I have found, with Apex Fusion power notifications, when power dies I get an e-mail and text. I think it's constantly pinging and if it doesn't reply, it sends you notification. Could be a false positive, but nonetheless, good. I have an Apex on one of my systems with no battery backup and just last night, got the notice. My other system, with battery backups, I didn't because it was still replying (my router is on a backup as well).