ITU-T Recommendations

This Recommendation provides protective procedures against accidental contacts between power lines and telecommunication lines, when these lines use the same poles. The procedures are primary intended to reduce the risk of an accidental contact (power-cross). However, in the case of a power cross, the protective procedures mitigates its consequences. This Recommendation provides a set of clearance values between power and telecommunication lines at the joint-use pole and the rules for achieving the insulation coordination between the lines. In the case of a power-cross, the earthing and bonding procedures are intended to assure the immediate tripping of the power line circuit breaker. As a backup protection, this Recommendation requires the use of surge protective devices at the customer premises whenever there is a joint-use of poles with medium voltage power lines.