Friday, February 12, 2016

Electrical installations specifications


  • The masonry chamber for earthing should have brick masonry foundation.
  • The chamber should be constructed in such a manner that 40 mm diameter G.I. pipe earth electrode is at the center of the chamber.
  • The pipe electrode should be buried to the correct level such that its top is not less than 20 cm below ground level.


  • Before fixing switch boxes in the wall, the space behind switch boxes should be filled with mortar properly.
  • The height of power plug/ light plug should be kept at least 125 cm above the floor and 30 cms above kitchen platform level.
  • The accessories like bell push, light, control switch, socket, etc. if provided in an area exposed to rain, they should be suitably protected by providing covers.
  • Wires should be drawn in the conduit before plastering.
  • Shock protector unit is to be provided to prevent any untoward happening in the building.
  • The in coming supply of power from the street should be through a cable of adequate size and laid in a pucca cable trench covered with RCC slab.  
  • Installation of MCB-DB is preferable, since it will protect the wire from damage, due to over-loading.
  • All wires between which a difference of potential of 240 volts exists shall be made inaccessible to unauthorized persons or enclosed in a conduit.