| 摘要 |
Measuring the resistance of conductors within data cables over which power is supplied, where equipment connected at the remote end presents a DC short circuit. The invention has particular application in determining power loss in Power over Ethernet (PoE) systems, wherein Power Sourcing Equipment (PSE) delivers power to Powered Devices (PD). The invention is concerned with accurately determining the cable resistance, and thus power loss, in order for a PSE to supply more of its power budget to a PD when required. Apparatus according to the invention may be incorporated within PSE or PD. The DC short circuit may be presented by transformers in the PoE apparatus. |
