电缆 电流定额的计算 第2部分:热阻 第1节:热阻计算

[中文适用范围]： IEC 287分为三个部分，以便更方便地进行文件的修改和补充。每个部分都分为几个部分，这些部分作为单独的标准发布。本节包含方法 [外文原描述]： Is solely applicable to the conditions of steady-state operation of cables at all alternating voltages, as well as in direct voltages up to 5 kV, buried directly in the ground, in ducts , in troughs or in steel pipes, both with and without partial drying-out of the soil, as well as cables in air.