The centralized controller (centralizer) is located between the client (or cloud server) and the light controller, and is responsible for managing all the single light controllers under a transformer station, communicating with the client (or cloud server) upward via GPRS and downward via power line PLC (OFDM). The concentrator adopts an operating system model with a variety of built-in applications, providing a rich set of software features that allow it to work independently of the client (or cloud server).