人机界面只能连接PLC吗？ 不是这样的。
Can man-machine interface only connect to PLC? That's not the truth.
人机界面产品是为了解决PLC的人机交互问题而产生的，但随着计算机技术和数字电路技术的发展，很多工业控制设备都具备了串口通讯能力，所以只要有串口通讯能力的工业控制设备，如变频器、直流调速器、温控仪表、数采模块等都可以连接人机界面产品，来实现人机交互功能。
Human-computer interface products are produced to solve the problem of human-computer interaction in PLC. However, with the development of computer technology and digital circuit technology, many industrial control equipments have the ability of serial communication, so as long as industrial control equipments with the ability of serial communication, such as frequency converter, DC governor, temperature control instrument, data acquisition module, can connect the human-computer interface products. Human-computer interaction function.