This thesis presents safety problems in industrial plants, and standards (IEC 61508, IEC61511) that address safety issues. In addition the steps to improve safety by using safety systems (SIS) according to standards in this area are introduced.
In the context of these steps special attention is focused on risk analysis, and selection and implementation of fail-safe systems. This is followed by an overview of the most common fail-safe controllers and their comparison with standard controllers. Three practical examples are introduced:
1. emergency shutdown systems (ESD) of the plant in the process industry (production of peroxide). Safety functions are »programmed« with wired system (SIL 4)
2. the use of programmable safety relay »Reer« that is built on woodworking machine
3. description of Siemens S7-315F safety controller that is responsible for furnace cooling
The second and third example also include the description of their programming environments ReeR Mosaic and Step 7. Each individual example is followed by a basic explanation of its parameters and programming presentation.
Thesis concludes with the description of positive and negative experiences during the implementation of the three projects (examples) that are presented in the thesis. The conclusion also points out some of the problems that engineers are facing with when working on safety-critical projects.
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