IEC 60770-2:2010

IEC 60770-2 ®
Edition 3.0 2010-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Transmitters for use in industrial-process control systems –
Part 2: Methods for inspection and routine testing

Transmetteurs utilisés dans les systèmes de conduite des processus
industriels –
Partie 2: Méthodes pour l'inspection et les essais individuels de série

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by
any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or
IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.
Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette
publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: inmail@iec.ch
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
§ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
§ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
§ Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
§ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: csc@iec.ch
Tel.: +41 22 919 02 11
Fax: +41 22 919 03 00
A propos de la CEI
La Commission Electrotechnique Internationale (CEI) est la première organisation mondiale qui élabore et publie des
normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications CEI
Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possédez
l’édition la plus récente, un corrigendum ou amendement peut avoir été publié.
§ Catalogue des publications de la CEI: www.iec.ch/searchpub/cur_fut-f.htm
Le Catalogue en-ligne de la CEI vous permet d’effectuer des recherches en utilisant différents critères (numéro de référence,
texte, comité d’études,…). Il donne aussi des informations sur les projets et les publications retirées ou remplacées.
§ Just Published CEI: www.iec.ch/online_news/justpub
Restez informé sur les nouvelles publications de la CEI. Just Published détaille deux fois par mois les nouvelles
publications parues. Disponible en-ligne et aussi par email.
§ Electropedia: www.electropedia.org
Le premier dictionnaire en ligne au monde de termes électroniques et électriques. Il contient plus de 20 000 termes et
définitions en anglais et en français, ainsi que les termes équivalents dans les langues additionnelles. Egalement appelé
Vocabulaire Electrotechnique International en ligne.
§ Service Clients: www.iec.ch/webstore/custserv/custserv_entry-f.htm
Si vous désirez nous donner des commentaires sur cette publication ou si vous avez des questions, visitez le FAQ du
Service clients ou contactez-nous:
Email: csc@iec.ch
Tél.: +41 22 919 02 11
Fax: +41 22 919 03 00
IEC 60770-2 ®
Edition 3.0 2010-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Transmitters for use in industrial-process control systems –
Part 2: Methods for inspection and routine testing

Transmetteurs utilisés dans les systèmes de conduite des processus
industriels –
Partie 2: Méthodes pour l'inspection et les essais individuels de série

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
N
CODE PRIX
ICS 25.040.40 ISBN 978-2-88912-223-3
– 2 – 60770-2 Ó IEC:2010
CONTENTS
FOREW ORD . 3
INTRODUCTION . 5
1 Scope and object . 6
2 Normativ e references . 6
3 Terms and definitions . 7
4 Sampling for test. 8
5 Performance tests . 8
5.1 General . 8
5.2 Test conditions . 8
5.2.1 Ambient conditions . 8
5.2.2 Supply conditions . 8
5.2.3 Load conditions . 9
5.3 Preconditioning . 9
5.4 Adjustments . 9
5.5 Tests under reference conditions . 9
5.5.1 Measured error and hysteresis . 9
5.5.2 Step response . 10
5.6 Effects of influence quantities . 11
5.6.1 Input signals and output load . 11
5.6.2 Power supply variations . 12
5.6.3 Ambient temperatures . 12
5.6.4 Ov er-range. 12
5.6.5 Static line pressure . 12
6 Test report and documentation . 13
Bibliography . 14

Figure 1 – Typical measured error plot . 10
Figure 2 – Two examples of responses to a step input . 11

Table 1 – Typical measured errors . 10

60770-2 Ó IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
___________
TRANSMITTERS FOR USE IN INDUSTRIAL-PROCESS
CONTROL SYSTEMS –
Part 2: Methods for inspection and routine testing

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.
International Standard IEC 60770-2 has been prepared by subcommittee 65B: Devices &
process analysis, of IEC technical committee 65: Industrial-process measurement, control
and automation.
This third edition cancels and replaces the second edition published in 2003. This edition
constitutes a technical revision.
The significant technical change with respect to the previous edition is as follows:
– The sequence in content has been reordered in Clause 5.
This standard should be read in conjunction with IEC 61298-1, IEC 61298-2, IEC 61298-3
and IEC 61298-4.
– 4 – 60770-2 Ó IEC:2010
The text of this standard is based on the following documents:
FDIS Report on voting
65B/760/FDIS 65B/773/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 IEC 60770 series, 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.
60770-2 Ó IEC:2010 – 5 –
INTRODUCTION
The methods of inspection and routine testing specified in this standard are intended for
use in acceptance tests or after repair to verify the fulfilment of the performance
specifications as established by the user. The methods given in this standard are primarily
intended for the testing of conventional analogue transmitters. For setting up test
procedures for microprocessor-based instruments IEC 60770-3 and IEC/TS 62098 should be
consulted.
– 6 – 60770-2 Ó IEC:2010
TRANSMITTERS FOR USE IN INDUSTRIAL-PROCESS
CONTROL SYSTEMS –
Part 2: Methods for inspection and routine testing

1 Scope and object
This part of IEC 60770 is applicable to transmitters, which have either a standard analogue
electric current output signal or a standard pneumatic output analogue signal in accordance
with IEC 60381-1 or IEC 60382. The tests detailed herein may be applied to transmitters
which have other output signals, provided that due allowance is made for such differences.
For the method of inspection and routine testing of the intelligent transmitters see
IEC 60770-3.
For certain types of transmitters, where the sensor is an integral part, other specific IEC or
ISO standards may need to be consulted (e.g. for chemical analyzers, flow-meters, etc.)
This standard is intended to provide technical methods for inspection and routine
testing of transmitters, for instance, for acceptance tests or after repair. For a full
evaluation, IEC 60770-1 and/or IEC 60770-3, respectively for analogue or intelligent
transmitters shall be used.
Quantitative criteria for acceptable performance should be established by agreement
between manufacturer and user.
By agreement the tests need not be carried out by an accredited laboratory.
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 – 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
IEC 60381-1:1982, Analogue signals for process control systems – Part 1: Direct current
signals
IEC 60382:1991, Analogue pneumatic signal for process control systems
IEC 60410:1973, Sampling plans and procedures for inspection by attributes
IEC 60770-1:1999, Transmitters for use in industrial-process control systems – Part 1:
Methods for performance evaluation

60770-2 Ó IEC:2010 – 7 –
IEC 60770-3:2006, Transmitters for use in industrial-process control systems – Part 3:
Methods for performance evaluation of intelligent transmitters
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 pro-
cedures for evaluation 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 61298-4:2008, Process measurement and control devices – General methods and
procedures for evaluating performance – Part 4: Evaluation report content
IEC/TS 62098:2000, Evaluation methods for microprocessor-based instruments
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
acceptance test
test proving to the user that the device complies with the performance specifications as
they appear in the contract
3.2
variable
quantity or condition whose value is subject to change and can usually be measured
EXAMPLE  temperature, flow rate, speed, signal, etc.
3.3
signal
physical variable of which one or more parameters carry information about one or more
variables represented by the signal
3.4
range
region of the values between the lower and upper limits of the quantity under consideration
3.5
span
algebraic difference between the upper and lower limit values of a given range
3.6
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
3.7
maximum measured error
largest positive or negative value of error of the upscale or downscale value of each point
of measurement
– 8 – 60770-2 Ó IEC:2010
3.8
hysteresis
greatest difference between the upscale and downscale output readings at one point
3.9
step response
time response of a transmitter produced by a stepwise variation of one of the input
variables
3.10
influence quantity
parameter chosen to represent one aspect of the environment under which a device may
operate
4 Sampling for test
If, by agreement between user and manufacturer, tests are to be performed only on
samples, it is recommended that a sampling method such as that presented in IEC 60410
be selected. When sampling is used, transmitters to be tested may be chosen by the user.
5 Performance tests
5.1 General
The tests listed in 5.5 and 5.6 shall be performed. Under certain circumstances, the user
may not require every test to be carried out. The sequence of the tests shall be such that
the results of a test are not affected by a previous test, provided proper pre-conditioning
has been performed.
5.2 Test conditions
5.2.1 Ambient conditions
– Temperature from 15 °C to 25 °C
– Relative humidity from 45 % to 75 %
– Atmospheric pressure from 86 kPa to 106 kPa
– Electromagnetic field value to be stated if relevant
The maximum rate of change of ambient temperature permissible during any test shall be
1 °C in 10 min, but not more than 3 °C per hour.
5.2.2 Supply conditions
Electrical supply:
– rated voltage ±1 %
– rated frequency ±1 %
– harmonic distortion (a.c. supply) less than 5 %
– ripple (d.c. supply) less than 0,1 %
Pneumatic supply:
– rated pressure ±3 %
– supply air temperature ambient temperature ±2 °C

60770-2 Ó IEC:2010 – 9 –
– supply air humidity dew-point at least 10 °C below device body
temperature
-6
– oil and dust content oil: less than 1 ´ 10 by weight
dust: absence of particles greater than 3 mm
5.2.3 Load conditions
Electrical instrumentation:
– voltage output signals: the minimum load value specified by the manufacturer
– current output signals: the maximum load value specified by the manufacturer
Pneumatic instrumentation:
– a rigid tube 8 m long and 4 mm internal diameter connected to a 20 cm rigid container.
5.3 Preconditioning
For preconditioning with power applied to the transmitter, sufficient time (not less than 30
min) should be allowed to ensure stabilization of the operating temperature of the
transmitter.
5.4 Adjustments
The routine tests shall be carried out (as an acceptance test or after repair) with the
adjustments for lower range value, span and damping determined by the user in
consultation with the manufacturer.
5.5 Tests under reference conditions
5.5.1 Measured error and hysteresis
The input-output characteristic under reference conditions shall be measured in one
measurement cycle, traversing the full range in each direction. For this, at least five points
of measurement should be evenly distributed over the range; they should include points at
or near (within 10 % of span) the 0 % and 100 % values of the span.
NOTE For instruments with a non-linear input-output relationship (e.g. square law), the test points should be
chosen so as to obtain output values equally distributed over the output span.
Measurement procedure:
Initially, an input signal equal to the lower range value is generated and the value of the
corresponding input and output signal is noted. Then the input signal is slowly increased to
reach, without overshoot, the first test point. After an adequate stabilization period, the
value of the corresponding input and output signal is noted.
The operation is repeated for all the predetermined values up to 100 % of the input span.
After measurement at this point, the input signal is slowly brought down, without overshoot,
to the test value directly below 100 % of input span, and then to all other values in turn
down to 0 % of input span, thus closing the measurement cycle.
The difference between the output signal values obtained at the test points for each upscale
and downscale traverse and the corresponding ideal values are recorded as the measured
errors. The errors generally shall be expressed as percent of the ideal output span. All the
error values thus obtained shall be shown in a tabular form (see Table 1) and presented
graphically (see Figure 1).
– 10 – 60770-2 Ó IEC:2010
Table 1 – Typical measured errors
Output (% of span) 0 20 40 60 80 100
Measured error up  0,09 −0,04 −0,23 −0,22 0,10
Measured error down −0,06 0,26 0,17 −0,08 −0,13
Maximum measured error −0,06 0,26 0,17 −0,23 −0,22 0,10
Hysteresis 0,17 0,21 0,15 0,09

From Table 1, the maximum measured error found is 0,26 % and the maximum hysteresis is
0,21 %. The data from Table 1 are plotted in Figure 1.

0,3
0,2
Maximum
measured error
0,1
Maximum
hysteresis
0 10 20 30 40 50 60 70 80 90 100
–0,1
–0,2
–0,3
Output (% span)
IEC  2363/10
Figure 1 – Typical measured error plot
5.5.2 Step response
Output loading:
Electrical transmitters: Values specified by the manufacturer or a 0,1 mF capacitor in
parallel with the reference load resistance.
Pneumatic transmitters: An 8 m length of 4 mm internal diameter rigid pipe connected to a
20 cm rigid container.
Measurement procedure:
Two steps corresponding to 80 % of output span, preferably from 10 % to 90 %, then from
90 % to 10 % shall be applied.
The settling time, the time for the output to reach and remain within 1 % of the span of its
steady state value shall be reported for each step. The amount of dead time, rise time, time
constant and overshoot (in percentage of span), if any, shall also be reported. Figure 2
illustrates the definitions of the times and gives examples of responses to a positive step
input.
NOTE If there is difficulty in generating or recording an accurate input step, due to the physical characteristics or
range of the input variable, the dynamics required for this test should be agreed between the manufacturer and
the user. Where there is no concern about the step response, this test may be omitted.

Deviation, % output span
60770-2 Ó IEC:2010 – 11 –
Input signal
Input step to produce required
output response
Transient
overshoot
Output
response Final steady Specified band ± 1 % of span
output
100 %
90 %
Dead
time
10 %
Rise time
Step response time
Time
Settling time
Output
response
Final steady - 1 %
state value
100 %
63 %
Dead
time
Time constant
Time
Settling time
IEC  2364/10
Figure 2 – Two examples of responses to a step input
5.6 Effects of influence quantities
5.6.1 Input signals and output load
Input signals: the tests described in 5.6.2, 5.6.3, 5.6.4 and 5.6.5 shall each be conducted
with input signals of 0 % and 100 % of span if the transmitter output is able to go at least
2 % below its lower range value and at least 2 % above its upper range value. Otherwise,
suitable input signals such as 5 % and 95 % of span shall be substituted.
Output load: electrical transmitters should be connected to maximum rated output load (for
current output).
– 12 – 60770-2 Ó IEC:2010
5.6.2 Power supply variations
Using each chosen input signal, the user shall measure and report the change of output in
percentages of span at the following variations in power supply or at the manufacturer’s
stated limits, whichever is smaller:
Voltage variation: +10 % to –15 % of nominal a.c. voltage and +20 % to –15 % for nominal
d.c. voltage (IEC 61298-3) (for 2-wire transmitters the load has also to be taken in account).
Pneumatic supply pressure variation: +10 % to –15 % of nominal pressure (IEC 61298-3).
5.6.3 Ambient temperatures
The user shall measure and report at 0 % and 100 % input signal the change in observed
output signal. This shall be carried out at each of the following ambient temperatures:
a) 20 °C (reference);
b) maximum operating temperature specified by the manufacturer;
c) 20 °C;
d) minimum operating temperature specified by the manufacturer;
e) 20 °C;
The tolerance for each test temperature should be ±2 °C and the rate of change of ambient
temperature should be less than 1 °C per minute.
Before measuring the influence effect, sufficient time (usually 3 h) shall be allowed for
stabilization of the temperature of all parts of the transmitter.
Output changes shall be reported as percentages of output span.
NOTE This test may be omitted only where there is no concern about ambient temperature effects.
5.6.4 Over-range
Before this test, measurements of the output shall be performed at 0 % and 100 % input
values. The input shall then be increased to the maximum over-range value specified by the
manufacturer. After the over-range value has been applied for 1 min, the input shall be
reduced to the nominal lower range value. After a further 5 min have elapsed, using the
same input levels as before, determine the changes in observed output values.
Differential pressure transmitters are to be tested for over-range effects in both directions.
They shall be tested as described above, first over-ranging the positive chamber and then
over-ranging the negative chamber. The changes in output, determined after over-ranging
in each direction, shall be reported.
Output changes shall be reported as percentages of output span.
5.6.5 Static line pressure
This test shall be carried out on transmitters which in normal operation are subjected to line
pressure.
Before this test, measurements of the output shall be performed at 0 % and 100 % input
values. The pressure shall be changed from atmospheric to the full working pressure of the
instrument. For some applications, this test may also be required to be performed at
pressures below atmospheric pressure. Using the same input levels as before, the changes
in observed output values shall be measured.

60770-2 Ó IEC:2010 – 13 –
NOTE Measuring the static pressure influence with inputs other than zero differential pressure is very difficult to
realise for differential pressure transmitters. If this should be required, a separate agreement between manufacturer
and user is recommended.
Output changes shall be reported as percentages of output span.
6 Test report and documentation
A complete test report of the evaluation shall be prepared after the completion of the tests.
The test report shall have the following generic lay-out:
· Title page with
– abridged name and type/model number of the instrument;
– name of the manufacturer;
– name and address of the laboratory;
– names and signatures of evaluator and his next principal (report authorizer);
– identification code of the report and date of issue.
· Introduction with
– aim of the tests;
– name and address of the manufacturer;
– model, type, serial number and date of manufacture (or final assembly) of the
instrument;
– short description of the instrument, type and number of sensors, measuring range,
recording method, measurement intervals, memory size in terms of number of
messages, supply and energy consumption;
– period and year in which tests are performed;
– test methods used and test methods omitted or varied.
· Conclusions and test results with
– summary with conclusions with respect to the applicability based on the test results
and other qualitative findings;
– table in which all test results are conveniently arranged.
All the original documentation related to the measurements made during the tests s
...