Abstract: Device for connecting a coaxial cable end to a contact socket A device for connecting a coaxial cable end (2a) which may be provided with a cable end-plug (4) to a contact socket (3) comprises a further socket element (9) surrounding the contact socket (3), a seal (8) positioned between the further socket element (9) and the coaxial cable (2a), and a pressing element (11,12) which can deform the seal into contact with the coaxial cable (2a) and the further contact element (9). The device provides both a good seal, and strain relief to the completed connection.

Abstract: A surge arrester 2 comprises eight surge arresting varistor blocks 4 stacked within a polymeric outer insulating housing 14. A fibre optic cable 16 is fed into the surge arrester 2 through one end electrode 6, helically wound around all the blocks 4 in good thermal contact therewith and exits through the same electrode 6. A monitoring arrangement 18 compares the light incident on and emergent from the optical cable 16 to determine its integrity and thus the integrity of the surge arrester 2.

Abstract: An electrical cable in-line or branch joint has hydrophobic material located around the connections of the conductors so as to act as a water block. The hydrophobic material is physically prevented from being forced away from the connections into the cables, for example by pressure of water within the cable, by a fibrous material located in and around the crutch regions where the conductors emerge from the cable joints.

Abstract: A method of forming a sheet of material with indicia thereon comprises applying indicia to the sheet by an electrostatic copying process in which a toner powder is deposited on the sheet and is heated to cause it to fuse. The sheet of material comprises a flexible support layer that is provided with a porous coating of a latent curable material, preferably in particulate and/or filamentary form and especially one based on an epoxy material.It has been found that the indicia are more indelible than those formed on other surfaces by the same process even though the fused toner is not absorbed by the curable material.

Abstract: A metal facade construction having a heating device acting as a building heating system in a supporting structure located on the inside of the building can be obtained by arranging, on the supporting structure, heating cables in grooves of the metal profiles forming the supporting structure. These heating cables contain, inside an insulated enclosure, a temperature-sensitive heating conductor material which, in the event of a local temperature increase in a specfic portion of the heating cable, increases its specific resistance in that portion and thereby reduces the heating capacity in order to reduce its temperature in that heating cable portion, so that the heating cable exhibits a self-regulation property over its entire length.

Abstract: An electrical component, such as a joint between bus bars, is insulated by wrapping therearound a sheet of gel-like material, and manually causing it to conform to the joint. The material is curable by ultra-violet radiation, and this is directed on to the wrapped sheet to cause it to harden. A recoverable tube may be mounted over the sheet, before or after curing, to provide additional protection.

Abstract: A high voltage bushing is formed from a plurality of insulating layers. Conductive layers are interleaved with the insulating layers, and are electrically insulated from each other. The ends of the conductive layers are overlapped by stress grading layers, to minimize the electrical stress on the bushing.

Abstract: A joint between high voltage cables is formed by employing a connector having the same diameter as the cable dielectric. A layer of stress controlling material extends from the cable screen on one side of the joint, along the cable dielectric, across the connector, along the dielectric of the other cable and on to the screen of the other cable. A layer of conducting material extends on top of the stress controlling layer and longitudinally encompasses the conductor connector and overlaps the dielectric of both cables. An insulating layer encloses the conductive layer. Further layers of conductive and/or stress controlling material may be applied around the joint. In addition to being used in the formation of a joint between high voltage cables, a layer of stress controlling material with a layer of conducting material on its outer surface is employed in forming a termination of a high voltage cable.

Abstract: A surge arrestor comprises at least one surge arresting element mounted between a pair of electrodes. The assembly is secured together longitudinally by a plurality of heat recoverable polymeric strands, and is contained within a heat recoverable shedded polymeric housing of electrically insulating and non-tracking material.

Abstract: A seal in an aperture, e.g., a duct, is made by foaming a foamable substrate within an envelope in the aperture, to expand the envelope, which desirably has sealant or adhesive on its outer surface, to conform it into sealing engagement with the aperture. The envelope is closed and is of wraparound configuration so as to seal a large variety of aperture sizes, whether empty or containing objects, such as cables.

Abstract: A cable connection is described. It is particularly suitable for a piezoelectric cable which has a low melting point conductor. The connection is made by inserting a conductive piercing member such as a wire (14) into the conductor (4), so as to leave a portion of the piercing member extending from the cable. The piercing member (14) is then heated to the softening temperature of the cable conductor (4) to allow local softening of the conductor. The result, on cooling, is a solder joint between the piercing member and the cable conductor.

Abstract: Connection between a high voltage electric cable and the bushing of a transformer is achieved by firstly terminating the cable using heat shrinkable insulation tubing and stress control material, and secondly push-fitting the terminated cable into an insulating elbow. Mechanical retention of the cable in the elbow also provides electrical connection therebetween, for subsequent connection on to the bushing.

Abstract: A joint between a mass-impregnated paper insulated cable and a plastic insulated cable is sealed to contain the mass impregnating, oil material by applying a heat-recoverable oil resistant tubing over the exposed paper insulation so as to leave a portion thereof uncovered adjacent the exposed conductor of the cable, applying an oil resistant mastic to said uncovered portion of the insulation and over an adjacent end of said tubing, and applying a further heat-recoverable tubing over the mastic and an adjacent portion of the oil resistant tubing.

Abstract: An arrangement for and method of limiting the electrical stress in a region of high electric field strength associated with high voltage equipment, especially power cables, employs two overlapping layers of semiconductive material that have different a.c. electrical impedance characteristics to surround the region. The inner layer may be a heat-shrinkable tube having a linear characteristic, and the outer layer may have a non-linear characteristic and be provided as an internal coating on a further heat-shrinkable tube of insulating material. Such an arrangement provides good electrical protection in terms of both a.c. and impulse performance.

Abstract: An aperture, for example a duct having a cable passing through it, is sealed by installing a laminate, comprising an adhesive layer, a heater layer, and a heat-recoverable foam layer, the thickness of which increases on heating, into the gap between the duct wall and the cable with the adhesive layer facing both the wall and the cable. On energizing the heater, the foam increases in thickness and forces the adhesive into sealing engagement with the wall and cable.

Abstract: A tubular heat recoverable article has two layers in thermal contact, one inside the other. The two layers have appreciably different recovery temperatures. Shrinking of the article on to a substrate is effected by applying heat to the outer layer (1) of higher recovery temperature such that conduction to the inner layer (2) of lower recovery temperature ensures that the inner layer (2) reaches its recovery temperature, and thus becomes elastomeric, before the outer layer begins to recover. The article, which may be used in an electric power cable splice, thus combines good storage life with good recovery time.

Abstract: A joint between a mass-impregnated paper insulated cable and a plastic insulated cable is sealed to contain the mass impregnating, oil material by applying a heat-recoverable oil resistant tubing over the exposed paper insulation so as to leave a portion thereof uncovered adjacent the exposed conductor of the cable, applying an oil resistant mastic to said uncovered portion of the insulation and over an adjacent end of said tubing, and applying a further heat-recoverable tubing over the mastic and an adjacent portion of the oil resistant tubing.

Abstract: Enclosure for electrical apparatus comprising a first hollow sleeve of insulating material around which is positioned a second sleeve comprising an inner layer of insulating material and an outer layer of conductive material (normally connected to earth, e.g. a cable shield). This construction locates the major discontinuities of the material enclosure wall between layers of the insulating materials thus reducing the electrical stresses which could lead to insulation failure. The first sleeve may have an innermost laminated layer of stress grading material. Electrically conducting material may be present on the inner surface of the first sleeve to form a Faraday cage. Further sleeves may be interposed between the first and second sleeves to increase the insulation for higher voltages, and void filling compound may be used further to improve the electrical conditions within the enclosure.

Abstract: A connection for a ribbon cable wherein the cable conductors are bared to provide plug pins insertable into a socket member, and the cable has depressions or through holes between the conductors, which are engaged by projections within guiding extensions of the socket member to anchor the pins in the socket member. The cable may be doubled over and the conductors bared at the resulting U-bend to form a connection at any point along the cable, and the projections preferably enter a plurality of the depressions or holes in a symmetrical pattern from opposite sides of the cable. This connection has the advantages of low total volume and high resistance to mechanical jolting and vibration in use.

Abstract: Strip supply lead comprising a plurality of conductors embedded in a suitable insulating material (typically, a plurality of generally flat conductor elements in a strip of suitable polymeric material) is provided with a branch lead by first removing a portion of the insulating material in a zone intermediate the ends of the strip supply lead to expose a length of at least one of the conductor elements. The strip supply lead is folded about the midpoint of the bared conductor into a generally "U" shaped configuration to bring the surfaces of the portions on the intact strip supply lead immediately adjacent either end of the bared length of conductor forming the extremities of the shank of the "U" into an opposing relationship.