Thanks for your reply marininn,
Solar would be nice....where do you carry your two 100 watt panels ? Do you have them mounted to the roof ? And when you say use heavy wire on the truck and trailer what gauge are you talking about ?
I bought some on amazon. Mine are the flexible ones, no frame, no glass, so the panel is just very thin, maybe thickness of two DVDs or less.
I used the tape to secure them on the roof. Just in front of the rear roof vent and behind the AC. They go from one side to the other, this way I was able to avoid the roof seams. I think they cost about $160 each.
I used extension cord. One for each panel and wired them together at the controller. The cord was a 3-wire, so saving the extra wires for a 3rd panel in the future to tend the lift pump battery (I have separate batteries for the camper and the lift). I think it was 14 gauge, but just because the 12 g was so expensive… BUT for the truck and trailer I have wire that the copper is about the size of a ball point pen or bigger. the body of the pen, not the point, lol.
the longer the distance the fatter the wire needs to be. Don't leave a choke point, keep the wire fat the entire way from the alternator to the camper battery. I used a separate plug for the camper charging. It is a 2-pole plug, not unlike the style of the 7-pin you have now. I also grounded the plug on truck and camper side so I dont rely on the ball and hitch for ground, just to keep it clean.
I kept the charging through the 7-pin for the lift pump battery.
However, the 200 watts keep the camper batteries charged, so I rarely ever use the truck to charge them. Only if lots of rain/ no sun situations.
I have a box with 6 switches in it on the truck floor next to gear shifter.
#1 switch is the master to power the solenoid for #2, 4 and 5, its power comes from the fuse box that is powered from the ignition (key off means switch off). It also powers up the running lights on trailer which is actually switched by the truck's lights.
#2 switch powers the 7-pin 12v+
#3 switch powers the camper batteries through a second dedicated solenoid.
#4 switch powers the trailer reverse lights
#5 switch powers the truck reverse lights (because hard to see at night when trucks reverse lights are reflecting off a white camper)
#6 is for DRL (is not powered by #1), (unrelated to the camper).
4 of these switches control 4 relays (running lights, 2 reverse lights and 7-pin charge) which get power from the solenoid connected to #1.
All the 12 volt power for the two solenoids is pulled off the 12 volt positive from the starter motor.
Sounds complicated; seems simple now that I have done it.