EN 62551:2012
(Main)Analysis techniques for dependability - Petri net techniques
Analysis techniques for dependability - Petri net techniques
IEC 62551:2012 provides guidance on a Petri net based methodology for dependability purposes. It supports modelling a system, analysing the model and presenting the analysis results. This methodology is oriented to dependability-related measures with all the related features, such as reliability, availability, production availability, maintainability and safety (e.g. safety integrity level (SIL) [2] related measures). Key words: Petri net based methodology for dependability purposes
Analysemethoden für Zuverlässigkeit - Petrinetze
Techniques d'analyse de sûreté de fonctionnement - Techniques des réseaux de Petri
La CEI 62551:2012 donne des directives pour une technique basée sur les réseaux de Petri dans le domaine de la sûreté de fonctionnement. Elle porte sur la modélisation d'un système, l'analyse du modèle et la présentation des résultats de l'analyse. Cette méthode est orientée vers les mesures relatives à la sûreté de fonctionnement avec toutes les caractéristiques associées, telles que la fiabilité, la disponibilité, la disponibilité de production, la maintenabilité et la sécurité (par exemple, les mesures associées au niveau d'intégrité de sécurité (SIL[2]: en anglais:system integrity level). Mots clés: technique basée sur les réseaux de Petri dans le domaine de la sûreté de fonctionnement
Tehnike analize zagotovljivosti - Tehnike Petrijeve mreže
Ta mednarodni standard podaja smernice o metodologiji, ki temelji na Petrijevi mreži, za namene zagotovljivosti. Podpira modeliranje sistema, analizo modela in predstavitev rezultatov analize. Ta metodologija je usmerjena v ukrepe v zvezi z zagotovljivostjo z vsemi zadevnimi lastnostmi, kot je zanesljivost, razpoložljivost, razpoložljivost proizvodnje, sposobnost vzdrževanja in varnost (npr. ukrepi v zvezi z 2. stopnjo varnostne celovitosti (SIL)). Ta standard obravnava naslednje teme na področju Petrijevih mrež: a) opredelitev bistvenih izrazov in simbolov ter opis njihove uporabe in metod za grafično predstavitev; b) pregled terminologije in njene povezave z zagotovljivostjo; c) predstavitev načela postopnosti za 1) modeliranje zagotovljivosti s Petrijevimi mrežami, 2) navodila za uporabo tehnik, ki temeljijo na Petrijevi mreži, za kvalitativne in kvantitativne analize zagotovljivosti, 3) predstavitev in razlaganje rezultatov analize; d) opis povezave med Petrijevimi mrežami in drugimi tehnikami modeliranja; e) navedbo praktičnih primerov. Ta standard ne podaja smernic za reševanje matematičnih problemov, ki nastanejo pri analizi Petrijeve mreže; take smernice so navedene v točkah [3] in [4]. Ta standard se uporablja v vseh industrijah, v katerih se izvajajo kvalitativne in kvantitativne analize zagotovljivosti.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-2013
Tehnike analize zagotovljivosti - Tehnike Petrijeve mreže
Analysis techniques for dependability - Petri net techniques
Techniques d'analyse de sûreté de fonctionnement - Techniques des réseaux de Petri
Ta slovenski standard je istoveten z: EN 62551:2012
ICS:
21.020 =QDþLOQRVWLLQQDþUWRYDQMH Characteristics and design of
VWURMHYDSDUDWRYRSUHPH machines, apparatus,
equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN 62551
NORME EUROPÉENNE
November 2012
EUROPÄISCHE NORM
ICS 21.020
English version
Analysis techniques for dependability -
Petri net techniques
(IEC 62551:2012)
Techniques d'analyse de sûreté de Analysemethoden für Zuverlässigkeit -
fonctionnement - Petrinetze
Techniques des réseaux de Petri (IEC 62551:2012)
(CEI 62551:2012)
This European Standard was approved by CENELEC on 2012-11-06. 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 62551:2012 E
Foreword
The text of document 56/1476/FDIS, future edition 1 of IEC 62551, prepared by IEC/TC 56
"Dependability" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
(dop) 2013-08-06
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2015-11-06
• latest date by which the national
standards conflicting with the
document have to be withdrawn
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 62551:2012 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 61508 Series NOTE Harmonised as EN 61508 Series (not modified).
IEC 61508-4:2010 NOTE Harmonised as EN 61508-4:2010 (not modified).
IEC 61508-1:2010 NOTE Harmonised as EN 61508-1:2010 (not modified).
IEC 61165:2006 NOTE Harmonised as EN 61165:2006 (not modified).
IEC 60812:2006 NOTE Harmonised as EN 60812:2006 (not modified).
IEC 61025:2006 NOTE Harmonised as EN 61025:2007 (not modified).
IEC 61078:2006 NOTE Harmonised as EN 61078:2006 (not modified).
IEC 61511-3:2003 NOTE Harmonised as EN 61511-3:2004 (not modified).
IEC 61703:2001 NOTE Harmonised as EN 61703:2002 (not modified).
- 3 - EN 62551:2012
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 60050-191 1990 International Electrotechnical Vocabulary - -
(IEV) -
Chapter 191: Dependability and quality
of service
IEC 62551 ®
Edition 1.0 2012-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Analysis techniques for dependability – Petri net techniques
Techniques d'analyse de sûreté de fonctionnement – Techniques des réseaux
de Petri
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XB
ICS 21.020 ISBN 978-2-83220-370-5
– 2 – 62551 © IEC:2012
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, symbols and abbreviations . 8
3.1 Terms and definitions . 8
3.2 Symbols and abbreviations . 10
4 General description of Petri nets . 12
4.1 Untimed low-level Petri nets . 12
4.2 Timed low-level Petri nets . 12
4.3 High-level Petri nets . 13
4.4 Extensions of Petri nets and modelling with Petri nets . 13
4.4.1 Further representations of Petri net elements . 13
4.4.2 Relationship to the concepts of dependability . 14
5 Petri net dependability modelling and analysis. 15
5.1 The steps to be performed in general . 15
5.2 Steps to be performed in detail . 16
5.2.1 General . 16
5.2.2 Description of main parts and functions of the system (Step 1) . 16
5.2.3 Modelling the structure of the system on the basis of Petri net-
submodels and their relations (Step 2). 16
5.2.4 Refining the models of Step 2 until the required level of detail is
achieved (Step 3) . 18
5.2.5 Analysing the model to achieve the results of interest (Step 4) . 18
5.2.6 Representation and interpretation of results of analyses (Step 5) . 19
5.2.7 Summary of documentation (Step 6) . 20
6 Relationship to other dependability models . 20
Annex A (informative) Structure and dynamics of Petri nets . 22
Annex B (informative) Availability with redundancy m-out-of-n . 33
Annex C (informative) Abstract example . 39
Annex D (informative) Modelling typical dependability concepts . 43
Annex E (informative) Level-crossing example . 45
Bibliography . 62
Figure 1 – Weighted inhibitor arc . 13
Figure 2 – Place p is a multiple place . 14
Figure 3 – Marking on p after firing of transition t . 14
Figure 4 – The activation of t depends on the value of V . 14
Figure 5 – Methodology consisting mainly of ‘modelling’, ‘analysing’ and ‘representing’
steps. 15
Figure 6 – Process for dependability modelling and analysing with Petri nets . 15
Figure 7 – Modelling structure concerning the two main parts 'plant' and 'control' with
models for their functions and dependability . 17
Figure 8 – Indication of the analysis method as a function of the PN model . 19
62551 © IEC:2012 – 3 –
Figure A.1 – Availability state-transition circle of a component . 22
Figure A.2 – Transition ‘failure’ is enabled . 23
Figure A.3 – ‘Faulty’ place marked due to firing of ‘failure' . 23
Figure A.4 – Transition ‘comp repair’ is enabled . 24
Figure A.5 – The token at the ‘maintenance crew available’ location is not used . 24
Figure A.6 – Transition is not enabled . 25
Figure A.7 – Marking before firing . 25
Figure A.8 – Marking after firing . 25
Figure A.9 – PN with initial marking . 25
Figure A.10 – Corresponding RG . 25
Figure A.11 – Transitions ‘comp repair’ and ‘comp failure’ are enabled . 26
lp hp
Figure A.12 – Marking after firing of transition ‘comp repair’ . 27
lp
Figure A.13 – A timed PN with two exponentially distributed timed transitions . 28
Figure A.14 – The corresponding stochastic reachability graph . 28
Figure A.15 – Petri net with timed transitions . 29
Figure B.1 – Two individual item availability nets with specific failure- and repair-rates . 33
Figure B.2 – Stochastic reachability graph corresponding to Figure B.1 with global
states (as an abbreviation c is used for “comp faulty”) . 33
1 1
Figure B.3 – Three individual item availability nets with specific failure rates and repair
rates . 33
Figure B.4 – Stochastic reachability graph corresponding to Figure B.3 with global
states (as an abbreviation c is used for ‘comp faulty’) . 34
Figure B.5 – Specifically connected 1-out-of-3 availability net . 35
Figure B.6 – Specifically connected 2-out-of-3 availability net . 35
Figure B.7 – Specifically connected 3-out-of-3 availability net . 36
Figure B.8 – Stochastic reachability graph with system specific operating states . 36
Figure B.9 – Specifically connected 1-out-of-3 reliability net . 37
Figure B.10 – Reachability graph for the net in Figure B.9 . 37
Figure B.11 – Specifically connected 2-out-of-3 reliability net . 37
Figure B.12 – Reachability graph for the net in Figure B.11 . 37
Figure B.13 – Specifically connected 3-out-of-3 reliability net . 38
Figure B.14 – Reachability graph for the net in Figure B.13 .
...
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