Fault position marking robot for power grid line detection

The utility model relates to a fault position marking robot for power grid line detection, which comprises a mounting plate, a positioning mechanism for marking a fault position is arranged in the middle of the mounting plate, and a fixed seat is fixedly connected to the top of the mounting plate on one side of the positioning mechanism; when the detection tool finds a fault, an electric push rod is started to extend to drive a rotating frame to rotate, so that a pen point of a marking pen draws a mark on a power grid line, and meanwhile, due to extrusion between the bottom of a sponge block and a supporting frame, a fluorescent agent in the sponge block is smeared on the power grid line; the situation that the position of a fault is inconvenient to observe at night is avoided, the position of the fault can be accurately determined no matter in the daytime or at night, the fault positioning efficiency is improved, when the L-shaped plate rotates to reset, a fluorescent agent in the liquid storage tank is inje