I picked up a Konnected Alarm panel pro for my 2005 build house with a DSC wired system. It has 2 keypads and I would like to replace those with wall mounted tablets in a Home Assistant configuration The keypads are 12v DC but the tablets are 5v dc. So I bought 2 step down converts with my Konnected Alarm Pro. I would like to take the DSC alarm panel totally out of the mix so I was wondering if using a 110v AC to 12v DC power converter chained together with a Shelly One Relay before the 12v to 5v converter would be safe. The Shelly is to cut power to the 12v supply when the tablet is between 15% and 95% battery.