IEC TS 61804-1:2003

TECHNICAL IEC
SPECIFICATION
TS 61804-1
First edition
2003-10
Function blocks (FB) for process control –
Part 1:
Overview of system aspects
Reference number
IEC/TS 61804-1:2003(E)
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TECHNICAL IEC
SPECIFICATION
TS 61804-1
First edition
2003-10
Function blocks (FB) for process control –
Part 1:
Overview of system aspects
 IEC 2003  Copyright - all rights reserved
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– 2 – TS 61804-1  IEC:2003(E)
CONTENTS
FOREWORD . 5
INTRODUCTION .7
1 Scope . 9
2 Normative references.11
3 Terms, definitions and abbreviated terms.11
3.1 General definitions.11
3.2 Definitions based on IA/IM-channel.17
3.3 Abbreviated terms .18
4 Engineering requirements .18
4.1 General .18
4.2 Requirements for design phase .18
5 Compatibility levels.19
5.1 General .19
5.2 Incompatibility .21
5.3 Coexistence.21
5.4 Interconnectability .21
5.5 Interworkability .21
5.6 Interoperability.21
5.7 Interchangeability .21
6 Functional requirements .22
6.1 General .22
6.2 System (or channel or device) status .22
6.3 Validity index (VI) .24
6.4 Signal processing .24
6.5 Measurement information processing.24
6.6 Device diagnostics and test support.26
6.7 Local interfaces attachment .27
6.8 Device (and system and channel) management .27
7 FB application requirements .31
7.1 System overview.31
7.2 Overview of basic FB types.33
7.3 FB requirements .35
7.4 Initial sets of FBs derived from I&C.37
7.5 FB environment requirements .41
7.6 Communications requirements.43
8 Additional requirements .43
8.1 Cooperation with external applications.43
8.2 Additional characteristic requirements .47
8.3 Conformance requirements.49
9 Device descriptive language .49
9.1 Background .49
9.2 Basic requirements .49
9.3 General requirements .51

TS 61804-1  IEC:2003(E) – 3 –
Annex A (informative) Life cycle of the system .53
Annex B (informative) FB functional requirements: the user’s view.77
Annex C (informative) Relation between IEC 61804 series and IEC 61499-1.94
Annex D (informative) Mapping of an analogue input FB to IEC 61499 .106
Annex E (informative) FB requirement overview support .119
Annex F (informative) AME requirements .121
Bibliography.127
Figure A.1 – Life cycle from the process circuit to the FRDs.55
Figure A.2 – PFD composed of two process elementary operations.56
Figure A.3 – Control functions explicitly represented on the extended P&ID .57
Figure A.4 – Extraction of control functions from the extended P&ID .58
Figure A.5 – Requirements for control functions and ABs .59
Figure A.6 – Structured documentation for the requirements of the control functions.59
Figure A.7 – The four sections of a folio .60
Figure A.8 – Selection of a folio from the CHD .61
Figure A.9– Folio for detailed requirements of the control function "to control the pumps" .62
Figure A.10 – Example of FRDs .62
Figure A.11 – Functional requirements diagrams independent of I&C system
implementation.63
Figure A.12 – The need for a standardized FB language .64
Figure A.13 – Library of standardized EFBs .65
Figure A.14 – From FRDs down to the I&C system and devices .66
Figure A.15 – Design of an actuation and its AB from off-the-shelf actuation devices .67
Figure A.16 – Designing internal behaviour of actuation AB from actuation devices off
the shelf.67
Figure A.17 – Networking of the internal blocks inside the AB and with upstream and
downstream EFBs and ABs of the control function .68
Figure A.18 – Actuation AB graphic symbol and implicit internal description.69
Figure A.19 – OFF/ON value actuation AB using the IEC 61499-1 system model .69
Figure A.20 – OFF/ON value actuation AB using the IEC 61499-1 system model .70
Figure A.21 – Example of a safe switch over 2/3 AB.70
Figure A.22 – Switchover 2/3 AB using the IEC 61499-1 system model.71
Figure A.23 – From a FRD to a programming scheme using IEC 61499-1 system model .72
Figure A.24 – Distribution of the internal blocks of a pump AB .72
Figure A.25 – Distribution the EFBs and ABs of the control function "to control the
pumps" into the I&C architecture .73
Figure A.26 – Implementation of the control function into the I&C devices.74
Figure A.27 – Distribution of the control function "to control the pumps" using the
IEC 61499-1 model .74
Figure A.28 – From FRDs to programming schemes .75
Figure B.1– System properties .79
Figure B.2 – IA/IM channel validation .80

– 4 – TS 61804-1  IEC:2003(E)
Figure B.3 – Reference functional architecture for distributed automation systems .83
Figure B.4 – User view of the major component functions of each IAM function .84
Figure B.5 – IM channel/CMM interaction: user vision.86
Figure B.6 – Distributed platform using fieldbus: physical composition.86
Figure B.7 – Intelligent transmitter reference model .88
Figure C.1 – Structure of IEC 61499-1 FBs .95
Figure C.2 – Type specific aspects of IEC 61499-1 FBs.95
Figure C.3 – Implementation specific aspects .96
Figure C.4 – Distributed application and distributed operating system.96
Figure C.5 – Basic concepts of process control FBs.98
Figure C.6 – Functional components in process control FBs .99
Figure C.7 – IEC 61499-1 graphical representation of a process control FB (example) .99
Figure C.8 – Full structure of an EFB (example) .100
Figure C.9 – Relationship between IEC 61499-1, IEC 61804 series and other
standardization activities.101
Figure D.1 – Summary of the parameter of analogue input blocks.107
Figure D.2 – Simulation, mode and status diagram of analogue input block .107
Figure D.3 – Conditions of mode and status generation .108
Figure D.4 – State machine of the analogue input block.108
Figure D.5 – Example for the analogue input block parameter. .112
Figure D.6 – AI FB graphical representation.113
Figure D.7 – AI FB ECC.114
Figure F.1 – Naming and addressing approach .123
Table 1 – Functionality features .20
Table 2 – Example of initial FB set.37
Table 3 – Example of common list of EFBs .38
Table C.1 – Aspects overview of IEC 61499-1 FBs .97
Table C.2 – Reference between IEC 61499-1 and IEC 61804 components.105
Table D.1 – Conditions and results of the actual mode calculation .109
Table D.2 – Conditions and results of the status calculation from the output parameter .109
Table D.3 – Parameter attributes for the analogue input block .110
Table D.4 – Process parameter description.110
Table D.5 – Alarm parameter description .111
Table D.6 – Simulation.112
Table E.1 – Allocation of requirements to architecture components.119
Table E.2 – Overview of related requirements.120

TS 61804-1  IEC:2003(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FUNCTION BLOCKS (FB) FOR PROCESS CONTROL –
Part 1: Overview of system aspects
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
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
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• 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.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards. IEC 61804-1, which is a
Technical Specification, has been prepared by subcommittee 65C: Digital communications, of
IEC technical committee 65: Industrial-process measurement and control.
This standard cancels and replaces IEC/PAS 61804-1 published in 2002.

– 6 – TS 61804-1  IEC:2003(E)
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
65C/296/DTS 65C/310A/RVC
Full information on the voting for the approval of this technical specification 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.
IEC 61804 consists of the following parts under the general title Function blocks (FB) for
process control
Part 1: Overview of system aspects
Part 2: Specification of FB concept and electronic device description language (EDDL)
The committee has decided that the contents of this publication will remain unchanged until
2007. At this date, the publication will be
• transformed into an International standard;
• reconfirmed;
• withdrawn;
• replaced by a revised edition, or
• amended.
TS 61804-1  IEC:2003(E) – 7 –
INTRODUCTION
This Technical Specification is an end-user driven specification of the requirements of
distributed process control systems based on Function Blocks (FB). This Technical
Specification and its associated FB standard (IEC 61804-2) originate from the power-plant
industrial sector. It is validated by applications in oil and gas, petrochemicals,
pharmaceuticals and fine chemicals, pulp and paper, food and beverage, waste water
treatment plants, steel milling and others. There will be other general requirement standards
and associated specifications for other industrial sectors.
Present and future digital process control systems need to fulfil the following requirements:
• increase security and safety;
• reduce time to market;
• be supportable with available tools;
• reduce costs of development and support;
• minimize training costs;
• support integration of distributed control applications
• support integrated methodology for implementation;
• have increased maintainability, modifiability, agility, upgradeability, flexibility, ability to
validate, accessibility, availability, compatibility of support tools, multi-vendor device/
application compatibility, re-usability of knowledge and designs, re-usability of software
components;
• be made up of digital devices that are compatible, interworkable, interconnectable
interoperable and interchangeable with each other.
Process control systems are required to fulfil these requirements in terms of their architecture
and their operation during all the phases of the life cycle. The accepted basic concept for the
design process control system is to describe all necessary implementation-specific functions
with FB. A FB is an encapsulation of data and algorithms to provide a specific function, which
can be self-standing. Process control systems can involve many instances of many different
FBs operating in an environment providing common services (for example, communications)
and interfaces to other applications. See Figure 1.

– 8 – TS 61804-1  IEC:2003(E)
Configuration
Control, maintenance
function
monitoring, HMI*,
application
application
Different
interaction
types
D1 D2 Dn
D1   Devices, part of
...
a distributed
automation
Dn
* Human Machine Interface
system
Figure 1 – Interactions of applications

TS 61804-1  IEC:2003(E) – 9 –
FUNCTION BLOCKS (FB) FOR PROCESS CONTROL –
Part 1: Overview of system aspects
1 Scope
This part of IEC 61804 is a Technical Specification which provides guidelines for suppliers to
meet evolving requirements for digital process control systems through which users can be
assured of the compatibility, the interworkability, the interconnectability, the interoperability
and the interchangeability of the devices they choose. This part gives the overall
requirements. For better understanding, this part gives background information and examples
in annexes.
This Technical Specification defines the requirements for FBs to provide control and to
facilitate maintenance and technical management as applications which interact with
actuators and measurement devices:
• control covers functions necessary to bring and hold the process at the desired behaviour;
• maintenance covers functions to acquire information about the state of the process
equipment and the state of automation devices including their adjustments, for example,
calibrate a sensor that has drifted;
• technical management deals with information for the optimization of the process.
It is concerned primarily with the economics of the process and plant equipment. This
relates in particular to the evaluation of performance and reliability of specific items of
plant or equipment for all the installed period and comparison of performance and
reliability of items from different suppliers performing an identical function in the same
operating environment. An example of performance is the number of cycles achieved
before failure of two valves from different suppliers. This allows for the production of
detailed and valid statistical analysis to support management decisions and plant
equipment modifications.
A prerequisite for designing, implementing and operating a FB-based process control system
is that the tools, the devices and other components follow the same architecture based on a
common specification. The architecture is required to define the components of the systems,
for example FB, device, data, data connections and more as well as relations between these
components. The IEC 61499 series generic FB model on which this Technical Specification is
related is able to provide these basic components for FBs for process control. One add-on to
the IEC 61499 series is the specification of parameters and functions of FBs that are
implementable in devices.
The architecture and the range of FBs that have to be specified are described in 7.4 contains
a minimum set of FBs that will be required for the process industries. These are presented in
TWO different clauses. One deals with “rich” FBs covering complex but common functions
such as control loop (for example proportional, integral, differential – PID) required by the
majority of the process industries. Another covers a set of elementary FBs (EFB) such as
Boolean functions required to compose very specific and unique functionality.
FBs are used during the complete life cycle of process control systems but viewed from
different aspects. This is covered in detail in Annex A. The process design starts with the
Piping and Instrumentation Diagram (P&ID) which gives the requirements of the process and
instrumentation from a purely functional point of view. From the P&ID, the desired behaviour
of the process control system is extracted into a functional requirements diagram (FRD)
without considering the detailed behaviour of the underlying devices. The bricks making up
the FRD are application blocks (AB), the representation of the data and algorithms in the

– 10 – TS 61804-1  IEC:2003(E)
design phase. After discussion between the process and automation engineers (end-user and
system integrator), the FRDs are turned into detailed designs for the application via several
design using devices available on the market together with interconnections and
configurations of these devices. In this way a PID loop shown in via bubbles on a P&ID will be
transformed into implementable FBs in specific field and/or control-room devices. It should be
noted that many parts of the process industries, in particular those with many similar and
relatively simple processes (for example, the water industry), do not use the concept or term
FRD. They go directly from P&IDs to the implementable FBs and will use a variety of names
to describe the process and the resulting design documents. The FRD approach is used here
since it represents the most formal view of the design cycle and illustrates the use of FBs at
the earliest of phases in the life cycle. Clause 4 summarizes the requirements from this life-
cycle point of view.
This Technical Specification specifies a system (an industrial-process measurement and
control system based on distributed FB application). A system is described stepwise in terms
of architecture, models and the life cycle. The architecture is the "road map" which names the
components and presents the structure of the system. The models describe the details of the
components, i.e. their functions in the system. The life cycle makes visible how the
components work together during their use in different phases of the lifetime, i.e. it makes the
operation visible.
Figure 2 shows the different influences, basic specifications and technology support on
IEC 61804 from the top-down and bottom-up point of view.
IEC 61499 series
generic FB model
USER REQUIREMENTS
PRIAM METHODOLOGY
User Layer for
process control
ISO TC184, SC4
ISA SP50 User Layer TR
(implicit)
ACORN
Specify the application with FB independent of the technology supported
Top-down
IEC 61804
Bottom-up
Provide the knowledge to implement the application
FB SPECIFICATION
IEC 61158 series and
ISA SP50 User Layer TR
IEC 61784 series
Fieldbus Foundation
FIELDBUS SPECIFICATION
PROFIBUS
NOAH
IEC 61131 series
APPLICATION DESCRIPTION
Basic models
Figure 2 – Influences on IEC 61804

TS 61804-1  IEC:2003(E) – 11 –
The influences are international standards and projects (PROFIBUS and Fieldbus
Foundation ), which relate to the same area as IEC 61804. These standards are either
technology-independent ones supporting the top-down approach or dedicated to a certain
technology, for example, programmable controller or fieldbus. Both together will build the
basis of the standard specified by IEC 61804.
The main purpose of this part is the harmonization of different views, models and starting
points of end-users, system providers and device manufacturers. It will be the reference
document leading the discussions during the specification and the guideline for the readers of
IEC 61804-2.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 61131-3:1992, Programmable controllers – Part 3: Programming languages
IEC 61499-1:2000, Function blocks for industrial-process measurement and control systems –
Part 1: Architecture
IEC 61512-1:1997, Batch control – Part 1:Models and terminology
IEC 61784:2003, Digital data communications for measurement and control – Part 1: Profile
sets for continuous and discrete manufacturing − Fieldbus relative to use in industrial control
systems
IEC 61158 (all parts), Digital data communication for measurement and control – Fieldbus for
use in industrial control systems
IEC 61804-2, Function blocks for process control – Part 2: Specification of FB concept and
Electronic Device Description Language (EDDL)
EN 50170:1996, General purpose field communication system
3 Terms, definitions and abbreviated terms
3.1 General definitions
For the purposes of this document, the following definitions apply.
3.1.1
interface
shared boundary between two functional units, defined by functional characteristics, signal
characteristics, or other characteristics as appropriate
[IEC 60050-351:1998, 11-19]
———————
PROFIBUS is the registered trade mark of PROFIBUS International (PI). PI is a non-profit trade organization to
support the fieldbus PROFIBUS. This information is given for the convenience of users of this Technical
Specification and does not constitute an endorsement by CENELEC of the trademark holder or of any of its
products. Compliance to this profile does not require use of the trade name PROFIBUS. Use of the trade name
PROFIBUS requires permission of the trade-name holder.
Foundation Fieldbus is the trade name of the consortium Fieldbus Foundation. This information is given for the
convenience of users of this Technical Specification and does not constitute an endorsement by CENELEC of the
product named. Equivalent products may be used if they can be shown to lead to the same results.
To be published.
– 12 – TS 61804-1  IEC:2003(E)
3.1.2
system
set of interrelated elements considered in a defined context as a whole and separated from its
environment
[IEC 60050-351:1998, 11-01]
NOTE 1 Such element may be material objects and concepts as well as the results thereof (for example forms of
organization, mathematical methods, and programming languages).
NOTE 2 The system is considered to be separated from the environment and other external systems by an
imaginary surface, which can cut the links between them and the system considered.
3.1.3
data type
set of values together with a set of permitted operations
[ISO 2382 series]
3.1.4
data connection
association between two function blocks for the conveyance of data
[IEC/PAS 61499-1:2000, 1.3.2.22]
3.1.5
data
representation of facts, concepts or instructions in a formalized manner suitable for
communication, interpretation or processing by human beings or by automatic means
[ISO modified ]
3.1.6
functional unit
entity of hardware or software, or both, capable of accomplishing a specified purpose
[ISO 2382 series]
3.1.7
hardware
physical equipment, as opposed to programs, procedures, rules and associated
documentation
[ISO modified ]
3.1.8
mapping
set of values having defined correspondence with the quantities or values of another set
[ISO 2382 series]
3.1.9
parameter
variable that is given a constant value for a specified application and that may denote the
application
[ISO 2382 series]
———————
The notation [ISO modified] following a definition indicates that the definition is taken from the “ISO/AFNOR
Dictionary of Computer Science” and has been modified.

TS 61804-1  IEC:2003(E) – 13 –
3.1.10
algorithm
finite set of well-defined rules for the solution of a problem in a finite number of operations
[IEC/PAS 61499-1:2000, 1.3.2.5]
3.1.11
application
software functional unit that is specific to the solution of a problem in industrial-process
measurement and control
[IEC/PAS 61499-1:2000, 1.3.2.6]
NOTE An application may be distributed among resources, and may communicate with other applications.
3.1.12
application block
design pattern which is used in an FRD to represent one or multiple (rich) functions blocks
3.1.13
attribute
property or characteristic of an entity, for instance, the version identifier of a FB type
specification
[IEC/PAS 61499-1:2000, 1.3.2.7]
NOTE The formal description of attributes is to specify interoperability. IEC 61499-1 does not specify certain
attributes like FB type information. IEC 61499-1 gives the general rules to define the attributes and IEC 61804-2
specifies the attributes for process control as other groups may specify their own. Rules should be able to prevent
non-unique attribute names.
3.1.14
configuration (of a system or device)
step in system design: selecting functional units, assigning their locations and defining their
interconnections
[IEC/PAS 61499-1:2000, 1.3.2.17]
3.1.15
device
independent physical entity capable of performing one or more specified functions in a
particular context and delimited by its interfaces
[IEC/PAS 61499-1:2000, 1.3.2.26]
3.1.16
device management application
application whose primary function is the management of a multiple resources within a device
[IEC/PAS 61499-1:2000, 1.3.2.27]
3.1.17
elementary FB
FB or function which provide logico-mathematical functionality with exception handling
NOTE There can be a difference between an EFB used in the FRD and the FB in the operating application
3.1.18
entity
particular thing, such as a person, place, process, object, concept, association, or event
[IEC/PAS 61499-1:2000, 1.3.2.28]

– 14 – TS 61804-1  IEC:2003(E)
3.1.19
event
instantaneous occurrence that is significant to scheduling the execution of an algorithm
[IEC/PAS 61499-1:2000, 1.3.2.29]
NOTE The execution of an algorithm may make use of variables associated with an event.
3.1.20
exception
event that causes suspension of normal execution
[IEC/PAS 61499-1:2000, 1.3.2.35]
3.1.21
execution
process of carrying out a sequence of operations specified by an algorithm
NOTE The sequence of operations to be executed may vary from one invocation of a function block instance to
another, depending on the rules specified by the FB algorithm and the current values of variables in the FB data
structure.
[IEC/PAS 61499-1:2000, 1.3.2.36]
3.1.22
function
specific purpose of an entity or its characteristic action
[IEC/PAS 61499-1:2000, 1.3.2.42]
3.1.23
FB (FB instance)
software functional unit comprising an individual, named copy of a data structure and
associated operations specified by a corresponding FB type
NOTE Typical operations of a FB include modification of the values of the data in its associated data structure.
[IEC/PAS 61499-1:2000, 1.3.2.43]
3.1.24
implementation
development phase in which the hardware and software of a system become operational
[ISO modified ]
3.1.25
input variable
variable whose value is supplied by a data input, and which may be used in one or more
operations of a FB
NOTE An input parameter of a FB, as defined in IEC 61131-3, is an input variable.
[IEC/PAS 61499-1:2000, 1.3.2.48]
3.1.26
instance
functional unit comprising an individual, named entity with the attributes of a defined type
[IEC/PAS 61499-1:2000, 1.3.2.49]

TS 61804-1  IEC:2003(E) – 15 –
3.1.27
instance name
identifier associated with and designating an instance
[IEC/PAS 61499-1:2000, 1.3.2.50]
3.1.28
instantiation
creation of an instance of a specified type
[IEC/PAS 61499-1:2000, 1.3.2.51]
3.1.29
internal operations (of a FB)
operations associated with an algorithm of a FB, with its execution control, or with the
functional capabilities of the associated resource
[IEC/PAS 61499-1:2000, 1.3.2.52]
3.1.30
internal variable
variable whose value is used or modified by one or more operations of a FB but is not
supplied by a data input or to a data output.
[IEC/PAS 61499-1:2000, 1.3.2.53]
3.1.31
invocation
process of initiating the execution of the sequence of operations specified in an algorithm
[IEC 61131-3, modified]
3.1.32
management FB
FB whose primary function is the management of applications within a resource
[IEC/PAS 61499-1, 1.3.2.56]
3.1.33
management resource
resource whose primary function is the management of other resources
[IEC/PAS 61499-1:2000, 1.3.2.57]
3.1.34
model
representation of a real world process, device, or concept
[IEC/PAS 61499-1:2000, 1.3.2.58]
3.1.35
operation
well-defined action that, when applied to any permissible combination of known entities,
produces a new entity
– 16 – TS 61804-1  IEC:2003(E)
3.1.36
output variable
variable whose value is established by one or more operations of a FB and is supplied to a
data output
NOTE An output parameter of a FB, as defined in IEC 61131-3, is an output variable.
[IEC/PAS 61499-1:2000, 1.3.2.60]
3.1.37
resource
functional unit which has independent control of its operation and which provides various
services to applications, including the scheduling and execution of algorithms
NOTE 1 The resource defined in IEC 61131-3 is a programming language element corresponding to the resource
defined above.
NOTE 2 A device contains one or more resources.
[IEC/PAS 61499-1:2000, modified]
3.1.38
resource management application
application whose primary function is the management of a single resource
[IEC/PAS 61499-1:2000, 1.3.2.66]
3.1.39
scheduling function
function which selects algorithms or operations for execution, and initiates and terminates
such execution
[IEC/PAS 61499-1:2000, 1.3.2.70]
3.1.40
service
functional capability of a resource which can be modeled by a sequence of service primitives
[ISO/IEC 7498-1, modified]
3.1.41
software
intellectual creation comprising the programs, procedures, rules and any associated
documentation pertaining to the operation of a system
[ISO modified ]
3.1.42
transaction
unit of service in which a request and possibly data are conveyed from a requester to a
responder, and in which a response and possibly data may also be conveyed from the
responder back to the requester
[IEC/PAS 61499-1:2000, 1.3.2.79]
3.1.43
type
software element which specifies the common attributes shared by all instances of the type
[IEC/PAS 61499-1:2000, 1.3.2.80]

TS 61804-1  IEC:2003(E) – 17 –
3.1.44
type name
identifier associated with and designating a type
[IEC/PAS 61499-1:2000, 1.3.2.81]
3.1.45
variable
software entity that may take different values, one at a time
NOTE 1 The values of a variable are usually restricted to a certain data type.
NOTE 2 Variables may be classified as input variables, output variables, and internal variables.
[ISO modified ]
3.2 Definitions based on IA/IM-channel
3.2.1
actuation (measurement) channel
sum of all the items necessary to perform each actuation (measurement) as users need it.
The physical composition extends from the attachment to the process, to the valve, motor,
actuator (sensor, transmitter), the network, and the complementary processing in the
computers
NOTE The expression IA/IM-channel means intelligent actuation/measurement solution of all the requirements for
each actuation/measurement necessary. Intelligent here means provided with all the functionalities as users need
them.
3.2.2
system (or channel or device) status
actual health (or condition) of the related item (system or channel or device). In other words it
is defined at the several levels of system distribution: the system as a whole, each IA/IM-
channel of the system, each device composing the channel
NOTE A detailed explanation is given in 6.2.
3.2.3
validity index (VI)
qualifier of the information to which it is added. It can be seen as a quality index
NOTE A detailed explanation is given in 6.3.
3.2.4
measurement uncertainty
parameter associated with the actual result of a measurement, which characterizes the
dispersion of the values that could reasonably be attributed to the measured
NOTE 1 The word "uncertainty" means "doubt", and thus, in its broadest sense, "uncertainty of measurement"
means the extent of doubt about the exactness or accuracy of the result of a measurement.
NOTE 2 The uncertainty may be, for example, a standard deviation or the width of a confidence interval.
NOTE 3 The uncertainty can be expressed with data which can be treated mathematically, so that the uncertainty
of an indirect measurement can be calculated if the uncertainty of the several component direct measurements are
known.
3.2.5
profile
set of one or more base standards and/or ISPs, and, where applicable, the identification of
chosen classes, conforming subsets, options and parameters of those base standards, or
ISPs necessary to accomplish a particular function
[ISO/IEC 10000-1]
NOTE ISPs may contain normative references to specifications other than International Standards.

– 18 – TS 61804-1  IEC:2003(E)
3.3 Abbreviated terms
AB Application Block
AME Application Management Entity
CHD Control Hierarchy Diagram
CMM
...