At Masters Electronic you will find a large choice of Circuit Protection to fill your Bill Of Material (BOM). Enjoy our Circuit Protection Manufacturer Catalog, Price, Datasheet, Specifications, 2D & 3D CAD, Footprint allowing you to build your Electronic & Electrical projects. A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk of fire. Unlike a fuse, which operates once and then must be replaced, a circuit breaker can be reset (either manually or automatically) to resume normal operation.