Power sourcing equipment providing a plurality of power sources for
connection over communication cabling to a single powered device, the
power sourcing equipment comprising: a first power source; a second power
source; a control circuit; a current sensor adapted to monitor an output
current of the first power source, the current sensor being operatively
connected to the control circuit; and a voltage regulating means
associated with one of the first power source and the second power
source, the voltage regulating means being responsive to the control
circuit, the control circuit being operative responsive to the monitored
output current to operate the voltage regulating means so as to maintain
the monitored output current within a pre-determined range.