Implementation and application of EN ISO

Transcription

1 Berthold Heinke Implementation and application of EN ISO Safety-related control systems Safe machines in Europe

2 Complete one-stop solutions for safe automation Faster, more flexible, safer with this objective in mind, the level of automation on plant and machinery continues to advance in all industries. As a complete supplier for control and safety technology, Pilz is a company whose name is synonymous worldwide with safety for man, machine and the environment, providing one-stop automation solutions for all industries. Our range is as follows: Sensor technology Control technology Networks Drive technology Operator and visualisation systems Software Automation system PSS 4000 Consulting and engineering Training Do you have questions about machine safety? We ve got the answer:

3 Implementation and application of EN ISO Safety-related control systems Safe machines in Europe Berthold Heinke

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5 Pilz the spirit of safety The protection of people, material assets and the environment commonly referred to by the word safety is a high-minded ideal. With increasing manufacturing output and industrialisation, plus higher levels of automation, its importance is more likely to grow in future than to decline. It is a sad fact that safety measures are more likely to be conspicuous by their absence, e.g. following an accident, than by their presence. However, safety is not a fixed constant, but as an accepted residual risk it is dependent on such factors as the standard of technology and the cultural context. It is not even regarded as a known quantity in people s lives. People call for a safe workplace during the day, for example, and enjoy taking calculable risks in their leisure time activities. Pilz has been committed to safety since the launch of the first two-hand control products in 1968 and demonstrates this time and again through regular input on standardisation committees and through innovative products. Safety is a European issue today, enshrined and enunciated in rulings like the Machinery Directive. EN has been the applicable standard until now in terms of verifying the compliance of safety-related parts of control systems with the general health and safety requirements set out in the Machinery Directive. Introduced back in 1996, this standard was relevant to the technology of the day and covered the use of electromechanical and pneumatic components. It has been succeeded by the harmonised standards EN ISO and EN IEC They define the current standard of technology. In contrast to the deterministic approach adopted by EN 954-1, the basis of EN ISO and EN IEC is probabilistic in nature. This takes account of the probability of a fault occurring which may entail the failure of the safety function. The categories defined are Performance Level (PL) or Safety Integrity Level (SIL). This is the first time that an applied engineering resource has been available which helps design engineers and users to find the right solution. Knowledge and application of EN ISO are essential, and the purpose of this brochure is to facilitate both. For those wishing to engage further and in greater depth, Pilz also offers the design and validation tool PAScal, comprehensive training courses and a broad range of services, from plant assessment right through to risk assessment. Ask us. Klaus Stark General Manager International Operations, Pilz GmbH & Co. KG

6 Not everyone s a mathematical genius... and needn t be thanks to PAScal and its simple approach to calculation and safety function design conforming to EN ISO and EN/IEC The software tool developed by Pilz, the PAScal Safety Calculator, calculates and verifies the key safety parameters for safety functions on plant and machinery, such as Performance Level (PL) and Safety Integrity Level (SIL). The calculation is based on the harmonised safety standards EN ISO and EN/IEC The result is compared with the safety parameters required for the safety functions and is displayed in graphic form. It is then easy to ascertain the influence of the individual components on the various safety functions. Given its systematic approach, the PAScal Safety Calculator facilitates the safety evaluation process in conformity with the current norms. The tool offers even more practical relevance with improved libraries containing the safety ratings for all Pilz products and for products of other manufacturers taken from Sistema (IFA software utility). PAScal is therefore quick and easy to use with reference to different manufacturers. Tool-based design of safety functions Although a knowledge of EN ISO is required for the evaluation of safety functions, and for the calculation of the Performance Levels of the individual safety functions associated therewith, nevertheless the practical application is not always straightforward. Without tested and certified calculation tools, which reproduce the formulae and criteria of EN ISO , it is still necessary for the engineer to provide evidence that not only were the correct formulae applied but that the calculations themselves were carried out correctly. Tools also provide the facility for processing entire parts libraries of different manufacturers without having to re-enter the safety specifications. This drastically reduces the probability of errors and also keeps the time required for the calculations down to a minimum.

7 Calculating with PAScal The PAScal Safety Calculator is a Windows -based tool which permits the validation of safety functions with reference to EN ISO and EN/IEC It is possible, using a graphic editor, to model safety functions and to define their structure and the usage pattern of the individual components. Given the extensive library functions, it is possible for users to import machine data in the standard library formats or to create and manage their own libraries. Multilingual reports can be generated for projects at no additional cost due to the fact that it supports six languages. But how does this work in practical terms? Step 1 Create new project The first step is to input the general project or machine data. This can be based on a set operating sequence or alternatively it can be directly entered in a project management utility. The version can be tracked both via an automatic track change facility with current date and via a user-definable version number.

8 Step 2 Safety functions The safety functions relating to all the risks are then entered step by step. This involves naming the safety functions, describing their function and either entering the required PLr if already identified in the course of a risk assessment or consulting the risk graph to identify the PLr. Step 3 Model safety functions

9 The individual safety functions are then modelled on the basis of data taken from the available circuit diagrams. The libraries are so extensive that components rarely have to be entered by users. The drag and drop function is mostly used to take them from the libraries and enter them in the editor view. There is a search function to help identify the correct components because it is not always easy as the number of libraries and components gradually increases. It is only necessary to select between the various versions or applications of a machine after the basic machine selection has been made. Whenever necessary, it is possible to add documents, diagrams, circuit diagrams or other documents in order to elucidate or illustrate the assessment. There is an integrated conversion tool which can be of assistance when dealing with components where the levels of wear depend on a number of operating cycles, helping to calculate these values from the information normally available. The display is selective, indicating specifically which data are required for the relevant machine or for the relevant structure. Naturally the program also supports CCF analysis. A list of questions from ISO is included as a checklist with the option of commenting on the entries. Step 4 Final evaluation and report There are warning messages, where applicable, indicating that the required safety level PLr has not been reached and highlighting the critical elements to assist with further investigation. The current state of analysis in respect of all safety functions can be viewed in the SRP/CS event tab throughout the modelling process.

10 The final report contains all the information required for archiving. The detail, layout and language can be adapted as required. Step 5 The next project The system saves time because entirely new configurations are rare and much of the data can be used again in the next project.

11 PAScal Safety Calculator PAScal Calculation software for the verification of functional safety Easy drag-&-drop operation No knowledge of mathematical context required Search functions Import and export components from manufacturers libraries (Sistema, Excel and PAScal format) Six languages Calculations certified by TÜV-Süd inspectorate Updates available at: Webcode 6494

12 Your projects belong in safe hands , Printed in Germany Pilz GmbH & Co. KG, 2011 As a full-service supplier of control and safety technology, Pilz can offer worldwide support and help you to develop and adopt the right safety strategy for your situation. Our services encompass the entire machine life cycle. Consulting and engineering With over 30 years of experience in the safety sector, we are a reliable provider of services for national and international industrial enterprises. We offer viable solutions to the most complex safety issues, helping companies to apply and adapt manufacturing processes with a view to optimising the availability and productivity of their facilities all over the world. Our services are approved by various national and international committees and are available worldwide with the same quality and implementation of service. 24-hour hotline Pilz operates a 24-hour hotline for technical support. This service is provided free of charge outside standard business hours and in the relevant language: Tel.: support@pilz.com Internet: Webcode 3408 Pilz GmbH & Co. KG Felix-Wankel-Straße Ostfildern, Germany Tel.: Fax: pilz.gmbh@pilz.de Internet: InduraNET p, Pilz, PIT, PMCprotego, PMI, PNOZ, Primo, PSEN, PSS, PVIS, SafetyBUS p, SafetyEYE, SafetyNET p, the spirit of safety are registered and protected trademarks of Pilz GmbH & Co. KG in some countries. We would point out that product features may vary from the details stated in this document, depending on the status at the time of publication and the scope of the equipment. We accept no responsibility for the validity, accuracy and entirety of the text and graphics presented in this document. Please contact our Technical Support staff if you would like any further information.