are you talking to me?
its set so that when on a campsite i can plug into the mains, which i can then use to power normal 240 stuff, the 240 is also wired into a an inverter which will convert to 12v dc, this i can use for the leds, and stereo without draining the battery. the switch is automatic and instananous so the radio doesnt notice the switch and doesnt need restting and i can run boththe leds and stereo for as long as i want and just drive of in tho morning, or a month later for that matter.
i get theres power wasted in the inversion, but who cares? it comes from the grid anyway and doesnt cost me more if i use more?
when i camp where theres no power i can just use the whole setup from the battery with no modifications, to me this seems a better way of doing it then simply running it from the battery and having to recharge the battery, also the leds are remote contro, and the remote sensor draws power even when the lights are off, so if i wire it just to the batery it will draiin the battery unless i switch all the lights off and the remote sensor. running via the invrter this way i can turn on a zone with the switches shown, say the floor in case i want to take a piss in the night without waking everyone then turn the lights off with the remote, when i wake up in the night ihit the remote and only the floor lights are turned on, maybe with a low intensity also if i wish.
maybe im missing something or maybe you didnt know enough about the circuit but i cant think of a better way of doing this,
stu