Functional safety
Designing safety-related electrical control systems to meet IEC 62061
3-Day Training Course
Course description:
This in-depth course covers the functional safety of machinery in accordance with the IEC 62061 standard. It is aimed at those involved in the design of systems, subsystems or elements that are used to perform Safety Related Control Functions (SRCFs) and need to achieve a Safety Integrity Level (SIL 1 to 3).
The course starts with typical examples of SRCFs used in modern industrial machinery and how the required performance (SIL) of these functions is determined. The course is based on the IEC 62061 standard to show how the safety integrity is achieved through following a systematic lifecycle of design, analysis, verification and validation. The introductory session is suitable for a wider audience just needing an overview.
Reliability principles are clearly explained and practical exercises are performed to show how failure rates and modes can be determined and used, together with defined architectures, to establish the overall SIL.
Target audience:
The course is intended for engineers (electrical/electronic/mechanical) who are designing and integrating Safety Related Electrical Control Systems (SRECS) and those in the associated project management and quality roles.
Learning outcomes:
Participants gain a thorough overview of IEC 62061 and are shown how to demonstrate evidence of compliance for each phase of the lifecycle, including SIL determination, design and integration requirements, architectural and reliability analyses, verification and validation, user documentation and the management of functional safety for the project.
Supporting material:
Examples of Reliability Block Diagrams, Failure Modes and Effects Analysis (FMEA) and practical SIL assessments show how the methodologies work. Exercises are performed by the participants working either individually or as a group led by the trainer.
Each attendee receives a manual based on the lecture slides, supplementary hand-outs, templates, checklists and a certificate of attendance for each individual’s training record. Frequent question and answer sessions are included for clarification.
Course Outline
DAY 1: FUNCTIONAL SAFETY PRINCIPLES
This day introduces the key principles and concepts of functional safety and Safety Integrity Levels, plus the basic reliability theory and modelling on which hardware safety integrity is built. The sessions covered in the following days assume an understanding of the basic principles covered in Day 1, which are also fundamental to developing core competence in functional safety.
• The need to quantify risk and safety integrity
• Safety functions, E/E/PE systems, SIL and relationship with PL
• Random hardware and systematic failures
• IEC 62061 overview and relationship with other standards
• Understanding the jargon
• Information required to specify the SRCFs
• Functional and safety integrity requirements specification
• SIL assignment method from IEC 62061 Annex A
• PRACTICAL EXERCISE: SIL Determination
• Basic terms and their relationships: MTBF, λ, MTTF, PFD, PFH, MTTR, T
• Reliability functions and equations
• Types of failure (safe, dangerous, diagnosed, etc)
• Reliability Block Diagrams
• Assumptions
• PRACTICAL EXERCISE: Creating a RBD model and failure rate calculations
• Choosing component failure rate sources (field data or predictive model)
• Allocating failure modes and judging diagnostics coverage
• Verifying the FMEDA and judgements used
• PRACTICAL EXERCISE: Perform FMEDA (group exercise)
• ‘Simple’ and ‘complex’ elements
• Architectural constraints (HFT and SFF) and systematic constraints
• PRACTICAL EXERCISE: Identifying SILCL from given scenarios
DAY 2: HARDWARE DESIGN AND ANALYSIS FROM IEC 62061
The scope of Day 2 is concerned with the specific requirements from IEC 62061 for the hardware design and analysis of the SRECS, subsystems and elements.
• Selection: pre-design or develop
• Avoidance of systematic failures
• Control of systematic faults
• EM immunity
• System architecture
• Mapping of function blocks to subsystems
• Defining the SIL of the SRECS
• PRACTICAL EXERCISE: Define function bocks and allocate to subsystems
• Subsystem design and architectural constraints
• Requirements for elements, pre-designed or develop
• Safe failure fraction (SFF)
• Estimation of the system dangerous failure rate
• PRACTICAL EXERCISE: Review and selection of elements (from datasheets)
• PFH calculations for specified architectures
• Estimating common cause failure (CCF) and Annex F
• PRACTICAL EXERCISE: Calculating PFH and assess CCF
• Requirements for the control of systematic failures
• Realisation of diagnostic functions
• Testing the diagnostic functions
• PRACTICAL EXERCISE: Identifying diagnostics requirements
DAY 3: SOFTWARE, LIFECYCLE, DOCUMENTATION AND FUNCTIONAL SAFETY MANAGEMENT
The scope of Day 3 is about the software and the methods prescribed by IEC 62061 that are to be used during the realisation activities to ensure the systematic safety integrity is achieved, such as verification, validation, modification, management of functional safety, etc.
• Embedded software (FVL) considerations
• Application software (LVL) considerations
• Configuration management
• Tool chain considerations
• Application software design, integration and testing
• Integration: general and test requirements
• Validation: analytical and testing requirements
• Modification process
• PRACTICAL EXERCISE: Performing an impact analysis
• Scope and examples of documentation
• SRECS design documentation
• SRECS user documentation for installation, use and maintenance
• PRACTICAL EXERCISE: Creating a document index from a given lifecycle
• FSM essentials: policy, strategy, roles and responsibilities, etc
• Verification and Validation plans
• Review, approval and control procedures
• Management of supply chain, quality plans and liaison with customers
• Management of competence and guidance for job roles
• PRACTICAL EXERCISE: Develop safety and quality plan with lifecycle stages
• Optional: Specific project concerns / discussion about practical application
• Feedback
Contact Silmetric:
Courses are normally delivered at the customer’s site. For prices and availability please contact us at info@silmetric.com or call +44(0)1244 457671