After the power supply is connected, the whole system starts to work by pressing the start button on the control panel. The centralized control system, ACS800 frequency converter, hydraulic holding brake system, reducer, upper computer, electronic belt scale weighing device, etc. are started according to the sequence set by the program. At the same time, PLC detects the status of feedback of each external switch to determine how to control. The control process and structure are shown in Figure 2-3 below: