AC/DC water-cooled load box, the power input adopts segmented combination control, supports sudden addition/unloading test, the resistive load adopts energy-consuming working mode, and water-cooling heat dissipation greatly ensures the reliability of constant power discharge. The water-cooled load box is mainly used to test the output power and load capacity of the ship's generator set, and to test all electrical parameters including dynamic parameters. It is used in conjunction with the host computer to achieve intelligence and automation, and complete special testing of all electrical parameters of the generator set. At the same time, charts, curves and test reports are generated to provide scientific testing methods for ship generator equipment.