PLC sub-controller and control system

The embodiment of the invention provides a PLC sub-controller and a control system, and the PLC sub-controller comprises a first PLC module which is used for being connected with a first power line; a second PLC module which is used for being connected with a second power line; and a serial port module which is connected with the first PLC module and the second PLC module that communicate with each other through the serial port module. According to the invention, the time delay of a communication message is reduced, and the message sending success rate is improved. 本申请实施例提供一种PLC分控器及控制系统，所述PLC分控器包括：第一PLC模块，所述第一PLC模块用于连接第一电力线；第二PLC模块，所述第二PLC模块用于连接第二电力线；串口模块，所述串口模块分别连接所述第一PLC模块和所述第二PLC模块，所述第一PLC模块和所述第二PLC模块之间通过所述串口模块进行通信。本申请实现了减少通信报文时延，提升报文发送成功率。