Embodiments of the present disclosure relate to a primary plugin, a drawer and a distribution panel for a power distribution system. A primary plugin for a power distribution system is provided, the primary plugin comprising: a body; a socket assembly mounted on the body; a measuring unit mounted around the socket assembly and configured to measure electrical parameters in the power distribution system; and a data processing unit mounted on the body and coupled to the measuring unit, the data processing unit being adapted to receive and process the electrical parameters measured by the measuring unit and to upload the processed electrical parameters to a gateway.