The invention relates to an electric arc-blast nozzle for a circuit breaker comprising a middle portion forming a throat defining internally an axial passage for interrupting an electric arc, and two end portions extending on either side of the middle portion and being designed to receive respective arcing contacts and that are movable axially relative to each other. The middle portion and the two end portions are made of a same dielectric material obtained from a composition consisting of a fluorocarbon polymer matrix and of at least one oxide, the oxide(s) being present in a proportion by weight lying in the range 11% to 50%, relative to the total weight of the composition. The invention also relates to a circuit breaker including such a nozzle.

This application provides azeotropic and near-azeotropic compositions of Z-1233zd and a second component selected from the group consisting of methyl formate, dimethoxymethane, HFC-43-10-mee and HFC-245fa. The inventive compositions are useful as aerosol propellants, refrigerants, cleaning agents, expansion agents for thermoplastic and thermoset foams, solvents, heat transfer media, gaseous dielectrics, fire extinguishing and suppression agents, power cycle working fluids, polymerization media, particulate removal fluids, carrier fluids, buffing abrasive agents, and displacement drying agents. The compositions were modeled based on Vapor-Liquid Equilibria data such as those illustrated in the figures.

The present application relates to an apparatus for the generation, transmission, distribution and/or usage of electrical energy, the apparatus including a housing enclosing an insulation space and an electrically conductive part arranged in the insulation space, wherein the insulating space contains a dielectric fluid including carbon dioxide and oxygen. In the apparatus an oxidation catalyst is arranged that includes noble metal particles coated onto or embedded into a carrier and serves for the catalytic oxidation of carbon monoxide to carbon dioxide.

The present application relates to an apparatus for the generation, transmission, distribution and/or usage of electrical energy, the apparatus including a housing enclosing an insulation space and an electrically conductive part arranged in the insulation space, wherein the insulating space contains a dielectric fluid including carbon dioxide and oxygen. In the apparatus an oxidation catalyst is arranged that includes noble metal particles coated onto or embedded into a carrier and serves for the catalytic oxidation of carbon monoxide to carbon dioxide.

The present invention relates to the use of a linear octafluorobutene as a dielectric compound in an environmentally safe dielectric-insulation or arc-extinction fluid for an apparatus for the generation, the transmission, the distribution and/or the usage of electrical energy.

The present invention relates to the use of a linear octafluorobutene as a dielectric compound in an environmentally safe dielectric-insulation or arc-extinction fluid for an apparatus for the generation, the transmission, the distribution and/or the usage of electrical energy.

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 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.

The present invention relates to an electrical insulation system having a low environmental impact comprising two fundamental elements: a) a gaseous medium formed by one or more highly fluorinated fluoroketones having between 4 and 12 carbons, at least another additional dielectric gas, other than the fluoroketones, with a vapor pressure greater than 500 mbar and less than 15000 mbar at 0 C., such as fluoronitrile (CF.sub.3).sub.2CFCN, for example, and one or more vector gases; and b) a molecular sieve capable of discriminating water molecules from molecules of other gases present in the gaseous medium of the system. The invention also relates to the use of the insulation system and to the medium- or high-voltage electrical switchgear comprising a complete enclosure in which there are arranged live electrical components and an electrical insulation system according to the invention.

An apparatus for heating an insulation fluid in a medium-voltage or high-voltage switchgear comprises an infrared source which is adapted to emit infrared radiation of at least one wavelength. Thus, at least one vibrational or rotational mode of at least one component of the insulation fluid is excited by absorption of at least a part of the infrared radiation, and condensation of the insulation fluid is efficiently prevented by this direct heating of the insulation fluid. A closed loop temperature regulator is used to heat only when required. A circulator in a heating chamber further provides for a mixing of the insulation fluid, thus preventing steep temperature gradients.