Abstract: The invention relates to a high tension circuit breaker capable of interrupting alternating fault currents which have a pseudo period T. The faults occur at an instant t.sub.0 and delay the zero crossing of the current after a maximum time lapse of t.sub.zmax -t.sub.0. The circuit breaker includes a plurality of interrupting chambers in series. These chambers open at an instant t.sub.1 which is subsequent to the fault instant t.sub.0 and include moving equipment and an arc blaster. The arc blaster operates between instant t.sub.1 and instant t.sub.c, where instant t.sub.c is earlier than the instant t.sub.zmax -T. The circuit breaker also includes a feature which causes blasting to be extended to an instant t.sub.2 lying in the range t.sub.zmax -T and t.sub.zmax +T.

Abstract: A three-phase electrical power line comprising a sealed tubular envelope of steel filled with insulating gas under pressure, e.g. nitrogen or carbon dioxide CO.sub.2, and having three conductive bars placed therein together with a thin tubular envelope of aluminum which is located between the steel envelope and the bars, wherein the conductive bars are held by collars made of non-magnetic material, having an outside diameter equal to the inside diameter of the aluminum tubular envelope, and possessing three radial arms which are screwed to tabs of insulating supports that enclose the conductive bars.

Abstract: A Rogowski coil is used as a precise current and temperature measuring device (in particular a device that is highly insensitive to temperature variations). The Rogowski coil is of the type including at least one printed circuit plate provided with a circular cutout. The coil is implemented by metal deposits on each of the two faces of the plate and extending along radii such that geometrical projections thereof pass through the center of the cutout. Electrical connections between the radii on one face and those on the opposite face are implemented by plated-through holes that pass through the thickness of the plate.

Abstract: A capacitor having high stability with temperature comprising a cylindrical metal body, a cylindrical high tension electrode coaxial with the body and placed inside it, and at least two low tension electrodes constrained to remain in contact against the inside wall of the body via an intervening insulating layer, said electrodes being disposed symmetrically about the geometrical axis of the body, said low tension electrodes being held in place by retaining means that allow them to expand freely, the dielectric medium extending between the high tension electrode and the low tension electrodes being a gas or a vacuum, the expansion coefficient .alpha.c of the body being equal to the expansion coefficient .alpha.h of the high tension electrode, and the expansion coefficient .alpha.c of the body material being related to the expansion coefficient .alpha.b of the material of the low tension electrodes by the following inequalities:1.5<.alpha.b/.alpha.c<2.

Abstract: The present invention relates to an apparatus and a method for measuring the current in a high voltage overhead line (A). The apparatus comprises at least one device (2) for detecting and measuring the magnetic field induced by the line (A), the detector being arranged on the ground adjacent the line (A), the current being deduced by calculation.

Abstract: A metal-clad modular power-supply station comprising a main set of busbars interconnecting at least two pairs of components, such as overhead feedthroughs or cable boxes, in an H-station configuration. The components are connected together in pairs by respective rectilinear groups of metal-clad electrical apparatuses that are parallel to and connected to the main set of busbars. Preferably, the groups of electrical apparatuses are in alignment. The length of the set of busbars is thus reduced while complying with the laid-down isolation distances and a station is provided of minimum size and of reduced cost.

Abstract: A circuit-breaker includes first and second permanent contacts, a support tube for a mobile arc contact and a blast nozzle. At least one of these components is fixed via an interference fit. The blast nozzle abuts against one end of a tubular support member with an annular end flange. It bears at the opposite end against a first permanent contact end-piece which is fixed by a clamping ring to the annular flange of the support member.

Abstract: A Rogowski coil comprising at least one printed circuit plate provided with a circular cutout, the coil being implemented by rectilinear metal deposits on each of the two faces of the plate and extending along radii such that geometrical projections thereof intersect in the center of said cutout, electrical connections between the radii on one face and those on the opposite face being implemented by plated through holes that pass through the thickness of the plate.

Abstract: A local network including no more than eight stations, each station being able to be both a source and a sink for data, and, thus being able both to receive and emit a message, the stations being interconnected by a serial bus and providing data to a distributed data base, which data is renewed cyclically under the control of a request generator that emits requests in the form of binary messages. The stations have addresses in the form of bytes respectively constituted by bytes of binary numbers representing powers of 2 in the range 0 to 7, a binary message emitted by the request generator containing the addresses, of all the stations designated to be sinks for the emitted binary message, in the form of a composite byte constituted by an OR UNION of the addresses of the stations designated to be sinks, a station thus observing that it is chosen as a sink by performing an AND INTERSECTION between the composite byte and the station's own address byte.

Abstract: The present invention relates to a superconductive coil assembly which may be used particularly for a current limiter, the coil assembly comprising a plurality of coaxial cylindrical coils electrically connected in series, each coil comprising two windings of superconductive material electrically connected in parallel, arranged coaxially and wound in opposite directions, wherein in each coil, the windings are separated by a material which has a surface resistance in the radial direction lying in the range 10.sup.-5 .OMEGA..m.sup.2 to 10.sup.-2 .OMEGA..m.sup.2 at the temperature of the cryostat, and in which the strands which constitute the superconductive wires may themselves be covered with a layer of the same material.

Abstract: Control and self-monitoring system for an electrical apparatus comprising three poles, each including a closing coil and an opening coil, an opened auxiliary contact, and a closed auxiliary contact, wherein each of the poles is provided with a microprocessor receiving, in particular, information from the opened auxiliary contacts and controlling two static relays in series respectively with the circuit of the opening coil and in the circuit of the closing coil, the microprocessors being subscribers to a local bus comprising a serial bus under the control of a management member and connected to a processor station receiving the signals collected by the microprocessors and the signals issued by the protection devices or by the operator.

Abstract: A puffer circuit-breaker comprises a first interrupting chamber (2), a second interrupting chamber (4) situated within the first interrupting chamber, and a stationary electric arcing contact (6) which extends inside the second interrupting chamber. The second interrupting chamber is movably mounted in the first interrupting chamber and is arranged to slide along the stationary contact. This arrangement provides good arc-extinction both at low electric current and at high electric current.

Abstract: The present invention relates to an electrical contact system, in particular for a circuit-breaker, for establishing electrical contact between the respective ends of two conductive tubes (1) and (3) by fitting them together so that the end of one tube is inserted into the end of the other tube. According to the invention, one of the tubes (1), (3) includes a cavity (4) at its end, the cavity having an opening facing the other tube (3), (1) over at least a portion of the periphery of the tube, and a conductive component (2) is held in said cavity (4) which component is in part deformable radially relative to the tube, the conductive component coming into contact with the bottom of the cavity, and projecting out from the opening in the cavity.

Abstract: An inertia contact designed to co-operate with a contact in series with a component, such as a resistor or a varistor, is disposed in the interrupting chamber of a circuit-breaker so as to be inserted in parallel with the contacts of the circuit-breaker for a limited period of time. The circuit-breaker includes a tube supporting moving contacts and connected to a drive rod. The inertia contact comprises a circularly-symmetrical metal casing coaxial with the tube and surrounding the tube. The casing is substantially tubular in shape with a projection flanked by two rings fitting snugly and slidably against the tube. A first end of the inertia contact is made of an alloy that is resistant to the effects of arcing. A second end of the inertia contact serves to fix the inertia contact to a first end of at least one spring. A second end of the spring is fixed to the tube.