reading and interpreting all of the categories of token
successfully. Where an optional transaction is not implemented in an ED, the ED shall indicate that the
token has been rejected.
4.2 Categories of token
Three categories of token exist, namely:
a) credit transfer tokens, that are normally used by customers (see 4.2.1);
b) management tokens that are not ED specific (see 4.2.2); and
c) management tokens that are ED specific (see 4.2.3).
The use of management tokens is normally restricted to utility personnel.
4.2.1 Credit transfer tokens
The transactions that shall be available using credit transfer tokens are listed in table 1.
Table 1 — Credit transfer token transactions
1 2 3
Description of transaction STS-compliant ED ED specific
implementation
Transfer electricity units to ED Mandatory Yes
Transfer water units to ED Mandatory if the ED supports water Yes

metering
Transfer gas units to ED Mandatory if the ED supports gas Yes
metering
Transfer connection time units to ED Mandatory if the ED supports Yes
connection time metering
Transfer currency units to ED Mandatory if the ED supports Yes
currency metering
4.2.2 Non-ED-specific management tokens
The transaction that shall be available using non-ED-specific management tokens is a transaction that
will initiate an ED test. This transaction is intended for use by installation or maintenance personnel.
®Standard Transfer Specification

9 NRS 009-6-6:2002
4.2.3 ED-specific management tokens

The transactions that shall be available using ED-specific management tokens are listed in table 2.

Table 2 — ED-specific management token transactions

1 2 3
Description of transaction Target user STS compliant ED

implementation
Set maximum power load
Installation or maintenance Mandatory
personnel
Clear ED electricity credit Installation or maintenance Mandatory
personnel
Clear ED water credit Installation or maintenance Mandatory if the ED supports water
personnel metering
Clear ED gas credit Installation or maintenance Mandatory if the ED supports gas
personnel metering
Clear ED connection time credit Installation or maintenance Mandatory if the ED supports
personnel connection time metering
Clear currency credit Installation or maintenance Mandatory if the ED supports
personnel currency metering
Set tariff rate Installation or maintenance Mandatory if the ED supports
personnel currency metering
Set ED key Installation personnel Mandatory
Clear tamper condition Maintenance personnel Optional
Set phase power unbalance limit Installation or maintenance Implementation is mandatory in a
personnel poly-phase ED (not applicable in the
case of a single-phase ED)
Set water factor Installation or maintenance Mandatory if the ED supports water
personnel metering
4.3 Transaction data fields
4.3.1 General
The transaction data fields specify the information required to produce the various transactions and the
format in which this data will be given. The data fields relevant to each credit transfer transaction are given
in table 3. The data fields relevant to the actions effected by non-ED-specific management tokens are

given in table 4. The data fields relevant to the transactions effected by ED-specific management tokens
are given in table 5.
4.3.2 ED number
The ED number (also known as the meter number) is an 11-digit number, as defined in annex A of
NRS 009-6-7.
Amdt 1
®Standard Transfer Specification

14 Copyright © 2003, STS; 2003, IEC

NRS 009-6-6:2002 10
4.3.3 Tariff index
The tariff index is a 2-digit number used in a tariff table to assign the relevant tariff rate to the customer to

whom the ED is allocated.
4.3.4 Token technology code
The token technology code is a 2-digit number that is used for the unique identification of the token

technology used in an ED.
4.3.5 Algorithm code
The algorithm code is a 2-digit number that is used for the unique identification of the cryptographic
algorithm used in the transfer of information via the token.
4.3.6 Supply group code
The supply group code (SGC) is a 6-digit number that is used for the unique identification of the supply
group to which the ED belongs.
NOTE The allocation of SGCs is administered nationally in order to avoid their being duplicated. (See annex B of NRS 009-4-1
for information on the use and allocation of SGCs.)
4.3.7 Date of issue
The date of issue is an 8-digit number in the format YYYYMMDD, where YYYY indicates the year of
issue, MM indicates the month of issue, and DD indicates the day of issue.
4.3.8 Time of issue
The time of issue is a 6-digit number in the format HHMMSS, where HH indicates the hour of issue
(range 00 to 23), MM indicates the minute of issue, and SS indicates the second of issue.
4.3.9 Transfer amount
The transfer amount is an 8-digit number indicating the amount to be transferred, expressed in the
appropriate units (see column 9 of table 3).
4.3.10 Maximum power load permitted

The maximum power load permitted in watts, is an 8-digit number.
4.3.11 Phase power unbalance limit
The phase power unbalance limit in watts, is an 8-digit number.
4.3.12 Water factor
The water factor is a 6-digit number used to convert pulses from the water transducer into a form that the
ED can use.
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11 NRS 009-6-6:2002
Table 3 — Definition of data fields for credit transfer transactions
1 2 3 4 5 6 7 8 9 10
Description of ED number Tariff Token Algorith Supply Date of Time of Data ED implementation
transaction range index techno- m code group issue issue
range logy range code
code range
range
Transfer electricity 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall increase its available credit
units to ED Unit of measure:  by the value on the token and store the
100 watt-hours token identifier to prevent token reuse
Transfer water units 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall increase its available credit
to ED Unit of measure: by the value on the token and store the
hectolitres token identifier to prevent token reuse
Transfer gas unites 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall increase its available credit
to ED Unit of measure to by the value on the token and store the
be defined token identifier to prevent token reuse
Transfer connection 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall increase its available credit
time units to ED Unit of measure: by the value on the token and store the
minutes token identifier to prevent token reuse

Transfer currency 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall increase its available credit
units to ED Unit of measure to by the value on the token and store the
be defined token identifier to prevent token reuse
Table 4 — Definition of data fields for transactions effected by non-ED-specific management tokens
1 2 3 4 5 6 7 8 9 10
Description of ED number Tariff Token Algorith Supply Date of Time of Data ED Implementation
management range index techno- m code group code issue issue
transaction range logy range range
code
range
Initiate ED test N/A N/A 0 - 99 N/A N/A N/A N/A Test number 0 - 99 The ED shall react to the test number
specified. The test numbers are defined
in NRS 009-6-7
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16 Copyright © 2003, STS; 2003, IEC
NRS 009-6-6:2002 12
Table 5 — Definition of data fields for transactions effected by ED-specific management tokens
1 2 3 4 5 6 7 8 9 10
Description of ED number Tariff Token Algorith Supply Date of Time of Data ED implementation
management index techno- m code group code issue issue
transaction range logy range range
code
range
Set maximum power 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall update its maximum
load Unit of measure: power load register and store the
watts token identifier to prevent token reuse
Clear credit 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Credit type. Refer to The ED shall set the relevant credit
NRS 009-6-7 for balance(s) to zero, and store the
actual definitions token identifier to prevent token reuse
Set tariff rate 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS To be defined The ED shall update its tariff register
and store the token identifier to
prevent token reuse
Set dispenser key 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS New supply group The ED shall overwrite the existing key
code version
number 0 - 99.
New tariff index
0 - 99
Clear tamper 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS N/A The ED shall reset the tamper status
condition register and store the token identifier
to prevent token reuse
Set phase power 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 – 18201624 The ED shall update its maximum
unbalance limit Unit of measure: phase power unbalance register and
watts store the token identifier to prevent
token reuse
Set water factor 0 - 99999999999 0 - 99 0 - 99 0 - 99 0 - 999999 YYYYMMDD HHMMSS Units 0 - 65535 The ED shall update its water factor
register and store the token identifier
to prevent token reuse
sabs pta
®Standard Transfer Specification

NRS 009-6-7:2002
ICS 29.240.99; 35.240.60; 91.140.50

Edition 2.3
Edition 2: Incorporating
Amendment No. 3:2002
Rationalized User Specification

ELECTRICITY SALES SYSTEMS
Part 6: Interface standards
Section 7: Standard transfer
specification/Credit dispensing unit —
Electricity dispenser — Token encoding
and data encryption and decryption

Requirements for applications in the Electricity Supply
Industry
N R S
Gr 10
®Standard Transfer Specification

18 Copyright © 2003, STS; 2003, IEC

This Rationalized User Specification is

issued by the NRS Project
on behalf of the
User Group given in the foreword

and is not a standard as contemplated in the Standards Act, 1993 (Act 29 of 1993).

Rationalized user specifications allow user

organizations to define the performance and quality
requirements of relevant equipment.

Rationalized user specifications may, after a certain

application period, be introduced as national standards.

Amendments issued since publication
Amdt No. Date Text affected
1 May 2001 Subclause 4.2.7:
a) removed the table of manufacturer codes,
b) added reference of website for table of
manufacturer codes,
c) added contact details of NRS Projects Manager
for list of manufacturer codes,
d) added reference of specification for meter
number.
2 May 2002 Notice: Information added on STS compliance.
Foreword.
Clause 2: Normative references updated.
Clause 3: Note added to clarify abbreviation “ED”.
Subclause 4.2.7 and 4.4. Reference to NRS 009-4-2
changed to reference annex A.
Annex A added.
3 Feb 2003 Technical corrigendum: Figure 11 and 12, binary
value of CRC check sum
Figure 2 , Encryption Algorithm 3 replaced by KMC
function and removed accompanying note
Amendment 2 was compiled to aid understanding of the specification internationally, in
preparation for its submission to the IEC, for consideration as an IEC PAS. This consolidated
edition 2.2 is technically identical to, and replaces, the consolidated edition of
NRS 009-6-7:2001, which is published by the SABS under ISBN 0-626-13498-6, for which the
SABS holds publishing copyright.
Amendment 3 was compiled to clarify concerns raised by IEC members, pertaining to the

IEC/PAS submission and to clarify the apparent conflict in the meaning of Encryption Algorithm 3
as reflected in this document and in the Synopsis document.

Correspondence to be directed to Printed copies obtainable from
South African Bureau of Standards South African Bureau of Standards
(Electrotechnical Standards) Private Bag X191
Private Bag X191 Pretoria 0001
Pretoria 0001
Telephone: (012) 428-7911
Fax: (012) 344-1568
®Standard Transfer Specification

E-mail: sales@sabs.co.za
Website: http://www.sabs.co.za

COPYRIGHT RESERVED
Printed on behalf of the NRS Project in the Republic of South Africa

by the South African Bureau of Standards

1 Dr Lategan Road, Groenkloof, Pretoria

®Standard Transfer Specification

20 Copyright © 2003, STS; 2003, IEC

NOTICE
Revised February 2003
Ô
This section of NRS 009-6 specifies requirements that are part of the standard transfer

specification (STS). The intellectual property rights of the STS are owned by the STS

Association.
The cryptographic algorithms published in this section are those for existing installations and
future releases shall make provision for a choice of several state of the art algorithms for
implementation according to the strength of the security required in the target installation. It
has to be noted that this specification already allows for such alternative algorithms by
inference of the data element “Algorithm Code” (see NRS009-6-6 section 4.3.5 ).
Implementation of an STS compliant system will require access to encryption and decryption
tables and the STS encryption keys, which are made available under license conditions
through membership of the STS Association. Details of requirements to become a member of
the STS Association can be obtained from the contact details given below.
Amdt 2
Suppliers who are to claim that their equipment complies with the STS are required to have the
relevant equipment accredited by the STS Association or its agent. Such equipment will be
permitted to carry a mark that signifies compliance with the STS.
Application for accreditation of equipment as compliant with the STS can be made to the STS
Association:
email@sts.org.za
Fax number +27(21) 914 3930
Postal address:
PO Box 2332
Durban
South Africa
Further information concerning the STS Association can be obtained from its website:
http://www.sts.org.za
A section 21 “not for gain” company incorporated in the Republic of South Africa.
®Standard Transfer Specification

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®Standard Transfer Specification

22 Copyright © 2003, STS; 2003, IEC

1 NRS 009-6-7:2002
Contents
Page
Foreword . 2

Introduction . 4

Key words . 4

1 Scope . 5

2 Normative references . 5
3 Terms, definitions and abbreviated terms . 6
4 Requirements . 6
4.1 Bit allocation tables . 6
4.2 Field calculations . 9
4.3 STS security . 16
4.4 Default ED key generation module . 17
4.5 Preventing ED-specific token reuse . 17
4.6 Encryption algorithm 1 . 18
4.7 Decryption algorithm 1 . 20
4.8 Data encryption example . 22
4.9 Data decryption example . 24
Annex
A Format of meter numbers used for STS compliant meters . 25
Bibliography . 27

®Standard Transfer Specification

NRS 009-6-7:2002 2
Foreword
This section of NRS 009-6 has been adopted by the Electricity Suppliers Liaison Committee (ESLC)
and has been approved by it for use by supply authorities in South Africa.

Amendment 2 to this section of NRS 009-6 provides for deletion of direct cross-references to

NRS 009-4-2, which is not part of the standard transfer specification. The requirements of

NRS 009-4-2 that are relevant to this section of NRS 009-6 have been included in an annex.

NRS 009 is based on Eskom specification MC114, Requirements specification for a common vending

system for electricity dispensing systems, and consists of the following parts, under the general title
Electricity sales systems:
Part 0: Standard transfer specification — Synopsis. (Under consideration.)
Part 1: Glossary and system overview. (Withdrawn, superseded by SABS 1524-0.)
Part 2: Functional and performance requirements.
Section 1: System master stations.
Section 2: Credit dispensing units.
Section 3: Security modules.
Section 4: Standard token translators.
Section 5: Error handling.
Part 3: Database format.
Part 4: National electricity meter cards and associated numbering standards.
Section 1: National electricity meter cards.
Section 2: National electricity meter numbers.
Part 5: Testing of subsystems.
Part 6: Interface standards.
Section 1: Credit dispensing unit — Standard token translator interface.
Section 2: System master station — Main frame. (Suspended; see annex A of NRS 009-2-1.)
Section 3: System master station — Credit dispensing unit. (Previously NRS 009-3).
Section 4: Data transfer by physical media — System master station — Credit dispensing
unit.
Section 5: Not allocated.
Section 6: Standard transfer specification — Credit dispensing unit — Electricity dispenser —
Categories of token and transaction data fields.

Section 7: Standard transfer specification — Credit dispensing unit — Electricity dispenser —
Token encoding and data encryption and decryption.
Section 8: Standard transfer specification — Disposable magnetic token technology —
Token encoding format and physical token definition.
Section 9: Standard transfer specification — Numeric token technology — Token encoding
format and physical token definition.
Part 7: Standard transfer specification — The management of cryptographic keys.

®Standard Transfer Specification

24 Copyright © 2003, STS; 2003, IEC

3 NRS 009-6-7:2002
An amendment to edition 2.1 of this section of NRS 009-6 was submitted by the STS Association in

2002, which was endorsed by a Working Group that comprised the following members:

S J van den Berg (Chairman) Mangaung Municipality

P A Johnson (Project leader) NRS Project Management Agency

V Bissett City of Cape Town
R Devparsad eThekwini Electricity

J O’Kennedy Eskom Distribution

V E Rengecas SABS
M Singh eThekwini Electricity
D W van Reenen City Power Johannesburg
J Westenraad City of Tshwane
A Manufacturers’ Interest Group (MIG) was consulted on the amendment of this section of NRS 009.
The MIG comprised the following members:
R Hill Circuit Breaker Industries
S Leigh Prism
R Lewis Tellumat SA
F Pucci
...