标准摘要
[中文适用范围]： IEC 60853 的这一部分提供了一种计算所有电压电缆的循环额定系数的方法，其中预期周围土壤会部分干燥。该方法基于 CIGRE 文档中发布的三种方法之一。该方法适用于任何类型的电缆，但建议仅适用于一根多芯电缆或三根单芯电缆的安装或电路间间距足以允许自由垂直的电路组。土壤水分在与每个回路相关的干土区域之间的移动。本标准并不排除在负载循环的全部细节未知的情况下使用其他计算方法。该方法假设电缆周围的整个区域在干燥之前具有均匀的热特性；唯一的不均匀性是由干燥引起的。因此，未经进一步考虑，该方法不应应用于使用具有与现场土壤不同特性的特殊回填材料的装置。注：1 计算周围土壤部分干燥的埋地电缆循环额定值的方法：Electra No 145，1992 年 12 月，第 32 页。 [外文原描述]： Gives a method for calculating the cyclic rating factor, for cables of all voltages, where partial drying out of the surrounding soil is anticipated. The method is based on one of the three methods published in a CIGRE document. The method is applicable to any type of cable, but it is recommended that it should be applied only to installations of one multi-core cable or to three single-core cables or to groups of circuits where the intercircuit spacing is sufficient to permit free vertical movement of soil moisture between the zones of dry soil associated with each circuit. This Standard does not preclude the use of other methods of calculation where full details of the load cycle are not known. The method assumes that the entire region surrounding a cable or cables has uniform thermal characteristics prior to drying out; the only non-uniformity being that caused by drying. As a consequence the method should not be applied, without further consideration, to installations where special backfills, having properties different from the site soil, are used.
英文名称Calculation of the cyclic and emergency current rating of cables - Part 3: Cyclic rating factor for cables of all voltages, with partial drying of the soil