The Power of PoE
By Bryan Harris, PE, RCDD
Even if you are involved in voice and data system design or operation, you may not have heard of PoE, or power over Ethernet. Standards-based PoE dates to the early 2000s as a method for powering electronic devices over the same cable that carries voice and/or data signals. Digital telephones, which previously required a separate transformer that plugged into a standard wall outlet, were some of the first devices to take advantage of this technology. It eliminated the need for a separate device and wiring to power the phone. And, since the PoE power is fed from the same data closet switch that carries the voice and data, providing redundant power for the phone was simplified.
Since its initial inception, many devices have been added to the list of electronics than can be powered via PoE. Some of these include IP cameras, wireless access points, IP television decoders, public address systems, time-sync wall clocks and point-of-sale kiosks. In all these examples, the device is primarily a voice/data device that also receives its necessary power from the data wiring.
As PoE has developed, the amount of power available for distribution to devices has increased significantly. Original PoE implementations allowed only about 13 watts. Current standards, though, now allow power up to 71 watts, with the most recent standards approaching 90 – 100 watts.
With the advent of low-power, non-voice data devices such as LED lighting, PoE has the capability of being used for low-power electrical distribution. In some cases, there are significant cost savings with a low-power distribution infrastructure, as compared to typical AC electrical distribution. This type of design is already gaining significant use in the hospitality and retail industries. As the technology grows, office environments and locations with significant IoT (Internet of Things) applications will adopt this technology for its energy efficiency and connectivity integration.
For further information, contact Bryan Harris at 330-526-2716 or firstname.lastname@example.org.