在现代化的工业生产设备中，有大量的数字量及模拟量的控制装置，例如电机的起停，电磁阀的开闭，产品的计数，

温度、压力、流量的设定与控制等，工业现场中的这些自动控制问题，若采用可编程序控制器( P C ) 来解决自动控制问题已成为

最有效的工具之一，本文叙述P C 控制系统设计时应该注意的问题。-In modern industrial production equipment, there are a large number of digital and analog control devices, such as motor starting stop, solenoid valve opening and closing, product count, temperature, pressure, flow and control settings such as, industrial site automatic control of these problems, the use of programmable logic controller (PC) to solve the automatic control issue has become one of the most effective tool, this article describes the design of PC control system should pay attention to.