A method of making a fuse including inserting a fuse element into a cavity in a hollow fuse body, attaching a first end cap to the hollow fuse body and electrically connecting a first end of the fuse element to the first end cap, adding a mixture of particles including a melamine compound and a steatite of at least 2 times the melamine compound by weightto the cavity such that the mixture of particles are disposed around the fuse element, and attaching a second end cap to the hollow fuse body and electrically connecting a second end of the fuse element to the second end cap.

A switching device includes an electrode housing having an opening; a first electrode provided inside the electrode housing; and a second electrode that fits in the opening such that the second electrode comes into and out of contact with the first electrode. The electrode housing generates an ablation gas through an arc generated between the first electrode and the second electrode. Until the first electrode and the second electrode become separated by a certain distance, a gas including the ablation gas is retained in an enclosed space defined by the first electrode, the second electrode, and the electrode housing. When a distance by which the first electrode and the second electrode are separated from each other exceeds the certain distance, the gas in the enclosed space is discharged through a gap defined between the opening and the second electrode, such that the gas is blown onto the arc.

A circuit breaker system has an SF6 tank having a wall, and an SF6 heating system. The SF6 heating system includes a heater disposed externally of the tank, and a radiator disposed on the wall inside the SF6 tank. The radiator is thermally coupled to the heater via the wall. The heating system is constructed to conduct heat from the heater through the wall to the radiator. The radiator is constructed to radiate the heat to the SF6 in the tank. A circuit breaker system has an SF6 tank having a wall, and a particle trap. The particle trap has a spar extending radially inward from the wall and a wing extending outward from each side of the spar. Each wing is spaced apart from the wall and forms a region having no electric field at the bottom of the tank adjacent the spar.

A breaker comprises a static contact, a moving contact, and an arc-extinguishing chamber. A contact surface of an electrical contact of the static contact and an electrical contact of the moving contact and a bottom plane of a base form an acute angle that is located in the first quadrant. The moving contact comprises a conducting rod having a projecting portion, and the electrical contact which is welded on an end surface of the projecting portion in a direction facing the electrical contact of the static contact. A bottom arc-ignition grid plate on the bottom of the arc-extinguishing chamber is arranged lower than the electrical contact of the static contact. A top arc-ignition grid plate on the top of the arc-extinguishing chamber is arranged higher than the maximum position of the electrical contact of the moving contact when the moving contact is opened.

Fuses having a melamine-coated-steatite foam filler are described. In particular, melamine-coated-steatite foam filler for use in a fuse comprising steatite coated in a melamine compound (e.g., plasticized melamine resin) and then heated to form crystalline foam filler are described. The foam filler may comprise steatite of substantially 3 times the melamine compound by weight and may be heated and then cooled to form the foam filler.

A circuit breaker system has an SF6 tank having a wall, and an SF6 heating system. The SF6 heating system includes a heater disposed externally of the tank, and a radiator disposed on the wall inside the SF6 tank. The radiator is thermally coupled to the heater via the wall. The heating system is constructed to conduct heat from the heater through the wall to the radiator. The radiator is constructed to radiate the heat to the SF6 in the tank. A circuit breaker system has an SF6 tank having a wall, and a particle trap. The particle trap has a spar extending radially inward from the wall and a wing extending outward from each side of the spar. Each wing is spaced apart from the wall and forms a region having no electric field at the bottom of the tank adjacent the spar.

Fuses having a melamine-coated-steatite foam filler are described. In particular, melamine-coated-steatite foam filler for use in a fuse comprising steatite coated in a melamine compound (e.g., plasticized melamine resin) and then heated to form crystalline foam filler are described. The foam filler may comprise steatite of substantially 3 times the melamine compound by weight and may be heated and then cooled to form the foam filler.

A breaker comprises a static contact, a moving contact, and an arc-extinguishing chamber. A contact surface of an electrical contact of the static contact and an electrical contact of the moving contact and a bottom plane of a base form an acute angle that is located in the first quadrant. The moving contact comprises a conducting rod having a projecting portion, and the electrical contact which is welded on an end surface of the projecting portion in a direction facing the electrical contact of the static contact. A bottom arc-ignition grid plate on the bottom of the arc-extinguishing chamber is arranged lower than the electrical contact of the static contact. A top arc-ignition grid plate on the top of the arc-extinguishing chamber is arranged higher than the maximum position of the electrical contact of the moving contact when the moving contact is opened.