Realizing Multi-crane Center Control Of Long Rail Crane With Siemens PLC

Welded long rail is the base of continuous railroad. Long rail cranes in the most important flight is used to swing long rail in the product line, which control method is each worker control each single crane. This method needs more workers and also have hign accidental frequency, undependable ability. These make it bottleneck of the line and result in low productivity. With the more needs of continuous railroad, the development of congregative control of long rail crane is more imperative under the situation.In this paper, the equipment of welded railway factory , the long rail cranes are introduced. The designing requirements is given. The control system selects PLC controller and some monitor equipment.Base on the core of the control system-PLC, the PLC hardware circuit, PLC I/O connecting circuit, monitor system hardware circuit, motor control system hardware circuit, signal indication of long rail reaching circuit, long rail position adjusting of long rail are designed. According to the hardware circuits, the main, assistant and monitor control panels are given. The debugging of PLC hardware shows that CPU, I/O modules, Ml 53 work well and the designing of PLC hardware is correct.The software is programmed on the flat of STEP7 software package. The main program, single crane controlling subprogram, congregative cranes controlling subprogram, resetting subprogram, motor overhauling subprogram are compilered. The results of the debugging with PLC simulation software package show that the software of this system can satisfy the requirements of the designing.Based on the designing of hardware and software of this system, the simulating system which only includes two cranes' running is debugged. The inputting parts and some outputting parts are connected to PLC. The results show that this control system can satisfy requirements of the spot and be applied to the spot.