We recently acquired a year-old 6x12x7h, single axle, CTC..but the trailer type doesn't matter for my questions.
I've been doing a TON of research primarily here on tnttt on all facets of building up and powering a camping trailer. This place is such a treasure-trove of info..you folks are great.
With respect to electrics, both 12Vdc & 120Vac..
120Vac: The trailer has a 50A service installed(previous owner, Wells Cargo install) and has 120V plugs installed inside, as well as 120V lights & AC/Heater.
12Vdc: No 12Vdc is available yet inside the trailer, however it is wired for 12V LED lights in the ceiling (Wells Cargo factory install, powered/wired through trailer pigtail running lights)
I'll be building cabinetry in the v-nose of the trailer, but have a concern about excessive tongue weight if I add battery(s) and a high efficiency chest refridge (truckfridge, engel, arb, dometic..etc..) to the v-nose area. I haven't determined the curb and tongue weight yet..but let's shelve that discussion for the moment.
Now my questions.
1) Has anyone run their trailer off a 12V umbilical from the tow vehicle? I'm thinking of having the 12V fridge, battery(s), batt charger, and solar controller in the back of the tow vehicle and then running a heavy gauge 12V extension cord to the trailer. Maybe a 20 foot cord. I'm aware DC power is subject to voltage drops. The cable would be sized accordingly. I'll probably be using a 100W suitcase solar setup to charge the batts.
Trailer 12V loads would be a ceiling vent-fan(7 hrs at night, probably a low-draw computer-server fan), minimal LED lighting for less than a hour a day, and charging phones(primarily), occasional topping off a laptop battery...that's about it. We're long-term tent campers and don't use much power in primitive campsites.
2) When we do camp at a site with 120V power (probably 1 in 5 or 10 trips) I'd plug into 120V power and have a 12V converter inside the trailer for all the 12V loads. The fridge, batts, batt charger, and solar controller would still be located in the truck.
Seem reasonable?
I'm thinking having the main 12V load, the fridge, and batts in the tow vehicle solves any potential tongue weight issues and allows easy vehicle charging of the (AGM)batts when we make a run in the truck somewhere as well as charging the (AGM)batts and running the fridge while were traveling during a trip. The suitcase solar panels can be plugged into the controller in the vehicle. I'd probably build some sort of power-station box for the truck to hold all the components. The back hatch of the truck is always open when we camp.