Guide to specification of hydraulic turbine governing systems

This International Standard includes relevant technical data necessary to describe hydraulic turbine governing systems and to define their performance. It is aimed at unifying and thus facilitating the selection of relevant parameters in bidding specifications and technical bids. It will also serve as a basis for setting up technical guarantees. The scope of this standard is restricted to the turbine governing level. Additionally some remarks about the control loops of the plant level and about primary and secondary frequency control (see also Annex B) are made for better understanding without making a claim to be complete. Important topics covered by the guide are: - speed, power, water level, opening and flow (discharge) control for reaction and impulsetype turbines including double regulated machines; - means of providing actuating energy; - safety devices for emergency shutdown, etc. To facilitate the setting up of specifications, this guide also includes data sheets, which are to be filled out by the customer and the supplier in the various stages of the project and the contract. Acceptance tests, specific test procedures and guarantees are outside the scope of the guide; those topics are covered by IEC 60308.

Leitfaden zur Spezifikation der Regeleinrichtung von Wasserturbinen

Guide pour la spécification des systèmes de régulation des turbines hydrauliques

La CEI 61362:2012 contient les données techniques nécessaires pour décrire les systèmes de régulation des turbines hydrauliques et définir leurs performances. Elle a pour but d'unifier et ainsi de faciliter les spécifications des appels d'offres et les offres techniques. Elle servira également de base pour fixer les garanties techniques. Le domaine d'application de la présente norme est limité au niveau du régulateur turbine. En outre, des remarques sur les boucles de contrôle au niveau de la centrale ainsi que sur le réglage de fréquence primaire et secondaire (voir aussi l'Annexe B) apportent une meilleure compréhension sans avoir la prétention d'être exhaustives. Le guide traite les fonctions importantes suivantes: - les régulations de vitesse, puissance, niveau d'eau, ouverture et débit (décharge) des turbines à réaction et des turbines à action, y compris les machines à double régulation; - les moyens de production de l'énergie de manoeuvre; - les dispositifs de sécurité pour l'arrêt d'urgence, etc. Pour faciliter la rédaction des spécifications, ce guide inclut des formulaires de données à remplir par le client et par le fournisseur aux différentes étapes du projet et du contrat. Les essais de réception, les procédures d´essais spécifiques et les garanties ne sont pas traités par le guide mais par la CEI 60308. Cette deuxième édition annule et remplace la première édition parue en 1998. Elle constitue une révision technique qui tient compte de l'expérience acquise avec le guide au cours des dix dernières années ainsi que du progrès des technologies sous-jacentes. Mots clé: turbines hydrauliques, systèmes de régulation des turbines hydrauliques.

Vodilo za specificiranje sistemov za krmiljenje hidravličnih turbin

Ta mednarodni standard vključuje zadevne tehnične podatke, potrebne za opis sistemov za krmiljenje hidravličnih turbin in določitev njihove zmogljivosti. Njegov namen je združiti in s tem poenostaviti izbor ustreznih parametrov pri razpisnih specifikacijah in tehničnih ponudbah. Prav tako bo služil kot osnova za ureditev tehničnih jamstev. Področje uporabe tega standarda je omejeno na raven krmiljenja turbin. Poleg tega so za boljše razumevanje navedene nekatere opombe glede krmilnih zank na ravni naprave ter primarne in sekundarne kontrole frekvence (glej tudi dodatek B), vendar niso popolne. Pomembne teme, vključene v navodilih, so: – hitrost, moč, nivo vode, kontrola odpiranja in pretoka (iztoka) za reakcijske in impulzne turbine, vključno z dvojno uravnavanimi stroji; – načini zagotavljanja pogonske energije; – varnostne naprave za izklop v sili itd. Za lažjo določitev specifikacij vključujejo ta navodila tudi obrazce, ki jih stranka in dobavitelj izpolnjujeta v različnih fazah projekta in pogodbe. Testi sprejemljivosti, posebni preskusni postopki in jamstva ne spadajo na področje uporabe navodil; ta vprašanja zajema standard IEC 60308.

General Information

Status
Published
Publication Date
23-Sep-2012
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
06-Sep-2012
Due Date
11-Nov-2012
Completion Date
24-Sep-2012

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SLOVENSKI STANDARD
SIST EN 61362:2012
01-oktober-2012
9RGLOR]DVSHFLILFLUDQMHVLVWHPRY]DNUPLOMHQMHKLGUDYOLþQLKWXUELQ
Guide to specification of hydraulic turbine governing systems
Leitfaden zur Spezifikation der Regeleinrichtung von Wasserturbinen
Guide pour la spécification des systèmes de régulation des turbines hydrauliques
Ta slovenski standard je istoveten z: EN 61362:2012
ICS:
27.140 Vodna energija Hydraulic energy engineering
SIST EN 61362:2012 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 61362:2012
---------------------- Page: 2 ----------------------
SIST EN 61362:2012
EUROPEAN STANDARD
EN 61362
NORME EUROPÉENNE
August 2012
EUROPÄISCHE NORM
ICS 27.140 Supersedes EN 61362:1998
English version
Guide to specification of hydraulic turbine governing systems
(IEC 61362:2012)
Guide pour la spécification des systèmes Leitfaden zur Spezifikation der
de régulation des turbines hydrauliques Regeleinrichtung von Wasserturbinen
(CEI 61362:2012) (IEC 61362:2012)

This European Standard was approved by CENELEC on 2012-05-25. 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.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 61362:2012 E
---------------------- Page: 3 ----------------------
SIST EN 61362:2012
EN 61362:2012 - 2 -
Foreword

The text of document 4/270/FDIS, future edition 2 of IEC 61362, prepared by IEC/TC 4 "Hydraulic

turbines" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as

EN 61362:2012.
The following dates are fixed:
(dop) 2013-02-28
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2015-05-25
• latest date by which the national
standards conflicting with the
document have to be withdrawn
This document supersedes EN 61362:1998.

EN 61362:2012 includes the following significant technical changes with respect to EN 61362:1998:

This technical revision takes into account the experience with the guide during the last decade as well

as the progress in the state of the art of the underlying technologies.

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 61362:2012 was approved by CENELEC as a European

Standard without any modification.
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SIST EN 61362:2012
- 3 - EN 61362:2012
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 When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD

applies.
Publication Year Title EN/HD Year
IEC 60050-351 2006 International Electrotechnical Vocabulary - -
(IEV) -
Part 351: Control technology
IEC 60068-2-6 2007 Environmental testing - EN 60068-2-6 2008
Part 2-6: Tests - Test Fc: Vibration
(sinusoidal)
IEC 60068-2-27 2008 Environmental testing - EN 60068-2-27 2009
Part 2-27: Tests - Test Ea and guidance:
Shock
IEC 60308 2005 Hydraulic turbines - Testing of control EN 60308 2005
systems
IEC 61000-4-1 2006 Electromagnetic compatibility (EMC) - EN 61000-4-1 2007
Part 4-1: Testing and measurement
techniques - Overview of IEC 61000-4 series
CISPR 11 2009 Industrial, scientific and medical equipment - EN 55011 2009
(mod) Radio-frequency disturbance characteristics
- Limits and methods of measurement
ISO 3448 1992 Industrial liquid lubricants - ISO viscosity - -
classification
---------------------- Page: 5 ----------------------
SIST EN 61362:2012
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SIST EN 61362:2012
IEC 61362
Edition 2.0 2012-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Guide to specification of hydraulic turbine governing systems
Guide pour la spécification des systèmes de régulation des turbines
hydrauliques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX
ICS 27.140 ISBN 978-2-8322-0057-5

Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN 61362:2012
– 2 – 61362 © IEC:2012
CONTENTS

FOREWORD ........................................................................................................................... 5

INTRODUCTION ..................................................................................................................... 7

1 Scope ............................................................................................................................... 8

2 Normative references........................................................................................................ 8

3 Terms, definitions, symbols and units ................................................................................ 9

3.1 General terms and definitions .................................................................................. 9

3.2 Terms and definitions related to control levels and control modes ............................ 9

3.3 Terms and definitions from control theory ................................................................ 9

3.4 Subscripts and prefixes ......................................................................................... 10

3.5 Terms and definitions related to the plant and the machines ................................... 10

3.6 Terms and definitions relating to the governing system .......................................... 11

4 Control structure ............................................................................................................. 18

4.1 General ................................................................................................................. 18

4.2 Main control functions ............................................................................................ 18

4.2.1 General ..................................................................................................... 18

4.2.2 Speed control ............................................................................................ 19

4.2.3 Power output control .................................................................................. 19

4.2.4 Opening control ......................................................................................... 19

4.2.5 Water level control ..................................................................................... 19

4.2.6 Flow control ............................................................................................... 20

4.3 Configurations of combined control systems .......................................................... 20

4.3.1 General ..................................................................................................... 20

4.3.2 Parallel structure........................................................................................ 20

4.3.3 Series structures ........................................................................................ 21

4.3.4 Other configurations .................................................................................. 22

4.4 Configurations of servo-positioners ........................................................................ 23

4.5 Multiple control ...................................................................................................... 23

4.5.1 General ..................................................................................................... 23

4.5.2 Parallel structure........................................................................................ 24

4.5.3 Series structure ......................................................................................... 24

5 Performance and components of governing systems ....................................................... 24

5.1 General ................................................................................................................. 24

5.2 Modeling and digital simulation .............................................................................. 25

5.3 Characteristic parameters for PID-controllers ......................................................... 26

5.3.1 General ..................................................................................................... 26

5.3.2 Permanent droop b ................................................................................... 27

5.3.3 Proportional action coefficient K , integral action time T , and
p I

derivative action time T ............................................................................ 27

5.4 Other parameters of the governing systems ........................................................... 28

5.4.1 Command signal adjustments for controlled variables (speed, power

output, etc.) and load limiter ....................................................................... 28

5.4.2 Governor insensitivity i /2 ........................................................................... 28

5.4.3 Parameters of servo-positioner .................................................................. 29

5.5 Functional relationship between servo-positioners .................................................. 30

5.5.1 Dual regulation of turbines with controllable guide vane and runner

blade angles .............................................................................................. 30

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SIST EN 61362:2012
61362 © IEC:2012 – 3 –

5.5.2 Dual control of turbines with needles and deflectors ................................... 31

5.5.3 Multiple control .......................................................................................... 31

5.5.4 Other relationships ..................................................................................... 31

5.6 Actual signal measurement .................................................................................... 31

5.6.1 General ..................................................................................................... 31

5.6.2 Rotational speed ........................................................................................ 32

5.6.3 Power output ............................................................................................. 32

5.6.4 Water level ................................................................................................ 32

5.6.5 Actuator position (stroke) ........................................................................... 32

5.6.6 Signal transmission from electronic transmitters ......................................... 32

5.7 Manual control ....................................................................................................... 33

5.8 Linearization .......................................................................................................... 33

5.9 Follow-up controls ................................................................................................. 34

5.10 Optimization control ............................................................................................... 34

5.11 Monitoring parallel positioning of amplifiers ............................................................ 34

5.12 Provision of actuating energy ................................................................................. 34

5.12.1 General ..................................................................................................... 34

5.12.2 System with an accumulator ....................................................................... 35

5.12.3 Systems without accumulator ..................................................................... 38

5.12.4 Direct electric positioner ............................................................................ 39

5.12.5 Recommendation for hydraulic fluid selection ............................................. 40

5.13 Power supply for electronic control systems ........................................................... 40

5.14 Operational transitions ........................................................................................... 40

5.14.1 Start-up and synchronization ...................................................................... 40

5.14.2 Normal shutdown ....................................................................................... 41

5.14.3 Sudden load rejection ................................................................................ 41

5.14.4 Other operational transitions ...................................................................... 42

5.15 Safety devices/circuits ........................................................................................... 42

5.15.1 General ..................................................................................................... 42

5.15.2 Quick shutdown and emergency shutdown ................................................. 42

5.15.3 Overspeed protection device ...................................................................... 43

5.15.4 Interlocks ................................................................................................... 43

5.16 Supplementary equipment ..................................................................................... 43

5.16.1 Measures to reduce pressure variations ..................................................... 43

5.16.2 Surge control ............................................................................................. 43

5.16.3 Equipment and measures to lower the speed rise ....................................... 44

5.16.4 Central flow rate control in river power station systems ............................... 44

5.16.5 Brakes ....................................................................................................... 44

5.16.6 Synchronous condenser mode of operation ................................................ 45

5.17 Environmental suitability of governor components .................................................. 45

5.17.1 Vibration and shock resistance ................................................................... 45

5.17.2 Temperature and humidity ......................................................................... 45

5.18 Electromagnetic compatibility ................................................................................. 45

6 How to apply the recommendations ................................................................................. 45

Annex A (normative) Simplified differential equations and transfer functions of idealized

PID-controllers ...................................................................................................................... 58

Annex B (informative) Grid frequency control ........................................................................ 60

Annex C (informative) Quick shutdown and emergency shutdown ......................................... 63

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SIST EN 61362:2012
– 4 – 61362 © IEC:2012

Figure 1 – Controlled variable range ...................................................................................... 12

Figure 2 – Permanent droop .................................................................................................. 12

Figure 3 – Proportional action coefficient and integral action time .......................................... 13

Figure 4 – Derivative time constant ....................................................................................... 14

Figure 5 – Dead band ............................................................................................................ 15

Figure 6 – Minimum servomotor opening/closing time ............................................................ 16

Figure 7 – Time constant of the servo-positioner ................................................................... 16

Figure 8 – Servo-positioner inaccuracy .................................................................................. 17

Figure 9 – Control system dead time ..................................................................................... 17

Figure 10 – Control system with speed and power output controllers in parallel ...................... 21

Figure 11 – Control system with speed controller and power command signal in parallel ........ 21

Figure 12 – Control system with speed controller and water level controller in parallel ........... 21

Figure 13 – Governing system with power output and speed controller in series .................... 22

Figure 14 – Governing system with water level controller and speed controller in series ......... 22

Figure 15 – Power output control via the speed controller ...................................................... 22

Figure 16 – Water level controller without speed controller .................................................... 23

Figure 17 – Parallel structure with defined functional relation and an additional signal

superimposition ..................................................................................................................... 24

Figure 18 – Series structure with defined functional relation and additional signal

superimposition ..................................................................................................................... 24

Figure 19 – Time step response and frequency response of the amplifier output Y/Y

max

to a displacement input s ..................................................................................................... 30

Figure 20 – Pressure tank content and pressure ranges ........................................................ 35

Figure 21 – Open-circuit system ............................................................................................ 39

Figure 22 – Start-up speed curve up to synchronization ......................................................... 41

Figure 23 – Load rejection ..................................................................................................... 42

Figure A.1 – Idealized PID in pure parallel structure............................................................... 59

Figure A.2 – Idealized PID alternative representation ............................................................. 59

Figure B.1 – Example of principle schematic functional diagram of a unit with a turbine

governing system using an idealized PID controller with a power droop .................................. 61

Figure B.2 – Behaviour of two units with different governor permanent droop values .............. 62

Table C.1 – Alternative I – Summary of cases for quick shut-down and emergency shut-

down ..................................................................................................................................... 65

Table C.2 – Alternative II – Summary of cases for quick shut-down and emergency shut-

down ..................................................................................................................................... 66

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SIST EN 61362:2012
61362 © IEC:2012 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDE TO SPECIFICATION OF HYDRAULIC TURBINE
GOVERNING SYSTEMS
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 61362 has been prepared by IEC technical committee 4: Hydraulic

turbines.

This second edition cancels and replaces the first edition published in 1998. It is a technical

revision. It takes into account the experience with the guide during the last decade as well as

the progress in the state of the art of the underlying technologies.
The text of this standard is based on the following documents:
FDIS Report on voting
4/270/FDIS 4/272/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.

---------------------- Page: 11 ----------------------
SIST EN 61362:2012
– 6 – 61362 © IEC:2012

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.
---------------------- Page: 12 ----------------------
SIST EN 61362:2012
61362 © IEC:2012 – 7 –
INTRODUCTION

While a standard for the testing of hydraulic turbine governing systems had been existing for a

very long time (IEC 60308 published in 1970) , a guide for the specification of hydraulic turbine

governing systems was missing until 1998. The need for such a guide became more and more

urgent with the fast development and the new possibilities especially of the digital components

of the governor.

The current second edition of the guide takes into account the experience with the guide during

the last decade as well as the progress in the state of the art of the underlying technologies.

While the first edition was written more or less as a supplement to the already existing guide

for testing, the objective of the second edition is to be the leading guide with respect to turbine

governing systems.
________

IEC 60308:1970, International code for testing of speed governing systems for hydraulic turbines. This

publication was withdrawn and replaced by IEC 60308:2005.
---------------------- Page: 13 ----------------------
SIST EN 61362:2012
– 8 – 61362 © IEC:2012
GUIDE TO SPECIFICATION OF HYDRAULIC TURBINE
GOVERNING SYSTEMS
1 Scope

This International Standard includes relevant technical data necessary to describe hydraulic

turbine governing systems and to define their performance. It is aimed at unifying and thus

facilitating the selection of relevant parameters in bidding specifications and technical bids. It

will also serve as a basis for setting up technical guarantees.

The scope of this standard is restricted to the turbine governing level. Additionally some

remarks about the control loops of the plant level and about primary and secondary frequency

control (see also Annex B) are made for better understanding without making a claim to be

complete.
Important topics covered by the guide are:

– speed, power, water level, opening and flow (discharge) control for reaction and impulse-

type turbines including double regulated machines;
– means of providing actuating energy;
– safety devices for emergency shutdown, etc.

To facilitate the setting up of specifications, this guide also includes data sheets, which are to

be filled out by the customer and the supplier in the various stages of the project and the

contract.

Acceptance tests, specific test procedures and guarantees are outside the scope of the guide;

those topics are covered by IEC 60308.
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 60050-351:2006, International Electrotechnical Vocabulary – Part 351: Control technology

IEC 60068-2-6:2007, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)

IEC 60068-2-27:2008, Environmental testing – Part 2-27: Tests – Test Ea and guidance: Shock

IEC 60308:2005, Hydraulic turbines – Testing of control systems
IEC 61000-4-1:2006, Electromagnetic compatibility (EMC) – Part 4-1: Testing and
measurement techniques – Overview of IEC 61000-4 series

CISPR 11:2009, Industrial, scientific and medical equipment – Radio-frequency disturbance

characteristics – Limits and methods of measurement
ISO 3448:1992, Industrial liquid lubricants – ISO viscosity classification
---------------------- Page: 14 ----------------------
SIST EN 61362:2012
61362 © IEC:2012 – 9 –
...

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