本文是作者工作实践的总结。介绍的主要内容是研究将继电器组合起来,用少量继电器控制较大量的对象,加强通用性和灵活性,并且赋予记忆功能,以便使用于生产自动线、远距离控制和显示等方面。 This article is a summary of the author’s work practice. The main contents of the introduction is to study the combination of relays, with a small number of relay control a large number of objects, to enhance versatility and flexibility, and to give the memory function, so that used in the production of automatic lines, remote control and display and so on.