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Bimetal Circuit Breaker

A Bimetal Circuit Breaker is a circuit protection device that is appropriate for low voltage applications. The active element of the breaker is a strip of 2 different metals bonded together, known as a bimetal strip. Under normal operation, the strip spans a distance between two contactors, completing the circuit. When the circuit is thermally overloaded, the strip bends as a result of the difference in the linear thermal expansion coefficients between the two metals in the bimetal strip. When this happens, contact is broken and the circuit is open, preventing damage to the circuit.