POH: The Power Behind HDBaseT
Recently Fluke Networks posted a blog about HDBaseT that explained the application and how testing isn't really any different since standards-based Category 5e, 5 or 6A will support it. But maybe you've also heard about power over HDBaseT, or POH, and you're wondering how that differs from power over Ethernet (PoE).
An overview of HDBaseT and review of the evolution of power over Ethernet standards - HERE
A Little Bit More
Based on and backwards compatible with the IEEE 802.3at PoE Plus standard, POH delivers up to 100W of DC power over four pairs of Ethernet cable in conjunction with video signals to a distance of up to 100 meters (m) -- enough to power a typical LED TV. In fact, Energy Star™ 6.1 restricts all TVs 60 inches or less to no more than 100W and that wattage is dropping.
POH technology opens the door for a cost-effective, easy way to deliver power to digital signage in airports, hotels, hospitals, cafeterias or any other environment in need of a video display--eliminating the need for AC power. This is especially appealing for applications near water where AC power presents a safety hazard. As you can imagine, customers across every market are therefore starting to demand POH.
One key difference compared to PoE is that instead of the powered device assuming worst-case cabling, POH allows the device itself to identify the cable length and draw more power as long as it does not exceed the 100W. That's pretty much where the difference ends (other than the capital "O" in the acronym).