Warehouse bridge crane inverter control system based on PLC

LIU Zhi-gang1， YANG Bo-jun2
（1. Xingtai Waste Water Treatment Plant， Xingtai 054001， China；
2. School of Mechanical Engineering， Hebei University of Technology， Tianjin 300401， China）

Abstract： Aiming at the problems of a large volume，poor reliability，high failure rates on the traditional bridge type crane control system，a new control system based on PLC and variable frequency control was designed. In the system，the speed and direction of crane motor were controlled by PLC-based inverter. The back，forward and lift speed regulations were realized. After analysis of the principle，the automatic protection relation between the PLC and the system of power and security was established in the control system. The structure of the control system was designed. Hardware components and wiring diagram of the control system were given. The software of the control system based on Omron PLC was written and the software ladder diagram was given. The experiments of installation，commissioning and operation were done on the control system of the warehouse bridge crane. The results indicate that the improved bridge type crane control system is small，operates stably and reliably，reduces resource waste.
Key words： warehouse； bridge crane； control system； PLC； inverter