A powerline communication control system for controlling a lighting unit, such as an LED lighting unit, including a master controller for receiving lighting unit control inputs from a lighting controller and generating corresponding lighting unit command outputs in a lighting system command format and transmission mode and superimposing the lighting unit command outputs onto the power distribution system and at least one lighting slave unit for receiving the lighting command signal, separating the lighting command signal from the power signal and for providing lighting unit control commands to the at least one lighting unit to control illumination thereof.