EN 60770-3:2014

SLOVENSKI STANDARD
01-december-2014
Oddajniki za uporabo v sistemih vodenja industrijskih procesov - 3. del: Metode
vrednotenja lastnosti inteligentnih oddajnikov (IEC 60770-3:2014)
Transmitters for use in industrial-process control systems - Part 3: Methods for
performance evaluation of intelligent transmitters (IEC 60770-3:2014)
Messumformer für industrielle Prozessleittechnik - Teil 3: Verfahren zur Bewertung der
Leistungsfähigkeit von intelligenten Messumformern (IEC 60770-3:2014)
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Ta slovenski standard je istoveten z: EN 60770-3:2014
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 60770-3
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2014
ICS 25.040.40 Supersedes EN 60770-3:2006
English Version
Transmitters for use in industrial-process control systems - Part
3: Methods for performance evaluation of intelligent transmitters
(IEC 60770-3:2014)
Transmetteurs utilisés dans les systèmes de commande Messumformer für industrielle Prozessleittechnik - Teil 3:
des processus industriels - Partie 3: Méthodes d'évaluation Verfahren zur Bewertung der Leistungsfähigkeit von
des performances des transmetteurs intelligents intelligenten Messumformern
(CEI 60770-3:2014) (IEC 60770-3:2014)
This European Standard was approved by CENELEC on 2014-06-27. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 60770-3:2014 E
Foreword
The text of document 65B/917/FDIS, future edition 2 of IEC 60770-3, prepared by SC 65B
“Measurement and control devices” of IEC/TC 65 “Industrial-process measurement, control and
automation” was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be (dop) 2015-03-27
implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2017-06-27
• latest date by which the national
standards conflicting with the
document have to be withdrawn
This document supersedes EN 60770-3:2006.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 60770-3:2014 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:

IEC 60068-2-1 NOTE Harmonized as EN 60068-2-1.
IEC 60068-2-2 NOTE Harmonized as EN 60068-2-2.
IEC 60068-2-6 NOTE Harmonized as EN 60068-2-6.
IEC 60068-2-31 NOTE Harmonized as EN 60068-2-31.
IEC 60068-2-78 NOTE Harmonized as EN 60068-2-78.
IEC 60654 Series NOTE Harmonized as EN 60654 Series (not modified).
IEC 61298 Series NOTE Harmonized as EN 61298 Series (not modified).
IEC 61508 Series NOTE Harmonized as EN 61508 Series (not modified).

- 3 - EN 60770-3:2014
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.

NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu
Publication Year Title EN/HD Year

IEC 60050 Series International Electrotechnical Vocabulary - -
(IEV)
IEC 60381 Series Analogue signals for process control HD 452.1 S1
systems
IEC 60529 -  Degrees of protection provided by EN 60529 -
enclosures (IP Code)
IEC 60721-3 Series Classification of environmental EN 60721-3 Series
conditions -
Part 3: Classification of groups of
environmental parameters and their
severities
IEC 61010-1 -  Safety requirements for electrical EN 61010-1 -
equipment for measurement, control and
laboratory use -
Part 1: General requirements
IEC 61032 -  Protection of persons and equipment by EN 61032 -
enclosures - Probes for verification
IEC 61158 Series Industrial communication networks - EN 61158 Series
Fieldbus specifications
IEC 61298 Series Process measurement and control EN 61298 Series
devices - General methods
and procedures for evaluating
performance
IEC 61298-1 2008 Process measurement and control EN 61298-1 2008
devices - General methods
and procedures for evaluating
performance -
Part 1: General considerations
IEC 61298-2 2008 Process measurement and control EN 61298-2 2008
devices - General methods
and procedures for evaluating
performance -
Part 2: Tests under reference conditions

IEC 61298-3 2008 Process measurement and control EN 61298-3 2008
devices - General methods
and procedures for evaluating
performance -
Part 3: Tests for the effects of influence
quantities
IEC 61298-4 - Process measurement and control EN 61298-4 -
devices - General methods
and procedures for evaluating
performance -
Part 4: Evaluation report content
IEC 61326 Series Electrical equipment for measurement, EN 61326 Series
control and laboratory use -
EMC requirements
IEC 61326-1 -  Electrical equipment for measurement, EN 61326-1 -
control and laboratory use -
EMC requirements -
Part 1: General requirements
IEC 61499 Series Function blocks EN 61499 Series
IEC 61804 Series Function Blocks (FB) for process control EN 61804 Series
CISPR 11 -  Industrial, scientific and medical EN 55011 -
equipment - Radio-frequency disturbance
characteristics - Limits and methods of
measurement
IEC 60770-3 ®
Edition 2.0 2014-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Transmitters for use in industrial-process control systems –

Part 3: Methods for performance evaluation of intelligent transmitters

Transmetteurs utilisés dans les systèmes de commande des processus

industriels –
Partie 3: Méthodes d’évaluation des performances des transmetteurs intelligents

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XA
ICS 25.040.40 ISBN 978-2-8322-1629-3

– 2 – IEC 60770-3:2014 © IEC 2014
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Design assessment . 10
4.1 General . 10
4.2 Transmitter analysis . 11
4.2.1 General . 11
4.2.2 Data processing subsystem. 12
4.2.3 Sensor subsystem. 12
4.2.4 Human interface . 13
4.2.5 Communication interface . 13
4.2.6 Electrical output subsystem . 13
4.2.7 Power supply unit . 14
4.2.8 External functionality . 14
4.2.9 Cycle times (ct) . 14
4.3 Aspects to be reviewed . 14
4.3.1 General . 14
4.3.2 Functionality . 15
4.3.3 Configurability . 16
4.3.4 Hardware configuration . 17
4.3.5 Adjustment and tuning . 18
4.3.6 Operability . 19
4.3.7 Dependability . 20
4.3.8 Manufacturer's support . 21
4.3.9 Reporting . 22
4.4 Documentary information . 22
5 Performance testing . 23
5.1 General . 23
5.2 Instrument considerations . 23
5.2.1 General . 23
5.2.2 Example of a single variable transmitter . 24
5.2.3 Example of a derived variable transmitter . 24
5.3 Measurement considerations . 25
5.3.1 General . 25
5.3.2 Single variables . 25
5.3.3 Derived variable . 26
5.4 Test facilities . 26
5.4.1 General . 26
5.4.2 Signal generator . 27
5.4.3 Output load/receiver . 27
5.4.4 Control and data acquisition . 28
5.5 Transmitter under test (testing precautions) . 28
5.6 Reference conditions for performance tests . 28
5.7 Test procedures for tests under reference conditions . 29

IEC 60770-3:2014 © IEC 2014 – 3 –
5.8 Test procedures for determination of the effects of influence quantities . 32
5.8.1 General . 32
5.8.2 Process domain . 34
5.8.3 Utility domain . 39
5.8.4 Environmental domain . 41
5.8.5 Time domain . 43
6 Other considerations . 43
6.1 Safety . 43
6.2 Degree of protection provided by enclosures . 43
6.3 Electromagnetic emission . 44
6.4 Variants . 44
7 Evaluation report. 44
Annex A (informative) Dependability testing . 45
A.1 General . 45
A.2 Design analysis . 45
A.3 Reference conditions . 45
A.4 Fault injection test for internal instrument failures . 47
A.5 Observations . 47
A.5.1 General . 47
A.5.2 Reporting and ranking of fault behaviour . 48
A.6 Human faults . 50
A.6.1 Mis-operation test . 50
A.6.2 Maintenance error test . 51
A.6.3 Expectations and reporting . 51
Annex B (informative) Throughput testing . 52
B.1 General . 52
B.2 Transmitter throughput (stand-alone) . 53
B.2.1 Reference conditions . 53
B.2.2 Test conditions . 53
B.2.3 Observations and measurements . 54
B.3 Throughput in a fieldbus configuration . 54
B.3.1 Reference conditions . 54
B.3.2 Test conditions . 54
B.3.3 Observations and measurements . 55
B.3.4 Precautions. 55
Annex C (informative) Function block testing . 56
C.1 General . 56
C.2 General qualitative checks . 56
C.3 Time-dependent function blocks . 56
C.4 Time-independent function blocks . 56
Bibliography . 57

Figure 1 – Intelligent transmitter model . 12
Figure 2 – Basic test set-up . 27
Figure 3 – Examples of step responses of electrical outputs of transmitters . 31
Figure A.1 – Example schematic of a transmitter . 46
Figure A.2 – Test tool for low impedance circuits and shared circuits . 47

– 4 – IEC 60770-3:2014 © IEC 2014
Figure A.3 – Matrix for reporting fault behaviour . 49
Figure A.4 – Ranking of various types of failure modes . 50
Figure B.1 – Transmitter in stand-alone configuration . 52
Figure B.2 – Transmitter as a participant in a fieldbus installation . 53

Table 1 – Checklist for mapping functionality . 15
Table 2 – Checklist for mapping configurability . 16
Table 3 – Checklist for mapping hardware-configuration . 17
Table 4 – Checklist for mapping adjustment and tuning procedures . 18
Table 5 – Checklist for mapping operability . 19
Table 6 – Checklist for mapping dependability . 20
Table 7 – Checklist for mapping manufacturer’s support . 21
Table 8 – Reporting format for design review . 22
Table 9 – Checklist on available documentation . 22
Table 10 – Listing of functions of a single variable transmitter. 24
Table 11 – Listing of functions of derived variable transmitter . 25
Table 12 – Reference environmental and operational test conditions . 29
Table 13 – Procedures for tests under reference conditions . 29
Table 14 – Methods for testing immunity to sensor disturbances – Matrix of instrument
properties and tests . 35
Table 15 – Methods for testing immunity to wiring disturbances . 37
Table 16 – Methods for testing the immunity to disturbances of the power utilities . 39
Table 17 – Methods for testing the immunity to environmental disturbances . 41
Table 18 – Methods for testing the immunity to degradation in time . 43

IEC 60770-3:2014 © IEC 2014 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
TRANSMITTERS FOR USE IN INDUSTRIAL-PROCESS
CONTROL SYSTEMS –
Part 3: Methods for performance evaluation
of intelligent transmitters
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC 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.
The International Standard IEC 60770-3 has been prepared by subcommittee 65B:
Measurement and control devices, of IEC technical committee 65: Industrial-process
measurement, control and automation.
This second edition cancels and replaces the first edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Introduction.
b) Terms and definitions: all definitions already present in IEC 60050 and in IEC 61298 have
been deleted.
c) All parts: added concept of wireless transmitters.

– 6 – IEC 60770-3:2014 © IEC 2014
The text of this standard is based on the following documents:
FDIS Report on voting
65B/917/FDIS 65B/930/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60770, published under the general title Transmitters for use in
industrial-process control systems, 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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

IEC 60770-3:2014 © IEC 2014 – 7 –
INTRODUCTION
New transmitters for use in industrial process control systems are now equipped with micro-
processors which utilise digital data processing and communication methods, auxiliary sensors
and artificial intelligence. This makes them more complex than conventional analogue
transmitters and gives them considerable added value.
An intelligent transmitter is an instrument that uses digital data processing and communication
methods for performing its functions and for safeguarding and communicating data and
information on its operation. It may be equipped with additional sensors and functionality which
support the main function of the intelligent transmitter. The variety of added functionality can
for instance enhance accuracy and rangeability, self-test capabilities, and alarm and condition
monitoring. Therefore accuracy-related performance testing, although still a major tool for
evaluation, is no longer sufficient to show the flexibility, capability and other features with
respect to engineering, installation, maintainability, reliability and operability.
Because of the complexity of intelligent transmitters, a close collaboration should be
maintained between the evaluating body and the manufacturer during the evaluation. Note
should be taken of the manufacturer's specifications for the instrument, when the test
programme is being decided, and the manufacturer should be invited to comment on both the
test programme and the results. His comments on the results should be included in any report
produced by the testing organisation.
This part of IEC 60770 addresses, in its main body, structured and mandatory methods for a
design review and performance testing of intelligent transmitters. Intelligent transmitters will, in
many cases, also have the capacity to be integrated into digital communication (bus) systems,
where they have to co-operate with a variety of devices. In this case, dependability,
(inter)operability and real-time behaviour are important issues. The testing of these aspects
depends largely on the internal structure and organisation of the intelligent transmitter and the
architecture and size of the bus system. The Annexes A, B and C give a non-mandatory
methodology and framework for designing specific evaluation procedures for dependability and
throughput testing and function block testing in a specific case.
When a full evaluation, in accordance with this part of IEC 60770, is not required or possible,
those tests which are required, should be performed and the results reported in accordance
with the relevant parts of this standard. In such cases, the test report should state that it does
not cover the full number of tests specified herein. Furthermore, the items omitted should be
mentioned, in order to give the reader of the report a clear overview.
The structure of this part of IEC 60770 largely follows the framework of IEC 62098. For
performance testing, the IEC 61298 series should also be consulted. A number of tests
described there are still valid for intelligent transmitters. Further reading of the IEC 61069
series is recommended, as some notions in this part of IEC 60770 are based on concepts
brought forward therein.
– 8 – IEC 60770-3:2014 © IEC 2014
TRANSMITTERS FOR USE IN INDUSTRIAL-PROCESS
CONTROL SYSTEMS –
Part 3: Methods for performance evaluation
of intelligent transmitters
1 Scope
This part of IEC 60770 specifies the following methods.
• Methods for
– assessment of the functionality of intelligent transmitters;
– testing the operational behaviour, as well as the static and dynamic performance of an
intelligent transmitter.
• Methodologies for
– determining the reliability and diagnostic features used to detect malfunctions;
– determining the communication capabilities of the intelligent transmitters in a
communication network.
The methods and methodologies are applicable to intelligent transmitters, which convert one or
more physical, chemical or electrical quantities into digital signals for use in a communication
network (as specified in the IEC 61158 series or others) or into analogue electrical signals (as
specified in the IEC 60381 series).
The methods and methodologies listed in this part of IEC 60770 are intended for use by:
– manufacturers to determine the performance of their products, and
– users or independent testing laboratories to verify equipment performance specifications.
Manufacturers of intelligent transmitters are urged to apply this part of IEC 60770 at an early
stage of development.
This standard is intended to provide guidance for designing evaluations of intelligent
transmitters by providing:
– a checklist for reviewing the hardware and software design in a structured way;
– test methods for measuring and qualifying the performance, dependability and operability
under various environmental and operational conditions;
– methods for reporting the data obtained.
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 60050 (all parts), International Electrotechnical Vocabulary (available at
http://www.electropedia.org)
IEC 60381 (all parts), Analogue signals for process control systems
IEC 60529, Degree of protection provided by enclosures (IP Code)

IEC 60770-3:2014 © IEC 2014 – 9 –
IEC 60721-3 (all parts), Classification of environmental conditions – Part 3: Classification of
groups of environmental parameters and their severities
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
IEC 61032, Protection of persons and equipment by enclosures – Probes for verification
IEC 61158 (all parts), Industrial communication networks – Fieldbus specifications
IEC 61298 (all parts), Process measurement and control devices – General methods and
procedures for evaluating performance
IEC 61298-1:2008, Process measurement and control devices – General methods and
procedures for evaluating performance – Part 1: General considerations
IEC 61298-2:2008, Process measurement and control devices – General methods and
procedures for evaluating performance – Part 2: Tests under reference conditions
IEC 61298-3:2008, Process measurement and control devices – General methods and
procedures for evaluating performance – Part 3: Tests for the effects of influence quantities
IEC 61298-4, Process measurement and control devices – General methods and procedures
for evaluating performance – Part 4: Evaluation report content
IEC 61326 (all parts), Electrical equipment for measurement, control and laboratory use – EMC
requirements
IEC 61326-1, Electrical equipment for measurement, control and laboratory use – EMC
requirements – Part 1: General requirements
IEC 61499 (all parts), Function blocks
IEC 61804 (all parts), Function blocks (FB) for process control
CISPR 11, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-300, in the
IEC 61298 series and the following apply.
3.1
intelligent transmitter
transmitter provided with means for bi-directional communication with external systems and
human operators for sending measurement and status information and receiving and
processing external commands
3.2
single variable transmitter
transmitter that measures one single physical quantity

– 10 – IEC 60770-3:2014 © IEC 2014
3.3
multivariable transmitter
transmitter that measures two or more identical or different physical quantities
3.4
adjustment
set of operations carried out on a measuring instrument in order that it provides given
indications corresponding to given values of the measurand
Note 1 to entry: When the instrument is made to give a null indication corresponding to a null value of the
measurand, the set of operations is called zero adjustment.
Note 2 to entry: Many manufacturers use the term calibration for adjustment of zero, span and linearity or
conformity.
3.5
tuning
process of adjusting the various instrument parameters, required for obtaining a stable and
optimal measurement
Note 1 to entry: This can range from "trial and error" to an automatic proprietary procedure provided by the
manufacturer.
3.6
configuring
process of implementing the functionality required for a certain application
3.7
configurability
extent to which an intelligent transmitter can be provided with functions to control various
applications
3.8
set-up
process of configuring, calibrating and tuning a transmitter for optimal measurement
3.9
operating mode
selected method of operation of a transmitter
4 Design assessment
4.1 General
The design review is meant to identify and make explicit, in a structured way, the functionality
and capabilities of the intelligent transmitter under consideration. As stated in the introduction,
intelligent transmitters appear in a great variety of designs. A design review is the necessary
tool for showing the details of:
– the physical structure,
– the functional structure.
Subclause 4.2 guides the evaluator through the process of describing the physical structure of
intelligent transmitters by identifying the hardware modules and the inputs and outputs to the
operational and environmental domains. Thereafter, the functional structure can be described,
using the checklist of 4.3. The checklist gives a framework of the relevant issues, which need
to be addressed by the evaluator, mainly through adequate qualitative and quantitative
experiments.
IEC 60770-3:2014 © IEC 2014 – 11 –
4.2 Transmitter analysis
4.2.1 General
Two different types of transmitters can be identified:
• Single variable transmitter. The measured value (output) represents one single physical
quantity measured by one type of sensor.
• Multivariable transmitter. This type of transmitters appears in two versions:
– An instrument providing a variety of measured values (outputs), each of which is related
to a measurement of one distinct input quantity with a specific sensor.
– An instrument providing derived measured values resulting from the measurement of
more than one quantity through more than one type of sensor and processed through a
distinct algorithm (e.g. flow computer, mechanical power meter). In many cases, the
individual measured variables are also available to the user.
Each type of intelligent transmitter may be equipped with independent auxiliary sensors and
auxiliary (mainly digital) outputs, which are not involved in the primary measurement process.
The generic transmitter model of Figure 1 gives a maximum configuration and is a tool for
setting up a block scheme and concise description of the transmitter to be evaluated. It is also
important for defining the functions to be considered in the performance tests (see Clause 5).
Functionally, a transmitter is an information transformer. Data enters and then exits the
instrument through the various (external) domains given in Figure 1, following distinct data flow
paths. The following paths can be defined, but are not always resident in a specific transmitter
under consideration:
• Sensors (process domain) to external systems (remote data processing systems).
• Sensors (process domain) to operator displays (human domain).
• Sensors (process domain) to external systems (electrical outputs).
• Operator commands through local keyboard (human domain) to data processing
subsystem, consequently affecting the above-mentioned data flows to external systems
(remote data processing systems and electrical outputs).
• Remote commands (from external remote data processing systems) to the instrument’s
data processing subsystem, consequently affecting the above-mentioned data flows to
external systems (electrical outputs) and local operator displays (human domain).
A block scheme and description shall be included in the evaluation report and may be
enhanced with photographs or drawings of important details.

– 12 – IEC 60770-3:2014 © IEC 2014

Utility domain
Supply voltage
ct
To external system
External system domain
Power supply
Communication
unit
interface
Analog
output (mA)
Main sensor(s)
ct
Data
Electrical
Sensor Digital
processing
output
communication
subsystem
Auxiliary sensors
subsystem
subsystem
ct
Binary
output (relay)
ct
Process domain
Human
interface
To human operator
Human domain
IEC  1827/14
Key
ct cycle time
Figure 1 – Intelligent transmitter model
For an intelligent transmitter, the main physical modules and provisions for connection to
external systems and human operators are defined in 4.2.2 to 4.2.9.
4.2.2 Data processing subsystem
The data processing subsystem is the heart of an intelligent transmitter. Its main function is to
provide and process the measured quantity(ies) for further real-time use by the human and
communication interfaces and/or at the electrical output subsystem. Many transmitters
measure one quantity by means of one (main) sensor, but derived measured values such as
heat or mass flow and mechanical power require more sensors.
Besides the main measurement function, a transmitter may be equipped with a number of
additional functions that can vary considerably from make to make. Amongst the additional
functions that may be resident in a transmitter are:
– configuration;
– adjustment and tuning;
– self-testing, diagnostics, condition monitoring;
– external process control function;
– trending and data storage.
Part of the functionality may be located in external devices that are temporarily or continuously
connected to the communication interface (e.g. configuring, trending).
4.2.3 Sensor subsystem
The sensor subsystem converts the physical or chemical quantity(ies) to be measured into
electrical signals that are conditioned and digitised for use by the data processing unit. The
subsystem may also be equipped with electrical circuits for sensing binary signals (e.g. change

IEC 60770-3:2014 © IEC 2014 – 13 –
measurement range on an external command), or auxiliary sensors of a different type (e.g.
auxiliary for compensation or internal diagnostics and condition monitoring purposes).
The sensor and sensor subsystem may be integrated with the other modules in one enclosure.
The sensor can also be located remotely (e.g. densitometer, thermocouple transmitter). Certain
transmitters (e.g. thermocouple and resistance thermometer detector (RTD)) utilise
standardised (third party) sensors that provide an electric signal. In such a case, it may be
agreed to perform the evaluation with an acceptable simulator instead of the application of the
actual quantity.
Depending on the measurement principle used, the sensor may not require auxiliary (external)
power (e.g. thermocouples) or it may require auxiliary power (e.g. strain gauges) or a
specifically characterised power source (e.g. electromagnetic and Coriolis flowmeters).
Sensors are, in general, incorporated in the process installations and in many cases, they may
also be in direct contact with the process medium. As such, medium properties, medium
conditions and installation conditions may adversely influence them. As a remote unit, the
sensor may also be subjected to more severe environmental conditions than the other
subsystems. Moreover, it shall also be considered whether it is necessary to apply combined
environmental and process conditions during an evaluation.
As part of the design review, a list of the types of sensors that are provided and their
measuring ranges shall be compiled.
4.2.4 Human interface
The human interface is an important tool for direct interaction and communication with the
human operator. It consists of integral means at the instrument for reading out data (local
display) and provisions for entering and requesting data (local pushbuttons). Instruments may
be provided that are not equipped with a huma
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