GB264731A - Improvements in or relating to electric cables - Google Patents

Abstract

264,731. Macintosh Cable Co., Ltd., and Williams, A. W. Dec. 23, 1925. Cores for cables; cables, arrangement and disposition of parts of; cables with auxiliary conductors.-Relates to electric cables of the kind comprising a plurality of insulated conductors, and consists in the provision of an earth core comprising an inner conductor 3a, Fig. II., and an outer metal sheath 3<c> insulated therefrom and adapted to constitute therewith a closed earthing circuit. Preferably the outer metal sheathing consists of a series of cords, each formed of twisted wire strands, helically twisted in one direction about the insulations 3<b> of the inner conductor. The sheath of the earth core may be in electrical contact with one or more of the power cores. In the arrangement shown in Fig. I. the power cores 2 are of dual construction, comprising an insulated inner conductor and outer metal sheath, and the earth core 3 is disposed centrally with its sheath in contact with the sheaths of all the power cores. Cushioning pads 4 may be disposed between the power cores. The application to systems of the kind described in Specification 209,831, [Class 38 Electric switches &c.], is referred to.