Source google image: https://www.legrand.fr/sites/default/files/styles/1222×569/public/schema-cablage-double-va-et-vient-1222×569.jpg?itok=0tp94JZJ
Schema double va et vient electrique
Source google image: https://www.legrand.fr/sites/default/files/styles/1222×569/public/schema-cablage-double-va-et-vient-1222×569.jpg?itok=0tp94JZJ