In case of armoured cables, generally galvanized steel wire / strip armouring is provided over the innersheath in multi-core cables and Aluminium Round Wire or Aluminium Strip over the insulation in single core cables.

It provides mechanical protection to inside cores and it carries earth return current in case of a short circuit of a core with armour. As per I.S. 1554 & I.S. 7098, round wire armouring is provided in cable, where calculated diameter under armour is upto 13 mm. Above this the armouring is either with round wire or strip of size 4 mm x 0.80 mm.