Family circuits, office building area circuits, etc. 20A fixed rating with fuse box switch can be used for ordinary residential, commercial buildings and industrial equipment and other places of circuit protection and control devices. For example, household circuits, office building area circuits, shopping malls and supermarkets circuits, machining and manufacturing circuits, etc. 20A fixed with fuse box switch is an electrical component, mainly used in AC50HZ or 60HZ, rated voltage does not exceed 380V, rated current does not exceed 20A circuit, as the line of protection and control devices.