Thermal-magnetic circuit breakers combine the benefits of a thermal and magnetic circuit breakers all in one package: a delay that avoids nuisance tripping caused by normal inrush current and fast response at high currents. High overcurrents cause the solenoid to trigger the release machanism rapidly, while the thermal mechanism responds to prolonged low value overloads. They have a characteristic two-step trip profile that provides fast short-circuit protection of expensive electrical systems while minimizing the risk of disrupted system operations.