Abstract: An aliphatic polyamide film or fibrous material is employed for electrical insulation in individual conductors, groups of conductors, magnet wire, magnet wire coils, and layers in liquid filled electrical transformers. The material is stabilized with additives that produce improved moisture resistance, moisture stability, thermal stability, thermal conductivity, reduced insulation thickness, reduced shrinkage, and improved insulation elasticity for the insulation material thereby providing a longer useful life for the material.

Abstract: The present invention is a modular tank coupled to a self-assembly cabinet for ground level transformers. The modular tank includes two interconnected tanks, a front plate and a base. The first tank is larger than the second one and contains the high tension elements. The second tank contains the low tension elements. The front plate supports the electric contacts for both tanks. The base supports the first tank and allows lifting above the ground. The self-assembly cabinet for ground level transformer has a cover divided into two sections. The first section acts as a cover for the modular tank, while the second section acts as a cover for the cabinet. Both cover sections are joined together by a hinge mechanism, and are assembled by sliding on top of the modular tank by a lateral rail mechanism.

Abstract: In one aspect, the present invention provides a dielectric fluid for use in electrical equipment comprising a vegetable oil or vegetable oil blend. In another aspect the invention provides devices for generating and distributing electrical energy that incorporate a dielectric fluid comprising a vegetable oil or vegetable oil blend. Methods of retrofilling electrical equipment with vegetable oil based dielectric fluids also are provided.

Abstract: Disclosed herein are a dielectric fluid composition and a method thereof. Also disclosed are viscosity modifiers and a method of lowering the viscosity of an oil-based dielectric fluid. The composition includes an oil with a high mono-unsaturated fatty acid content and one or more fatty acid alkyl esters, each having a fatty acid and an alkyl moiety, wherein the alkyl moiety of the fatty acid alkyl esters has 1 to 4 carbon atoms, and wherein both the oil and the fatty acid alkyl ester are in the range of 40%-60% v/v of the dielectric fluid composition. The viscosity modifier includes one or more fatty acid alkyl esters with an alkyl moiety and a fatty acid moiety, wherein the alkyl moiety has 1 to 4 carbon atoms. The method of lowering the viscosity includes blending the viscosity modifier and a vegetable oil-based dielectric fluid in a ratio of 40:60-60:40.

Abstract: A high voltage insulation system for high-voltage direct current including a bushing, a conductor, a transformer conductor, and a connection between the conductor and the transformer conductor. A conductive shielding electrode shields the connection between the bushing and transformer. A surrounding insulation system is immersed in transformer oil. The surrounding insulation system includes transformer insulation material and bushing insulation material. A cylindrical solid insulation barrier encloses the connection between the bushing conductor and transformer conductor. At least one solid insulation barrier is fastened on the outer side of the shielding electrode. The at least one solid insulation barrier extends in an axial direction outside the axial direction of the shielding electrode and forms a distance to the insulation material of the bushing and the insulation material of the transformer, whereby a moderate voltage drop over the solid insulation barrier is obtained.

Abstract: A dielectric fluid comprising hydrocarbon liquid admixed with an ester-based compound, wherein the ester-based compound is present in an effective amount to impart breakdown inhibiting properties to a paper insulation material when the dielectric fluid is in contact with the paper material.

Abstract: An arrangement and a method for use in installation procedures for subsea transformers. A central, hole or tube is included in an encapsulation enclosing a transformer that is to be installed. Three core elements of the transformer are arranged symmetrically around the hole or tube forming a triangle or a delta. The transformer is lowered towards a a foundation placed on the sea floor wherein a guide pin is mounted. When the transformer has found its way to the foundation, the guide pin will enter the tube, and the transformer will slide down onto the guide line pin. The tube is terminated by a funnel shaped opening, thus making it easier not to miss the guide pin by the tube opening. The transformer is horizontally oriented by means of orientation keys localized within the tube.

Abstract: In one aspect, the present invention provides a dielectric fluid for use in electrical equipment comprising a vegetable oil or vegetable oil blend. In another aspect the invention provides devices for generating and distributing electrical energy that incorporate a dielectric fluid comprising a vegetable oil or vegetable oil blend. Methods of retrofilling electrical equipment with vegetable oil based dielectric fluids also are provided.

Abstract: An electronic device receives data containing content data transmitted through a bus in the form of a packet. The electronic equipment has a receiving portion, a judgment portion and an output controller. The receiving portion receives the data transmitted in the form of a packet through the bus. The judgment portion extracts copyright information from the data supplied from the reception portion, and judges on the basis of the copyright information thus extracted whether the content data contained in the data received are allowed to be copied. The output controller is supplied with the judgment result from the judgment portion to generate notification data corresponding to the judgment result.

Abstract: A three-phase transformer is presented comprising a magnetic circuit and three coil block. The magnetic circuit comprises two spaced-apart, parallel, plate-like elements; and three spaced-apart, parallel column-like elementary circuits. Each of the column-like elementary circuits carries the corresponding one of the three coil blocks, and serves for the corresponding one of the three phases. The column-like elementary circuits are substantially perpendicular to the plate-like elements, and are enclosed therebetween such as to form a spatial symmetrical structure about a central axis of the transformer.

Abstract: A sound-insulating device for a stationary induction machine with an active part, an insulating fluid surrounding the active part, and a tank enclosing the insulating fluid. The sound-absorbing device includes a gas-filled cavity and a resilient member surrounding the gas-filled cavity, thus obtaining a sound-insulating device that is extremely compressible. In the induction machine, the device is arranged between the active part and the tank of the induction machine and is spaced from the inside of the tank. The sound-insulating device preferably has an extent in one plane, whereby the device has a membrane portion facing the active part and a membrane portion facing the tank. Preferably, at least one of the membrane portions has at least one corrugated region, and a spacing membrane is arranged in the cavity making contact with the membrane portion at at least two points.

Abstract: In one aspect, the present invention provides a dielectric fluid for use in electrical equipment comprising a vegetable oil or vegetable oil blend. In another aspect the invention provides devices for generating and distributing electrical energy that incorporate a dielectric fluid comprising a vegetable oil or vegetable oil blend. Methods of retrofilling electrical equipment with vegetable oil based dielectric fluids also are provided.

Abstract: A non-contact transformer includes a transformer component provided on the floor of a housing, a printed circuit board on the transformer component, and an empty core space is formed within the transformer component wherein deformation of the housing is prevented through a construction that evacuates residual air from the core space when the core space is filled with resin even though both ends of the core space are covered by lid-like parts. A cylindrical end face at one extremity of the primary transformer component is positioned on the bottom plate of the primary housing opposed to the secondary housing, and the printed circuit board is provided on an opposite cylindrical end face which is at the other extremity of the primary transformer component. A passage is formed between the printed circuit board and the primary transformer component to provide a connecting orifice between a core space of primary transformer component and the space external to the primary transformer component.

Abstract: The present invention comprises a mixture of hydrocarbons having a well-defined chemical composition that is suitable for use as a dielectric coolant in electrical equipment in general, and specifically in transformers. The dielectric coolants of the present invention are particularly suited for use in sealed, non-vented transformers, and have improved performance characteristics, including decreased degradation of the paper insulating layers, as well as a greater degree of safety and environmental acceptability. The present dielectric coolants comprise relatively pure blends of compounds selected from the group consisting of aromatic hydrocarbons, polyalphaolefins, polyol esters, and natural vegetable oils, along with additives to improve pour point, increase stability and reduce oxidation rate.

Abstract: A container (2) with an oil immersed core (1) and windings has corrugated walls. Bushing insulators (9,10) have pressure-resistant and water-resistant cable shoes (11). A tank encompasses another container (4) filled with insulating oil (3) and has pressure-resistant cable bushing (13) and connectors for electrical connections of the transformer.

Abstract: In one aspect, the present invention provides a dielectric fluid for use in electrical equipment comprising a vegetable oil or vegetable oil blend. In another aspect the invention provides devices for generating and distributing electrical energy that incorporate a dielectric fluid comprising a vegetable oil or vegetable oil blend. Methods of retrofilling electrical equipment with vegetable oil based dielectric fluids also are provided.

Abstract: A dielectric fluid system for use in electrical equipment comprising a dielectric fluid comprising vegetable oil and an oxidation reducing composition encased in a housing composed of a polymeric material that is substantially permeable to oxygen. The oxidation reducing composition is placed inside the electrical equipment such that it is in contact with a headspace defined by the dielectric fluid. Devices generating and distributing electrical energy incorporating the above-described dielectric fluid system and method of retrofilling such devices also are provided.

Abstract: High oleic acid triglyceride compositions that comprise fatty acid components of at least 75% oleic acid, less than 10% diunsaturated fatty acid component; less than 3% triunsaturated fatty acid component; and less than 8% saturated fatty acid component; and having the properties of a dielectric strength of at least 35 KV/100 mil gap, a dissipation factor of less than 0.05% at 25° C., acidity of less than 0.03 mg KOH/g, electrical conductivity of less than 1 pS/m at 25° C., a flash point of at least 250° C. and a pour point of at least —15° C. are disclosed. Electrical insulation fluids comprising the triglyceride composition are disclosed. Electrical insulation fluids that comprise the triglyceride composition and a combination of additives are disclosed. Electrical apparatuses comprising the electrical insulation fluids and the use of electrical insulation fluids to provide insulation in electrical apparatuses are disclosed.

Abstract: A transformer is disclosed, including a tank housing a transformer core/coil assembly, a dielectric insulating fluid surrounding the core/coil assembly, the fluid comprising a vegetable oil, an antioxidant dissolved in the oil, and a low temperature additive blended into the oil, wherein the fluid defines a headspace above the fluid. The preferred embodiment includes an oxygen absorbing material contained in the tank and in contact with gases in the tank but isolated from contact with the dielectric fluid, the tank including an opening and a sealed plug in the opening, such that the oxygen absorbing material can be replaced through the opening upon removal of the sealed plug, and further includes a gas permeable polymer container sealed against the opening for supporting the oxygen absorbing material and an indicator in gas contact with the headspace and visible from outside the tank for indicating the presence of oxygen in the headspace.

Abstract: An ignition coil assembly module (40) that can be connected to and disconnected from an engine spark plug. The module elements are arranged as a succession of cylindrical layers about a central ferromagnetic core (46). From innermost to outermost, the succession is: a) a secondary bobbin (48), b) a secondary coil (58), c) a secondary encapsulant (194) encapsulating the secondary coil, d) a primary bobbin (50), e) a primary coil (56), f) an inner wall (181) of an environmental shield (42) encapsulating the primary coil, g) a ferromagnetic shell (52), and h) an outer wall (180) of the environmental shield encapsulating the shell. The primary bobbin forms a liquid container for holding secondary coil encapsulant. A terminal (100) extends through a transverse wall (71) of the primary bobbin for carrying secondary current from the secondary coil to another terminal (118) on the other side of the transverse wall that connects to a spark plug (80).

Abstract: A transformer is disclosed, including a tank housing a transformer core/coil assembly, a dielectric insulating fluid surrounding the core/coil assembly, the fluid comprising a vegetable oil, an antioxidant dissolved in the oil, and a low temperature additive blended into the oil, wherein the fluid defines a headspace above the fluid. The preferred embodiment includes an oxygen absorbing material contained in the tank and in contact with gases in the tank but isolated from contact with the dielectric fluid, the tank including an opening and a sealed plug in the opening, such that the oxygen absorbing material can be replaced through the opening upon removal of the sealed plug, and further includes a gas permeable polymer container sealed against the opening for supporting the oxygen absorbing material and an indicator in gas contact with the headspace and visible from outside the tank for indicating the presence of oxygen in the headspace.

Abstract: A food grade, biodegradable dielectric composition and method for preparation thereof, comprising an unsaturated hydrocarbon alone, or in a blend with a food grade natural or synthetic hydrocarbon, which has been processed to remove polar contaminants and further including an antioxidant additive is disclosed.

Abstract: To provide an ignition coil for an internal combustion engine which improves high-voltage sealing performance and moreover reduces housing outer diameter, an ignition coil for an internal combustion engine is made up of a transformer portion of cylindrical configuration housed within a housing chamber of a case, a control-circuit portion which is positioned on one end portion of this transformer portion and causes primary current of the transformer portion to be intermittent, and a connecting portion which is positioned on another end portion of the transformer portion and supplies secondary voltage of the transformer portion to a spark plug. The interior of the housing chamber is filled with insulating oil which has a flash point of 180.degree. C. or more, a total acid number of oxidation stability of 0.6 mgKOH/g or less, a pour point of -20.degree. C. or less with no cloudiness occurring before that temperature is reached, and a kinematic viscosity of not less than 20 cSt and not more than 180 cSt at 40.

Abstract: An electrical apparatus, such as a transformer, includes an expandable internal chamber that is nonventing and completely and permanently sealed from the ambient environment. The chamber houses a core and coil assembly or other current-carrying conductor and is completely filled with dielectric fluid having a pressure less than one atmosphere. The enclosure walls are flexible and are permitted to bow inwardly and outwardly as the volume of the dielectric fluid changes due to thermal expansion and contraction. A method of processing the dielectric fluid and filling and sealing the transformer at sub-atmospheric pressure is also disclosed.

Abstract: A device to capture, contain and collect hydrocarbon fuels such as gasoline and diesel before they can be spilled or leaked from the ventilation valve or fuel intake port of the fuel tank of a vessel and on to the surface of the water during fueling operations at marine fueling facilities. The device is formed as a low-profile box with a floor section and upright wall sections having stratified layers of a textile material and a solidifying polymer enclosed within a outer envelope of textile material. A seamed area at the center of the device with slits in the textile material allows the device to circumscribe the annular conduit of a device passing through the seamed area. The device is positioned to surround the external ventilation valve of the fuel tank of the vessel. Excess fuel that is expelled through the ventilation valve when the capacity of the fuel tank is reached during the fueling operation is captured and absorbed by the device.

Abstract: Novel dielectric liquids for such electrical components as transformers, capacitors and cables, especially adopted for low temperature applications, comprise a mixture of benzyltoluene and (methylbenzyl)xylene isomers, notably a mixture of benzyltoluene/dibenzyltoluene isomers with (methylbenzyl)xylene/di(methylbenzyl)xylene isomers.

Abstract: A convection-cooled electromagnetic device, such as a transformer, and methods of cooling that utilize a ferrofluid as a cooling medium. The device's leakage magnetic field, which can be augmented by auxiliary magnets, draws the ferrofluid toward the device. As the fluid approaches the device its temperature rises, resulting in loss of magnetic properties and a decrease in density. The ferrofluid rises as its temperature approaches the Curie point, since the gravitational effect of density reduction begins to overcome the weakening magnetic attraction. Movement of hot ferrofluid is strongly assisted by the attraction exerted by the device on cooler, more intensely magnetic ferrofluid, which displaces the hot ferrofluid. The displaced ferrofluid cools as a result of movement from the heat source and through contact with the walls of the housing. Preferably, the Curie temperature of the ferrofluid is close to or slightly higher than the operating temperature of the device.

Abstract: An nonflammable insulating liquid is obtained by adding an emulsifying agent having a volume ratio of 1 to 3% to an insulating liquid containing a fluorocarbon liquid of at least 25% in a volume ratio to cause emulsification. In this liquid mixture, when polyol ester or dimethylcyloxane is used as the insulating liquid, an nonflammable insulating liquid that does not cause pollution or an environmental problem can be obtained. When tricresyl phosphate is used as the insulating liquid, an nonflammable insulating liquid having a dielectric constant close to that of insulating paper can be obtained. A liquid pipe for circulating a fluorocarbon emulsion in a tank is provided outside the tank, and a pump and a stirrer are connected midway along the liquid pipe to constantly stir the fluorocarbon emulsion, thereby preventing it from being separated into two layers. When a radiator is provided to the liquid pipe, the stirring system for the fluorocarbon emulsion can also serve as the cooling system.

Abstract: An insulting-liquid immersed electrical machine comprises an electrical machine, a hermetically sealed tank containing the electrical machine, and insulating liquid arranged between the electrical machine and the tank, wherein the tank includes a deformable member through which gas and liquid cannot pass and whose shape is variable so that a receiving volume capable of receiving the insulating liquid between the tank and the electrical machine is variable. The insulating liquid completely fills the receiving volume in the tank, and a pressurizing arrangement is provided for adjusting the shape of the deformable member so that the pressure of the insulating liquid in the tank is kept at a suitable degree for preventing the insulating liquid from vaporizing.

Abstract: A motor control system includes a single, multicompartment enclosure mounted on a skid. The enclosure contains a transformer circuit and a motor controller circuit interconnected so that only external connections to a power source and a load are heeded. When the circuits are energized, access to high voltage motor control components and to field replaceable fuses and output selection switches is provented by a double interlocking mechanism which operates in conjunction with energizing and de-energizing the transformer. The transformer of the transformer circuit includes a tertiary winding disposed radially between a primary winding and a secondary winding. The winding filters electrostatically coupled transients. A conventional electrostatic shield is also used so that the transformer is doubly shielded to electrostatic transients. The tertiary winding is connected to one or more capacitors to filter magnetically coupled transients.

Abstract: A transformer of the type used to produce high voltage for an electrostatic field apparatus has a hermetically sealed container. The container encloses a coil assembly having primary and secondary coils wound on a common core. Electrical terminals extend outward from the container and are connected to the coils. The interior volume of the container is completely filled with a thermally conductive, electrically non-conducting fluid. The internal pressure of the transformer is less than one atmosphere at 22.degree. C. The transformer can be operated in any mounting orientation of its rated power. A method of manufacturing the transformer is described by which gases are removed from the container so that it can be completely filled with the fluid.

Abstract: An electrical insulating oil composition which comprises 45% by weight or more of at least 2 members selected from the group consisting of (a) m-ethylbiphenyl, (b) p-ethylbiphenyl, (c) o-benzyltoluene, (d) m-benzyltoluene, (e) p-benzyltoluene, and (f) 1,1-diphenylethane; and the remainder of non-condensed bicyclic aromatic hydrocarbons having not more than 17 carbon atoms besides the above 6 components; and is characterized in that, when the temperature of the composition is -40.degree. C., (I) the total quantity of solid phase obtained by calculating according to the following solid-liquid equilibrium equation is 45% by weight or less relative to the total quantity of the composition, and (II) in the liquid phase composition calculated by the following solid-liquid equilibrium equation, the total quantity of the compounds (a) to (f) is 40% by weight or more and the viscosity of this liquid phase is 500 cSt or lower, ##EQU1## wherein X.sub.

Abstract: Novel dielectrically improved liquid compositions include at least one electrical insulating oil (A), e.g., benzyltoluene or oligomers thereof, and at least one aldehyde (B) containing at least six carbon atoms, or a functionally substituted such aldehyde, e.g., 3-ethoxy-4-hydroxybenzaldehyde.

Abstract: The present invention relates to an improved electrical insulating oil composition which has excellent electrical characteristics and is suitable for use in impregnating electrical appliances in which plastic dielectric material is used, and further relates to electrical appliances impregnated with such a composition. The electrical insulating oil composition is produced by bringing a by-product oil fraction mainly containing components having boiling points in the range of 260.degree. to 330.degree. C. (atmospheric pressure basis) into liquid-liquid contact with an organic polar solvent; said by-product oil fraction being formed by alkylating benene or toluene with ethylene in the presence of an alkylation catalyst and then distilling the alkylation product; and said electrical insulating oil composition being characterized in that the ratio of the integrated intensity as chemical shift at 120 to 155 ppm of the spectrum measured by .sup.

Abstract: A gas-insulated stationary induction electrical apparatus comprising a first closed vessel sealingly accommodating therein a main body having an iron core formed by laminating silicon steel sheets and also having at least one set of windings each consisting of a high-voltage winding and a low-voltage winding which are disposed apart from the iron core on both sides thereof, and a liquid medium for effecting cooling and insulation; a second closed vessel formed of an insulating material and sealingly accommodating therein the first closed vessel; and an insulating gas under a predetermined pressure which is sealed within the gap between the first and second vessels, wherein the induction apparatus main body is submerged in the liquid medium.

Abstract: A dielectric medium composition comprising a fluorine-containing amide or a fluorine-containing sulfonamide and capacitors or other electric devices incorporating said composition, are disclosed herein.

Abstract: Described is a transformer wherein the primary winding is formed from the same unitary piece of electrically conductive metal that comprises the housing of the transformer.

Abstract: An apparatus for producing a very high DC potential output from an AC input. Multiple secondary circuits, each comprised of an individual coil wound about a separate magnetic core, are positioned within the magnetic field of a single primary coil. The output of each secondary circuit is rectified. The output of all secondary circuits is combined in series to provide the high DC potential. The seconary cores are supplied in parallel from the magnetic flux of the primary coil. The primary core and coil form an essentially cylindrical shell, with the secondary cores and coils located within the cylinder interior.

Abstract: An electric device particularly adapted for a fire retardant oil-filled transformer, comprising a cellulose-based insulating material impregnated with an insulating oil composed of 100 parts by weight of an ester of a polyol with a fatty acid having a fire point of 300.degree. C. or above and, incorporated therein, 0.005 to 1.0 part by weight of a phenolic compound having no alkyl groups as the substituent at the ortho positions and 0.01 to 2.0 parts by weight of an epoxy compound.

Abstract: A gas insulated current transformer wherein the metal tank having the inductive unit therein is mounted on the hollow insulating bushing and preloaded with spring pressure so that when the insulating gas within the bushing and the container reaches a predetermined and maximum safe limit the excess build up of gas pressure is allowed to escape between the otherwise sealed contact between the container and the bushing.

Abstract: An insulating oil containing N,N-bis(2-hydroxyethyl)-N-cyclohexylamine at 0.5 mg/l or more. An electrical apparatus is filled with the insulating oil in which a copper component is immersed. During operation of the apparatus for a long period of time, the tan .delta. of the insulating oil does not increase so that deterioration of the insulating oil is deferred, thereby substantially extending the life of the insulating oil.

Abstract: Dielectric fluid is prepared by combining perchloroethylene with an aliphatic hydrocarbon having 7-9 carbon atoms in the aliphatic chain. The resulting dielectric has improved freezing point and nonflammability characteristics.

Abstract: An improved electrical insulating oil and oil-filled electrical appliances impregnated therewith. The electrical insulating oil can be produced inexpensively but has excellent electrical characteristics and it comprises a fraction having boiling points in the range of 350.degree. to 450.degree. C. that is prepared by disproportionating diarylalkane or a hydrocarbon mixture mainly containing the same at temperatures in the range of 20.degree. to 500.degree. C. in the presence of a disproportionation catalyst, said diarylalkane having boiling points in the range of 260.degree. to 320.degree. C.

Abstract: Disclosed is a dielectric fluid which comprises about 5 to about 40 molar percent of a first arene compound having up to seven substituent alkenyl carbon atoms and about 60 to about 95 molar percent of a diluent. The diluent can be mineral oil, a second arene compound having up to seven substituent alkyl carbon atoms which are hydrocarbons, hydrocarbon ethers, or a mixture thereof, or a mixture of a mineral oil and a second arene compound. Also preferably included in the dielectric fluid is about 0.5 to about 5% of a free-radical polymerization inhibitor. A capacitor and a transformer containing the dielectric fluid are also disclosed.

Abstract: An electrical insulating oil which is suitable for use in impregnating electrical appliances such as capacitors, cables and transformers, especially those in which plastic materials are used partially or totally as dielectrics or insulating materials, and electrical appliances that are impregnated with the above electrical insulating oil. The electrical insulating oil of the invention contains at least one monoolefin and/or diolefin having three condensed or non-condensed aromatic rings.

Abstract: Dielectric, cooling or arc-extinguishing fluids comprise a mixture of tetrachlorodifluoroethane and perchloroethylene, optionally with incorporation of a third component which is preferably trichlorotrifluoroethane. Transformer and circuit-interrupter apparatus containing such dielectric fluids are also described.

Abstract: A gas-insulated electric device comprising an electric conductor disposed in a sealed vessel filled with an insulating gas, the conductor being supported by a solid insulating member. The insulating gas is a nitrilic fluorocarbon compound or a mixture of a nitrilic fluorocarbon compound and SF.sub.6. In this device, the dielectric strength is increased. Accordingly, the size of the device can be decreased.

Abstract: A flame resistant oil comprising a fluorine-type oil having a number average molecular weight of from about 300 to about 900 and a silicone oil having a number average molecular weight of from about 160 to about 57,000, wherein the fluorine-type oil and the silicone oil are combined and dissolved to each other with a combination of the respective molecular weights selected from the following combinations I to IV:______________________________________ I 300 .ltoreq. X .ltoreq. 900 160 .ltoreq. Y < 400 II 300 .ltoreq. X .ltoreq. 700 + 0.02Z.sup.2 400 .ltoreq. Y < 2,000 III 300 .ltoreq. X .ltoreq. 600 + 0.02Z.sup.2 2,000 .ltoreq. Y < 4,000 IV 300 .ltoreq. X .ltoreq. 500 + 0.02Z.sup.2 4,000 .ltoreq. Y .ltoreq. 57,000 ______________________________________where X is the number average molecular weight of the fluorine-type oil, Y is the number average molecular weight of the silicone oil, and Z is the % by volume of the silicone oil in the flame resistant oil and 10.ltoreq.Z.ltoreq.90.

Abstract: A refined electrical insulating oil and oil-filled electrical appliances impregnated therewith. The electrical insulating oil is quite suitable for use in oil-filled electrical appliances in which insulating materials or dielectric materials made of plastics are employed. The electrical insulating oil is prepared by refining a mixture of unsaturated dimers of styrenes and alkylbiphenyls and/or alkylnaphthalenes, using a solid acidic substance.

Abstract: An insulating gas for an electric device which comprises pentafluoropropionitrile or a mixture of pentafluoropropionitrile and sulfur hexafluoride and at least one nitrite ester selected from methyl nitrite, ethyl nitrite, propyl nitrite, butyl nitrite, and amyl nitrite. The effects of pentafluoropropionitrile on humans can be moderated by addition of the nitrite ester.