Power over Ethernet
From SpinetiX Support Wiki
Introduction
Power over Ethernet (PoE) is a standardized method of providing DC power over the unused wires in Cat5/6 cabling. It is commonly used to avoid the need for an external power supply.

A standards' compliant PoE switch will check for a resistive signature to determine if the equipment at the other end supports PoE before initiating the power sequence.

Be aware of devices called “PoE injectors”, most of which are of the non-standard “passive” injector kind, that do not check if the equipment connected to it actually supports PoE and therefore have the potential to create damage on a player that does not support PoE. Such damage will void the player's warranty.
Native support
External assistance
If you need to use PoE with players other than HMP400/W, which don't have support for it, you can employ a separate PoE splitter, which sits between the network cable and the player, and transfers the power onto a standard DC jack which is plugged into the player.
PoE splitter
The PoE splitter must meet these specifications:
PoE splitter products can be found on Internet, such as this one: Level One POS-3000 PoE Splitter (this product has not been tested by SpinetiX).