Thermal-magnetic circuit breakers contain two different switching mechanisms, a bimetal switch and an electromagnet. The bimetal serves as a means of handling overcurrents. The bimetal typically sits ...

The classic circuit breaker—a resettable overcurrent cutoff device—has been with us since the 1920s and is well-known for its reliable, consistent performance and a simple schematic symbol (Fig. 1).

During normal operation, thermal circuit breakers utilize a thermal sensing element (such as bimetal), which deflects when the temperature reaches a predetermined calibration level, causing the ...

Because of an experience when I worked for GMC Truck and Coach 30 years ago, I have always thought thermal circuit breakers were not very good. Yet a recent experience with a thermal breaker seems to ...