低压配电TN-S系统的重复接地及安全

Repeatedly Grounding and Safety for TN-S System

通过实例计算,比较了TN-S系统在无重复接地、有重复接地、有重复接地且PE线截面比相线低一级和PE线做成环路4种情况下的单相接地短路电流值和短路点的电压。结果表明,将PE线做成环路的方法可以取代重复接地。

Through the calculation of example, the short circuit current value of single phase grounding and the voltage of short circuit point were compared in TN-S system for the four cases i.e. without repeatedly grounding, with repeatedly grounding, with repeatedly grounding and the cross area of PE wire is one class lower than that of phase wire, making th PE wire to be circuit. The result indicates that the method making the PE wire to be circuit can replace the repeatedly grounding.