If like those guys, you’re running your own WISP and need to power Ubiquiti or MikroTik radios, we have always advocated using batteries instead of a UPS as the site will stay up for longer when there is a mains failure. These switches make life much easier as they include within their range of products, PoE switches that can deliver 24v and 48V to radios from as little as a 9V DC supply! We suggest your setup should consist of at least two leisure batteries wired in series, providing 24V or four batteries providing 48V.
Read more about their positive experience with the Netonix switches here.
The full range of Netonix switches and accessories are here.