ITU-T Recommendations

This Recommendation seeks to establish fundamental testing methods and criteria for the resistibility of telecommunication equipment to overvoltages and overcurrents.Overvoltages or overcurrents covered by this Recommendation include surges due to lightning on or near the line plant, short-term induction of alternating voltages from adjacent electric power lines or electrified railway systems, earth potential rise due to power faults, and direct contacts between telecommunication lines and power lines.Major changes compared with the 2000 version of this Recommendation include:
• replacing the longitudinal test with a port to earth test;
• the introduction of an external port to external port test;
• adding internal port requirements.