N2K power question

[Jerry Woodward]

I just bought a Zeus 2 9", Vesper XB8000, and a BG 508 wind sensor with 20M of N2K cable. I plan to run the backbone down the mast and have drop cables to the Zeus and Vesper as well as a power cable, pretty straightforward. My confusion is that both the Zeus and Vesper have an independent power connection separate from the N2K connection. I thought that the devices were supposed to get their power from the N2K network. Are those other power connections only needed if you don't have an N2K hook up?