Les télégraphes anglais. sont pris en charge sur chaque bras transversal. Tous les pôles sont fournis avec des câbles de masse ou contacter con ductors pour transporter le mauvais temps s'échapper directement à la terre au lieu de lui permettre de fuir dans le fils voisins. Le fil de terre est constituée d'un morceau de No 8 du fil de fer galvanisé qui s'étend de la partie supérieure du poteau au fond et se terminant par une bobine plate fixer à la base du poteau de façon à exposer une surface aussi grande que possible de la terre. À partir de l'épaisseur des branches du fil de masse composée de 10 gal pas vanized fil de fer sont transportés dans des rainures vu coulé dans la croix

• Contributeur: Penta Springs Limited / Alamy Banque D'Images
• ID de l’image: 2ABWBRP
• Taille du fichier: 43,8 MB (3,1 MB Téléchargement compressé)
• Autorisations: Modèle - non | Propriété - non
• Dimensions: 3316 x 4614 px | 28,1 x 39,1 cm | 11,1 x 15,4 inches | 300dpi
• Date de la prise de vue: 2 octobre 2019
• Photographe: Corantos

Informations supplémentaires

Cette image peut avoir des imperfections car il s’agit d’une image historique ou de reportage.

THE ENGLISH TELEGRAPHS. are supported upon each cross arm. All the poles are provided with earth wires or contact con ductors for carrying the wet weather escape directly to the earth instead of permitting it to leak into the neighboring wires. The earth wire consists a piece of No 8 galvanized iron wire extending from the top of the pole to the bottom and terminating in a flat coil attached to the foot of the pole so as to expose as large a surface as possible to the earth. From the thick earth wire branches composed of No 10 gal vanized iron wire are carried in saw grooves sunk in the cross arms and soldered to the insulator bolts. The work is the top of the poles and serve an excellent purpose as light. Ding arresters. Great care is taken to keep the poles in a rigidly upright position ; and in addition to placing them well in the ground and tamping the earth thoroughly around them they are well supported with stays made of wire ropes attached to iron rods which run into the ground about four feet. On straight lines and slight curves where exposed to the winds double stays are employed. The insulators on the railway routes are uniformly of the Varley double cone brown ware pattern and those upon the canals and highways of the single cone white ware or porce lain. The Varley insulator is regarded as the best but its greater cost has 'prevented its exclusive use. The conductors employed upon the English lines are com posed of zinc-coated iron wires of Nos. 4 8 and gage. The No. 8 gage-0 170 inch diameter—is the size in general use: the No. 4 gage-0.240 inch diameter—being employed upon a few of the long circuits between the more important lines only. The method formerly followed of allowing the wires to pass freely through the insulators and fastening them only at distances of half a mile has been abandoned in favor of bind ing them at every pole No. 16 charcoal wire being used for binding. JOINTING THE WIRES. that known as the Britannia joint. This is made by

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• conducteurs de contact
• cross arm
• échapper à la pluie directement
• fils de terre
• poteaux
• provided
• soutenu sur
• télégraphes anglais
• terre
• transportant