This disclosure describes techniques for automatically identifying endpoint devices based on differing power loads drawn by the endpoint devices. In some instances, the endpoint devices are distributed about one or more facilities, such as item handling facilities, and may comprise an array of sensors for tracking inventory items within, into, and out of these facilities. These sensors may include cameras, weight sensors, RFID readers, microphones, and the like. Further, multiple ones of these sensors may couple to a power injector (e.g., a power-over-Ethernet (POE) injector) that provides both data and power to each sensor over a cable. The power injector may in turn couple to a network switch and/or a controller, which may identify the endpoint devices based on their modulated power loads.