Main bonding

(Main protective equipotentail and supplementary bonding)

Main protective equipotential bonding (‘main bonding’, for short) is an essential part and required in the majority of electrical installations.

Main protective bonding conductors shall connect to the main earthing terminal to all extraneous-conductive-parts including the following:

  1. water installation pipes
  2. gas installation pipes
  3. other installation pipework and ducting
  4. central heating and air conditioning systems
  5. exposed metallic structural parts of the building


Main Bonding 1

Supplementary equipotential bonding (‘supplementary bonding’ for short) is considered as additional protection against electric shock under fault conditions, Supplementary bonding involves connecting together the conductive parts of electrical items and non-electrical items,, to prevent the occurrence of a dangerous voltage between them under earth fault conditions.

Main Bonding 2