The Application Of Rockwell PLC And ABB Inverter In Portal Slewing Crane’s Control System

Based on other types of cranes, portal slewing crane, a kind of large track-type bulkmaterial processing equipment, came into being due to the great demand of porttranspiration. Since then, it has become the major portal machinery employed in generalcargo wharfs because of its large lifting height and capacity, long boom, broad workingarea, flexibility, accurate positioning and universal application. The body of the paper is asfollows:Firstly, it focuses on large cargo handling facilities----the significance, history ofportal slewing crane and its evolution into large machinery and high automation. Besides,it briefly introduces the current status of its control system.Secondly, this paper proposes tentative controlling methods and controlling subjectsof portal slewing crane after analyzing its process, structural composition and operatingprinciples. Moreover, it brings forward demands on electrical control system of cargohandling based on the study on its operation system.Finally, it presents a design of hardware and software in electrical control system ofportal slewing crane, using Rockwell PLC, ABB inverter, the industrial field bus and HMIinterface. In the plan of hardware design, the paper gives part of the main circuit and PLCconfiguration diagram of electrical controlling system as well as the PROFIBUS-DPprotocol data. In the plan of software design, it gives a detailed controlling flowchart,main program and subprogram of PLC. And it comes up with debugging procedures andthe solutions to the possible problems.The portal slewing crane investigated has been operated for many years and it hasbeen proved to be simple and secure in operation, low in maintenance cost and high inefficiency. Therefore, it should be widely used in portal transportation for its remarkableeconomic returns.