标准摘要
[中文适用范围]： IEC 60287的本部分适用于直接埋在地下、管道、槽或钢管中的电缆在所有交流电压和高达5 kV的直流电压下的稳态运行条件，无论有或没有部分土壤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。本部分提供了电流额定值和损耗的公式。给出的公式本质上是字面的，并且故意保留某些重要参数的选择。这些参数可分为三组： – 与电缆结构相关的参数（例如，绝缘材料的热阻率），其代表值是根据已发表的工作选择的； – 与周围条件相关的参数，这些参数可能变化很大，其选择取决于电缆使用或将要使用的国家； – 由制造商和用户之间协议产生的参数，涉及服务安全裕度（例如，最大导体温度）。 [外文原描述]： Applicable to the conditions of steady-state operation of cables at all alternating voltages, and direct voltages up to 5 kV, 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. Provides formulae for current ratings and losses. The formulae given are essentially literal and designedly leave open the selection of certain important parameters. These may be divided into three groups: - parameters related to construction of a cable (for example, thermal resistivity of insulating material) for which representative values have been selected based on published work; - parameters related to the surrounding conditions, which may vary widely, the selection of which depends on the country in which the cables are used or are to be used; - parameters which result from an agreement between manufacturer and user and which involve a margin for security of service (for example, maximum conductor temperature).
英文名称Electric cables - Calculation of the current rating - Part 1-1: Current rating equations (100 % load factor) and calculation of losses - General