Power distribution units, power distribution systems, and related methods for controlling relay switches of electrical cords are disclosed herein. According to an aspect, a PDU includes multiple electrical plug receptacles for operatively connecting to one or more electrical cords for providing power to the electrical cord(s) to transmit power to connected electronic devices. The electrical cord(s) each include a switching relay configured to control transmission of power via the respective electrical cord. The switching relay is configured to receive a control signal for controlling the transmission of power. The PDU includes a connector to a power source configured to supply power to the electrical plug receptacles. Further, the PDU includes a communications module configured to individually route control signals to the switching relays for individually controlling transmission of power via the respective electrical cord(s).