Power supply subsystem for powering a node over communication cabling

摘要

A power supply subsystem for providing electrical power to at least node over communication cabling, the power supply subsystem comprising: a management and control unit; a power supply interface for distributing power into the communication cabling substantially without interfering with data communication; and current limiting circuitry controlling current of the power distributed into the communication cabling via the power supply interface, wherein the management and control unit is operative to interrogate the at least one node to which it is intended to transmit power over the communication cabling in order to determine whether the node's characteristics allow it to receive power over the communication cabling.