Summary

Bonding and earthing of telecommunication installations are done for reliability and personal safety reasons. The evolution of the power architecture of telecommunication systems has created new installation conditions for equipment. To cover these situations, bonding and earthing configurations need to be defined to ensure that adequate reliability and safety are maintained.

Recommendation ITU-T K.73 analyses the situation in which equipment connected together are installed in different buildings with different earthing and power feeding conditions.

This Recommendation also includes the installation requirements for equipment located in different buildings, which have the same earthing and feeding power conditions, to improve the shielding and bonding of telecommunication and power cables between buildings.

Other Recommendations dealing with bonding and earthing are Recommendation ITU-T K.27, Bonding configurations and earthing inside a telecommunication building, Recommendation ITU-T K.35, Bonding configurations and earthing at remote electronic sites and Recommendation ITU-T K.66, Protection of customer premises from overvoltages. These Recommendations do not cover how equipment installed in these different environments can be interconnected.