Me thinks that by starting out with the PD-4045 you have about 95% of the "Design" issues already behind you. With that box the following issues are already designed in....
1. AC Distribution. Proves a main breaker, a breaker for the converter, a breaker or two for AC circuits and one for the air conditioner if you have one and you are good to go. You will want to use "Dual" package breakers that have two breakers in one to save space. I'd start out by using an "RV" rated shore power cord of either 20 or 30 amps.
2. DC Distribution: You have about 12 fused circuits to go crazy with. You can
a. Fuse the lights
into two or more groups so, if you blow one fuse there are still lights on. Separate the inside from the outside light(s)
b. Fuse the water pump
c. Fuse the Furnace
d. Fuse each of the DC outlets you install separately, same reason as #1.
e. Fuse any exhaust fans independently from the lights
f. Fuse Any other special DC accessories and you still have a bunch of fuse lines left for future use.
TIP#1 >>>>> Write down what each fuse goes to as you wire them, it's very easy to forget what goes where.
TIP #2 >>>>> If you use any common ground wires, be sure it is big enough to carry all the loads that will be riding thereupon. I personally run two wires to everything and set up a common ground buss external to the PD 4050.
The internal circuitry on the PD-4045 makes the battery
connection very easy. Connect the + side of the battery
to the input buss with at least a #10 wire, use #8 if the run is from the tongue. I put a 30 or a 50 amp breaker in that line. You connect the charging line from the TV directly to the + side of the battery as well'
Connect a digital battery monitor at the battery. VoltMinders are great if you can get one.
Connect the (-) side of the battery to the (-) buss in the PD-4045 as well as to the external ground buss mentioned above. Be sure to also connect to the frame so the charging line from the TV will work.
Now all you have to do is identify what are called standard wiring practices, buy a ton of wire, wire clamps, zip ties and terminals of all sorts (only use the kind you crimp with a pressure crimper, (not a $1.98 pliers crimper) and you are in business.
Except for the AC side, where I use romex type products, I don't go crazy on color coding,, it gets to expensive, but I also tag all of my wires at each end with a little zip-tie flag.
Also, never bundle AC and DC wires in the same bundle. Some of our newer electronics don't care for any AC leakage into the DC lines that might occur.
Nuff for now.....
Be sure to add more questions......