An Ethernet-compatible powered device (300, 400, 530, 640, 720, 808, 930) classified as an Ethernet powered device and operable between: an Ethernet Power Source Equipment (610, 700, 800, 910, 920), PSE, and an Ethernet Powered Device (750, 940), PD, comprising a 25kΩ signature resistance, wherein the device is configured to be coupled to the PSE and the PD by at least two respective pairs of Ethernet cable conductors; the device (300, 400, 530, 640, 720, 808, 930) including: voltage-threshold detection circuitry (310, 440) disposed between a return rail (325, 411) and a negative rail (330, 412), each rail being coupled to a respective pair of the Ethernet cable conductors coupling the device to the PSE and the PD; a load (320, 540, 644, 930) coupled inline with a switch between the return rail (325, 411) and the negative rail (330, 412), the switch being in operative communication with the voltage-threshold detection circuitry; and the voltage-threshold detection circuitry and switch being configured to: allow the load (320, 540, 644, 930) to source current from the respective pairs of the Ethernet cable conductors when the voltage sensed by the voltage-threshold detection circuitry is below a predetermined threshold, said device being configured to draw an amount of DC current in one or more voltage ranges outside the ranges specified by the IEEE 802.3af standard for detection and classification, and the value of the DC current drawn within said voltage ranges acting as additional signature and classification values for said device; and place the load in a high impedance state where the load is isolated from the PSE, when the sensed voltage exceeds the predetermined threshold, said device being configured to allow the PSE to discover the 25kΩ signature resistance presented by the PD; the device being configured to provide a common mode signature that coexists with the 25kΩ signature resistance of the PD connected to said device. an Ethernet Power Source Equipment (610, 700, 800, 910, 920), PSE, and an Ethernet Powered Device (750, 940), PD, comprising a 25kΩ signature resistance, voltage-threshold detection circuitry (310, 440) disposed between a return rail (325, 411) and a negative rail (330, 412), each rail being coupled to a respective pair of the Ethernet cable conductors coupling the device to the PSE and the PD; a load (320, 540, 644, 930) coupled inline with a switch between the return rail (325, 411) and the negative rail (330, 412), the switch being in operative communication with the voltage-threshold detection circuitry; and the voltage-threshold detection circuitry and switch being configured to: allow the load (320, 540, 644, 930) to source current from the respective pairs of the Ethernet cable conductors when the voltage sensed by the voltage-threshold detection circuitry is below a predetermined threshold, said device being configured to draw an amount of DC current in one or more voltage ranges outside the ranges specified by the IEEE 802.3af standard for detection and classification, and the value of the DC current drawn within said voltage ranges acting as additional signature and classification values for said device; and place the load in a high impedance state where the load is isolated from the PSE, when the sensed voltage exceeds the predetermined threshold, said device being configured to allow the PSE to discover the 25kΩ signature resistance presented by the PD; allow the load (320, 540, 644, 930) to source current from the respective pairs of the Ethernet cable conductors when the voltage sensed by the voltage-threshold detection circuitry is below a predetermined threshold, said device being configured to draw an amount of DC current in one or more voltage ranges outside the ranges specified by the IEEE 802.3af standard for detection and classification, and the value of the DC current drawn within said voltage ranges acting as additional signature and classification values for said device; and place the load in a high impedance state where the load is isolated from the PSE, when the sensed voltage exceeds the predetermined threshold, said device being configured to allow the PSE to discover the 25kΩ signature resistance presented by the PD; the device being configured to provide a common mode signature that coexists with the 25kΩ signature resistance of the PD connected to said device.