# US 2014/0190726 A1 · Mixture of decafluoro-2-methylbutan-3-one and a carrier gas as a medium for electrical insulation and/or for electric arc extinction in medium-voltage > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190726 A1 - Document ID: US20140190726A1 - Status: Published application - Kind: A1 - Application number: 14/119,352 - Filed: 2012-05-24 - Published: 2014-07-10 - Earliest claimed: 2011-05-24 - Assignees: Schneider Electric Industries SAS - Inventors: Yannick Kieffel; Alain Girodet; Daniel Piccoz - Web page: https://patentgrep.com/patent/US20140190726A1 ## CPC - H01B 3/56: gases - H01H 33/22: Selection of fluids for arc-extinguishing - H02B 13/055: Features relating to the gas - H01H 2033/566: {Avoiding the use of SF6} - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - H02B: BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER ## Abstract The invention relates to the use of a mixture comprising decafluoro-2-methylbutan-3-one and a carrier gas or dilution gas as a medium for electrical insulation and/or for extinction of electric arcs in a medium- or high-voltage electrical device. It also relates to a medium- or high-voltage electrical device in which electrical insulation and/or extinction of electric arcs is/are implemented by a mixture comprising decafluoro-2-methylbutan-3-one and a carrier gas or dilution gas. Applications: electrical transformers, gas-insulated lines for transporting or distributing electricity, set of busbars, electrical connection/disconnection devices (circuit breakers, switches, switch-fuse sets, disconnectors, earthing switches, contactors, etc.). ## Claims ### Claim 1 A process, comprising mixing a fluoroketone with a carrier gas to form a mixture which is suitable as an electrical insulation medium and/or a medium for extinction of electric arcs in a medium-voltage electrical device, wherein: the fluoroketone is decafluoro-2-methylbutan-3-one and is present in the mixture in a molar percentage at least equal to 95% of a molar percentage M determined by formula (I): M=(PC5K/Pmixture)×100 (1); where: Pmixture represents a pressure, expressed in kilopascals, of the mixture at 20° C. in the electrical device; PC5K represents a pressure, expressed in kilopascals, which is equivalent at 20° C. to a saturation vapor pressure of the decafluoro-2-methylbutan-3-one at a minimum service temperature of the electrical device, where PC5K is determined by formula (II): PC5K=(PVSC5K×293)/Tminimum PVSC5K represents the saturation vapor pressure of the decafluoro-2-methylbutan-3-one at the minimum service temperature of the electrical device, expressed in kilopascals; and Tminimum represents the minimum service temperature of the electrical device, expressed in Kelvin. ### Claim 2 (depends on 1) The process according to claim 1, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage is between 95% and 130% of the molar percentage M. ### Claim 3 (depends on 2) The process according to claim 2, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage between 99% and 110% of the molar percentage M. ### Claim 4 (depends on 1) The process according to claim 1, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage between 95% and 100% of the molar percentage M. ### Claim 5 (depends on 1) The process according to claim 1, wherein the carrier gas is selected from the group consisting of air, nitrogen, nitrous oxide, carbon dioxide, a mixture of carbon dioxide and oxygen in a volume ratio of between 90/10 and 97/3, and a mixture of these gases. ### Claim 6 A medium-voltage electrical device, comprising a sealed enclosure comprising electrical components and a mixture comprising a fluoroketone and a carrier gas for electrical insulation and/or extinction of the electric arcs which are produced within this device, wherein: the fluoroketone is decafluoro-2-methylbutan-3-one and is present in the mixture in a molar percentage at least equal to 95% of a molar percentage M determined by the formula (I): M=(PC5K/Pmixture)×100 (I); Pmixture represents a pressure, expressed in kilopascals, of the mixture at 20° C. in the electrical device; PC5K represents a pressure, expressed in kilopascals, which is equivalent at 20° C. to a saturation vapor pressure of the decafluoro-2-methylbutan-3-one at a minimum service temperature of the electrical device, where PC5K is determined by formula (II): PC5K=(PVSC5K×293)/Tminimum (II); PVSC5K represents the saturation vapor pressure of the decafluoro-2-methylbutan-3-one at the minimum service temperature of the electrical device, expressed in kilopascals; and Tminimum represents the minimum service temperature of the electrical device, expressed in Kelvin. ### Claim 7 (depends on 6) A device according to claim 6, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage which is between 95% and 130% of the molar percentage M. ### Claim 8 (depends on 7) A device according to claim 7, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage which is between 99% and 110% of the molar percentage M. ### Claim 9 (depends on 6) A device according to claim 6, wherein the decafluoro-2-methylbutan-3-one is present in the mixture in a molar percentage which is between 95% and 100% of the molar percentage M. ### Claim 10 (depends on 6) A device according to claim 6, wherein the carrier gas is selected from the group consisting of air, nitrogen, nitrous oxide, carbon dioxide, a mixture of carbon dioxide and oxygen in a volume ratio of between 90/10 and 97/3, and a mixture of these gases. ### Claim 11 (depends on 6) A device according to claim 6, which is a gas-insulated transformer, a gas-insulated line for transporting or distributing of electricity, or an electrical connection/disconnection device.