控制系统工作原理
(1) 基本逻辑控制过程。
PLC逻辑控制流程见图2所示。PLC是按照重复扫描的方式执行它的操作，它使PLC中的用户程序逐行被解读，并按照操作信号发出的控制命令，实现对液压系统工作过程的控制。
Control system working principle
(1) 基本逻辑控制过程。
(1) basic logic control process.
PLC逻辑控制流程见图2所示。PLC是按照重复扫描的方式执行它的操作，它使PLC中的用户程序逐行被解读，并按照操作信号发出的控制命令，实现对液压系统工作过程的控制。
PLC logic control flow is shown in Figure 2. PLC is in accordance with the repeated scanning of the implementation of its operation, it makes the PLC user program line by line interpretation, and in accordance with the operation of the signal from the control command to realize the control to the working process of the hydraulic system.
