Patent attributes
A powering source unit comprising: a first powering source; a second powering source; the first powering source being operable to: apply a plurality of voltages towards a powered device via a first path so as to detect a signature impedance, and in the event the signature impedance is detected, to at least partially classify the power requirements of the powered device by supplying a classification voltage towards the powered device via the first path and measuring the resultant current flow, the classification voltage level being higher than each of the plurality of detection voltage levels; the second powering source being operable to apply at least one voltage towards the powered device via a second path so as to attempt to detect a signature impedance at least partially contemporaneously with the supplied classification voltage of the first powering source.