The inverter is hooked up to your battery (or a spare), correct? If so, why not 'cut' one of the wires from the battery to the inverter, and use a relay tripped by your acc/ign wires. Works for turning it on/off when your vehicle is on/off. You would just always leave the inverter turned on, but power would be cut or applied via your ign state. Shutting down a system is another story though...
If your trying to find some "smart" shutdown procedure without using a dc/dc psu, well, I have no idea where that would come from. Via lack of sleep, I can only think of getting a dc/dc psu and not really use it, but use the turn off feature. Would require more relays and splicing into the mobo on/off headers for those relays. Doubt you want much wiring at this point though
Because I was worried that there would be to much pull that it would blow the relay. Also want it to automate. When it shuts down, I need it to 100% shut down. Also because my systems eat a lot of power, I need everything to shut off for hybrid sleep for the main PC system. The uSDC is a smart controller. I emailed the creator and he says my setup will work. <crossing fingers>
HiJackX1 UAMCB w/ The Tobiathin Core Android/Win 7 hybrid system!
4x 10inch Tablet
1x Win 7 / Rear Entertainment PC
ft/ Web Server Streaming