IEC 61850-9-2:2004

INTERNATIONAL IEC
STANDARD 61850-9-2
First edition
2004-04
Communication networks and systems
in substations –
Part 9-2:
Specific Communication Service Mapping (SCSM) –
Sampled values over ISO/IEC 8802-3

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INTERNATIONAL IEC
STANDARD 61850-9-2
First edition
2004-04
Communication networks and systems
in substations –
Part 9-2:
Specific Communication Service Mapping (SCSM) –
Sampled values over ISO/IEC 8802-3
 IEC 2004  Copyright - all rights reserved
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mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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– 2 – 61850-9-2  IEC:2004(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6

1 Scope.7
2 Normative references.7
3 Terms and definitions .9
4 Abbreviations.9
5 Communication stack.10
5.1 Overview of the protocol usage .10
5.2 Client/server services and communication profiles .11
5.3 SV service and communication profile .13
5.4 Restrictions.15
6 Mapping of IEC 61850-7-2 and IEC 61850-7-3 Data Attributes.16
7 Mapping of IEC 61850-7-2 classes and services .16
7.1 Classes of SV data sets .16
7.2 Definition of SV data sets .16
8 Mapping of the model for the transmission of sampled values .16
8.1 Overview.16
8.2 Mapping of the multicast sampled value control block class and services .16
8.3 Mapping of the unicast sampled value control block class and services .17
8.4 Mapping of the update of the sampled value buffer.19
8.5 Additional definitions for the transmission of sampled values.19
8.6 Definitions for basic data types .21
9 Conformance.21
9.1 Notation.21
9.2 PICS .21
10 Substation Configuration language (SCL).23

Annex A (informative) ISO/IEC 8802-3 frame format and ASN.1 basic encoding rules.24
Annex B (informative) Process bus architectures .27
Annex C (informative) Multicast address selection .28

Figure 1 – OSI reference model and profiles.10
Figure 2 – Structure of the tag header .14
Figure 3 – Concatenation of several ASDU's into one frame .19
Figure A. 1 – ISO/IEC 8802-3 frame format .24
Figure A.2 – Basic encoding rules format .25
Figure A.3 – Format of the tag octets .25
Figure A.4 – Example for an ASN.1 coded APDU frame structure.26
Figure B.1 – Alternative process bus architectures .27

61850-9-2  IEC:2004(E) – 3 –
Table 1 – Service requiring client/server communication profile .11
Table 2 – Service and protocols for client/server communication A-Profile .12
Table 3 – Service and Protocols for Peer TCP/IP T-Profile.12
Table 4 – Service requiring SV communication profile .13
Table 5 – Service and protocols for SV communication A-Profile .13
Table 6 – SV T-Profile .13
Table 7 – Default Virtual LAN IDs and priorities .14
Table 8 – Assigned Ethertype values .15
Table 9 – MMS TypeDescription definition for MSVCB MMS structure.17
Table 10 – Mapping of multicast sampled value services .17
Table 11 – MMS TypeDescription definition for USVCB MMS Structure.18
Table 12 – Mapping of unicast sampled value services .18
Table 13 – Encoding for the transmission of the sampled value buffer .20
Table 14 – Encoding for the basic data types.21
Table 15 – PICS for A-Profile support.22
Table 16 – PICS for T-Profile support.22
Table 17 – SV conformance statement.22
Table 18 – Definitions for SV SCL.23

– 4 – 61850-9-2  IEC:2004(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
COMMUNICATION NETWORKS AND SYSTEMS IN SUBSTATIONS –

Part 9-2: Specific Communication Service Mapping (SCSM) –
Sampled values over ISO/IEC 8802-3

FOREWORD
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International Standard IEC 61850-9-2 has been prepared by IEC technical committee 57:
Power systems management and associated information exchange.
The text of this standard is based on the following documents:
FDIS Report on voting
57/690/FDIS 57/709/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.

61850-9-2  IEC:2004(E) – 5 –
IEC 61850 consists of the following parts, under the general title Communication networks
and systems in substations:
Part 1: Introduction and overview
Part 2: Glossary
Part 3: General requirements
Part 4: System and project management

Part 5: Communication requirements for functions and device models
Part 6: Configuration description language for communication in electrical substations
related to IEDs
Part 7-1: Basic communication structure for substation and feeder equipment – Principles and
models
Part 7-2: Basic communication structure for substation and feeder equipment – Abstract

communication service interface (ACSI)
Part 7-3: Basic communication structure for substation and feeder equipment – Common data
classes
Part 7-4: Basic communication structure for substation and feeder equipment – Compatible
logical node classes and data classes
Part 8-1: Specific Communication Service Mapping (SCSM) – Mappings to MMS (ISO 9506-1
and ISO 9506-2) and to ISO/IEC 8802-3
Part 9-1: Specific Communication Service Mapping (SCSM) – Sampled values over serial
unidirectional multidrop point to point link
Part 9-2: Specific Communication Service Map
...