ABSTRACT
The Programmable Logic Controller (PLC) as the main station, connect cart, trolley, load-lifting frequency converter by ProfiBus-DP, and all kinds institutions of the remote I/O slave station and encoder are connected to the upper computer and the driver room’s touch screen by using the cable. In the form of Ethernet, the intelligent network control system of large shipbuilding gantry crane is constituted. The electrical control room as the center of the whole electric control system, issue control instructions to various agencies of shipbuilding gantry crane, all kinds of protection signals (such as rising end signal, decreased end signal, hoisting weight limiter overload signal) will be collected by remote I/O slave station, then feedback to the PLC master station. The cabin is also a remote I/O slave station; it can realize the function of the man–machine communication and through the touch screen operator can observe the running state of the whole crane system. Encoder slave stations are able to detect the status of hoisting position data, and send them back to the PLC master station, the frequency converter internal fault information can also be transmitted to the PLC master station by frequency converter slave station.
