16 sq mm aluminium cable current carrying capacity2xfy cable full form3.5 core copper cable current rating chart35 sq mm 4 core aluminium cable current capacity4 core aluminium cable current rating50 sq mm aluminium cable current carrying capacitya cable is designated as yfya2xfy cable meaningaluminium armoured cable current carrying capacityayfy cable current ratingayfy cable meaningdifference between xlpe and ayfyfull form of cablepolycab aluminium cable current rating chartxlpe cableyry cable