GB931870A - Improvements in or relating to arrangements for the overhead support of electrical apparatus, for example roadway lighting fittings - Google Patents

Abstract

931,870. Supporting cables. GENERAL ELECTRIC CO. Ltd. Dec. 18, 1960 [Nov. 25, 1960], No. 40636/60. Class 36. [Also in Groups XI and XXXVII] An arrangement for the overhead support of electrical apparatus, especially roadway lighting fittings, consists of a diamondshaped wire network attached at or from a first pair of opposite corners to a pair of upstanding posts, catenary support wires being attached to the second pair of corners and extending out to attachment points, e.g. the corresponding comers of preceding and succeeding wire networks, so that all the wires are normally maintained in tension, electrical apparatus such as lighting fittings and a supply cable therefor being attached to one or both support wires and a safety wire normally slack or at low tension being connected between the second pair of comers so that if the network supporting tension at the first pair of corners disappears, the safety wire will be tensed to reduce the sagging of the catenary support wires. In an arrangement for a road having a dual carriageway, posts 6, 7, Fig. 1, are erected opposite one another at intervals and support a double diamond network 8, 9 at the outer comers. The opposite corners of each diamond are connected by support wires 10, 11 to the corresponding corners of preceding and succeeding diamonds, supply wires 18, 19 being suspended from the wires 10, 11 by insulated hangers 20, 21. Lighting fittings 16, 17, e.g. for sodium lamps, are suspended at intervals along the wires 10, 11. Safety wires 22, 23 connect the corners of each diamond to which the support wires are attached and may incorporate means for earthing the supply wires in the event of a breakage. For this purpose, one corner 28, Fig. 3, of the diamond is connected to the lower end of an arm 26, the upper end being connected to the other corner 29. The arm 26 has a horizontal portion 27 carrying a cross-bar 32 for facilitating earthing contact with the supply wire 18. Weak links 30, 31 are connected between the upper end of the arm 26 and the corner 28 and between the safety wire and the portion 27 to prevent accidental operation of the earthing device as a result of wind stress, tensioning of the safety wire causing the links to break so that the arm 26 is pulled horizontal and the cross-bar 32 makes earthing contact with the wire 18.