1.1 This standard applies to 60 – 250°C single- or multiple-conductor jacketed or unjacketed, integral or nonintegral cables and single or multiple coaxial cables for telephone and other communication circuits s...
详细信息
标准号:
UL 444-2008
1.1 This standard applies to 60 – 250°C single- or multiple-conductor jacketed or unjacketed, integral or nonintegral cables and single or multiple coaxial cables for telephone and other communication circuits such as voice, data, and audio for on-premise customer systems. These cables are not prohibited from containing one or more optical fibre members. For the purpose of this standard, a coaxial cable or coaxial member conductor is a single conductor with a shield. For the purpose of this standard, a single- or multiple-conductor unjacketed cable is a cross-connect wire.1.2 This standard applies to communications cables that are intended primarily for installation inaccordance with Section 60 of the Canadian Electrical Code (CEC), Part I, and Article 800 of the National Electrical Code (NEC), ANSI/NFPA 70. They are rated for 300 V applications but are not so marked.1.3 This standard does not apply to communications cords.1.4 In Canada, Type CMUC, cross-connect communications cables, and the "-CI" circuit integrity markings are not recognized by the Canadian Electrical Code, Part *** the US, Type CMH is not recognized in the NEC.1.5 If a value for measurement is followed by a value in other units in parenthesis, the second value may be only approximate. The first stated value is the requirement.
1 This standard applies to 60-250°C single- or multiple-conductor jacketed or unjacketed, integral or nonintegral cables and single or multiple coaxial cables for telephone and other communication circuitssuch as...
详细信息
标准号:
UL 444-2002
1 This standard applies to 60-250°C single- or multiple-conductor jacketed or unjacketed, integral or nonintegral cables and single or multiple coaxial cables for telephone and other communication circuitssuch as voice, data, and audio for on-premise customer systems. These cables ale not prohibited from containing one or more optical fibre members. For the purpose of this standard, a coaxial cable or coaxial member conductor is a single conductor with a shield. For the purpose of this standard, a single- or multiple-conductor unjacketed cable is a cross-connect wire.2 This standard applies to communications cables that are intended primarily for installation in accordance with Section 60 of the Canadian Electrical Code (CEC), Part 1, and Article 800 of the National Electrical Code (NEC) . They are rated for 300 V applications but are not so marked.
采用带精英策略的非支配排序遗传算法(NSGA-Ⅱ)对通信电缆的绞合节距进行优化,以通信电缆的导体用量和近端串音衰减为优化目标,获得一组多样化的Pareto解集,为绞合节距的设计提供了优选空间.以25线对通信电缆的绞合节距为优化对象,结果表明,经优化获得157个Pareto解,其目标函数导体用量位于区间[55.93 kg/km,56.74 kg/km],近端串音衰减位于区间[58.11 d B/km,94.77 d B/km];与粒子群算法(PSO)相比,在收敛时长相似的情况下,NSGA-Ⅱ的优化结果支配度100%优于PSO,其解集分布均匀程度也显著优于PSO.
暂无评论