The system is mainly composed of MCU (main control unit) that is allocated centrally and DCU (discrete control unit) that is allocated discretely. It takes the power line of 220V or 380V as the medium.

• 它主要由集中配置的中心主控设备（MCU）和分散配置的数字控制单元（DCU）构成,以家庭中的220V（或380V）电力线为传输媒介。