This thesis addresses electromagnetic compatibility (EMC) from the perspective of safety functions (so-called EMC Safety) in electrical appliances, in accordance with the requirements of standards IEC 60335 and IEC 62841. The focus is on assessing the reliability of safety functions when devices operate under elevated levels of electromagnetic disturbances. Through practical testing on two types of devices – an oven and an angle grinder – I examined whether the safety functions still operate correctly even at disturbance levels 30% higher than those defined by the standards.
The test results showed that in most cases, the safety circuits are designed robustly enough and remained functional even under extended test conditions. However, auxiliary components such as displays proved to be more sensitive. One particularly notable case involved an angle grinder, where the safety function failed during a surge immunity test.
Based on the findings, it is recommended that manufacturers verify the performance of safety functions under a broader range of electromagnetic disturbances and under above-standard test conditions, where technically feasible.
The initial part of the thesis presents the basic concepts of electromagnetic compatibility, as well as the relevant requirements of directives and standards governing the verification of safety function performance. This is followed by a description of electromagnetic phenomena that can affect safety-related electronics, along with examples of protection strategies implemented in actual products. The main section of the thesis details the applied test methods and the measurement results obtained from representative samples. The final part provides an analysis of the results, practical solution proposals, and recommendations for improvements in product development.
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