电缆 额定电流的计算 第 3-1 部分：工作条件 现场参考条件

[中文适用范围]： IEC 60287-3-1:2017 RLV 包含官方 IEC 国际标准及其红线版本。 Redline 版本仅提供英文版本，为您提供了一种快速、简单的方法来比较官方 IEC 标准与其先前版本之间的所有更改。 IEC 60287-3-1:2017适用于直接埋在地下、管道、槽或钢管中的电缆在所有电压下的稳态运行条件，无论土壤是否部分干燥，以及空气中的电缆。术语“稳态”旨在表示刚好足以渐进地产生最大导体温度的连续恒定电流（100%负载系数），假设周围环境条件恒定。本文件定义了现场参考条件，但一般值将被具体的国家要求所取代。与前一版本相比，该版本包括以下重大技术变化： - 更新后的国家铺设条件清单现已包含在附件 A 中； - 删除了有关购买者选择适当类型电缆所需信息的第 5 条。 [外文原描述]： IEC 60287-3-1:2017 RLV contains both the official IEC International Standard and its Redline version. The Redline version is available in English only and provides you with a quick and easy way to compare all the changes between the official IEC Standard and its previous edition. IEC 60287-3-1:2017 is applicable to the conditions of steady-state operation of cables at all voltages, buried directly in the ground, in ducts, troughs or in steel pipes, both with and without partial drying-out of the soil, as well as cables in air. The term "steady state" is intended to mean a continuous constant current (100 % load factor) just sufficient to produce asymptotically the maximum conductor temperature, the surrounding ambient conditions being assumed constant. This document defines site reference conditions, however the general values are superseded by specific national requirements. This edition includes the following significant technical changes with respect to the previous edition: - the updated list of national laying conditions is now covered in Annex A; - Clause 5 about the information required from the purchaser for the selection of the appropriate type of cable has been removed.