The "three-phase three-wire" power supply mode of the new power grid reconstruction project enhances the insulation level of the distribution line, improves the power supply reliability, and reduces the line loss. However, single-phase grounding faults often occur, especially in severe weather conditions such as strong wind, rainstorm and hail, which seriously affect the normal operation of the power grid. After the fault occurs, due to the wide range of wire length, it is difficult to find the fault point quickly and accurately by using traditional methods for troubleshooting.

    Single-phase grounding fault point patrol device for distribution lines (abbreviated as patrol assistant) is used for finding single-phase grounding fault points of 6kV, 10kV, 20kV and 35kV overhead lines. For concealed grounding faults such as porcelain bottle breakdown and lightning arrester breakdown, it is necessary to find them quickly, reduce the work intensity of line maintenance personnel, save time and labor, and improve work efficiency, power supply reliability and economic benefits of power enterprises.