In this thesis, we examined the influence of ambient temperature on the tripping characteristics of a residual current circuit breaker with overcurrent protection (RCCB). The tripping characteristic is ensured by a bimetallic disc that bends at approximately 127.5 °C, causing the switch to trip and interrupt the current. Since the tripping characteristic is calibrated at 30 °C, changes in ambient temperature significantly affect the switch's performance. A review of relevant literature laid the groundwork for the experimental work, in which we measured the temperatures of current-carrying components using a thermal imaging camera and thermocouples. These measurements served as reference data for developing a thermodynamic numerical model. Using this model, we calculated tripping currents at different ambient temperatures and compared these results with experimentally determined tripping currents. Finally, we calculated correction factors and adjusted nominal currents based on ambient temperature.
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