The utility model relates to a low tension cable ac voltage withstand test equipment, including control box and oil -immersed transformer, oil -immersed transformer includes iron core and outside primary side winding and vice limit winding, primary side winding and the transformation ratio of vice limit winding be 3000200. The utility model discloses the equipment transformation ratio is little, and test voltage easily controls, and it is experimental to be applicable to various low tension cable ac voltage withstand test simultaneously, and the instrument is light, and it is more convenient to change experimental wiring, thoroughly solves this cumbersome difficult problem of output voltage out -of -control.