本标准为电站GPR和LI电压的计算提供了指南，并为金属电信保护设计中使用的最坏情况值的适当降低提供了指南。还包括用于确定以下各项的信息: a） 故障电流和接地回路电流水平；它们的概率、波形和持续时间；以及在这些GPR和LI计算中使用的远程接地点阻抗，以及 有效X/R比。 b） 电站探地雷达的影响区（ZOI）。 c） 感应电流、功率与金属材料之间的互阻抗的计算 电信设施和屏蔽因素。 d） 非金属电信设施的信道时间要求- 继电保护需要可中断通道。

This standard provides guidance for the calculation of power station GPR and LI voltages and guidance for their appropriate reduction from worst-case values for use in metallic telecommunication protection design. Information is also included for the determination of the following: a) The fault current and the earth return current levels; their probability, waveform, and duration; and the impedance to remote earthing points used in these GPR and LI calculations as well as the effective X/R ratio. b) The zone of influence (ZOI) of the power station GPR. c) The calculation of the inducing currents, the mutual impedance between power and metallic telecommunication facilities, and shield factors. d) The channel time requirements for metallic telecommunication facilities where non-interruptible channels are required for protective relaying.