Abstract: A system for time synchronization between multiple operating systems is provided, the system includes a Field Programmable Gate Array (FPGA) configured to obtain and maintain absolute time; and multiple operating systems (OS) that obtain the absolute time from the FPGA and perform time synchronization based on the obtained absolute time. According to the embodiments of the present disclosure, the system can solve the high accuracy time synchronization problem in a protection relay device with multiple operating systems.

Abstract: A self-cleaning device of a filtering net of air conditioner is installed on a filtering frame in an air inlet of a dust spiral case of a package air conditioner and is disposed outside the filtering net. A filtering net guide rail with slots is installed on an upper frame and a lower frame. The filtering net is fixed on the filtering net frame by the slots of guide rails. The cleaning device of the filtering net includes a sweeping assembly with a brush, a drive motor fixed on the sweeping assembly, a transmission mechanism connected to the drive motor, a rack group installed on the left and right side of the filtering net, a dust collecting box installed under the filtering net for collecting dust, and a dust exchanging device is disposed between the dust collecting box and the filtering net.

Abstract: A self-cleaning device of a filtering net of air conditioner is installed on a filtering frame in an air inlet of a dust spiral case of a package air conditioner and is disposed outside the filtering net. A filtering net guide rail with slots is installed on an upper frame and a lower frame. The filtering net is fixed on the filtering net frame by the slots of guide rails. The cleaning device of the filtering net includes a sweeping assembly with a brush, a drive motor fixed on the sweeping assembly, a transmission mechanism connected to the drive motor, a rack group installed on the left and right side of the filtering net, a dust collecting box installed under the filtering net for collecting dust, and a dust exchanging device is disposed between the dust collecting box and the filtering net.