The embodiment of the utility model discloses general PLC device under water that possesses high definition video transmission path, include: a host system for PLC's whole detection and control, a signal acquisition module detects the mouth including high accuracy analog to digital conversion circuit, digital analog conversion circuit and digital quantity and forms, is connected with host system, a power -balance module for that detects entire system uses the electric power circumstances, prevents that the too big damage power of power is and provide necessary output, a power module is connected with host system for accomplish opening, closing of external solenoid valve, the control and the fault detection of motor, host system, power management module, signal acquisition module, power -balance module, power module, communication module, rectifier module and host system set same mechanical mounting dimension's circuit module to. The utility model discloses make this system to realize the different tactics that observe and control through the programming on different underwater kits and instrument and equipment to can directly be applied to and work under water.