IEC TR 60870-1-3:1997

• Abstract:

  Covers terms which are specifically relevant to telecontrol techniques as well as other terms which are necessary for the understanding of telecontrol standards. Is a technical report of type 3.

• Status: Published
• Publication Date: 08-Oct-2026
• ICS: 01.040.33 - Telecommunications. Audio and video engineering (Vocabularies)
• ICS: 33.200 - Telecontrol. Telemetering
• Technical Committee: TC 57 - Power systems management and associated information exchange
• Drafting Committee: WG 3 - TC 57/WG 3
• Current Stage: PPUB - Publication issued
• Start Date: 28-Apr-1997
• Completion Date: 31-Mar-1997

• Amended By: IEC TR 60870-1-3:1997/AMD1:2026 - Amendment 1 - Telecontrol equipment and systems - Part 1-3: General considerations - Glossary
• Effective Date: 26-Oct-2025

Overview

IEC TR 60870-1-3:1997 is a technical report published by the International Electrotechnical Commission (IEC) that focuses on telecontrol equipment and systems. Specifically, it is Part 1, Section 3 of the standard series, providing a comprehensive glossary of terms used in telecontrol systems and equipment. This report serves as a critical reference for understanding telecontrol techniques and related standards. As a type 3 technical report, it collects and compiles terminology, offering clarity and consistency to engineers, developers, and researchers working with telecontrol technologies.

The document reflects the state of the art as of 1997 and accompanies the broader IEC 60870 standards series, which addresses digital serial transmission used for remote control and monitoring of geographically dispersed processes. Its main purpose is to provide precise definitions for terms that are either specific to telecontrol or essential for comprehending telecontrol standards but not fully covered in the International Electrotechnical Vocabulary (IEV).

Key Topics

• Telecontrol Terminology: This section provides definitions of terms related specifically to telecontrol applications, filling gaps not covered by IEC 60050 (IEV Chapter 371).
• Standardized Definitions: Ensures uniform interpretation of terminology across documentation and implementation efforts, reducing ambiguity.
• Cross-References: Provides references to other IEC vocabularies and standards such as IEC 60050 chapters on reliability, automatic control, and telecommunications, facilitating a holistic understanding.
• Graphical and Letter Symbols: The glossary acknowledges symbols standards (IEC 27, IEC 417, IEC 617, IEC 878), ensuring technical symbols used in telecontrol documentation are standardized.
• Scope of Application: Relevant to telecontrol equipment using digitally encoded serial data transmission for remote control and monitoring - particularly for power system control and associated communication infrastructures.

Applications

• Power System Control: The glossary supports utilities and organizations managing electrical grids through telecontrol systems by providing standardized terminology essential for interoperability and system design.
• Industrial Automation: Facilitates clear communication protocols and equipment interoperability in industrial remote monitoring environments.
• Telecommunication Systems: Assists in defining terms related to the transmission and control of data across geographically dispersed locations.
• Standards Development: Serves as a reference for engineers and technical committees developing or updating telecontrol standards ensuring consistency in terminology.
• Technical Documentation: Improves clarity in manuals, system specifications, and training materials for telecontrol systems by using agreed definitions.

Related Standards

• IEC 60870-1 (General Considerations): Includes other sections covering general principles of telecontrol systems.
• IEC 60870-5 and IEC 60870-6 Series: Standards detailing specific telecontrol protocols and communication between control stations and substations.
• IEC 60050 (International Electrotechnical Vocabulary): Particularly chapters relevant to telecontrol (371), reliability (191), automatic control (351), and data communications (721).
• IEC 27, IEC 417, IEC 617, IEC 878: Standards for graphical and letter symbols used in electrical and telecontrol schematics and equipment documentation.

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Keywords: IEC TR 60870-1-3, telecontrol equipment, telecontrol systems, telecontrol glossary, IEC standards, remote control systems, digital serial data transmission, power system control, telecontrol terminology, IEC 60870 series, telecontrol definitions, industrial automation, telecommunication standards.

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This IEC technical report plays a vital role in harmonizing and clarifying the specialized language used within telecontrol systems engineering, ensuring effective communication and international cooperation in telecontrol equipment and system development.

IEC TR 60870-1-3 ®
Edition 2.1 2026-10
TECHNICAL
REPORT
CONSOLIDATED VERSION
Telecontrol equipment and systems -
Part 1-3: General considerations - Glossary
ICS 01.040.33; 33.200 ISBN 978-2-8327-1560-4
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CONTENTS
FOREWORD . 2
INTRODUCTION . 4
INTRODUCTION to Amendment 1 . 4
1 Scope and object . 5
2 Reference documents . 5
3 Definitions . 7

INTERNATIONAL ELECTROTECHNICAL COMMISSION
––––––––
Telecontrol equipment and systems -
Part 1-3: General considerations – Glossary

FOREWORD
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This consolidated version of the official IEC Standard and its amendment has been prepared
for user convenience.
IEC TR 60870-1-3 edition 2.1 contains the second edition (1997-04) [documents 57(Sec)171
and 57/297/RVC] and its amendment 1 (2026-10) [documents 57/2940/DTR and
57/2983/RVDTR].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red text.
A separate Final version with all changes accepted is available in this publication.

The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
report of one of the following types:
• type 1, when the required support cannot be obtained for the publication of an
International Standard, despite repeated efforts;
• type 2, when the subject is still under technical development or where for any other
reason there is the future but no immediate possibility of an agreement on an
International Standard;
• type 3, when a technical committee has collected data of a different kind from that
which is normally published as an International Standard, for example "state of the art".
Technical reports of types 1 and 2 are subject to review within three years of publication to
decide whether they can be transformed into International Standards. Technical reports of
type 3 do not necessarily have to be reviewed until the data they provide are considered to be
no longer valid or useful.
IEC 60870-1-3, which is a technical report of type 3, has been prepared by IEC technical
committee 57: Power system control and associated communications.
This second edition cancels and replaces the first edition published in 1990 and constitutes a
technical revision.
The text of this technical report is based on the following documents:
Committee draft Report on voting
57(Sec)171 57/297/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
INTRODUCTION
Standards and reports on telecontrol equipment and systems produced during the last few
years by IEC technical committee 57 in different documents of series IEC 60870-5 and
IEC 60870-6 use a certain number of terms with specific meanings in telecontrol applications
that are not yet defined in IEC 60050(371): International Electrotechnical Vocabulary (IEV) –
Chapter 371: Telecontrol (1984). In most of the documents of the 60870 series, glossaries
related to the particular document already exist. Nevertheless, the collection of relevant terms
in this document is useful for the reader of the above-mentioned documents.
This section of IEC 60870-1 presents in alphabetic order these terms and their definitions. It
also presents a comprehensive means of referring to terms with particular meaning in
telecontrol systems and equipment that should also be used in future telecontrol
documentation.
INTRODUCTION to Amendment 1
Amendment 1 to IEC TR 60870-1-3:1997 contains an update of the terminology used in the
IEC 60870 series.
1 Scope and object
This technical report applies to telecontrol equipment and systems with coded bit serial data
transmission for monitoring and control of geographically widespread processes.
This section of IEC 60870-1 covers those terms which are specifically relevant to telecontrol
techniques as well as other terms which are necessary for the understanding of telecontrol
standards.
This report also gives, where applicable, references to other dictionaries of electrical and
electronic terms.
Terms which are considered to be well known by readers of telecontrol standards are not
included in this report. This applies particularly in the field of communications where such
terms as, for example, "information" and "bit" are commonplace and well understood.
2 Reference documents
The following standards contain provisions which, through reference in this text, constitute
provisions of this section of the IEC 60870 series. At the time of publication, the editions of
the reference documents indicated were valid. All standards are subject to revision, so
readers are encouraged to investigate the possibility of applying the most recent editions of
the standards indicated below. Members of IEC and ISO maintain registers of currently valid
International Standards.
IEC 60050(191): 1990, International Electrotechnical Vocabulary (IEV) – Chapter 191:
Dependability and quality of service
IEC 60050(351): 1997, International Electrotechnical Vocabulary (IEV) – Chapter 351:
Automatic control
IEC 60050(371): 1984, International Electrotechnical Vocabulary (IEV) – Chapter 371:
Telecontrol
IEC 60050(721): 1992, International Electrotechnical Vocabulary (IEV) – Chapter 721:
Telegraphy, facsimile and data communication
IEC 60870-1-4: 1994, Telecontrol equipment and systems – Part 1: General considerations –
Section 4: Basic aspects of telecontrol data transmission and organization of standards
IEC 60870-5 and IEC 60870-6
IEC 60870-2-1: 1995, Telecontrol equipment and systems – Part 2: Operating conditions –
Section 1: Power supply and electromagnetic compatibility
IEC 60870-5-3: 1992, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 3: General structure of application data
IEC 60870-5-4: 1993, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 4: Definition and coding of application information elements
IEC 60870-5-5: 1995, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 5: Basic application functions
IEC 60870-5-101: 1995, Telecontrol equipment and systems – Part 5: Transmission protocols
– Section 101: Companion standard for basic telecontrol tasks
IEC 60870-6-501: 1995, Telecontrol equipment and systems – Part 6: Telecontrol protocols
compatible with ISO standards and ITU-T recommendations – Section 501: TASE.1 Service
definitions
IEC 60870-6-502: 1995, Telecontrol equipment and systems – Part 6: Telecontrol protocols
compatible with ISO standards and ITU-T recommendations – Section 502: TASE.1 Protocol
definitions
ISO/IEC 2382-9: 1995, Information technology – Vocabulary – Part 9: Data communication
ISO/IEC 3309: 1993, Information technology – Telecommunications and information exchange
between systems – High-level data link control (HDLC) procedures – Frame structure
ISO/IEC 4335: 1993, Information technology – Telecommunications and information exchange
between systems – High-level data link control (HDLC) procedures – Elements of procedures
ISO 7498-1: 1994, Information technology – Open Systems Interconnection – Basic
Reference Model: The Basic Model
ISO 7498-2: 1989, Information processing systems – Open Systems Interconnection – Basic
Reference Model – Part 2: Security Architecture
ISO 8326: 1987, Information processing systems – Open Systems Interconnection – Basic
connection oriented session service definition
ISO TR 8509: 1987, Information processing systems – Open Systems Interconnection –
Service conventions
ISO 8648: 1988, Information processing systems – Open Systems Interconnection – Internal
organization of the Network Layer
ISO/IEC 8824: 1990, Information technology – Open Systems Interconnection – Specification
of Abstract Syntax Notation One (ASN.1)
ISO/IEC 9545: 1994, Information technology – Open Systems Interconnection – Application
Layer structure
ISO/IEC 9646-1: 1994, Information technology – Open Systems Interconnection – Conformance
testing methodology and framework – Part 1: General concepts
ISO/IEC TR 10000-1: 1995, Information technology – Framework and taxonomy of
International Standarized Profiles – Part 1: General principles and documentation
ISO/IEC TR 10000-2: 1995, Information technology – Framework and taxonomy of
International Standarized Profiles – Part 2: Principles and Taxonomy for OSI Profiles
ITU-T X.15: 1984, Definition of terms concerning public data networks
3 Definitions
absolute chronology; time tagging: Method of transmission of changes-of-state so that
transmitted information is accompanied by data giving the registered time at which the change
occurred, within the time resolution. [IEV 371-05-02]
acknowledgement: See positive acknowledgement; negative acknowledgement
acquisition time: Minimum time for correct detection and processing of a change-of-state.
address: Part of a message identifying the source or its destination.
adjusting command: Command used to change the state of operational equipment having
more than two states. [IEV 371-03-10]
alarm: Information for attracting attention to some abnormal state.
NOTE – A transition from a normal into an abnormal state causes a visual and/or audible warning which has to be
acknowledged. A transition from an abnormal into a normal state usually causes a change of indication and, in
some applications, also causes a visual and/or audible warning which has to be acknowledged.
analogue signal: Signal in the form of a continuously variable value.
application association: Co-operative relationship between two application-service-object-
invocations which govern their bilateral use of the Presentation Service for communication of
information and co-ordination of their joint operation. [ISO/IEC 9545]
application entity (AE): Aspects of an application-process pertinent to Open Systems
Interconnection (OSI). [ISO 7498]
application functions: Functions covering the special needs of the process to which a
telecontrol or SCADA system is applied.
The application functions are divided into basic functions and extended processing functions.
application functions (in the sense of the basic reference model): Part of application-
processes which performs the remote communications procedures between application-
processes. [ISO 7498]
application-process: Element within a real open system which performs the information pro-
cessing for a particular application. [ISO 7498]
application profile: Profile defining the use of protocol standards from Open Systems
Interconnection (OSI) layers 5 to 7, to provide for the structured transfer of information
between systems.
application service element: That part of an application-entity which provides an Open
Systems Interconnection (OSI) environment capability, using underlying services when
appropriate. [ISO 7498]
association control service element: Application service element that provides the
exclusive means for establishing and terminating all application-associations. [ISO/IEC 9545]
asynchronous telecontrol transmission: See start-stop telecontrol transmission.
asynchronous transmission: Data transmission in which the time of occurrence of the start
of each character or block of characters is arbitrary; once started, the time of occurrence of
each signal representing a bit within the character or block, has the same relationship to
significant instants of a fixed time base. [ISO 2382-9]
automatic generation control (AGC): See load-frequency control.
auxiliary information: Information used in order to control the operation of a telecontrol
system.
availability: Ability of a unit or system to perform its required function at any given moment.
average transfer time: Average of the transfer time for every case of input of the primary
signal with respect to the telecontrol system. [IEV 371-08-18]
balanced circuit; balanced line; balanced signal pair: Transmission line consisting of two
conductors in the presence of ground, capable of being operated in such a way that, when the
voltages of the two conductors at all transverse planes are equal in magnitude and opposite in
polarity with respect to ground, the currents in the two conductors are equal in magnitude and
opposite in direction.
balanced transmission: Transmission method by which either Data Terminal Equipment (DTE)
of two connected stations may initiate a message transmission at any time. [IEC 60870-1-4]
barrier device: Device for galvanic isolation of telecontrol equipment and the operational
equipment (e.g. a relay, optocoupler or transformer).
base standard: Approved international standard, technical report or ITU-T Recommendation
which is used in the definition of a Profile. [ISO/IEC TR 10000-1]
basic application function (in telecontrol): Transmission procedure that performs a
supervisory or control function that is generally used in telecontrol systems. [IEC 60870-5-5]
Examples: command transmission, event transmission, cyclic transmission, etc.
basic functions: Functions dealing with all types of individual information from and to the
operational equipment and the operator.
basic reference model: See open system interconnection
baud (Bd): Unit of modulation rate or unit of transfer rate of signal elements of constant
duration in a discretely timed or digital signal; the number of baud is equal to the reciprocal of
the duration in seconds of the shortest signal element or of the unit interval in such a signal.
[IEV 721-03-27]
NOTE – For example, if the duration of the unit interval is 20 ms, the modulation rate is 50 Bd.
binary state information: Monitored information of the status of operational equipment which
is characterized by one of two states, for example on/off. [IEV 371-02-03]
bit erasure probability: Probability that a received signal variable used to represent the
value of a bit exceeds specified limits of tolerated signal quality.
bit erasure rate: Ratio of the number of bits received with signals exceeding specified limits
of tolerated signal quality to the total number of bits sent.
bit error probability: Probability that a received bit will be inverted with respect to the
corresponding bit sent. [IEV 371-08-02]
bit error rate: Ratio of the number of bits received inverted to the total number of bits sent.
[IEV 371-08-01]
bit oriented data transmission: See code transparent data transmission
bit oriented code: See transparent code
bit rate: Speed at which bits are transmitted, usually expressed in bits per second (bits/s).
block: Sequence of bits transmitted as a unit, generally subdivided into fields for conveying
information bits and error check bits.
block code: Sequence of information bits completed by bits used for error detection or error
correction.
block error probability: Probability that a block will be incorrectly received. [IEV 371-08-04]
block error rate: Ratio of the number of blocks incorrectly received to the total number of
blocks sent. [IEV 371-08-03]
blocked: When the value of the information object is blocked for transmission, the value
remains in the state that was acquired before it was blocked. Blocking and deblocking may be
initiated e.g. by a local lock or a local automation cause.
blocked spontaneous data transfer: Similar to "spontaneous data transfer", but the initiating
application process waits a certain time for more spontaneous data before transmission to
allow a more efficient data transfer in the case of bursts of spontaneous data.
blocking: Function performed by an (N)-entity to map multiple (N)-service-data-units into one
(N)-protocol-data-unit. [ISO 7498]
Bose Chaudhuri Hocquenghem-code (BCH-code): Cyclic code that can be defined by a
generator polynomial; every code word is a multiple of that polynomial.
breaking capability: Current that a device is capable of breaking at a stated recovery voltage
under prescribed conditions of use and behaviour.
bridge: Relay node of a data network in which transmission paths with different protocol
definitions of the physical layer are interconnected.
broadcast command: Command which is addressed to operational equipment at several or
all outstations of a telecontrol network. [IEV 371-03-16]
brouter: Relay node of a data network which performs both the functionality of a bridge and
of a router with one single unit. Used to interconnect data networks to create a single logical
network.
byte: Ordered set of a specified number of binary digits operated upon as an entity.
[IEV 721-02-11]
NOTE – The word "byte" without qualification may be used as a synonym for octet.
call control procedure: Implementation of a set of protocols necessary to establish and
release a call. [ISO 2382-9]
call establishment: Sequence of events for the establishment of a data connection. [ITU-T X.15]
call release: Sequence of events for the release of a data connection. [IEC 60870-1-4]
calling: Process of transmitting selection signals in order to establish a connection between
data stations. [ISO 2382-9]
centralized absolute chronology: Transmission of changes-of-state information with
absolute chronology from different locations containing synchronized clocks. [IEV 371-05-04]
NOTE – The resulting accuracy specification considers separating capability, absolute chronology and clock
synchronization errors.
change-of-state announcement: Announcement of a demand for the transmission of event
information. [IEV 371-04-03]
channel: Single path for transmitting electric signals, usually in distinction from other parallel
paths.
NOTE – The word "path" is to be interpreted in a broad sense to include separation by frequency division or time
division. The term "channel" may signify either a one-way path, providing transmission in one direction only, or a
two-way path, providing transmission in two directions.
channel selecting telecontrol system; common diagram telecontrol system: Telecontrol
system in which the control centre or master controlling station selects any one of a number
of outstations or controlled stations by switching the receiver and, if necessary, the command
sender from one circuit to another. [IEV 371-07-10] [IEC 60050-371:1984, 371-07-10,
modified – removal of "or master station"]
check command: Command for the purpose of ensuring that the telecontrol equipment is
functioning correctly. [IEV 371-04-08]
check sequence; check sum: Part of a message used for error checking or error correcting
purposes.
ciphertext: Data product through the use of encipherment (encryption). The semantic content
of the resulting data is not available without the knowledge of the encipherment used.
circuit switched data network (CSDN); circuit switched network: Arrangement of
dedicated (time-division or space-division) switching facilities to provide telecommunication
service based on circuit switching methods. These could be a circuit switched data network or
switched telephone network. [IEC 60870-1-4]
circuit switched public data network (CSPDN): Circuit switched network established and
operated by public services for the utilization of public users.
circuit switching: Process that, on demand, connects two or more data terminal equipment
and permits the exclusive use of a data circuit between them until the connection is released.
[ISO 2382-9]
closed user group: Group of specified users of a data network that permits communication
among them and precludes communication with all other users of the service or services.
[ISO 2382-9]
NOTE – A user may belong to more than one closed user group.
code: Specified relation between two sets of characters.
code transparent data transmission; bit oriented data transmission: Data transmission
method that does not depend on bit sequence structures used by the data source.
code-independent data communication: Mode of data communication that uses a
character-oriented protocol that does not depend on the character set or code used by the
data source. [ISO 2382-9]
code-transparent data communication: Mode of data communication that uses a bit-
oriented protocol that does not depend on the bit sequence structure used by the data source.
[ISO 2382-9]
combined station: In high level data link control (HDLC), part of a data station that supports
the combined control functions of the data link and that generates commands and responses
for transmission and interprets received commands and responses. [ISO 2382-9]
NOTE – Specific responsibilities assigned to a combined station include initialization of control signal interchange,
organization of data flow, interpretation of received commands and generation of appropriate responses and
actions regarding error control and error recovery functions at the data link level.
command: Information used to cause a change of state of operational equipment. [IEV 371-03-01]
command direction: Direction from the controlling location to the controlled process. This is
normally the direction from the master control centre or controlling station to the outstation or
controlled station.
common alarm: Combination of all individual alarms into one alarm. [IEV 371-02-14]
common diagram telecontrol system: See channel selecting telecontrol system
common mode voltage: Mean of the voltages appearing between each conductor and a
specified reference, usually earth or frame. [IEC 60870-1-2]
companion standard: Companion standard adds semantics to the definitions of the basic
standard or a function profile. This may be expressed by defining particular uses for
information objects or by defining additional information objects, service procedures and
parameters of the basic standard. [IEC 60870-5-5 and IEC 60870-5-101]
NOTE – Companion standards do not alter the standards to which they refer, but make explicit the relationship
between those used together for a specific domain of application.
composite configuration: See hybrid configuration
compound data field (CP): Sequence of data fields with successive bit allocations that forms
an information element. [IEC 60870-5-5]
concentrator station: Station in a hierarchical telecontrol network where monitored
information from outstations or controlled stations is concentrated for transmission to the
master control centre or controlling station and where the command information from a master
control centre or controlling station is distributed to the outstations or controlled stations. [IEV
371-06-02] [IEC 60050-371:1984, 371-06-02, modified – addition of "or controlled stations",
"master station" replaced with "control centre or controlling station", addition of "or controlled
stations"]
concrete syntax: Those aspects of the rules used in the formal specification of data which
embody a specific representation of that data. [ISO 7498]
confirm (primitive): Representation of an interaction in which a service-provider indicates, at
a particular service-access-point, completion of some procedure previously invoked, at that
service-access-point, by an interaction represented by a request primitive. [ISO TR 8509]
conformance testing: Tests to determine whether an implementation of a protocol conforms
with specified capabilities and options, and whether it satisfies specific static and dynamic
conformance requirements (see static conformance requirements, dynamic conformance
requirements).
(N)-connection: Association established by the (N)-layer between two or more (N+1) entities
for the transfer of data. [ISO 7498]
(N)-connection-endpoint: Terminator at one end of an (N)-connection within an (N)-service-
access-point. [ISO 7498]
(N)-connection-endpoint-identifier: Identifier of an (N)-connection-endpoint which can be
used to identify the corresponding (N)-connection at an (N)-service-access-point. [ISO 7498]
connection-mode (CO): Connection-mode in which data are transmitted after the
establishment of a communication path. [IEC 60870-6-2]
NOTE – The connection-mode provides a context within which successive data units are related, making it possible
to maintain sequence and provide flow-control.
connection-mode network service (CO-NS): Service providing a connection-oriented
service for the transfer of transport-protocol-data-units between network-service-access-
points supported by the network layer.
connection-mode transport service (CO-TS): Service providing a connection-oriented
service for the transfer of session-protocol-data-units between transport-service-access-
points supported by the transport layer.
connectionless-mode (CL): Mode in which data are transmitted in a single self-contained
entity containing sufficient information to be routed to the destination without the need for call
establishment and without requiring any kind of network acknowledgement or return packet.
[IEC 60870-6-2]
connectionless-mode network service (CL-NS): Service providing a connectionless-mode
service for the transfer of transport-protocol-data-units between network-service-access-
points supported by the network layer.
connectionless-mode transport service (CL-TS): Service providing a connectionless-mode
service for the transfer of session-protocol-data-units between transport service-access-points
supported by the transport layer.
control: Purposeful action on or in a system to meet specified objectives. [IEV 351-01-04]
NOTE – Control may include monitoring and safeguarding in addition to the control action itself.
control centre: Location where a master controlling station is located. [IEV 371-06-13]
[IEC 60050-371:1984, 371-06-13, modified – "master station" replaced with "controlling
station"]
control direction: Direction of transmission from a controlling station to a controlled station.
[IEC 60870-5-5 and IEC 60870-5-101]
control discrepancy switch; control discrepancy key: Discrepancy switch or key with
additional command functions.
NOTE – The switch is usually of the self-return type. The command function is activated by moving the switch into
an unstable position.
control lines: All lines at an interface used for control, signalling and measurement purposes.
control-field: Data field in a protocol data unit that contains information on the functional use
of the data unit.
controlled station: See outstation RTU
controlling station: See master station Station which performs the telecontrol of outstations
or controlled stations
counted measurand; metered measurand; metered reading: Process variable which is
measured by totalizing increments.
counter pulse; meter pulse: Pulse representing one incremental unit.
chronological transmission of change-of-state information: See transmission of
change-of-state information chronologically
cross-talk: Phenomenon in which a signal transmitted on one circuit or channel of a
transmission system creates an undesired effect on another circuit of channel.
cycle time: Time interval between consecutive appearances of any information that is
transmitted periodically. [IEV 371-08-19]
cyclic transmission: Transmission method in which the message sources are scanned and
messages are transmitted cyclically according to a definite sequence. [IEV 371-07-01]
data circuit: Pair of associated transmit and receive channels that provides a means of two-
way data communication. [ISO 2382-9]
NOTES
1 Between data switching exchanges, the data circuit may or may not include data circuit-terminating
equipment (DCE), depending on the type of interface used at the data switching exchange.
2 Between a data station and a data switching exchange or data concentrator, the data circuit includes the
data circuit-terminating equipment at the data station end, and may include equipment similar to a DCE at the
data switching exchange or data concentrator location.
data circuit terminating equipment (DCE); line coupler: Interfacing equipment sometimes
required to couple the DTE (data terminal equipment) with a transmission circuit or channel.
data consistency: Measure of conformity of information on variables at different locations in
different instants.
data integrity: Ability of a communication system to deliver data from its originator to its
destination with an acceptable residual error rate.
data lifetime control: See messages lifetime control
data network: Arrangement of data circuits and switching facilities for establishing
connections between data terminal equipment. [ISO 2382-9]
data security: Procedures and actions designed to prevent the unauthorized disclosure,
transfer, modification or destruction, whether accidental or intentional, of data.
data size: Field length of a specified data type in bits. [IEC 60870-5-4]
data terminal equipment (DTE): Functional unit of a data station that serves as a data
source or a data sink and provides for the data communication control function to be
performed in accordance with a protocol.
data transfer phase: That phase of a call during which user data may be transferred between
data terminal equipment that are interconnected via the network. [ISO 2382-9]
data transfer rate: Average number of bits, characters or blocks per unit time passing
between corresponding equipment in a data transmission system. [ISO 2382-9]
data transfer time: Time that elapses between the initial offering of a unit of user data to a
network by transmitting data terminal equipment and the complete delivery of that to receiving
data terminal equipment.
data transmission channel: Means of one-way transmission. [ISO 2382-9]
NOTE – A channel may be provided, for example, by frequency or time division multiplexing.
data transport functions; data transport services: All functions involved in the
management of information transfer between stations.
decision feedback, transmission with: See transmission with decision feedback.
data type : Defined method of data presentation. For example: data type INTEGER for whole
numbers or data type OCTET STRING for an assembly of octets. [IEC 60870-5-4]
data unit: Information entity that has a common cause of transmission. [IEC 60870-5-3]
data unit type: Information field in the beginning of an application data unit that identifies the
type and the length of data unit, and implicitly or explicitly specifies the structure of the
application data unit and the structure, type and number of information objects. [IEC 60870-5-3]
(N)-data-source: (N)-entity that sends (N-1)-service-data-units on an (N-1)-connection.
[ISO 7498]
datagram: In packet switching, self-contained packet, independent of other packets that
carries information sufficient for routing from the originating data terminal equipment (DTE) to
the destination DTE, without relying on earlier exchanges between the DTEs and the network.
[ISO 2382-9]
datagram service: Service that routes a datagram to the destination identified in its address
field without reference by the network to any other datagram. [ISO 2382-9]
NOTE – Datagrams may be delivered to the destination in a different order from that in which they were entered in
the network.
deblocking: Function performed by an (N)-entity to identify multiple (N)-service data-units
which are contained in one (N)-protocol-data-unit. It is the reverse function of blocking.
[ISO 7498]
decode: Reversing of coding to obtain original information.
decryption, decipherment: Reversal of a corresponding reverse encipherment. [ISO 7498-2]
dedicated circuit: Direct non-switched circuit (modified only by the network management).
demultiplexing (in OSI sense): Function performed by an (N)-entity which identifies (N)-
protocol-data-units for more than one (N)-connection within (N-1)-service-data-units received
on a single (N-1)-connection. It is the reverse function of the multiplexing function performed
by the (N)-entity sending the (N-1)-service-data-unit. [ISO 7498]
differential mode voltage: Voltage between two active conductors.
differential phase-shift keying (DPSK): Method of modulation employed for digital
transmission. In DPSK, each signal element is a change in the phase of the carrier with
respect to its previous phase angle.
digital data circuit: Circuit provided through a circuit switched data network (CSDN) or
through a concatenation of circuit switched data networks (CSDN), and may be switched or
permanent.
NOTE – Some ISDNs or pre-ISDNs provide circuit switched services through an X.21 interface. Those services are
equivalent to those provided by a CSDN.
digital measured value: Digital representation of a measured value.
digital pulse duration modulation (DPDM): Modulation method in which the binary signal
elements "0" and "1" are represented by pulses or pulse intervals of different duration.
[IEV 371-07-11]
NOTE – The ratio between the long and the short signal element duration, which depends on requirements of
reliability and speed of the message transmission, is not necessarily an integer.
discrepancy switch: Switch with optical position indication used to display two distinct states
of operational equipment.
discrimination: See separating capability
dispatching centre; load dispatching centre: Centre for the control of an operational
network for generation and/or distribution of electrical energy.
double command: Pair of commands each of which is used to cause operational equipment
to change to one of two determined states. [IEV 371-03-03]
double-point information: Monitored information represented by two bits characterizing two
determined states and two indeterminate states of operational equipment. [IEV 371-02-08]
Example: 10, 01 represent determined states
00, 11 represent indeterminate states
down time: Time interval during which an item is in a down state. [IEV 191-09-08]
duplex transmission; duplex traffic: Data transmission in both directions at the same time.
[ISO 2382-9]
dynamic conformance requirements: One of the requirements that specify what observable
behaviour is permitted by the relevant OSI International Standard(s) or ITU-T Recommendations
in instances of communication. [ISO/IEC 9646-1]
echo principle: See transmission with information feedback
electric power systems messaging (EPSM): Method to exchange telecontrol data within
electric power control systems.
encryption; encipherment: Cryptographic transformation of data to produce ciphertext.
[ISO 7498-2]
end system: Term taken from the OSI reference model terminology and used to refer to the
functionality of the communicating system in an abstract form, independent of the physical
realization. An end system in real world terminology may, therefore, as an example, be either
a simple self-contained system or a group of interconnected main frame computers acting as
a whole. All end systems contain a transport layer entity function.
enhanced performance architecture (EPA): Protocol reference model that provides,
compared with the full seven-layer architecture according to the Basic Reference Model
(ISO 7498) a three-layer architecture for obtaining faster response times for time critical
information, but with service limitations. [IEC 60870-5-5]
envelope: Group of binary digits formed by an n-bit byte augmented by a number of
additional bits which are required for the operation of the data network. [IEV 721-19-25]
EPA: See enhanced performance architecture
EPSM: See electric power systems messaging
equipment failure information: Information indicating failure of telecontrol equipment.
[IEV 371-04-10]
error burst: Limited sequence of bits in which the bit error rate is significantly higher than the
average bit error rate
error control: That part of a protocol controlling the detection, and possibly the corrections,
of errors. [ISO 2382-9]
error detecting code: Code which conforms to specific rules of construction so that, if errors
o
...

RAPPORT CEI
TECHNIQUE
IEC
60870-1-3
TECHNICAL
Deuxième édition
REPORT
Second edition
1997-04
Matériels et systèmes de téléconduite –
Partie 1:
Considérations générales –
Section 3: Glossaire
Telecontrol equipment and systems –
Part 1:
General considerations –
Section 3: Glossary
Numéro de référence
Reference number
CEI/IEC 60870-1-3: 1997
Validité de la présente publication Validity of this publication
Le contenu technique des publications de la CEI est cons- The technical content of IEC publications is kept under
tamment revu par la CEI afin qu'il reflète l'état actuel de constant review by the IEC, thus ensuring that the content
la technique. reflects current technology.
Des renseignements relatifs à la date de reconfirmation de Information relating to the date of the reconfirmation of the
la publication sont disponibles auprès du Bureau Central de publication is available from the IEC Central Office.
la CEI.
Les renseignements relatifs à ces révisions, à l'établis- Information on the revision work, the issue of revised
sement des éditions révisées et aux amendements peuvent editions and amendments may be obtained from IEC
être obtenus auprès des Comités nationaux de la CEI et National Committees and from the following IEC
dans les documents ci-dessous: sources:
• Bulletin de la CEI • IEC Bulletin
• Annuaire de la CEI • IEC Yearbook
Publié annuellement Published yearly
• Catalogue des publications de la CEI • Catalogue of IEC publications
Publié annuellement et mis à jour régulièrement Published yearly with regular updates
Terminologie Terminology
En ce qui concerne la terminologie générale, le lecteur se For general terminology, readers are referred to IEC 50:
reportera à la CEI 50: Vocabulaire Electrotechnique Inter- International Electrotechnical Vocabulary (IEV), which is
national (VEI), qui se présente sous forme de chapitres issued in the form of separate chapters each dealing
séparés traitant chacun d'un sujet défini. Des détails with a specific field. Full details of the IEV will be
complets sur le VEI peuvent être obtenus sur demande. supplied on request. See also the IEC Multilingual
Voir également le dictionnaire multilingue de la CEI. Dictionary.
Les termes et définitions figurant dans la présente publi- The terms and definitions contained in the present publi-
cation ont été soit tirés du VEI, soit spécifiquement cation have either been taken from the IEV or have been
approuvés aux fins de cette publication. specifically approved for the purpose of this publication.
Symboles graphiques et littéraux Graphical and letter symbols
Pour les symboles graphiques, les symboles littéraux et les For graphical symbols, and letter symbols and signs
signes d'usage général approuvés par la CEI, le lecteur approved by the IEC for general use, readers are referred to
consultera: publications:
– la CEI 27: Symboles littéraux à utiliser en – IEC 27: Letter symbols to be used in electrical
électro-technique; technology;
– la CEI 417: Symboles graphiques utilisables – IEC 417: Graphical symbols for use on
sur le matériel. Index, relevé et compilation des equipment. Index, survey and compilation of the
feuilles individuelles; single sheets;
– la CEI 617: Symboles graphiques pour schémas; – IEC 617: Graphical symbols for diagrams;
et pour les appareils électromédicaux, and for medical electrical equipment,
– la CEI 878: Symboles graphiques pour – IEC 878: Graphical symbols for electromedical
équipements électriques en pratique médicale. equipment in medical practice.
Les symboles et signes contenus dans la présente publi- The symbols and signs contained in the present publication
cation ont été soit tirés de la CEI 27, de la CEI 417, de la have either been taken from IEC 27, IEC 417, IEC 617
CEI 617 et/ou de la CEI 878, soit spécifiquement approuvés and/or IEC 878, or have been specifically approved for the
aux fins de cette publication. purpose of this publication.
Publications de la CEI établies par le IEC publications prepared by the same
même comité d'études technical committee
L'attention du lecteur est attirée sur les listes figurant à la fin The attention of readers is drawn to the end pages of this
de cette publication, qui énumèrent les publications de la publication which list the IEC publications issued by the
CEI préparées par le comité d'études qui a établi la technical committee which has prepared the present
présente publication. publication.

RAPPORT
CEI
TECHNIQUE – TYPE 3
IEC
60870-1-3
TECHNICAL
Deuxième édition
REPORT – TYPE 3
Second edition
1997-04
Matériels et systèmes de téléconduite –
Partie 1:
Considérations générales –
Section 3: Glossaire
Telecontrol equipment and systems –
Part 1:
General considerations –
Section 3: Glossary
 IEC 1997 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni utilisée No part of this publication may be reproduced or utilized in
sous quelque forme que ce soit et par aucun procédé, électronique any form or by any means, electronic or mechanical, including
ou mécanique, y compris la photocopie et les microfilms, sans photocopying and microfilm, without permission in writing from
l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE W
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue

– 2 – 60870-1-3 © CEI: 1997
SOMMAIRE
Pages
AVANT-PROPOS. 4
INTRODUCTION. 8
Articles
1 Domaine d'application . 10
2 Documents de référence. 10
3 Définitions. 14 à 74

60870-1-3 © IEC: 1997 – 3 –
CONTENTS
Page
FOREWORD . 5
INTRODUCTION . 9
Clause
1 Scope and object . 11
2 Reference documents . 11
3 Definitions. 15 to 75

– 4 – 60870-1-3 © CEI: 1997
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
–––––––––
MATÉRIELS ET SYSTÈMES DE TÉLÉCONDUITE –
Partie 1: Considérations générales –
Section 3: Glossaire
AVANT-PROPOS
1) La CEI (Commission Electrotechnique Internationale) est une organisation mondiale de normalisation composée
de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a pour objet de
favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines de
l'électricité et de l'électronique. A cet effet, la CEI, entre autres activités, publie des Normes Internationales.
Leur élaboration est confiée à des comités d'études, aux travaux desquels tout Comité national intéressé par le
sujet traité peut participer. Les organisations internationales, gouvernementales et non gouvernementales, en
liaison avec la CEI, participent également aux travaux. La CEI collabore étroitement avec l'Organisation
Internationale de Normalisation (ISO), selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques, représentent, dans la mesure
du possible un accord international sur les sujets étudiés, étant donné que les Comités nationaux intéressés
sont représentés dans chaque comité d’études.
3) Les documents produits se présentent sous la forme de recommandations internationales. Ils sont publiés
comme normes, rapports techniques ou guides et agréés comme tels par les Comités nationaux.
4) Dans le but d'encourager l'unification internationale, les Comités nationaux de la CEI s'engagent à appliquer de
façon transparente, dans toute la mesure possible, les Normes Internationales de la CEI dans leurs normes
nationales et régionales. Toute divergence entre la norme de la CEI et la norme nationale correspondante doit
être indiquée en termes clairs dans cette dernière.
5) La CEI n’a fixé aucune procédure concernant le marquage comme indication d’approbation et sa responsabilité
n’est pas engagée quand un matériel est déclaré conforme à l’une de ses normes.
6) L’attention est attirée sur le fait que certains des éléments de la présente Norme internationale peuvent faire
l’objet de droits de propriété intellectuelle ou de droits analogues. La CEI ne saurait être tenue pour
responsable de ne pas avoir identifié de tels droits de propriété et de ne pas avoir signalé leur existence.
La tâche principale des comités d’études de la CEI est d’élaborer des Normes internationales.
Exceptionnellement, un comité d’études peut proposer la publication d’un rapport technique de
l’un des types suivants:
• type 1, lorsque, en dépit de maints efforts, l’accord requis ne peut être réalisé en faveur
de la publication d’une Norme internationale;
• type 2, lorsque le sujet en question est encore en cours de développement technique
ou lorsque, pour une raison quelconque, la possibilité d’un accord pour la publication
d’une Norme internationale peut être envisagée pour l’avenir mais pas dans l’immédiat;
• type 3, lorsqu’un comité d’études a réuni des données de nature différente de celles qui
sont normalement publiées comme Normes internationales, cela pouvant comprendre, par
exemple, des informations sur l’état de la technique.
Les rapports techniques des types 1 et 2 font l’objet d’un nouvel examen trois ans au plus tard
après leur publication afin de décider éventuellement de leur transformation en Normes
internationales. Les rapports techniques du type 3 ne doivent pas nécessairement être révisés
avant que les données qu’ils contiennent ne soient plus jugées valables ou utiles.

60870-1-3 © IEC: 1997 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
––––––––
TELECONTROL EQUIPMENT AND SYSTEMS –
Part 1: General considerations –
Section 3: Glossary
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
report of one of the following types:
• type 1, when the required support cannot be obtained for the publication of an
International Standard, despite repeated efforts;
• type 2, when the subject is still under technical development or where for any other
reason there is the future but no immediate possibility of an agreement on an International
Standard;
• type 3, when a technical committee has collected data of a different kind from that
which is normally published as an International Standard, for example "state of the art".
Technical reports of types 1 and 2 are subject to review within three years of publication to
decide whether they can be transformed into International Standards. Technical reports of
type 3 do not necessarily have to be reviewed until the data they provide are considered to be
no longer valid or useful.
– 6 – 60870-1-3 © CEI: 1997
La CEI 60870-1-3, rapport technique de type 3, a été établie par le comité d’études 57 de la
CEI: Conduite des systèmes de puissance et communications associées.
Cette deuxième édition annule et remplace la première édition parue en 1990, dont elle
constitue une révision technique.
Le texte de ce rapport technique est issu des documents suivants:
Projet de comité Rapport de vote
57(Sec)171 57/297/RVC
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de ce rapport technique.

60870-1-3 © IEC: 1997 – 7 –
IEC 60870-1-3, which is a technical report of type 3, has been prepared by IEC technical
committee 57: Power system control and associated communications.
This second edition cancels and replaces the first edition published in 1990 and constitutes a
technical revision.
The text of this technical report is based on the following documents:
Committee draft Report on voting
57(Sec)171 57/297/RVC
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.

– 8 – 60870-1-3 © CEI: 1997
INTRODUCTION
Les normes et les rapports concernant la téléconduite des équipements et des systèmes
produits pendant les dernières années par le comité technique 57 de la CEI dans différents
documents des séries CEI 60870-5 et CEI 60870-6 utilisent un certain nombre de termes avec
une acception spécifique dans les applications de téléconduite qui ne sont pas encore définis
dans la CEI 60050(371): Vocabulaire Electrotechnique International (VEI), Chapitre 371:
Téléconduite (1984). Dans la plupart des documents de la série 60870 il y a déjà des
glossaires relatifs aux documents. Cependant, la mise en commun de tous ces termes dans le
présent document est utile pour le lecteur des documents mentionnés ci-dessus.
Cette section de la CEI 60870-1 présente, en suivant l’ordre alphabétique de la version
anglaise, ces termes et définitions. Elle donne aussi un accès général de référence à des
termes ayant une signification particulière dans le domaine des systèmes et équipements de
téléconduite et qu'il conviendrait d'utiliser dans les futures documentations.

60870-1-3 © IEC: 1997 – 9 –
INTRODUCTION
Standards and reports on telecontrol equipment and systems produced during the last few
years by IEC technical committee 57 in different documents of series IEC 60870-5 and
IEC 60870-6 use a certain number of terms with specific meanings in telecontrol applications
that are not yet defined in IEC 60050(371): International Electrotechnical Vocabulary (IEV) –
Chapter 371: Telecontrol (1984). In most of the documents of the 60870 series, glossaries
related to the particular document already exist. Nevertheless, the collection of relevant terms
in this document is useful for the reader of the above-mentioned documents.
This section of IEC 60870-1 presents in alphabetic order these terms and their definitions. It
also presents a comprehensive means of referring to terms with particular meaning in
telecontrol systems and equipment that should also be used in future telecontrol
documentation.
– 10 – 60870-1-3 © CEI: 1997
MATÉRIELS ET SYSTÈMES DE TÉLÉCONDUITE –
Partie 1: Considérations générales –
Section 3: Glossaire
1 Domaine d'application
Cette série de normes s'applique aux équipements et systèmes de téléconduite utilisant une
transmission digitale codée série des données, pour la commande et le contrôle de processus
géographiquement dispersés.
Dans cette section de la CEI 60870-1 sont inclus les termes qui s'appliquent spécifiquement
aux techniques de téléconduite ainsi que d'autres termes nécessaires à la compréhension des
normes relative à la téléconduite.
Ce rapport fournit aussi, s'il y a lieu, des références à d'autres dictionnaires d'électricité et
d'électronique.
Les termes considérés comme étant bien connus des lecteurs de normes de téléconduite ne
sont pas inclus dans ce rapport. Cela s'applique en particulier au domaine des communications
où des termes comme, par exemple, «information» et «bit» sont courants et bien compris.
Tous les termes sont cités dans l'ordre alphabétique anglais.
2 Documents de référence
Les normes suivantes contiennent des clauses qui, à travers leurs références mentionnées
dans ce texte, constituent les clauses relatives aux publications des séries de normes
CEI 60870. Au moment où cette présente publication est faite, les éditions de référence sont
bonnes. Le lecteur est encouragé à rechercher dans le futur, en cas de révision, la norme
actualisée correspondante. La CEI et l'ISO tiennent à jour leurs listes de normes
opérationnelles.
CEI 60050(191): 1990,
Vocabulaire Electrotechnique International (VEI) – Chapitre 191: Sûreté
de fonctionnement et qualité de service
CEI 60050(351): 1997, Vocabulaire Electrotechnique International (VEI) – Chapitre 351:
Commande et régulation automatiques
CEI 60050(371): 1984, Vocabulaire Electrotechnique International (VEI) – Chapitre 371:
Téléconduite
CEI 60050(721): 1992, Vocabulaire Electrotechnique International (VEI) – Chapitre 721:
Télégraphie, télécopie et communication de données
CEI 60870-1-4: 1994, Matériels et systèmes de téléconduite – Partie 1: Considérations générales
– Section 4: Aspects fondamentaux de la transmission de données de téléconduite et
organisation des normes CEI 60870-5 et CEI 60870-6
CEI 60870-2-1: 1995, Matériels et systèmes de téléconduite – Partie 2: Conditions de
fonctionnement – Section 1: Alimentation et compatibilité électromagnétique
CEI 60870-5-3: 1992, Matériels et systèmes de téléconduite – Partie 5: Protocoles de
transmission – Section 3: Structure générale des données d’application

60870-1-3 © IEC: 1997 – 11 –
TELECONTROL EQUIPMENT AND SYSTEMS –
Part 1: General considerations –
Section 3: Glossary
1 Scope and object
This technical report applies to telecontrol equipment and systems with coded bit serial data
transmission for monitoring and control of geographically widespread processes.
This section of IEC 60870-1 covers those terms which are specifically relevant to telecontrol
techniques as well as other terms which are necessary for the understanding of telecontrol
standards.
This report also gives, where applicable, references to other dictionaries of electrical and
electronic terms.
Terms which are considered to be well known by readers of telecontrol standards are not
included in this report. This applies particularly in the field of communications where such
terms as, for example, "information" and "bit" are commonplace and well understood.
2 Reference documents
The following standards contain provisions which, through reference in this text, constitute
provisions of this section of the IEC 60870 series. At the time of publication, the editions of the
reference documents indicated were valid. All standards are subject to revision, so readers are
encouraged to investigate the possibility of applying the most recent editions of the standards
indicated below. Members of IEC and ISO maintain registers of currently valid International
Standards.
IEC 60050(191): 1990, International Electrotechnical Vocabulary (IEV) – Chapter 191:
Dependability and quality of service
IEC 60050(351): 1997, International Electrotechnical Vocabulary (IEV) – Chapter 351:
Automatic control
IEC 60050(371): 1984, International Electrotechnical Vocabulary (IEV) – Chapter 371:
Telecontrol
IEC 60050(721): 1992, International Electrotechnical Vocabulary (IEV) – Chapter 721:
Telegraphy, facsimile and data communication
IEC 60870-1-4: 1994, Telecontrol equipment and systems – Part 1: General considerations –
Section 4: Basic aspects of telecontrol data transmission and organization of standards
IEC 60870-5 and IEC 60870-6
IEC 60870-2-1: 1995, Telecontrol equipment and systems – Part 2: Operating conditions –
Section 1: Power supply and electromagnetic compatibility
IEC 60870-5-3: 1992, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 3: General structure of application data

– 12 – 60870-1-3 © CEI: 1997
CEI 60870-5-4: 1993, Matériels et systèmes de téléconduite – Partie 5: Protocoles de
transmission – Section 4: Définitions et codages des éléments d’information d’application
CEI 60870-5-5: 1995, Matériels et systèmes de téléconduite – Partie 5: Protocoles de
transmission – Section 5: Fonctions d’application de base
CEI 60870-5-101: 1995, Matériels et systèmes de téléconduite – Partie 5: Protocoles de
transmission – Section 101: Norme d’accompagnement pour les tâches élémentaires de
téléconduite
CEI 60870-6-501: 1995, Matériels et systèmes de téléconduite – Partie 6: Protocoles de
téléconduite compatibles avec les normes ISO et les recommandations de l'UIT-T – Section
501: Définitions des services TASE.1
CEI 60870-6-502: 1995, Matériels et systèmes de téléconduite – Partie 6: Protocoles de
téléconduite compatibles avec les normes ISO et les recommandations de l'UIT-T – Section 502:
Définitions du protocole TASE.1
ISO/IEC 2382-9: 1995, Traitement de l'information – Vocabulaire – Partie 9: Communication de
données
ISO/IEC 3309: 1993, Technologies de l'information – Télécommunications et échange
d'information entre systèmes – Procédures de commande de liaison de données à haut niveau
(HDLC) – Structure de trame
ISO/IEC 4335: 1993, Technologies de l'information – Télécommunications et échange
d'informations entre systèmes – Procédures de commande de liaison de données à haut
niveau (HDLC) – Eléments de procédures
ISO 7498-1: 1994, Technologies de l'information – Interconnexion des systèmes ouverts (OSI) –
Modèle de référence de base: le modèle de base
ISO 7498-2: 1989, Systèmes de traitement de l'information – Interconnexion des systèmes
ouverts – Modèle de référence de base – Partie 2: Architecture de sécurité
ISO 8326: 1987, Systèmes de traitement de l'information – Interconnexion de systèmes ouverts –
Service de session en mode connexion
ISO TR 8509: 1987, Systèmes de traitement de l'information – Interconnexion de systèmes
ouverts – Conventions de service
ISO 8648: 1988, Systèmes de traitement de l'information – Interconnexion de systèmes ouverts –
Organisation interne de la Couche Réseau
ISO/IEC 8824: 1990, Technologies de l'information – Interconnexion de systèmes ouverts –
Spécification de la notation de syntaxe abstraite numéro 1 (ASN.1)
ISO/IEC 9545: 1994, Technologies de l'information – Interconnexion de systèmes ouverts
(OSI) – Structure de la couche Application
ISO/IEC 9646-1: 1994, Technologies de l'information – Interconnexion de systèmes ouverts –
Cadre général et méthodologie des tests de conformité – Partie 1: Concepts généraux
ISO/IEC TR 10000-1: 1995, Technologies de l'information – Cadre et taxonomie des profils
internationaux normalisés – Partie 1: Principes généraux et cadre de documentation
ISO/IEC TR 10000-2: 1995, Technologies de l'information – Cadre et taxonomie des profils
internationaux normalisés – Partie 2: Principes et taxonomie pour profils OSI
UIT-T X.15: 1984, Définition de termes concernant les réseaux publics de données

60870-1-3 © IEC: 1997 – 13 –
IEC 60870-5-4: 1993, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 4: Definition and coding of application information elements
IEC 60870-5-5: 1995, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 5: Basic application functions
IEC 60870-5-101: 1995, Telecontrol equipment and systems – Part 5: Transmission protocols –
Section 101: Companion standard for basic telecontrol tasks
IEC 60870-6-501: 1995, Telecontrol equipment and systems – Part 6: Telecontrol protocols
compatible with ISO standards and ITU-T recommendations – Section 501: TASE.1 Service
definitions
IEC 60870-6-502: 1995, Telecontrol equipment and systems – Part 6: Telecontrol protocols
compatible with ISO standards and ITU-T recommendations – Section 502: TASE.1 Protocol
definitions
ISO/IEC 2382-9: 1995, Information technology – Vocabulary – Part 9: Data communication
ISO/IEC 3309: 1993, Information technology – Telecommunications and information exchange
between systems – High-level data link control (HDLC) procedures – Frame structure
ISO/IEC 4335: 1993, Information technology – Telecommunications and information exchange
between systems – High-level data link control (HDLC) procedures – Elements of procedures
ISO 7498-1: 1994, Information technology – Open Systems Interconnection – Basic Reference
Model: The Basic Model
ISO 7498-2: 1989, Information processing systems – Open Systems Interconnection – Basic
Reference Model – Part 2: Security Architecture
ISO 8326: 1987, Information processing systems – Open Systems Interconnection – Basic
connection oriented session service definition
ISO TR 8509: 1987, Information processing systems – Open Systems Interconnection –
Service conventions
ISO 8648: 1988, Information processing systems – Open Systems Interconnection – Internal
organization of the Network Layer
ISO/IEC 8824: 1990, Information technology – Open Systems Interconnection – Specification
of Abstract Syntax Notation One (ASN.1)
ISO/IEC 9545: 1994, Information technology – Open Systems Interconnection – Application
Layer structure
ISO/IEC 9646-1: 1994, Information technology – Open Systems Interconnection – Conformance
testing methodology and framework – Part 1: General concepts
ISO/IEC TR 10000-1: 1995, Information technology – Framework and taxonomy of International
Standarized Profiles – Part 1: General principles and documentation
ISO/IEC TR 10000-2: 1995, Information technology – Framework and taxonomy of International
Standarized Profiles – Part 2: Principles and Taxonomy for OSI Profiles
ITU-T X.15: 1984, Definition of terms concerning public data networks

– 14 – 60870-1-3 © CEI: 1997
3 Définitions
transmission chronologique absolue; chronologie absolue: Mode de transmission des
changements d'état tel que l'information transmise est accompagnée de données
chronologiques indiquant l'instant exact des changements d'état, dans les limites du temps de
résolution. [VEI 371-05-02]
accusé de réception: Voir «positive acknowledgement».
temps d'acquisition: Durée minimale nécessaire à la détection et prise en compte correcte
d'un changement d'état.
adresse: Partie d'un message identifiant sa source ou sa destination.
commande de position: Commande qui provoque un changement d'état d'un organe pouvant
prendre plus de deux états. [VEI 371-03-10]
alarme: Information ayant pour but d'attirer l'attention sur un état anormal.
NOTE – La transition d'un état normal à un état anormal provoque un avertissement visuel et/ou sonore, qui doit
faire l'objet d'un accusé de réception. La transition d'un état anormal à un état normal provoque en général un
changement d'indication et, dans certaines applications, également un avertissement sonore et/ou visuel, qui
doit faire l'objet d'un accusé de réception.
signal analogique: Signal se présentant sous la forme d'une grandeur variant de manière
continue.
association d'applications: Relation coopérative entre deux invocations d'entité application
(application-services objects-invocations) pour contrôler l'utilisation du service de présentation
en vue d'échanger des informations et de coordonner leurs actions conjointes. [ISO/IEC 9545]
entité application (AE): Aspects d'un processus d'application concernant l'Interconnexion des
Systèmes Ouverts (OSI). [ISO 7498]
fonctions d'application: Fonctions couvrant les besoins spécifiques du processus auquel est
appliqué un système de téléconduite ou un SCADA.
Les fonctions d'application sont divisées en fonctions de base et fonctions de traitement
étendues.
fonction d'application (au sens du modèle de référence): Parties des processus
d'application qui exécutent les procédures de communication entre les processus d'application.
[ISO 7498]
processus d'application: Elément dans un système ouvert réel qui réalise le traitement de
l'information pour une application particulière. [ISO 7498]
profil d'une application: Profil définissant l'usage de protocoles normalisés de l'Interconnexion
des Systèmes Ouverts (OSI), couches 5 à 7, pour fournir un transfert structuré d'information
entre systèmes.
élément de service d'application: Partie d'une entité application (AE) qui fournit les moyens
définis dans un environnement «Interconnexion des Systèmes Ouverts (OSI)», en utilisant,
quand ils s'appliquent, les services sous-jacents. [ISO 7498]

60870-1-3 © IEC: 1997 – 15 –
3 Definitions
absolute chronology; time tagging: Method of transmission of changes-of-state so that
transmitted information is accompanied by data giving the registered time at which the change
occurred, within the time resolution. [IEV 371-05-02]
acknowledgement: See positive acknowledgement; negative acknowledgement
acquisition time: Minimum time for correct detection and processing of a change-of-state.
address: Part of a message identifying the source or its destination.
adjusting command: Command used to change the state of operational equipment having
more than two states. [IEV 371-03-10]
alarm: Information for attracting attention to some abnormal state.
NOTE – A transition from a normal into an abnormal state causes a visual and/or audible warning which has to
be acknowledged. A transition from an abnormal into a normal state usually causes a change of indication and,
in some applications, also causes a visual and/or audible warning which has to be acknowledged.
analogue signal: Signal in the form of a continuously variable value.
application association: Co-operative relationship between two application-service-object-
invocations which govern their bilateral use of the Presentation Service for communication of
information and co-ordination of their joint operation. [ISO/IEC 9545]
application entity (AE): Aspects of an application-process pertinent to Open Systems
Interconnection (OSI). [ISO 7498]
application functions: Functions covering the special needs of the process to which a
telecontrol or SCADA system is applied.
The application functions are divided into basic functions and extended processing functions.
application functions (in the sense of the basic reference model): Part of application-
processes which performs the remote communications procedures between application-
processes. [ISO 7498]
application-process: Element within a real open system which performs the information pro-
cessing for a particular application. [ISO 7498]
application profile: Profile defining the use of protocol standards from Open Systems
Interconnection (OSI) layers 5 to 7, to provide for the structured transfer of information
between systems.
application service element: That part of an application-entity which provides an Open
Systems Interconnection (OSI) environment capability, using underlying services when
appropriate. [ISO 7498]
– 16 – 60870-1-3 © CEI: 1997
élément de service de contrôle d'association: Elément de service d'application qui fournit
un moyen unique pour établir et terminer toutes les associations d'applications. [ISO/IEC 9545]
transmission de téléconduite arythmique: Voir «start-stop telecontrol transmission»
transmission arythmique: Transmission de données dans laquelle le signal de départ de
chaque caractère ou bloc de caractères survient à un instant quelconque, mais ou, après ce
démarrage, chacun des éléments de signal du caractère ou du bloc survient en relation de
phase constante avec les instants significatifs d'une base de temps fixe. [ISO 2382-9]
commande automatique de production (AGC): Voir «load frequency control».
information auxiliaire: Information utilisée pour le contrôle du fonctionnement d'un système
de téléconduite.
disponibilité: Aptitude d'une unité ou d'un système à réaliser les fonctions qui lui sont
demandées à n'importe quel moment.
temps moyen de transfert: Moyenne des temps de transfert dans tous les cas de
présentation du signal primaire au système de téléconduite. [VEI 371-08-18]
circuit symétrique; ligne symétrique; paire de signaux symétriques: Ligne de transmission
composée de deux conducteurs et d'une masse, pouvant être exploitée de telle sorte que,
lorsque les tensions des deux conducteurs en chaque point de la ligne sont égales en valeur et
opposées en polarité par rapport à la terre, les courants des deux conducteurs sont de valeur
égale et de sens opposé.
transmission symétrique: Méthode de transmission où chaque équipement terminal (DTE) de
deux stations interconnectées peut initialiser à tout moment la transmission d'un message.
[CEI 60870-1-4]
dispositif d'isolement: Dispositif assurant un isolement galvanique entre les matériels de
téléconduite et les matériels d'exploitation (par exemple relais, opto-coupleurs ou transformateurs).
norme de base: Norme internationale, rapport technique (TR) ou recommandation de l'UIT-T
utilisés dans la définition d'un Profil. [ISO/IEC TR 10000-1]
fonction d'application de base (en téléconduite): Procédure de transmission qui réalise une
fonction de supervision ou de conduite qui est utilisée en général dans les systèmes de
téléconduite. [CEI 60870-5-5]
Exemples: transmission de commandes, transmission d’événements, transmissions cycliques, etc.
fonctions de base: Fonctions de base gérant tous les types d'informations individuelles
provenant des – et destinées aux – matériels d'exploitation et de l'opérateur.
modèle de référence de base: Voir «open system interconnection».
baud (Bd): Unité de rapidité de modulation ou de débit d'éléments de signal de durée
constante dans un signal temporel discret ou un signal numérique; le nombre de bauds est
égal à l'inverse de la durée en secondes du plus court élément de signal ou de l'intervalle
unitaire dans un signal numérique composé d'éléments de signal de durée constante.
[VEI 721-03-27]
NOTE – Par exemple, si la durée de l'intervalle unitaire est de 20 ms, la rapidité de modulation est de 50 Bd.

60870-1-3 © IEC: 1997 – 17 –
association control service element: Application service element that provides the exclusive
means for establishing and terminating all application-associations. [ISO/IEC 9545]
asynchronous telecontrol transmission: See start-stop telecontrol transmission.
asynchronous transmission: Data transmission in which the time of occurrence of the start of
each character or block of characters is arbitrary; once started, the time of occurrence of each
signal representing a bit within the character or block, has the same relationship to significant
instants of a fixed time base. [ISO 2382-9]
automatic generation control (AGC): See load-frequency control.
auxiliary information: Information used in order to control the operation of a telecontrol
system.
availability: Ability of a unit or system to perform its required function at any given moment.
average transfer time: Average of the transfer time for every case of input of the primary
signal with respect to the telecontrol system. [IEV 371-08-18]
balanced circuit; balanced line; balanced signal pair: Transmission line consisting of two
conductors in the presence of ground, capable of being operated in such a way that, when the
voltages of the two conductors at all transverse planes are equal in magnitude and opposite in
polarity with respect to ground, the currents in the two conductors are equal in magnitude and
opposite in direction.
balanced transmission: Transmission method by which either Data Terminal Equipment (DTE)
of two connected stations may initiate a message transmission at any time. [IEC 60870-1-4]
barrier device: Device for galvanic isolation of telecontrol equipment and the operational
equipment (e.g. a relay, optocoupler or transformer).
base standard: Approved international standard, technical report or ITU-T Recommendation
which is used in the definition of a Profile. [ISO/IEC TR 10000-1]
basic application function (in telecontrol): Transmission procedure that performs a
supervisory or control function that is generally used in telecontrol systems. [IEC 60870-5-5]
Examples: command transmission, event transmission, cyclic transmission, etc.
basic functions: Functions dealing with all types of individual information from and to the
operational equipment and the operator.
basic reference model: See open system interconnection
baud (Bd): Unit of modulation rate or unit of transfer rate of signal elements of constant
duration in a discretely timed or digital signal; the number of baud is equal to the reciprocal of
the duration in seconds of the shortest signal element or of the unit interval in such a signal.
[IEV 721-03-27]
NOTE – For example, if the duration of the unit interval is 20 ms, the modulation rate is 50 Bd.

– 18 – 60870-1-3 © CEI: 1997
information binaire d'état: Information de surveillance concernant l'état d'un organe ne
pouvant prendre que deux états, par exemple fermé et ouvert. [VEI 371-02-03]
probabilité d'effacement de bit: Probabilité qu'une variable d'un signal reçu, représentant la
valeur d'un bit, dépasse les limites de tolérance spécifiées pour la qualité du signal.
taux d'effacement de bits: Rapport du nombre de bits reçus dont les signaux dépassent les
limites de tolérance de qualité du signal au nombre total de bits émis.
probabilité d'erreurs sur les éléments binaires: Probabilité pour qu'un élément binaire reçu
soit inversé par rapport à l'élément binaire émis correspondant. [VEI 371-08-02]
taux d'erreur sur les éléments binaires: Rapport du nombre d'éléments binaires reçus
inversés au nombre total d'éléments binaires émis. [VEI 371-08-01]
transmission de données orientée bits: Voir «code transparent data transmission».
code orienté binaire: Voir «transparent code».
débit binaire: Vitesse à laquelle les bits sont transmis, habituellement exprimée en bits par
seconde (bits/s).
bloc: Suite de bits transmise d'un seul tenant, généralement divisée en champs de bits
d'information et en champs de bits de vérification d'erreurs.
code de bloc: Suite de bits d'information complétée par des bits servant à la détection ou à la
correction des erreurs.
probabilité d'erreurs sur les blocs: Probabilité qu'un bloc soit reçu de façon erronée.
[VEI 371-08-04]
taux d'erreur sur les blocs: Rapport du nombre de blocs reçus de façon erronée au nombre
total de blocs émis. [VEI 371-08-03]
bloqué: La valeur de l'objet de l'information est bloquée pour la transmission; la valeur reste à
l'état où elle a été acquise avant d'être bloquée. Le blocage et le déblocage peuvent être
initialisés à l'aide, par exemple, d'un verrou local ou par cause locale automatique).
transfert spontané de données bloqué: Similaire au «transfert spontané de données», mais
l'application qui initialise le processus attend un certain temps pour qu'il y ait plus de données
spontanées avant de transmettre, afin de permettre une transmission plus efficace en cas
d'afflux de données spontanées.
blocage: Fonction remplie par une entité (N) pour faire correspondre de multiples unités de
services de données (N) à un protocole d'unité de données (N). [ISO 7498]
code Bose Chaudhuri Hocquenghem (Code BCH): Code cyclique qui peut être défini par un
générateur polynomial: chaque mot codé est un multiple de ce polynôme.
pouvoir de coupure: Courant qu'un dispositif est capable de couper pour une tension de
rétablissement donnée, dans des conditions d'utilisation et de comportement données.
pont: Un nœud d'un réseau de transmission de données où sont interconnectées des lignes
utilisant des protocoles différents dans la couche physique.

60870-1-3 © IEC: 1997 – 19 –
binary state information: Monitored information of the status of operational equipment which
is characterized by one of two states, for example on/off. [IEV 371-02-03]
bit erasure probability: Probability that a received signal variable used to represent the value
of a bit exceeds specified limits of tolerated signal quality.
bit erasure rate: Ratio of the number of bits received with signals exceeding specified limits of
tolerated signal quality to the total number of bits sent.
bit error probability: Probability that a received bit will be inverted with respect to the
corresponding bit sent. [IEV 371-08-02]
bit error rate: Ratio of the number of bits received inverted to the total number of bits sent.
[IEV 371-08-01]
bit oriented data transmission: See code transparent data transmission
bit oriented code: See transparent code
bit rate: Speed at which bits are transmitted, usually expressed in bits per second (bits/s).
block: Sequence of bits transmitted as a unit, generally subdivided into fields for conveying
information bits and error check bits.
block code: Sequence of information bits completed by bits used for error detection or error
correction.
block error probability: Probability that a block will be incorrectly received. [IEV 371-08-04]
block error rate: Ratio of the number of blocks incorrectly received to the total number of
blocks sent. [IEV 371-08-03]
blocked: When the value of the information object is blocked for transmission, the value
remains in the state that was acquired before it was blocked. Blocking and deblocking may be
initiated e.g. by a local lock or a local automation cause.
blocked spontaneous data transfer: Similar to "spontaneous data transfer", but the initiating
application process waits a certain time for more spontaneous data before transmission to
allow a more efficient data transfer in the case of bursts of spontaneous data.
blocking: Function performed by an (N)-entity to map multiple (N)-service-data-units into one
(N)-protocol-data-unit. [ISO 7498]
Bose Chaudhuri Hocquenghem-code (BCH-code): Cyclic code that can be defined by a
generator polynomial; every code word is a multiple of that polynomial.
breaking capability: Current that a device is capable of breaking at a stated recovery voltage
under prescribed conditions of use and behaviour.
bridge: Relay
...