SIST EN 61298-2:2009

Process measurement and control devices - General methods and procedures for evaluating performance -- Part 2: Tests under reference conditions

This part of IEC 61298 specifies general methods and procedures for conducting tests and reporting on the functional and performance characteristics of process measurement and control devices. The tests are applicable to any such devices characterized by their own specific input and output variables, and by the specific relationship (transfer function) between the inputs and outputs, and include analogue and digital devices. For devices that require special tests, this standard should be used, together with any product specific standard specifying special tests. This standard covers tests made under reference conditions.

Prozessmess-, -steuer- und -regelgeräte – Allgemeine Methoden und Verfahren für die Bewertung des Betriebsverhaltens – Teil 2: Prüfungen unter Referenzbedingunge

Dispositifs de mesure et de commande de processus - Méthodes et procédures générales d'évaluation des performances -- Partie 2: Essais dans les conditions de référence

La CEI 61298-2:2008 spécifie les méthodes et procédures générales pour l'exécution des essais portant sur les caractéristiques fonctionnelles et les caractéristiques de performance des dispositifs de mesure et de commande de processus. Ces essais sont applicables à tout dispositif à condition que ce dispositif soit caractérisé par ses propres grandeurs d'entrée et de sortie et par la relation spécifique (fonction de transfert) entre les entrées et les sorties. Ils concernent les dispositifs analogiques et numériques. Pour les dispositifs nécessitant des essais spéciaux, il convient que cette norme soit utilisée en conjonction avec la norme particulière de produit spécifiant ces essais spéciaux. Elle couvre les essais effectués dans les conditions de référence.

Naprave za merjenje in nadzor procesa - Splošne metode in postopki za ocenjevanje lastnosti - 2. del: Preskusi pri referenčnih pogojih (IEC 61298-2:2008)

General Information

• Status: Published
• Publication Date: 02-Mar-2009
• ICS: 25.040.40 - Industrial process measurement and control
• Technical Committee: MOV - Measuring equipment for electromagnetic quantities
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 11-Feb-2009
• Due Date: 18-Apr-2009
• Completion Date: 03-Mar-2009
• Ref Project: EN 61298-2:2008 - Process measurement and control devices - General methods and procedures for evaluating performance - Part 2: Tests under reference conditions

Relations

• Replaces: SIST EN 61298-2:1998 - Process measurement and control devices - General methods and procedures for evaluating performance -- Part 2: Tests under reference conditions
• Effective Date: 01-Nov-2011
• Replaces: SIST EN 61298-2:1998 - Process measurement and control devices - General methods and procedures for evaluating performance -- Part 2: Tests under reference conditions
• Effective Date: 29-Jan-2023
• Replaces: SIST EN 61298-2:1998 - Process measurement and control devices - General methods and procedures for evaluating performance -- Part 2: Tests under reference conditions
• Effective Date: 13-May-2010
• Replaces: SIST EN 61298-2:1998 - Process measurement and control devices - General methods and procedures for evaluating performance -- Part 2: Tests under reference conditions
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 61298-2:2009
01-april-2009
1DGRPHãþD
SIST EN 61298-2:1998
1DSUDYH]DPHUMHQMHLQQDG]RUSURFHVD6SORãQHPHWRGHLQSRVWRSNL]D
RFHQMHYDQMHODVWQRVWLGHO3UHVNXVLSULUHIHUHQþQLKSRJRMLK,(&
Process measurement and control devices - General methods and procedures for
evaluating performance -- Part 2: Tests under reference conditions
Prozessmess-, -steuer- und -regelgeräte – Allgemeine Methoden und Verfahren für die
Bewertung des Betriebsverhaltens – Teil 2: Prüfungen unter Referenzbedingunge
Dispositifs de mesure et de commande de processus - Méthodes et procédures
générales d'évaluation des performances -- Partie 2: Essais dans les conditions de
référence
Ta slovenski standard je istoveten z: EN 61298-2:2008
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
SIST EN 61298-2:2009 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 61298-2:2009

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SIST EN 61298-2:2009

EUROPEAN STANDARD
EN 61298-2

NORME EUROPÉENNE
November 2008
EUROPÄISCHE NORM

ICS 25.040.40 Supersedes EN 61298-2:1995


English version


Process measurement and control devices -
General methods and procedures for evaluating performance -
Part 2: Tests under reference conditions
(IEC 61298-2:2008)


Dispositifs de mesure  Prozessmess-, -steuer- und -regelgeräte -
et de commande de processus - Allgemeine Methoden und Verfahren für
Méthodes et procédures générales die Bewertung des Betriebsverhaltens -
d'évaluation des performances - Teil 2: Prüfungen
Partie 2: Essais dans les conditions unter Referenzbedingungen
de référence (IEC 61298-2:2008)
(CEI 61298-2:2008)




This European Standard was approved by CENELEC on 2008-11-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: rue de Stassart 35, B - 1050 Brussels


© 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61298-2:2008 E

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SIST EN 61298-2:2009
EN 61298-2:2008 - 2 -
Foreword
The text of document 65B/686/FDIS, future edition 2 of IEC 61298-2, prepared by SC 65B, Devices &
process analysis, of IEC TC 65, Industrial-process measurement, control and automation, was submitted
to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61298-2 on 2008-11-01.
This European Standard supersedes EN 61298-2:1995.
EN 61298-2:2008 is a general revision with respect to EN 61298-2:1995 and does not include any
significant changes (see Introduction).
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2009-08-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2011-11-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 61298-2:2008 was approved by CENELEC as a European
Standard without any modification.
__________

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SIST EN 61298-2:2009
- 3 - EN 61298-2:2008
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.

Publication Year Title EN/HD Year

1)
IEC 60050-300 - International Electrotechnical Vocabulary - -
(IEV) - Electrical and electronic
measurements and measuring instruments -
Part 311: General terms relating to
measurements -
Part 312: General terms relating to electrical
measurements -
Part 313: Types of electrical measuring
instruments -
Part 314: Specific terms according to the type
of instrument


1)
IEC 60050-351 - International Electrotechnical Vocabulary - -
(IEV) -
Part 351: Control technology


1) 2)
IEC 61010-1 - Safety requirements for electrical equipment EN 61010-1 2001
for measurement, control, and laboratory + corr. June 2002
use -
Part 1: General requirements


1) 2)
IEC 61298-1 - Process measurement and control devices - EN 61298-1 2008
General methods and procedures for
evaluating performance -
Part 1: General considerations





1)
Undated reference.
2)
Valid edition at date of issue.

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SIST EN 61298-2:2009

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SIST EN 61298-2:2009
IEC 61298-2
Edition 2.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Process measurement and control devices – General methods and procedures
for evaluating performance –
Part 2: Tests under reference conditions

Dispositifs de mesure et de commande de processus – Méthodes et procédures
générales d'évaluation des performances –
Partie 2: Essais dans les conditions de référence

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
U
CODE PRIX
ICS 25.040.40 ISBN 2-8318-1003-1
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN 61298-2:2009
– 2 – 61298-2 © IEC:2008
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .7
4 Accuracy related factors .10
4.1 Test procedures and precautions .10
4.1.1 Selection of ranges for test.10
4.1.2 Preconditioning cycles.11
4.1.3 Number of measurement cycles and test points .11
4.1.4 Additional tests where digital inputs and outputs are provided .11
4.1.5 Measurement procedure .11
4.1.6 Processing of the measured values .12
4.1.7 Determination of accuracy related factors.12
4.1.8 Presentation of the results.16
4.2 Specific testing procedures and precautions for the determination of dead
band.16
4.2.1 Selection of ranges for test and preconditioning .16
4.2.2 Measurement procedure .16
4.2.3 Presentation of the results.17
5 Dynamic behaviour.17
5.1 General considerations.17
5.2 General testing procedures and precautions.17
5.3 Frequency response.17
5.4 Step response .18
6 Functional characteristic.18
6.1 General .18
6.2 Input resistance of an electrical device.18
6.3 Insulation of electrical devices.21
6.3.1 General considerations.21
6.3.2 Insulation resistance.21
6.3.3 Dielectric strength .22
6.4 Power consumption .22
6.4.1 Electrical power consumption .22
6.4.2 Air consumption.22
6.5 Output ripple of a device with an electrical d.c. output .23
6.6 Air flow characteristics of a pneumatic device .23
6.6.1 Initial setting up .23
6.6.2 Delivered flow Q .23
1
6.6.3 Exhausted flow Q .24
2
6.6.4 Data presentation .24
6.7 Limits of adjustments of lower range value and span.25
6.8 Switching differential .25
7 Drift .25
7.1 Start-up drift .25
7.2 Long-term drift.25

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SIST EN 61298-2:2009
61298-2 © IEC:2008 – 3 –

Figure 1 – Error curves .15
Figure 2 – Two examples of frequency response .19
Figure 3 – Two examples of responses to a step input.20
Figure 4 – Test set-up for input resistance .21
Figure 5 – Test arrangement for measurement of airflow characteristics .23
Figure 6 – Typical air flow characteristics .24

Table 1 – Settings of span and lower range value adjustments .11
Table 2 – Number of measurement cycles and number and location of test points .12
Table 3 – Typical table of device errors .14
Table 4 – Dielectric strength test voltages .22

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SIST EN 61298-2:2009
– 4 – 61298-2 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

PROCESS MEASUREMENT AND CONTROL DEVICES –
GENERAL METHODS AND PROCEDURES
FOR EVALUATING PERFORMANCE –

Part 2: Tests under reference conditions


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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 61298-2 has been prepared by subcommittee 65B: Devices and
process analysis, of IEC technical committee 65: Industrial-process measurement, control and
automation.
This second edition cancels and replaces the first edition published in 1995 and constitutes a
technical revision.
This edition is a general revision with respect to the previous edition and does not include any
significant changes (see Introduction).

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SIST EN 61298-2:2009
61298-2 © IEC:2008 – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
65B/686/FDIS 65B/694/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 of the IEC 61298 series, under the general title Process measurement and
control devices – General methods and procedures for evaluating performance, can be found
on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.

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SIST EN 61298-2:2009
– 6 – 61298-2 © IEC:2008
INTRODUCTION
This standard is not intended as a substitute for existing standards, but is rather intended as a
reference document for any future standards developed within the IEC or other standards
organizations, concerning the evaluation of process instrumentation. Any revision of existing
standards should take this standard into account.
This common standardized basis should be utilised for the preparation of future relevant
standards, as follows:
– any test method or procedure, already treated in this standard, should be specified and
described in the new standard by referring to the corresponding clause of this standard.
Consequently new editions of this standard are revised without any change in numbering
and scope of each clause;
– any particular method or procedure, not covered by this standard, should be developed
and specified in the new standard in accordance with the criteria, as far as they are
applicable, stated in this standard;
– any conceptual or significant deviation from the content of this standard, should be clearly
identified and justified if introduced in a new standard.

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SIST EN 61298-2:2009
61298-2 © IEC:2008 – 7 –
PROCESS MEASUREMENT AND CONTROL DEVICES –
GENERAL METHODS AND PROCEDURES
FOR EVALUATING PERFORMANCE –

Part 2: Tests under reference conditions



1 Scope
This part of IEC 61298 specifies general methods and procedures for conducting tests and
reporting on the functional and performance characteristics of process measurement and
control devices. The tests are applicable to any such devices characterized by their own
specific input and output variables, and by the specific relationship (transfer function) between
the inputs and outputs, and include analogue and digital devices. For devices that require
special tests, this standard should be used, together with any product specific standard
specifying special tests.
This standard covers tests made under reference conditions.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60050-300, International Electrotechnical Vocabulary (IEV) – Electrical and electronic
measurements and measuring instruments (composed of Part 311, 312, 313 and 314)
IEC 60050-351, International Electrotechnical Vocabulary (IEV) – Part 351 : Control
technology
IEC 61298-1, Process measurement and control devices – General methods and procedures
for evaluating performance – Part 1: General considerations
IEC 61010-1, Safety requirements for electrical equipment for measurement, control, and
laboratory use – Part 1: General requirements
3 Terms and definitions
For the purpose of this document, the following relevant terms and definitions, some of them
based on IEC 60050(300) or IEC 60050(351), apply.
3.1
variable
quantity or condition whose value is subject to change and can usually be measured (e.g.,
temperature, flow rate, speed, signal, etc.)
[IEV 351-21-01, modified]
3.2
signal
physical quantity, one or more parameters of which carry information about one or more
variables which the signal represents
[IEV 351-21-51, modified]

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SIST EN 61298-2:2009
– 8 – 61298-2 © IEC:2008
3.3
range
range of values defined by the two extreme values within which a variable can be measured
within the specified accuracy
[IEV 351-27-11, modified]
3.4
span
algebraic difference between the values of the upper and lower limits of the measuring range
[IEV 311-03-13]
3.5
inaccuracy
maximum positive and negative deviation from the specified characteristic curve observed in
testing a device under specified conditions and by a specified procedure
NOTE 1 Accuracy is defined in IEC 60050-300, definition 311-06-08.
NOTE 2 The term inaccuracy is sometime referred to as measured accuracy. This term should not be used.
3.6
error
algebraic difference between the indicated value and a comparison value of the measured
variable
[IEV 351-27-04, modified]
NOTE The error is positive when the indicated value is greater than the comparison value. The error is generally
expressed as a percentage of the relevant ideal span.
3.7
measured error
largest positive or negative value of errors of the average upscale or downscale values at
each point of measurement
3.8
non-conformity
the closeness with which a calibration curve approximates to a specified characteristic curve
(which can be linear, logarithmic, parabolic, etc.)
NOTE Non-conformity does not include hysteresis.
3.9
non-linearity
deviation from linearity
NOTE 1 Linearity is defined in IEC 60050(300), definition 311-06-05.
NOTE 2 Non-linearity does not include hysteresis.
3.10
non-repeatability
deviation from repeatability
NOTE Repeatability is defined in IEC 60050(300), definition 311-06-06.
3.11
hysteresis
property of a device or instrument whereby it gives different output values in relation to its
input values depending on the directional sequence in which the input values have been
applied
[IEV 351-24-15, modified]

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SIST EN 61298-2:2009
61298-2 © IEC:2008 – 9 –
3.12
dead band
finite range of values within which a variation of the input variable does not produce any
measurable change in the output variable
[IEV 351-24-14, modified]
3.13
dead-time
time interval between the instant when a variation of an input variable is produced, and the
instant when the subsequent variation of the output variable starts
[IEV 351-28-41]
(see IEC 60050-351, Figure 5)
3.14
rise time
for a step response, the duration of the time interval between the instant when the output
variable (starting from zero) reaches a small specified percentage (for instance 10 %) of the
final steady-state value, and the instant when it reaches for the first time a large specified
percentage (for instance 90 %) of the same difference
[IEV 394-39-11, modified]
(see IEC 60050-351, Figure 3)
3.15
settling time
time interval between the instant of the step change of an input variable, and the instant when
the output variable does not deviate by more than a specified tolerance from its final steady
state value (see IEC 60050-351, Figure 3). For this standard, a tolerance of 1 % is adopted
[IEV 351-24-29]
3.16
step response time
time interval between the instant of a step change in the input variable and the instant when
the output variable reaches for the first time a specified percentage of the difference between
the final and the initial steady state value (see IEC 60050-351, Figure 3). For this standard , a
specified percentage of 90 % is adopted
[IEV 351-24-28]
3.17
time constant
time required to complete 63,2 % of the total change of the output of a first-order linear
system, produced by a step variation of the input variable
[IEV 351-24-24]
3.18
test procedure
statement of the tests to be carried out, and the conditions for each test, agreed between the
manufacturer, the test laboratory, and the purchaser/user before the evaluation starts
3.19
type tests
a test of one or more devices made to a certain design to show that the design meets certain
specifications
NOTE The type tests are in principle applied only on a sample. Normally are not repeated on all the individual
units of equipment made in series.

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SIST EN 61298-2:2009
– 10 – 61298-2 © IEC:2008
3.20
performance evaluation
a complete test to establish the performance of a device under any likely operating conditions
to permit comparison with the manufacturer’s published or stated performance specification
for the device, or the user’s requirements
3.21
routine test
a simplified test to which each individual instrument is subjected during or after manufacture
to ascertain whether it complies with certain criteria
3.22
sample test
a simplified test to check specific characteristics of a device
4 Accuracy related factors
4.1 Test procedures and precautions
4.1.1 Selection of ranges for test
Where there are switched ranges or dial settings (e.g., gain), the tests shall be repeated to
cover all ranges or settings. When the Device Under Test (DUT) is supplied calibrated for use,
the first set of tests shall be carried out without adjustment.
4.1.1.1 Criteria
The measurements shall be performed with the devices operating at the minimum number of
calibration settings necessary to establish the device performance in all required operational
settings required by the test programme (see Clause 5 of IEC 61298-1).
Testing of a device which has provision for substantial adjustment of both span and lower
range value may require an impractically large number of tests. In such a case, preliminary
tests shall be conducted to determine the effect of changing span and lower range value
adjustments on the characteristic being measured. This should enable some tests to be
eliminated from the test programme in cases where the characteristic can be inferred reliably
from fewer tests. For example, hysteresis may not be significantly affected by selection of the
lower and upper range value if the span is held constant, and often may be inferred for
different spans from measurements at a single span setting.
However, the report shall indicate clearly relevant values of the measured parameters for
each setting of the adjustments, so that the values of inaccuracy, hysteresis, etc, can all be
referenced to the same adjustment of the device.
4.1.1.2 Setting of span and lower range value adjustments
Generally, unless otherwise specified in the test programme, the test for accuracy related
factors shall be carried out with the adjustments set at the settings A, B, C, D, listed below,
and in accordance with Table 1 whenever the span and/or the lower range value adjustments
are adjustable further than the adjustments for the manufacturing tolerances.
NOTE For tests of dynamic behaviour, functional characteristics, and drift, refer to the appropriate clauses of this
standard.

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SIST EN 61298-2:2009
61298-2 © IEC:2008 – 11 –
Table 1 – Settings of span and lower range value adjustments
Zero suppression
Kind of test Adjustable span
and/or elevation
Complete Performance evaluation
A B
Tests Type test
Simplified Routine tests
C D
Tests Sample test

Setting A – Span adjustment set at the maximum and minimum values specified by the
manufacturer, and at one intermediate value.
Setting B – Normally, tests will be done at only one setting of lower range value, without
suppression or elevation, but further tests at minimum and maximum settings
may be required if the effects are significant.
Setting C – Unless otherwise specified in the test programme, the span shall be as set by
the manufacturer.
Setting D – Unless otherwise specified in the test programme, the lower range
...