A thermal cutoff at least includes a current-carrying fusible element having two ends connected to a first electrode and a second electrode. The current-carrying fusible element is provided in a closed cavity bounded by a housing having an opening at one end, a cover plate, and a sealant. The thermal cutoff further includes a first lead wire and a second lead wire each wrapped by an insulating sheath. One end of the first lead wire and one end of the second lead wire are electrically connected to the first electrode and the second electrode. The sealant is filled in the opening of the housing, covers an electrical joint between the first lead wire and a first electrode plate and an end of the first lead wire, and also covers an electrical joint between a second electrode plate and the second lead wire and an end of the second lead wire.

An arc flash mitigation system includes a main circuit protector such as a high amperage overcurrent protection fuse, and an arc flash mitigation network connected in parallel to the main circuit protector. The arc flash mitigation network includes at least one semiconductor switch operable to provide a shunt current path to a low amperage arc mitigation fuse for a faster response time to certain circuit conditions than the main circuit protector otherwise provides. The semiconductor switch may be a silicon controller rectifier operatively responsive to a voltage drop across the main circuit protector in use.

An arc flash mitigation system includes a main circuit protector such as a high amperage overcurrent protection fuse, and an arc flash mitigation network connected in parallel to the main circuit protector. The arc flash mitigation network includes at least one semiconductor switch operable to provide a shunt current path to a low amperage arc mitigation fuse for a faster response time to certain circuit conditions than the main circuit protector otherwise provides. The semiconductor switch may be a silicon controller rectifier operatively responsive to a voltage drop across the main circuit protector in use.

Provided are approaches for forming a fusible element assembly, wherein an arc suppressant (e.g., silicone) is deposited on a fusible element. The arc suppressant is delivered to the fusible element at a plurality of angles.

A mechanical breaking and fusing combined multi-fracture excitation fuse includes a shell, wherein a cavity is formed in the shell, and at least one conductor penetrates through the shell and penetrates through the cavity; at least one excitation device and one breaking device are arranged in the cavity of the shell; the excitation device can receive an external excitation signal to drive the breaking device to act to break a conductor corresponding thereof to form at least two fractures on the conductor, at least one fuse is connected in parallel onto the conductor. The melt is connected in parallel with at least one fracture, and the melt is connected in series with at least one fracture.

A mechanical breaking and fusing combined multi-fracture excitation fuse includes a shell, wherein a cavity is formed in the shell, and at least one conductor penetrates through the shell and penetrates through the cavity; at least one excitation device and one breaking device are arranged in the cavity of the shell; the excitation device can receive an external excitation signal to drive the breaking device to act to break a conductor corresponding thereof to form at least two fractures on the conductor, at least one fuse is connected in parallel onto the conductor. The melt is connected in parallel with at least one fracture, and the melt is connected in series with at least one fracture.

A protective element includes: a fuse element cuttable by energization in a first direction; a slider made of an insulating material, including: a plate-shaped portion extending in the first direction; a shielding portion erected in a second direction on the plate-shaped portion, having a shielding-portion through hole penetrating the shielding portion; and a case made of an insulating material, including a housing portion which houses a slider and a portion of the fuse element. The housing portion includes: a shielding-portion housing space which houses the shielding portion such that the shielding portion is movable in the second direction; and a plate-shaped-portion moving space which houses the plate-shaped portion such that the plate-shaped portion is movable in the second direction Prior to the fuse element being cut, the slider and the fuse element are housed such that the fuse element is inserted into the shielding-portion through hole.

An arc flash mitigation system includes a main circuit protector such as a high amperage overcurrent protection fuse, and an arc flash mitigation network connected in parallel to the main circuit protector. The arc flash mitigation network includes at least one semiconductor switch operable to provide a shunt current path to a low amperage arc mitigation fuse for a faster response time to certain circuit conditions than the main circuit protector otherwise provides. The semiconductor switch may be a silicon controller rectifier operatively responsive to a voltage drop across the main circuit protector in use.

An arc flash mitigation system includes a main circuit protector such as a high amperage overcurrent protection fuse, and an arc flash mitigation network connected in parallel to the main circuit protector. The arc flash mitigation network includes at least one semiconductor switch operable to provide a shunt current path to a low amperage arc mitigation fuse for a faster response time to certain circuit conditions than the main circuit protector otherwise provides. The semiconductor switch may be a silicon controller rectifier operatively responsive to a voltage drop across the main circuit protector in use.

A fuse including a fuse body having a base with a central portion and first and second sidewalls, the central portion having first and second fastening holes formed therethrough, a mid-body disposed atop the central portion and having first and second troughs formed in a top surface thereof and separated by a partition wall, the mid-body further having first and second through holes formed therethrough, and a cover disposed atop the mid-body and having a central portion and first and second sidewalls, the central portion having first and second fastening bosses extending therefrom and through the first and second through holes of the mid-body and the first and second fastening holes of the base, and a conductive portion including first and second terminal portions connected by parallel first and second fuse members disposed within the first and second troughs of the mid-body and separated by the partition wall.