Thermal behavior of automatic Thermal-Magnetic protection circuit-breakers: Experimental test

The paper reports laboratory tests to evaluate the thermal behavior of thermal-magnetic protection circuit-breakers. They are characterized by a rather variable intervention mode according to the environmental and operating thermal conditions. The scope is verify a relationship between the thermal image of the circuit-breaker and the phenomena that lead the actuator mechanism to tripping. The work shows a various types of temperature sensors and location, highlighting their performance, according to these measurement tests. Thanks to the programmable converters, used for the control of industrial processes, a measurement and data processing system has been implemented integrating directly with PLC Arduino, allowing real-time observation of the measurements. The goal is evaluate the influences of external and environmental temperatures, and on the tripping device mechanism.