ITU-T Recommendations

Recommendation ITU-T K.66:

• provides recommendations for bonding and earthing of telecommunication equipment in residential and commercial customer premises;

• refers to Recommendation ITU-T K.21 (2008) for equipment resistibility requirements;

• recommends earthing and bonding requirements to coordinate with the resistibility requirements of Recommendation ITU-T K.21 (2008) and the safety requirements of IEC 60950-1 and IEC 62368-1;

• recommends the installation practices for bonding of all services and the installation of surge protective devices (SPDs);

• illustrates problems associated with earthing and bonding and provides solutions for these earthing and bonding problems. These include:

1) methods to improve the earthing and bonding;

2) methods of providing additional protection external to the equipment;

3) special resistibility and safety requirements;

• recommends responsibilities for protection at customer premises;

• refers to IEC 62305-3 for protection against direct lightning.

This revision of Recommendation ITU-T K.66 includes an update of the references and a revision of clause 6.3 to include more information on preventing equipment damage. Appendix IV, containing information on special resistibility requirements has been deleted; the reader is directed to Recommendation ITU T K.44 (2008).