根据国外普遍采用重复接地TN C S系统的情况，分析重复接地电阻的主要作用、取值等有关问题，供建筑供电设计参考。
According to the re-earthing TN-C-S systemadopted usually by foreign country, the paper analysesmainfunction, value etc.of re-earthing resistance. These respects can be referenced for designer.