IEC 61987-11:2012

Industrial-process measurement and control - Data structures and elements in process equipment catalogues - Part 11: List of Properties (LOP) of measuring equipment for electronic data exchange - Generic structures

IEC 61987-11:2012 provides a characterisation of industrial process measuring equipment (device type dictionary) for integration in the Component Data Dictionary (CDD) and generic structures for Operating Lists of Properties (OLOPs) and Device Lists of Properties (DLOPs) of measuring equipment in conformance with IEC 61987-10. This bilingual version (2014-01) corresponds to the monolingual English version, published in 2012-07.

Mesure et contrôle des processus industriels - Structures de données et éléments dans les catalogues d'equipement de processus - Partie 11: Liste de propriétés (LOP) d'équipements de mesure pour échange de données électronique - Structures génériques

L'IEC 61987-11:2012 fournit une caractérisation des équipements de mesure de processus industriels (dictionnaire des types de dispositifs) pour l'intégration dans le dictionnaire de données de composants (CDD, en anglais "Component Data Dictionary") et des structures génériques pour les listes de propriétés fonctionnelles (OLOP, en anglais "Operating List of Properties") et les listes de propriétés des dispositifs de mesure (DLOP, en anglais "Device List of Properties") en conformité avec la CEI 61987-10. La présente version bilingue (2014-01) correspond à la version anglaise monolingue publiée en 2012-07.

General Information

• Status: Published
• Publication Date: 23-Jul-2012
• ICS: 25.040.40 - Industrial process measurement and control
• ICS: 35.100.20 - Data link layer
• Technical Committee: SC 65E - Devices and integration in enterprise systems
• Drafting Committee: WG 2 - TC 65/SC 65E/WG 2
• Current Stage: DELPUB - Deleted Publication
• Start Date: 15-Dec-2016
• Completion Date: 26-Oct-2025

Relations

• Revised: IEC 61987-11:2016 - Industrial-process measurement and control - Data structures and elements in process equipment catalogues - Part 11: List of properties (LOPs) of measuring equipment for electronic data exchange - Generic structures
• Effective Date: 05-Sep-2023

Overview

IEC 61987-11:2012 - Industrial-process measurement and control - Part 11 - defines generic data structures for the List of Properties (LOP) of process measuring equipment intended for electronic data exchange. The standard provides a characterisation (device type dictionary) of measuring equipment suitable for integration in the Component Data Dictionary (CDD) and supplies generic structures for Operating Lists of Properties (OLOPs) and Device Lists of Properties (DLOPs). This bilingual edition (2014-01) corresponds to the English monolingual edition published in 2012.

Key topics and technical requirements

• Characterisation scheme: A structured approach to describe measuring equipment by device type and aspects, enabling consistent device-type dictionaries.
• Generic block structures: Defined templates for OLOPs and DLOPs that standardize how properties are grouped and represented for electronic exchange.
• OLOP (Operating List of Properties): Covers base conditions, process cases, operating conditions for device design (installation, environment, process, P-T), and physical location aspects.
• DLOP (Device List of Properties): Focuses on device identification, application, function and system design, inputs/outputs, digital communication interfaces, performance and rated operating conditions.
• Composite devices: Rules for structuring composite or multivariable devices and mapping component aspects.
• Support blocks: Administrative information, calibration/test data, accessories, certificates and part identifications.
• Normative structure links: Conformance with IEC 61987-10 and relationship to IEC 61987-1 for wider catalogue data structures.
• Annex A: Device type dictionary classification scheme for process measuring equipment.

Practical applications and who uses it

IEC 61987-11 is used where standardized, machine-readable device data is required for the lifecycle of process instrumentation:

• Instrument manufacturers: to publish product catalogues and device-type data compatible with the CDD and digital procurement.
• System integrators and automation engineers: for device selection, configuration, and interoperable integration into control systems and asset management.
• Software vendors and data-modelers: to implement consistent OLOP/DLOP data models in CMMS, PIM, digital twins and engineering tools.
• Procurement and operations teams: to automate specification matching, ordering and verification against rated operating conditions and certifications.

Related standards

• IEC 61987-10 - referenced for LOP conformance rules
• IEC 61987-1 - overarching data structures and catalogue elements
• Component Data Dictionary (CDD) - target integration environment for device-type dictionaries

By standardizing Lists of Properties (LOP), IEC 61987-11 improves interoperability, reduces manual data entry, and streamlines electronic exchange of instrument specifications across the industrial-process measurement and control ecosystem.

Standards Content (Sample)

IEC 61987-11 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
Industrial-process measurement and control – Data structures and elements
in process equipment catalogues –
Part 11: List of Properties (LOP) of measuring equipment for electronic data
exchange – Generic structures
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IEC 61987-11 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
Industrial-process measurement and control – Data structures and elements

in process equipment catalogues –

Part 11: List of Properties (LOP) of measuring equipment for electronic data

exchange – Generic structures
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XA
ICS 25.040.40; 35.100.20 ISBN 978-2-83220-283-8

– 2 – 61987-11 © IEC:2012(E)
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Terms and definitions concerning measuring instruments . 10
3.2 Terms and definitions concerning relationships . 11
4 General . 13
4.1 Characterization scheme . 13
4.2 Aspects . 13
4.3 Rules for the construction of LOPs with block structure . 15
4.3.1 Block order . 15
4.3.2 Position of cardinality properties . 15
4.3.3 Naming of blocks created by cardinality . 15
4.3.4 Characterizing property . 15
4.3.5 Validity . 15
4.4 OLOP and DLOP . 15
4.5 Operating conditions . 16
4.6 Measuring equipment configuration . 17
5 Operating List of Properties (OLOP) . 18
5.1 Generic block structure . 18
5.2 Base conditions . 18
5.3 Process case . 19
5.3.1 General . 19
5.3.2 Process case variables . 19
5.3.3 Other process case variable . 20
5.4 Operating conditions for device design . 20
5.4.1 General . 20
5.4.2 Installation design conditions . 20
5.4.3 Environmental design conditions . 20
5.4.4 Process design conditions . 21
5.4.5 Pressure-temperature design conditions . 21
5.5 Process equipment . 22
5.5.1 General . 22
5.5.2 Line or equipment nozzle . 22
5.6 Physical location . 22
5.6.1 General . 22
5.6.2 Available power supply . 22
5.6.3 Process criticality classification . 23
5.6.4 Area classification . 23
6 Device list of properties (DLOP) . 23
6.1 General . 23
6.1.1 Generic block structure . 23
6.1.2 Relationship to IEC 61987-1 . 25

61987-11 © IEC:2012(E) – 3 –
6.1.3 Multivariable devices . 25
6.2 Identification . 25
6.3 Application . 26
6.4 Function and system design . 26
6.4.1 General . 26
6.4.2 Dependability . 26
6.5 Input . 26
6.5.1 General . 26
6.5.2 Measured variable . 26
6.5.3 Auxiliary input . 27
6.6 Output . 28
6.6.1 General . 28
6.6.2 output . 28
6.7 Digital communication . 29
6.7.1 General . 29
6.7.2 Digital communication interface . 29
6.8 Performance . 30
6.8.1 General . 30
6.8.2 Reference conditions for the device . 30
6.8.3 Performance variable. 30
6.9 Rated operating conditions . 32
6.9.1 General . 32
6.9.2 Installation conditions . 32
6.9.3 Environmental design ratings . 32
6.9.4 Process design ratings . 33
6.9.5 Pressure-temperature design ratings . 34
6.10 Mechanical and electrical construction . 34
6.10.1 General . 34
6.10.2 Overall dimensions and weight . 34
6.10.3 Structural design . 34
6.10.4 Explosion protection design approval . 34
6.10.5 Codes and standards approval . 34
6.11 Operability . 35
6.11.1 General . 35
6.11.2 Basic configuration . 35
6.11.3 Parametrization . 35
6.11.4 Adjustment . 35
6.11.5 Operation . 35
6.11.6 Diagnosis . 35
6.12 Power supply . 35
6.13 Certificates and approvals . 35
6.14 Component part identifications . 35
7 Composite devices . 36
7.1 Structure of composite devices . 36
7.2 Aspects of components . 37
8 Additional aspects . 38
8.1 Administrative information . 38
8.2 Calibration and test . 38
8.3 Accessories . 38

– 4 – 61987-11 © IEC:2012(E)
8.4 Device documents supplied . 38
8.5 Packaging and shipping. 39
8.6 Digital communication parametrization . 39
8.7 Example of a composite device with aspects . 39
Annex A (normative) Device type dictionary – Classification of process measuring
equipment according to measuring characteristics . 40
Bibliography . 53

Figure 1 – Characterisation of measuring equipment . 13
Figure 2 – Simplified UML scheme of device, LOPs and aspects . 14
Figure 3 – Assignment of OLOPs and DLOPs for equipment used to measure one type
of measured variable . 16
Figure 4 – Structure of a composite device . 36
Figure 5 – Example for the structure of a LOP for a composite device showing different
aspects related to different sub-components . 39

Table 1 – Structure of the “Operating conditions for device design” block in the OLOP . 17
Table 2 – Structure of the “rated operating conditions” block in the DLOP . 17
Table 3 – Generic block structure of an OLOP . 18
Table 4 – Generic block structure of a DLOP . 24
Table 5 – DLOP structure for composite devices . 37
Table A.1 – Classification scheme for process measuring equipment . 40

61987-11 © IEC:2012(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL-PROCESS MEASUREMENT AND CONTROL –
DATA STRUCTURES AND ELEMENTS
IN PROCESS EQUIPMENT CATALOGUES –

Part 11: List of Properties (LOP) of measuring equipment
for electronic data exchange –
Generic structures
FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61987-11 has been prepared by subcommittee 65E: Devices and
integration in enterprise systems, of IEC technical committee 65:Industrial-process
measurement, control and automation.
The text of this standard is based on the following documents:
FDIS Report on voting
65E/245/FDIS 65E/270/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.

– 6 – 61987-11 © IEC:2012(E)
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61987 series, published under the general title, Industrial-process
measurement and control – Data structures and elements in process equipment catalogues,
can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

61987-11 © IEC:2012(E) – 7 –
INTRODUCTION
0.1 General
The exchange of product data between companies, business systems, engineering tools, data
systems within companies and, in the future, control systems (electrical, measuring and
control technology) can run smoothly only when both the information to be exchanged and the
use of this information has been clearly defined.
Prior to this standard, requirements on process control devices and systems were specified by
customers in various ways when suppliers or manufacturers were asked to quote for suitable
equipment. The suppliers in their turn described the devices according to their own
documentation schemes, often using different terms, structures and media (paper, databases,
CDs, e-catalogues, etc.). The situation was similar in the planning and development process,
with device information frequently being duplicated in a number of different information
technology (IT) systems.
Any method that is capable of recording all existing information only once during the planning
and ordering process and making it available for further processing, gives all parties involved
an opportunity to concentrate on the essentials. A precondition for this is the standardization
of both the descriptions of the objects and the exchange of information.
This standard series proposes a method for standardization which will help both suppliers and
users of measuring equipment to optimize workflows within their own companies as well as in
their exchanges with other companies. Depending on their role in the process, engineering
firms may be considered here to be either users or suppliers.
The method specifies measuring equipment by means of blocks of properties. These blocks
are compiled into lists of properties (LOPs), each of which describes a specific equipment
(device) type. This standard series covers both properties that may be used in an inquiry or a
proposal and detailed properties required for integration of the equipment in computer
systems for other tasks.
IEC 61987-10 defines structure elements for constructing lists of properties for electrical and
process control equipment in order to facilitate automatic data exchange between any two
computer systems in any possible workflow, for example engineering, maintenance or
purchasing workflow and to allow both the customers and the suppliers of the equipment to
optimize their processes and workflows. Part 10 also provides the data model for assembling
the LOPs.
This part of the IEC 61987 series specifies the generic structure for operating and device lists
of properties (OLOPs and DLOPs). It lays down the framework for further parts of IEC 61987
in which complete LOPs for device types measuring a given physical variable and using a
particular measuring principle will be specified. The generic structure may also serve as a
basis for the specification of LOPs for other industrial-process control instrument types such
as control valves and signal processing equipment.
0.2 Content of the lists of properties (LOPs)
The LOPs specified in this standard describe at generic level:
• the operating conditions of the measuring equipment,
• the ambient conditions at the measuring point,
• the performance of the measuring equipment,
• the metrological, mechanical and electrical features of the measuring equipment,

– 8 – 61987-11 © IEC:2012(E)
• the compliance of the measuring instrument to specific industrial requirements.
The LOPs mirror constructive reality but do not represent an instrument model.
0.3 Measuring equipment configuration
The generic LOPs have been so constructed that they take account of integral equipment and
separately mounted equipment.
0.4 Device type dictionary
Annex A of this part describes a characterisation of measuring equipment based on the STEP
library, ISO 10303. This is a tree of relationships between different device types. Starting at
the root “automation equipment”, it first characterizes measuring equipment according to type,
then according to process variable measured and finally according to the measuring method
employed. This structure will be used in the IEC Component Data Dictionary (CDD)
“Automation equipment” Domain.
For the purpose of this standard the following types of measuring equipment have been
identified and defined in Clause 3: sight indicator, gauge, transmitter, switch and measuring
assembly.
It should be noted that in the real world, there is not such a clear demarcation between types
of measuring equipment. In commercial literature indicators are often called gauges, although
the products offer no quantitative measurement. Similarly, direct indicating displays are often
equipped with electrical trip switches which allow a gauge to act as a switch. Finally,
“transmitter” is by no means a universal term and in particular for flow measurement many
manufacturers call this kind of equipment “meter”.
0.5 Composite devices
A structural scheme is given, defining how to build up LOPs for devices consisting of several
components or assembled from different parts, that is, composite devices and measuring
assemblies.
61987-11 © IEC:2012(E) – 9 –
INDUSTRIAL-PROCESS MEASUREMENT AND CONTROL –
DATA STRUCTURES AND ELEMENTS
IN PROCESS EQUIPMENT CATALOGUES –

Part 11: List of Properties (LOP) of measuring equipment
for electronic data exchange –
Generic structures
1 Scope
This part of IEC 61987 provides
• a characterisation of industrial process measuring equipment (device type dictionary) for
integration in the Component Data Dictionary (CDD), and
• generic structures for Operating Lists of Properties (OLOPs) and Device Lists of
Properties (DLOPs) of measuring equipment in conformance with IEC 61987-10.
The generic structures for the OLOPs and DLOPs contain the most important blocks for
process measuring equipment. Blocks pertaining to a specific equipment type will be
described in the corresponding part of the IEC 61987 series (for example IEC 61987-12, flow
transmitters). Similarly, equipment properties are not dealt with in this part of the series For
instance, the OLOPs and DLOPs for flow transmitters with blocks and properties will be found
in future in IEC 61987-12.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61069-5, Industrial-process measurement and control – Evaluation of system properties
for the purpose of system assessment – Part 5: Assessment of system dependability
IEC 61508-6, Functional safety of electrical/electronic/programmable electronic safety-related
systems – Part 6: Guidelines on the application of IEC 61508-2 and IEC 61508-3
IEC 61987 (all parts), Industrial-process measurement and control – Data structures and
elements in process equipment catalogues
IEC 61987-1:2006, Industrial-process measurement and control – Data structures and
elements in process equipment catalogues – Part 1: Measuring equipment with analog and
digital output
IEC 61987-10:2009 Industrial-process measurement and control – Data structures and
elements in process equipment catalogues – Part 10: Lists of Properties (LOPs) for Industrial-
Process Measurement and Control for Electronic Data Exchange – Fundamentals
IEC 62424, Representation of process control engineering – Requests in P&I diagrams and
data exchange between P&ID tools and PCE-CAE tools

– 10 – 61987-11 © IEC:2012(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Terms and definitions concerning measuring instruments
3.1.1
composite device with main component
device composed of various devices, whereby one is designated the main component
Note 1 to entry: These devices might be supplied as a whole or the parts comprising the assembly of the
composite device might be supplied individually.
EXAMPLE A control valve which consists of the valve itself (main component), an actuator and a positioner.
3.1.2
gauge
measuring instrument intended to measure and indicate directly a measured value without
auxiliary energy supply
Note 1 to entry: In process engineering a gauge is often called an indicator.
Note 2 to entry: A gauge equipped with electrical contacts in order to transmit one or more measured values to
external equipment is still considered to be a gauge within the scope of this standard.
3.1.3
instrument component
entity within an instrument that plays a specific role and which can be handled separately if
necessary
EXAMPLES Thermowell within a temperature assembly, remote seal for a pressure transmitter.
3.1.4
integral transmitter
transmitter mounted as an integral part of an assembly containing the sensing element
3.1.5
measuring assembly
measuring instrument comprising several required and/or optional components which together
function as a gauge, transmitter or switch
Note 1 to entry: The components can often be ordered separately and as such require their own DLOPs.
Note 2 to entry: A measuring assembly may also be called a composite device.
3.1.6
measuring instrument
artefact intended to detect an aspect of a material to record, transform or display such an
aspect or to perform a combination of these activities
3.1.7
PCE identifier
tag name
identifier assigned by the user to uniquely define the instrument or a component thereof
Note 1 to entry: PCE = Process Control Engineering.

61987-11 © IEC:2012(E) – 11 –
3.1.8
sensing element
instrument component that is the primary element of a measuring chain and which may
convert the input variable into a signal suitable for use by other instruments in that chain
Note 1 to entry: It is intended to respond to a physical stimulus and to produce a corresponding resulting signal.
3.1.9
separate transmitter
transmitter mounted at a location removed (locally or remotely) from an assembly containing
the sensing element but connected to it by signal line
Note 1 to entry: A head-mounted transmitter is a separate transmitter mounted in a connection head.
3.1.10
sight indicator
measuring instrument that provides a means of visually inspecting a process regime and
provides only a qualitative indication
Note 1 to entry: IEC 60770-1 defines “indicator” as an instrument intended to visually indicate a physical quantity.
3.1.11
switch
measuring instrument, the output of which is a binary signal
[SOURCE: IEC 60770-1:2010, A.2 d), modified]
3.1.12
transmitter
instrument intended to transmit a standardized signal that represents the measured variable,
which may or may not include an integral sensing element
Note 1 to entry: A transmitter may also be equipped with the means to indicate a measured value.
Note 2 to entry: In process engineering a transmitter is often called a meter, for example flowmeter.
Note 3 to entry: A transmitter may also be a component of a composite device or measuring assembly.
3.2 Terms and definitions concerning relationships
3.2.1
aspect
specific way of selecting information on or describing a system or an object of a system
[SOURCE: IEC 61346-1:1996, 3.3]
EXAMPLE Such a way may be
– information about how to describe an object (device) – the describing aspect,
– information about the surrounding conditions in which a device operates – the operating aspect.
3.2.2
classification
non-transitive relationship indicating that the classified item is a member of the classifier class
[based on ISO 15926-2:2003]
EXAMPLE 1 The relationship that indicates that ‘London’ is a member of the class known as 'capital city' is known
as “classification”.
___________
This standard was withdrawn in 2009 and replaced by IEC/ISO 81346-1:2009 which has a more general
definition for aspect (3.3), namely “specified way of viewing an object”.

– 12 – 61987-11 © IEC:2012(E)
EXAMPLE 2 'pump' is_classified_as 'equipment type'.
Note 1 to entry: A subtype of relationship is transitive if when A is related to B, and B is related to C in the same
way, then A is necessarily related to C in that way. “Specialization” and “composition” are examples of transitive
subtypes of relationship. However, because classification is not transitive does not mean that A cannot be related
to C in the same way, only that it does not necessarily follow from A being related to B and B being related to C.
Note 2 to entry: In this document the classification relationship is denoted as: is_classified_as.
3.2.3
has_part
time-dependent transitive, reflexive, anti-symmetric relation identifying that an item has
another item as its part
EXAMPLE 1 Centrifugal pump has_part impeller during mounting.
Note 1 to entry: has_part is the inverse relation to is_part_of.
3.2.4
is_aspect_of
time-independent, anti-symmetric relation identifying that the LOP model of an aspect of a
device and the LOP model of the device are in relationship to each other, reflecting the
relationship between the device and its aspects
EXAMPLE The OLOP of a gauge is_aspect_of the DLOP of the gauge.
Note 1 to entry: IEC 61987-10 defines aspect as specific way of selecting information on or describing a system
or an object of a system.
3.2.5
is_part_of
time-dependent transitive, reflexive, anti-symmetric relation identifying that an item is part of
another item
EXAMPLE Impeller is_part_of centrifugal pump during mounting.
Note 1 to entry: C is_part_of C' if and only if: given any c that instantiates C at a time t, there is some c' such that
c' instantiates C' at time t, and c is_part_of c' at t.
Note 2 to entry: is_part_of is time-dependent. An item may be part of another item but will be disconnected later
during repair. In contrast the specialization and classification relation are time independent.
Note 3 to entry: The part of relation may be used on level of devices and on level of individual components.
However, only device level is in the scope of this standard since the standard does not deal with individuals.
3.2.6
specialization
transitive, anti-symmetric relation indicating that all knowledge provided for the generic item is
mandatory valid for the specialized item
EXAMPLE ‘Centrifugal pump’ is_a ‘pump’. All knowledge provided for ‘pump’ is mandatory valid for ‘centrifugal
pump’. If an individual is denoted as ‘centrifugal pump’, it is consequently also a ‘pump’ and all properties and
other information provided for ‘pump’ apply.
Note 1 to entry: If A is a specialization of B and B is a specialization of C, then A is necessarily a specialization
of C.
Note 2 to entry: In this part of standard the classification relationship is denoted as: is_a.
Note 3 to entry: If the generic item is a LOP then C is_a C' if and only if: given any c that instantiates C, c
instantiates C'
61987-11 © IEC:2012(E) – 13 –
4 General
4.1 Characterization scheme
IEC 61987-1 describes a general classification scheme for industrial process measuring
equipment based on measured variables. Industrial process measuring equipment may be
further subdivided into sight indicators, gauges, transmitters, switches and measuring
assemblies. See definitions in Clause 3. Figure 1 explains schematically how the
characterisation has been created. The entire characterisation is provided in Table A.1.
It should be noted that in creating the LOPs for a device, an instrument component may be
part of a sight indicator, gauge, transmitter or switch or alternatively, a sight indicator, gauge,
transmitter or switch may be part of a measuring assembly or composite device (see 7.1). For
clarity this is not shown in Figure 1.
The enhanced characterization scheme is used for the IEC Component Data Dictionary
(CDD). The area of measuring instruments belongs to the domain of “automation equipment”
in the CDD.
Measuring Instrument
MMeaeassururiingng I Insnsttrrumumeentnt
(M((MMeeeaasassuururirniingng Eg E Eqququiuipmipmpmeeentntnt) ))
iiss_c_cllasasssiiffiieded_as_as
SSSiiightghtght i i indindindicccatatatooorrr  GGGauauaugegege  TTTrrr  ansansansmmmiiittttttererer  SSSwiwiwitttccchhh
iiss__ccllaassssiiffiieded_as_as
LevLevLevelelel  FFFlllooowww  TTTememem  perperperatatatuuurrreee  PPPrereressssssuuurerere  DDDensensensiiitttyyy
.........
is_a
TTTypypyp  eee  111  TTTypypyp  eee  222
.........
is_a
SSSubtubtubtyyypppe 1.e 1.e 1.111  SSSubtubtubtyyypppe 1.e 1.e 1.222
.........
is_a
SSSecececononondadadarrryyy  SSSecececononondadadarrryyy
.........
sssubtubtubtyyypppeee 1. 1. 1.1.1.1.111  sssubtubtubtyyypppeee 1. 1. 1.1.1.1.222
is_a
...... ...... ...... IEC  1528/12

Figure 1 – Characterisation of measuring equipment
4.2 Aspects
In addition to properties describing the characterization of the device itself in the Device List
of Properties (DLOP) a device has several different aspects describing all other issues related
to it. Thus, for example, from the operating point of view, an operating list of properties
(OLOP) and a device list of properties are linked.
A.1 of IEC 61987-10:2009 describes a model which uses reference properties to express the
relationships between the various aspects of a device. This entails the embedding of these
properties in both the OLOP and DLOP. An alternative model which conforms to but enhances
that in A.1 of IEC 61987-10:2009, removes the reference properties from the OLOP and DLOP
as shown in Figure 2. These are now only required for describing the blocks and for building
composite devices.
– 14 – 61987-11 © IEC:2012(E)
Device type
Device type
specialisation
is_model_of
cardinality
11.*.*
LLOOPP ProProppeertrtyy
described_by
11.*.*
00.1.1
describes_device
__
feature
RRefefererenenccee
AAspspeectct BBlloockck
prproperoperttyy
11 00.*.*
00.*.*
describes_device_composition
ototherher t tyypepess
AALLOOPP CCLLOOPP OOLLOOPP DDLLOOPP
ofof LO LOPP
* * * *
11 11 11 11
is_aspect_of
is_aspect_of
is_aspect_of
is_aspect_of
IEC  1529/12
Figure 2 – Simplified UML scheme of device, LOPs and aspects
According to Figure 2, a device which belongs to a device type exists physically. The DLOP
provides a model of the device type, comprising blocks and properties, which represent the
device for electronic data exchange. The OLOP is an aspect of the device type which
describes the operating conditions under which it must or will operate. Since the DLOP
represents a concrete device, the OLOP is related to the DLOP by the “is_aspect_of”
relationship. The administrative LOP, the ALOP, contains the reference properties for the both
transaction and project, and provides the link between the DLOP and OLOP. Other aspects of
the DLOP are for example, LOPs for calibration and test, packaging documentation etc, see
Clause 8.
The use of aspects according to Figure 2 is advantageous, since it greatly simplifies the data
model when a device is composed of several components. In this case, the various aspects
can be used when needed and are not built-in to the LOPs as redundant properties.
Furthermore, the model can be extended by further aspects when they are required, e.g. for
intra-company use.
NOTE 1 In the context of this standard it is assumed that the DLOP and aspects of the same device type are
handled together within a single set of transaction data.
NOTE 2 A transaction starts by the transmission of the OLOP without the DLOP or vice versa together with an
ALOP, the other LOPs being added when required as the transaction proceeds.
NOTE 3 A list of aspects is to be found in Clause 8. Depending on the type of device and functions it supports,
other aspects may be required that are currently not included in this standard.
Summing up, the following can be stated:
• the DLOP is the essential part of a complete LOP concerning a device type;
• different aspects of a device type can be represented by corresponding LOP types;
• the combination of the DLOP with different aspects of a device type can be realized in two
ways
a) the connection of different LOP types for generation of a whole LOP using reference
properties as described in IEC 61987-10, or

61987-11 © IEC:2012(E) – 15 –
b) the connection of the DLOP with the required aspects of a device type using relationships
as introduced in this part of IEC 61987.
Approach a) can be used where fixed structures combining LOP types, for example an ALOP,
an OLOP and a DLOP, are needed. Approach b) is recommended in cases where the
description of reality by LOPs needs to be flexible.
4.3 Rules for the construction of LOPs with block structure
4.3.1 Block order
The order of blocks in a LOP as well as the order of sub-blocks and properties in a block shall
be fixed for depictions of the same LOP.
This means that the order given by the standard may not be altered. Practical experience has
shown that when working with LOPs comprising hundreds of lines (blocks and properties),
only this approach can guarantee that the contents of each block can be recognized.
The generic block structure of an Operating LOP given in Table 3 in 5.1 of this standard
defines the block order in an OLOP for measuring equipment.
The first structural level of a Device LOP for measuring equipment is defined in Clause 4 of
IEC 61987-1:2006, with the amendments described in 6.1.2 of this standard. Table 4 in 6.1.1
of this standard defines the generic block structure for a DLOP and includes additional levels.
4.3.2 Position of cardinality properties
In the representation of the structural data, the cardinality property, which determines how
many times a block should be repeated in the transaction file, shall be placed directly before
the block in the representation of the structural data.
NOTE Cardinality properties in the CDD can be recognized by the prefix “Number of ” and are
placed directly before the block with the .
4.3.3 Naming of blocks created by cardinality
Where a block is repeated in a LOP by using cardinality, the block name shall receive a suffix
comprising an underscore and an index indicative of the repeat.
EXAMPLE If the block "Signal function" is repeated twice, the two corresponding blocks in the transaction file are
given the names "Signal function_1" and "Signal function_2".
4.3.4 Characterizing property
Should the name of a
...

IEC 61987-11 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial-process measurement and control – Data structures and elements
in process equipment catalogues –
Part 11: List of Properties (LOP) of measuring equipment for electronic data
exchange – Generic structures
Mesure et contrôle des processus industriels – Structures de données et
éléments dans les catalogues d'équipement de processus –
Partie 11: Liste de propriétés (LOP) d'équipements de mesure pour échange de
données électronique – Structures génériques

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IEC 61987-11 ®
Edition 1.0 2012-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial-process measurement and control – Data structures and elements

in process equipment catalogues –

Part 11: List of Properties (LOP) of measuring equipment for electronic data

exchange – Generic structures
Mesure et contrôle des processus industriels – Structures de données et

éléments dans les catalogues d'équipement de processus –

Partie 11: Liste de propriétés (LOP) d'équipements de mesure pour échange de

données électronique – Structures génériques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 25.040.40; 35.100.20 ISBN 978-2-8322-1332-2

– 2 – 61987-11 © IEC:2012
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 10
3.1 Terms and definitions concerning measuring instruments . 10
3.2 Terms and definitions concerning relationships . 11
4 General . 13
4.1 Characterization scheme . 13
4.2 Aspects . 13
4.3 Rules for the construction of LOPs with block structure . 15
4.3.1 Block order . 15
4.3.2 Position of cardinality properties . 15
4.3.3 Naming of blocks created by cardinality . 15
4.3.4 Characterizing property . 15
4.3.5 Validity . 15
4.4 OLOP and DLOP . 15
4.5 Operating conditions . 16
4.6 Measuring equipment configuration . 17
5 Operating List of Properties (OLOP) . 18
5.1 Generic block structure . 18
5.2 Base conditions . 18
5.3 Process case . 19
5.3.1 General . 19
5.3.2 Process case variables . 19
5.3.3 Other process case variable . 20
5.4 Operating conditions for device design . 20
5.4.1 General . 20
5.4.2 Installation design conditions . 20
5.4.3 Environmental design conditions . 20
5.4.4 Process design conditions . 21
5.4.5 Pressure-temperature design conditions . 21
5.5 Process equipment . 22
5.5.1 General . 22
5.5.2 Line or equipment nozzle . 22
5.6 Physical location . 22
5.6.1 General . 22
5.6.2 Available power supply . 22
5.6.3 Process criticality classification . 23
5.6.4 Area classification . 23
6 Device list of properties (DLOP) . 23
6.1 General . 23
6.1.1 Generic block structure . 23
6.1.2 Relationship to IEC 61987-1 . 25
6.1.3 Multivariable devices . 25
6.2 Identification . 25

61987-11 © IEC:2012 – 3 –
6.3 Application . 26
6.4 Function and system design . 26
6.4.1 General . 26
6.4.2 Dependability . 26
6.5 Input . 26
6.5.1 General . 26
6.5.2 Measured variable . 26
6.5.3 Auxiliary input . 27
6.6 Output . 28
6.6.1 General . 28
6.6.2 output . 28
6.7 Digital communication . 29
6.7.1 General . 29
6.7.2 Digital communication interface . 29
6.8 Performance . 30
6.8.1 General . 30
6.8.2 Reference conditions for the device . 30
6.8.3 Performance variable. 30
6.9 Rated operating conditions . 32
6.9.1 General . 32
6.9.2 Installation conditions . 32
6.9.3 Environmental design ratings . 32
6.9.4 Process design ratings . 33
6.9.5 Pressure-temperature design ratings . 34
6.10 Mechanical and electrical construction . 34
6.10.1 General . 34
6.10.2 Overall dimensions and weight . 34
6.10.3 Structural design . 34
6.10.4 Explosion protection design approval . 34
6.10.5 Codes and standards approval . 34
6.11 Operability . 35
6.11.1 General . 35
6.11.2 Basic configuration . 35
6.11.3 Parametrization . 35
6.11.4 Adjustment . 35
6.11.5 Operation . 35
6.11.6 Diagnosis . 35
6.12 Power supply . 35
6.13 Certificates and approvals . 35
6.14 Component part identifications . 35
7 Composite devices . 36
7.1 Structure of composite devices . 36
7.2 Aspects of components . 37
8 Additional aspects . 38
8.1 Administrative information . 38
8.2 Calibration and test . 38
8.3 Accessories . 38
8.4 Device documents supplied . 38
8.5 Packaging and shipping. 39

– 4 – 61987-11 © IEC:2012
8.6 Digital communication parametrization . 39
8.7 Example of a composite device with aspects . 39
Annex A (normative) Device type dictionary – Classification of process measuring
equipment according to measuring characteristics . 40
Bibliography . 53

Figure 1 – Characterisation of measuring equipment . 13
Figure 2 – Simplified UML scheme of device, LOPs and aspects . 14
Figure 3 – Assignment of OLOPs and DLOPs for equipment used to measure one type
of measured variable . 16
Figure 4 – Structure of a composite device . 36
Figure 5 – Example for the structure of a LOP for a composite device showing different
aspects related to different sub-components . 39

Table 1 – Structure of the “Operating conditions for device design” block in the OLOP . 17
Table 2 – Structure of the “rated operating conditions” block in the DLOP . 17
Table 3 – Generic block structure of an OLOP . 18
Table 4 – Generic block structure of a DLOP . 24
Table 5 – DLOP structure for composite devices . 37
Table A.1 – Classification scheme for process measuring equipment . 40

61987-11 © IEC:2012 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL-PROCESS MEASUREMENT AND CONTROL –
DATA STRUCTURES AND ELEMENTS
IN PROCESS EQUIPMENT CATALOGUES –

Part 11: List of Properties (LOP) of measuring equipment
for electronic data exchange –
Generic structures
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61987-11 has been prepared by subcommittee 65E: Devices and
integration in enterprise systems, of IEC technical committee 65: Industrial-process
measurement, control and automation.
This bilingual version (2014-01) corresponds to the monolingual English version, published in
2012-07.
The text of this standard is based on the following documents:
FDIS Report on voting
65E/245/FDIS 65E/270/RVD
– 6 – 61987-11 © IEC:2012
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61987 series, published under the general title, Industrial-process
measurement and control – Data structures and elements in process equipment catalogues,
can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
61987-11 © IEC:2012 – 7 –
INTRODUCTION
0.1 General
The exchange of product data between companies, business systems, engineering tools, data
systems within companies and, in the future, control systems (electrical, measuring and
control technology) can run smoothly only when both the information to be exchanged and the
use of this information has been clearly defined.
Prior to this standard, requirements on process control devices and systems were specified by
customers in various ways when suppliers or manufacturers were asked to quote for suitable
equipment. The suppliers in their turn described the devices according to their own
documentation schemes, often using different terms, structures and media (paper, databases,
CDs, e-catalogues, etc.). The situation was similar in the planning and development process,
with device information frequently being duplicated in a number of different information
technology (IT) systems.
Any method that is capable of recording all existing information only once during the planning
and ordering process and making it available for further processing, gives all parties involved
an opportunity to concentrate on the essentials. A precondition for this is the standardization
of both the descriptions of the objects and the exchange of information.
This standard series proposes a method for standardization which will help both suppliers and
users of measuring equipment to optimize workflows within their own companies as well as in
their exchanges with other companies. Depending on their role in the process, engineering
firms may be considered here to be either users or suppliers.
The method specifies measuring equipment by means of blocks of properties. These blocks
are compiled into lists of properties (LOPs), each of which describes a specific equipment
(device) type. This standard series covers both properties that may be used in an inquiry or a
proposal and detailed properties required for integration of the equipment in computer
systems for other tasks.
IEC 61987-10 defines structure elements for constructing lists of properties for electrical and
process control equipment in order to facilitate automatic data exchange between any two
computer systems in any possible workflow, for example engineering, maintenance or
purchasing workflow and to allow both the customers and the suppliers of the equipment to
optimize their processes and workflows. Part 10 also provides the data model for assembling
the LOPs.
This part of the IEC 61987 series specifies the generic structure for operating and device lists
of properties (OLOPs and DLOPs). It lays down the framework for further parts of IEC 61987
in which complete LOPs for device types measuring a given physical variable and using a
particular measuring principle will be specified. The generic structure may also serve as a
basis for the specification of LOPs for other industrial-process control instrument types such
as control valves and signal processing equipment.
0.2 Content of the lists of properties (LOPs)
The LOPs specified in this standard describe at generic level:
• the operating conditions of the measuring equipment,
• the ambient conditions at the measuring point,
• the performance of the measuring equipment,
• the metrological, mechanical and electrical features of the measuring equipment,

– 8 – 61987-11 © IEC:2012
• the compliance of the measuring instrument to specific industrial requirements.
The LOPs mirror constructive reality but do not represent an instrument model.
0.3 Measuring equipment configuration
The generic LOPs have been so constructed that they take account of integral equipment and
separately mounted equipment.
0.4 Device type dictionary
Annex A of this part describes a characterisation of measuring equipment based on the STEP
library, ISO 10303. This is a tree of relationships between different device types. Starting at
the root “automation equipment”, it first characterizes measuring equipment according to type,
then according to process variable measured and finally according to the measuring method
employed. This structure will be used in the IEC Component Data Dictionary (CDD)
“Automation equipment” Domain.
For the purpose of this standard the following types of measuring equipment have been
identified and defined in Clause 3: sight indicator, gauge, transmitter, switch and measuring
assembly.
It should be noted that in the real world, there is not such a clear demarcation between types
of measuring equipment. In commercial literature indicators are often called gauges, although
the products offer no quantitative measurement. Similarly, direct indicating displays are often
equipped with electrical trip switches which allow a gauge to act as a switch. Finally,
“transmitter” is by no means a universal term and in particular for flow measurement many
manufacturers call this kind of equipment “meter”.
0.5 Composite devices
A structural scheme is given, defining how to build up LOPs for devices consisting of several
components or assembled from different parts, that is, composite devices and measuring
assemblies.
61987-11 © IEC:2012 – 9 –
INDUSTRIAL-PROCESS MEASUREMENT AND CONTROL –
DATA STRUCTURES AND ELEMENTS
IN PROCESS EQUIPMENT CATALOGUES –

Part 11: List of Properties (LOP) of measuring equipment
for electronic data exchange –
Generic structures
1 Scope
This part of IEC 61987 provides
• a characterisation of industrial process measuring equipment (device type dictionary) for
integration in the Component Data Dictionary (CDD), and
• generic structures for Operating Lists of Properties (OLOPs) and Device Lists of
Properties (DLOPs) of measuring equipment in conformance with IEC 61987-10.
The generic structures for the OLOPs and DLOPs contain the most important blocks for
process measuring equipment. Blocks pertaining to a specific equipment type will be
described in the corresponding part of the IEC 61987 series (for example IEC 61987-12, flow
transmitters). Similarly, equipment properties are not dealt with in this part of the series For
instance, the OLOPs and DLOPs for flow transmitters with blocks and properties will be found
in future in IEC 61987-12.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 61069-5, Industrial-process measurement and control – Evaluation of system properties
for the purpose of system assessment – Part 5: Assessment of system dependability
IEC 61508-6, Functional safety of electrical/electronic/programmable electronic safety-related
systems – Part 6: Guidelines on the application of IEC 61508-2 and IEC 61508-3
IEC 61987 (all parts), Industrial-process measurement and control – Data structures and
elements in process equipment catalogues
IEC 61987-1:2006, Industrial-process measurement and control – Data structures and
elements in process equipment catalogues – Part 1: Measuring equipment with analog and
digital output
IEC 61987-10:2009 Industrial-process measurement and control – Data structures and
elements in process equipment catalogues – Part 10: Lists of Properties (LOPs) for Industrial-
Process Measurement and Control for Electronic Data Exchange – Fundamentals
IEC 62424, Representation of process control engineering – Requests in P&I diagrams and
data exchange between P&ID tools and PCE-CAE tools

– 10 – 61987-11 © IEC:2012
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Terms and definitions concerning measuring instruments
3.1.1
composite device with main component
device composed of various devices, whereby one is designated the main component
Note 1 to entry: These devices might be supplied as a whole or the parts comprising the assembly of the
composite device might be supplied individually.
EXAMPLE A control valve which consists of the valve itself (main component), an actuator and a positioner.
3.1.2
gauge
measuring instrument intended to measure and indicate directly a measured value without
auxiliary energy supply
Note 1 to entry: In process engineering a gauge is often called an indicator.
Note 2 to entry: A gauge equipped with electrical contacts in order to transmit one or more measured values to
external equipment is still considered to be a gauge within the scope of this standard.
3.1.3
instrument component
entity within an instrument that plays a specific role and which can be handled separately if
necessary
EXAMPLES Thermowell within a temperature assembly, remote seal for a pressure transmitter.
3.1.4
integral transmitter
transmitter mounted as an integral part of an assembly containing the sensing element
3.1.5
measuring assembly
measuring instrument comprising several required and/or optional components which together
function as a gauge, transmitter or switch
Note 1 to entry: The components can often be ordered separately and as such require their own DLOPs.
Note 2 to entry: A measuring assembly may also be called a composite device.
3.1.6
measuring instrument
artefact intended to detect an aspect of a material to record, transform or display such an
aspect or to perform a combination of these activities
3.1.7
PCE identifier
tag name
identifier assigned by the user to uniquely define the instrument or a component thereof
Note 1 to entry: PCE = Process Control Engineering.

61987-11 © IEC:2012 – 11 –
3.1.8
sensing element
instrument component that is the primary element of a measuring chain and which may
convert the input variable into a signal suitable for use by other instruments in that chain
Note 1 to entry: It is intended to respond to a physical stimulus and to produce a corresponding resulting signal.
3.1.9
separate transmitter
transmitter mounted at a location removed (locally or remotely) from an assembly containing
the sensing element but connected to it by signal line
Note 1 to entry: A head-mounted transmitter is a separate transmitter mounted in a connection head.
3.1.10
sight indicator
measuring instrument that provides a means of visually inspecting a process regime and
provides only a qualitative indication
Note 1 to entry: IEC 60770-1 defines “indicator” as an instrument intended to visually indicate a physical quantity.
3.1.11
switch
measuring instrument, the output of which is a binary signal
[SOURCE: IEC 60770-1:2010, A.2 d), modified]
3.1.12
transmitter
instrument intended to transmit a standardized signal that represents the measured variable,
which may or may not include an integral sensing element
Note 1 to entry: A transmitter may also be equipped with the means to indicate a measured value.
Note 2 to entry: In process engineering a transmitter is often called a meter, for example flowmeter.
Note 3 to entry: A transmitter may also be a component of a composite device or measuring assembly.
3.2 Terms and definitions concerning relationships
3.2.1
aspect
specific way of selecting information on or describing a system or an object of a system
[SOURCE: IEC 61346-1:1996, 3.3]
EXAMPLE Such a way may be
– information about how to describe an object (device) – the describing aspect,
– information about the surrounding conditions in which a device operates – the operating aspect.
3.2.2
classification
non-transitive relationship indicating that the classified item is a member of the classifier class
[based on ISO 15926-2:2003]
EXAMPLE 1 The relationship that indicates that ‘London’ is a member of the class known as 'capital city' is known
as “classification”.
___________
This standard was withdrawn in 2009 and replaced by IEC/ISO 81346-1:2009 which has a more general
definition for aspect (3.3), namely “specified way of viewing an object”.

– 12 – 61987-11 © IEC:2012
EXAMPLE 2 'pump' is_classified_as 'equipment type'.
Note 1 to entry: A subtype of relationship is transitive if when A is related to B, and B is related to C in the same
way, then A is necessarily related to C in that way. “Specialization” and “composition” are examples of transitive
subtypes of relationship. However, because classification is not transitive does not mean that A cannot be related
to C in the same way, only that it does not necessarily follow from A being related to B and B being related to C.
Note 2 to entry: In this document the classification relationship is denoted as: is_classified_as.
3.2.3
has_part
time-dependent transitive, reflexive, anti-symmetric relation identifying that an item has
another item as its part
EXAMPLE 1 Centrifugal pump has_part impeller during mounting.
Note 1 to entry: has_part is the inverse relation to is_part_of.
3.2.4
is_aspect_of
time-independent, anti-symmetric relation identifying that the LOP model of an aspect of a
device and the LOP model of the device are in relationship to each other, reflecting the
relationship between the device and its aspects
EXAMPLE The OLOP of a gauge is_aspect_of the DLOP of the gauge.
Note 1 to entry: IEC 61987-10 defines aspect as specific way of selecting information on or describing a system
or an object of a system.
3.2.5
is_part_of
time-dependent transitive, reflexive, anti-symmetric relation identifying that an item is part of
another item
EXAMPLE Impeller is_part_of centrifugal pump during mounting.
Note 1 to entry: C is_part_of C' if and only if: given any c that instantiates C at a time t, there is some c' such that
c' instantiates C' at time t, and c is_part_of c' at t.
Note 2 to entry: is_part_of is time-dependent. An item may be part of another item but will be disconnected later
during repair. In contrast the specialization and classification relation are time independent.
Note 3 to entry: The part of relation may be used on level of devices and on level of individual components.
However, only device level is in the scope of this standard since the standard does not deal with individuals.
3.2.6
specialization
transitive, anti-symmetric relation indicating that all knowledge provided for the generic item is
mandatory valid for the specialized item
EXAMPLE ‘Centrifugal pump’ is_a ‘pump’. All knowledge provided for ‘pump’ is mandatory valid for ‘centrifugal
pump’. If an individual is denoted as ‘centrifugal pump’, it is consequently also a ‘pump’ and all properties and
other information provided for ‘pump’ apply.
Note 1 to entry: If A is a specialization of B and B is a specialization of C, then A is necessarily a specialization
of C.
Note 2 to entry: In this part of standard the classification relationship is denoted as: is_a.
Note 3 to entry: If the generic item is a LOP then C is_a C' if and only if: given any c that instantiates C, c
instantiates C'
61987-11 © IEC:2012 – 13 –
4 General
4.1 Characterization scheme
IEC 61987-1 describes a general classification scheme for industrial process measuring
equipment based on measured variables. Industrial process measuring equipment may be
further subdivided into sight indicators, gauges, transmitters, switches and measuring
assemblies. See definitions in Clause 3. Figure 1 explains schematically how the
characterisation has been created. The entire characterisation is provided in Table A.1.
It should be noted that in creating the LOPs for a device, an instrument component may be
part of a sight indicator, gauge, transmitter or switch or alternatively, a sight indicator, gauge,
transmitter or switch may be part of a measuring assembly or composite device (see 7.1). For
clarity this is not shown in Figure 1.
The enhanced characterization scheme is used for the IEC Component Data Dictionary
(CDD). The area of measuring instruments belongs to the domain of “automation equipment”
in the CDD.
Measuring Instrument
MMeaeassururiingng I Insnsttrrumumeentnt
(M((MMeeeaasassuururirniingng Eg E Eqququiuipmipmpmeeentntnt) ))
iiss_c_cllasasssiiffiieded_as_as
SSSiiightghtght i i indindindicccatatatooorrr  GGGauauaugegege  TTTrrr  ansansansmmmiiittttttererer  SSSwiwiwitttccchhh
iiss__ccllaassssiiffiieded_as_as
LevLevLevelelel  FFFlllooowww  TTTememem  perperperatatatuuurrreee  PPPrereressssssuuurerere  DDDensensensiiitttyyy
.........
is_a
TTTypypyp  eee  111  TTTypypyp  eee  222
.........
is_a
SSSubtubtubtyyypppe 1.e 1.e 1.111  SSSubtubtubtyyypppe 1.e 1.e 1.222
.........
is_a
SSSecececononondadadarrryyy  SSSecececononondadadarrryyy
.........
sssubtubtubtyyypppeee 1. 1. 1.1.1.1.111  sssubtubtubtyyypppeee 1. 1. 1.1.1.1.222
is_a
...... ...... ...... IEC  1528/12

Figure 1 – Characterisation of measuring equipment
4.2 Aspects
In addition to properties describing the characterization of the device itself in the Device List
of Properties (DLOP) a device has several different aspects describing all other issues related
to it. Thus, for example, from the operating point of view, an operating list of properties
(OLOP) and a device list of properties are linked.
A.1 of IEC 61987-10:2009 describes a model which uses reference properties to express the
relationships between the various aspects of a device. This entails the embedding of these
properties in both the OLOP and DLOP. An alternative model which conforms to but enhances
that in A.1 of IEC 61987-10:2009, removes the reference properties from the OLOP and DLOP
as shown in Figure 2. These are now only required for describing the blocks and for building
composite devices.
– 14 – 61987-11 © IEC:2012
Device type
Device type
specialisation
is_model_of
cardinality
11.*.*
LLOOPP ProProppeertrtyy
described_by
11.*.*
00.1.1
describes_device
__
feature
RRefefererenenccee
AAspspeectct BBlloockck
prproperoperttyy
11 00.*.*
00.*.*
describes_device_composition
ototherher t tyypepess
AALLOOPP CCLLOOPP OOLLOOPP DDLLOOPP
ofof LO LOPP
* * * *
11 11 11 11
is_aspect_of
is_aspect_of
is_aspect_of
is_aspect_of
IEC  1529/12
Figure 2 – Simplified UML scheme of device, LOPs and aspects
According to Figure 2, a device which belongs to a device type exists physically. The DLOP
provides a model of the device type, comprising blocks and properties, which represent the
device for electronic data exchange. The OLOP is an aspect of the device type which
describes the operating condit
...