For the control of elevator control system, there are three ways: relay control, microcomputer control and PLC control. For the other two ways, PLC control has a very obvious advantage. It has many advantages, such as long use time, high degree of automation, good job safety performance and so on. Among the three control modes, only it is the most reliable and convenient. In addition, its operating system is easy to expand. No matter small elevator or large elevator, it is very suitable for use. At present, PLC is developing rapidly..