Power over Ethernet (PoE) describes standardized systems which pass electrical power and data along twisted pair Ethernet cabling. PoE-enabled devises allow for a single connection that provides both data connection and electrical power, instead of the traditional power connection and separate network connection.
Components of PoE systems
Complications with PoE Powered Devices and Power Sourcing Equipment (PSE)
A common issue experienced by users revolves around the complications with PoE powered devices and PSE. It is first important to understand that there are several standards for injecting power: two sub-standards associated with 10 Base T and 100 Base TX being IEEE 802.3af Alternative A and Alternative B.
The Original PoE standard and PoE+
Considerations For Solar
Although PoE injectors can provide up to 30W per channel, that does not mean the device is consuming 30W. The solar system should be sized based upon the device consumption and any losses or inefficiency of the injector itself. Typical PoE injectors have a 24VDC or 48VDC input; selecting an injector with a wide voltage input will eliminate the need for an additional DC/DC converter. Additionally, using a switch with a built-in injector might be more efficient than using separate devices.