Patent ID: 8086878

Claim:
A method of powering a plurality of remote devices from a power sourcing apparatus that connects to each of the plurality of remote devices through a respective cable connecting the power sourcing apparatus to the remote device, the method comprising: (A) providing a minimal power to the remote device for operation in a low power, startup state, the minimal power provided to the remote device effective (i) to perform a voltage measurement and (ii) to send a signal to the power sourcing apparatus; (B) processing a signal received from the remote device, the signal including values of a maximum expected power demand for the remote device and a voltage measurement made by the remote device at an end of the respective cable adjacent to the remote device, the value of the voltage measurement at the end of the respective cable adjacent to the remote device being indicative of a power loss in the respective cable, the power loss in the respective cable and the maximum expected power demand for the remote device forming a basis for a value of a predicted total power demand for the remote device when the remote device is operating in a normal operating state; (C) if the power sourcing apparatus has enough spare power to supply the predicted total power demand, allocating an amount of power equal to the predicted total power demand to the remote device; (D) with the remote device operating in the normal operating state, performing actual measurements of voltage, power consumption and current to produce a value of an actual total power demand of the remote device, the power sourcing apparatus allocating another amount of power equal to the value of the actual power demand to the remote device; and (E) if the power sourcing apparatus does not have enough spare power to supply the predicted total power demand, rejecting an allocation of power to the remote device.