Neutral groundingresistor is used to decrease transient overvoltage when single-phase grounding,eliminate arc flash hazard and quickly locate the fault line and clear it up.This system is applicable to 6-35KV power distribution grid of cable lines incities, large industrial enterprises, factories, airports, seaport and etc, aswell as 0.66KV system in mine digging and 0.4KV/6KV/10KV system in powerplants.