SVENSK STANDARD SS ISO :2010

Transkript

1 SVENSK STANDARD SS ISO :2010 Fastställd/Approved: Publicerad/Published: Utgåva/Edition: 1 Språk/Language: engelska/english ICS: ; Traktorer och maskiner för lantbruk och skogsbruk Säkerhetsrelaterade delar av styrsystem Del 2: Begreppsfas (ISO :2010, IDT) Tractors and machinery for agriculture and forestry Safety related parts of control systems Part 2: Concept phase (ISO :2010, IDT)

2 Standarder får världen att fungera SIS (Swedish Standards Institute) är en fristående ideell förening med medlemmar från både privat och offentlig sektor. Vi är en del av det europeiska och globala nätverk som utarbetar internationella standarder. Standarder är dokumenterad kunskap utvecklad av framstående aktörer inom industri, näringsliv och samhälle och befrämjar handel över gränser, bidrar till att processer och produkter blir säkrare samt effektiviserar din verksamhet. Delta och påverka Som medlem i SIS har du möjlighet att påverka framtida standarder inom ditt område på nationell, europeisk och global nivå. Du får samtidigt tillgång till tidig information om utvecklingen inom din bransch. Ta del av det färdiga arbetet Vi erbjuder våra kunder allt som rör standarder och deras tillämpning. Hos oss kan du köpa alla publikationer du behöver allt från enskilda standarder, tekniska rapporter och standardpaket till handböcker och onlinetjänster. Genom vår webbtjänst e nav får du tillgång till ett lättnavigerat bibliotek där alla standarder som är aktuella för ditt företag nns tillgängliga. Standarder och handböcker är källor till kunskap. Vi säljer dem. Utveckla din kompetens och lyckas bättre i ditt arbete Hos SIS kan du gå öppna eller företagsinterna utbildningar kring innehåll och tillämpning av standarder. Genom vår närhet till den internationella utvecklingen och ISO får du rätt kunskap i rätt tid, direkt från källan. Med vår kunskap om standarders möjligheter hjälper vi våra kunder att skapa verklig nytta och lönsamhet i sina verksamheter. Vill du veta mer om SIS eller hur standarder kan effektivisera din verksamhet är du välkommen in på eller ta kontakt med oss på tel Standards make the world go round SIS (Swedish Standards Institute) is an independent non profit organisation with members from both the private and public sectors. We are part of the European and global network that draws up international standards. Standards consist of documented knowledge developed by prominent actors within the industry, business world and society. They promote cross border trade, they help to make processes and products safer and they streamline your organisation. Take part and have inuence As a member of SIS you will have the possibility to participate in standardization activities on national, European and global level. The membership in SIS will give you the opportunity to inuence future standards and gain access to early stage information about developments within your eld. Get to know the nished work We offer our customers everything in connection with standards and their application. You can purchase all the publications you need from us everything from individual standards, technical reports and standard packages through to manuals and online services. Our web service e nav gives you access to an easy to navigate library where all standards that are relevant to your company are available. Standards and manuals are sources of knowledge. We sell them. Increase understanding and improve perception With SIS you can undergo either shared or in house training in the content and application of standards. Thanks to our proximity to international development and ISO you receive the right knowledge at the right time, direct from the source. With our knowledge about the potential of standards, we assist our customers in creating tangible benet and protability in their organisations. If you want to know more about SIS, or how standards can streamline your organisation, please visit or contact us on phone +46 (0)

3 Den internationella standarden ISO :2010 gäller som svensk standard. Detta dokument innehåller den officiella engelska versionen av ISO :2010. The International Standard ISO :2010 has the status of a Swedish Standard. This document contains the official English version of ISO :2010. Copyright/Upphovsrätten till denna produkt tillhör SIS, Swedish Standards Institute, Stockholm, Sverige. Användningen av denna produkt regleras av slutanvändarlicensen som åternns i denna produkt, se standardens sista sidor. Copyright SIS, Swedish Standards Institute, Stockholm, Sweden. All rights reserved. The use of this product is governed by the end user licence for this product. You will nd the licence in the end of this document. Upplysningar om sakinnehållet i standarden lämnas av SIS, Swedish Standards Institute, telefon Standarder kan beställas hos SIS Förlag AB som även lämnar allmänna upplysningar om svensk och utländsk standard. Information about the content of the standard is available from the Swedish Standards Institute (SIS), telephone Standards may be ordered from SIS Förlag AB, who can also provide general information about Swedish and foreign standards. Denna standard är framtagen av kommittén för Lantbruksmaskiner, SIS/TK 228. Har du synpunkter på innehållet i den här standarden, vill du delta i ett kommande revideringsarbete eller vara med och ta fram andra standarder inom området? Gå in på där hittar du mer information.

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5 ISO :2010(E) Contents Page Foreword...iv Introduction...v 1 Scope Normative references Terms and definitions Abbreviated terms Concept Unit of observation Objectives Prerequisites Requirements Work products Risk analysis and method description Objectives Prerequisites Requirements Work products System design Objectives Prerequisites Requirements Work products...10 Annex A (normative) Designated architectures for SRP/CS...11 Annex B (informative) Simplified method to estimate channel MTTF dc...17 Annex C (informative) Determination of diagnostic coverage (DC)...20 Annex D (informative) Estimates for common cause failure (CCF)...24 Annex E (informative) Systematic failure...26 Annex F (informative) Characteristics of safety functions...29 Annex G (informative) Example of a risk analysis...32 Bibliography...37 ISO 2010 All rights reserved iii

6 ISO :2010(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO was prepared by Technical Committee ISO/TC 23, Tractors and machinery for agriculture and forestry, Subcommittee SC 19, Agricultural electronics. ISO consists of the following parts, under the general title Tractors and machinery for agriculture and forestry Safety related parts of control systems: Part 1: General principles for design and development Part 2: Concept phase Part 3: Series development, hardware and software Part 4: Production, operation, modification and supporting processes iv ISO 2010 All rights reserved

7 ISO :2010(E) Introduction ISO sets out an approach to the design and assessment, for all safety life cycle activities, of safety relevant systems comprising electrical and/or electronic and/or programmable electronic components (E/E/PES) on tractors used in agriculture and forestry, and on self propelled ride on machines and mounted, semi mounted and trailed machines used in agriculture. It is also applicable to municipal equipment. It covers the possible hazards caused by the functional behaviour of E/E/PES safety related systems, as distinct from hazards arising from the E/E/PES equipment itself (electric shock, fire, nominal performance level of E/E/PES dedicated to active and passive safety, etc.). The control system parts of the machines concerned are frequently assigned to provide the critical functions of the safety related parts of control systems (SRP/CS). These can consist of hardware or software, can be separate or integrated parts of a control system, and can either perform solely critical functions or form part of an operational function. In general, the designer (and to some extent, the user) will combine the design and validation of these SRP/CS as part of the risk assessment. The objective is to reduce the risk associated with a given hazard (or hazardous situation) under all conditions of use of the machine. This can be achieved by applying various protective measures (both SRP/CS and non SRP/CS) with the end result of achieving a safe condition. ISO allocates the ability of safety related parts to perform a critical function under foreseeable conditions into five performance levels. The performance level of a controlled channel depends on several factors, including system structure (category), the extent of fault detection mechanisms (diagnostic coverage), the reliability of components (mean time to dangerous failure, common cause failure), design processes, operating stress, environmental conditions and operation procedures. Three types of failures are considered: systematic, common cause and random. In order to guide the designer during design, and to facilitate the assessment of the achieved performance level, ISO defines an approach based on a classification of structures with different design features and specific behaviour in case of a fault. The performance levels and categories can be applied to the control systems of all kinds of mobile machines: from simple systems (e.g. auxiliary valves) to complex systems (e.g. steer by wire), as well as to the control systems of protective equipment (e.g. interlocking devices, pressure sensitive devices). ISO adopts a customer risk based approach for the determination of the risks, while providing a means of specifying the target performance level for the safety related functions to be implemented by E/E/PES safety related channels. It gives requirements for the whole safety life cycle of E/E/PES (design, validation, production, operation, maintenance, decommissioning), necessary for achieving the required functional safety for E/E/PES that are linked to the performance levels. ISO 2010 All rights reserved v

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9 Tractors and machinery for agriculture and forestry Safety related parts of control systems Part 2: Concept phase 1 Scope This part of ISO specifies the concept phase of the development of safety related parts of control systems (SRP/CS) on tractors used in agriculture and forestry, and on self propelled ride on machines and mounted, semi mounted and trailed machines used in agriculture. It can also be applied to municipal equipment (e.g. street sweeping machines). It specifies the characteristics and categories required of SRP/CS for carrying out their safety functions. This part of ISO is applicable to the safety related parts of electrical/electronic/programmable electronic systems (E/E/PES). As these relate to mechatronic systems, it does not specify which safety functions or categories are to be used in a particular case. It is not applicable to non E/E/PES systems (e.g. hydraulic, mechanic or pneumatic). 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. ISO :2010, Tractors and machinery for agriculture and forestry Safety related parts of control systems Part 1: General principles for design and development ISO :2010, Tractors and machinery for agriculture and forestry Safety related parts of control systems Part 3: Series development, hardware and software 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO apply. 4 Abbreviated terms For the purposes of this document, the following abbreviated terms apply. ADC AgPL AgPL r analogue to digital converter agricultural performance level required agricultural performance level ISO 2010 All rights reserved 1

10 ISO :2010(E) CAD Cat CCF CRC DC DC avg ECU ETA E/E/PES EMC EUC FMEA FMECA EPROM FSM FTA HAZOP HIL MTTF MTTF d MTTF dc PES QM RAM SOP SRL SRP SRP/CS SRS computer aided design hardware category common cause failure cyclic redundancy check diagnostic coverage average diagnostic coverage electronic control unit event tree analysis electrical/electronic/programmable electronic systems electromagnetic compatibility equipment under control failure mode and effects analysis failure mode effects and criticality analysis erasable programmable read only memory functional safety management fault tree analysis hazard and operability study hardware in the loop mean time to failure mean time to dangerous failure mean time to dangerous failure for each channel programmable electronic system quality measures random access memory start of production software requirement level safety related parts safety related parts of control systems safety related system 2 ISO 2010 All rights reserved

11 ISO :2010(E) 5 Concept Unit of observation 5.1 Objectives The objective of this phase is to develop an adequate understanding of the unit of observation in order to satisfactorily complete all of the tasks defined in the safety life cycle. On the basis of the chosen safety concept, a suitable method should be used to determine the required performance level. Suitable methods include risk analysis (described below), other standards, legal requirements and test body expertise. 5.2 Prerequisites The necessary prerequisites are a description of the unit of observation, its interfaces, already known safety and reliability requirements and the scope of application 5.3 Requirements Unit of observation and ambient conditions A safety related concept shall include the following: a) the scope, context and purpose of the unit of observation; b) functional requirements for the unit of observation; c) other requirements regarding the unit of observation and ambient conditions, including technical or physical requirements, e.g. operating, environmental and surrounding conditions and constraints, and legal requirements, especially safety related legislation, regulations and standards (national and international); d) historical safety and reliability requirements and the level of safety and reliability achieved for similar or related units of observation Limits of unit of observation and its interfaces with other units of observation The following information shall be considered in order to gain an understanding of the operation of the unit of observation in its environment: the limits of the unit of observation; its interfaces and interactions with other units of observation and components; requirements regarding other units of observation; mapping and allocation of relevant functions to involved units of observation Sources of stress The sources of stress which could affect the safety and reliability of the unit of observation shall be determined, including the following: the interaction of different units of observation; hazards of a physical or chemical nature (energy content, toxicity, explosiveness, corrosiveness, reactivity, combustibility, etc.); ISO 2010 All rights reserved 3