ITU-T K.66 (06/2011)
|Protection of customer premises from overvoltages|
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;
• 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 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).