Patent GB-191323348-A (GB)
Title: Electric Switch Gear in which all Current Carrying Parts are Immersed in Oil or Embedded in an Insulating Mass.
IPC: H02B13/02
Filed: 1913-10-15
Granted: 1915-06-17
Abstract: 23,348. Allegemeine Elektricitõts Ges. Oct. 15, 1912, [Convention date]. Oil switches; switchboard details.-Switch gear for high-tension currents comprises a number of separate units, each unit being constituted by a section of a divided bus-bax enclosed in a chamber, and an oil switch, the separate bus-bar sections of the different units being linked up by removable plug connectors, and all the current-carrying parts being immersed in an insulating-medium. In the arrangement shown on Fig. 1, each of the separate chambers a contains a three-phase bus-bar section b and an oil switch c. The removable plug connectors e fit into openings of adjacent bus-bar chambers and carry conducting-pins 5, which fit into sockets 3 formed in the ends of the bus-bar sections, thus linking the separate sections together. For leading current from the bus-bars to branched-off circuits, plug connectors 12 at the ends of the branch-circuit cables 11 join on to the oil-switch contacts. The chamber a is filled with oil or a non-freezing resinous liquid; the bodies of the plug connectors are filled either with an insulating- liquid or an insulating-mass. By taking out plug connectors, any one section can be rendered dead, and in order, in that case, to keep the remaining section in use, the end units may be joined together by a cable long enough to admit fresh units as required. In the arrangement shown in Fig. 2, the oil switch of each unit is in a compartment f and the bus-bar section in a compartment g, the one compartment fitting into the other. The supply and return cables are led into separate bus-bar section chambers, which are not fitted with oil switches. Self-closing lids l are provided for the plug-connector openings. The lids may be operated by guide-members on the plug connectors so as to close when the connectors are withdrawn and open again during the replacement of the connectors. Automatic locking-catches, which require to be unfastened by keys, may be provided to prevent the replacement of the connectors and the consequent opening of the lids, the guide-bars, in this case, allowing the connectors to be sufficiently raised, but not completely detached. Further provision for safe-working is made by interlocking the bridging plug-connectors and the switches of adjacent units in such a manner that the switch of a given unit must be opened before the adjacent plug connectors can be removed to cut the unit out of the series. One construction for this purpose is shown in Fig. 6. Rods b, which are depressed when the switches are opened, are jointed by bell-crank levers c and links d to spring-controlled locking-bolts, so that the opening of any switch withdraws all the bolts from engagement with two adjacent slug connectors. In a modified construction, the two separate bolts are replaced by a pair of pivoted locking-pawls, coupled together and controlled by a spring. In a further modified construction, the locking-mechanism is provided with devices which block the openings of the plug connectors adjacent to a switch if the switch is closed, while both of the corresponding plug connectors are out. If only one connector is out, however, the closing of the switch does not prevent replacement of the connector.