Hey Pods8...wanted to see how your DC-DC charger is holding up? When we switched to our newer truck, the surepower 1314 started cycling due to the voltage drop...I believe the voltage regulator of the alternator in the new truck has a different charge profile then the old truck. We have about 17' of 10 AWG wire from the truck battery to the camper battery and I'm getting about a 1.3 volt drop. Do you know the voltage coming in to your DC-DC charger?...and what gauge wire are you using? Thanks for posting all you mod info!! Cheers.
Seems fine but we unfortunately haven't been out much this winter/spring (been rushing to get some things done around the house prior to the family addition due in late May). When I checked the voltage at the truck bed connection (front driver side of the box) I was getting around 14V if I recall correctly, only .1V drop. I ran 10ga as well.
That 1.3V seems really high, I'd probably inspect the wiring and connections to have sure something isn't screwy, corroded, etc. off the get go. Assuming all is well though that is the nice thing about the DC-DC charger in that it'll take between 10-15V and convert it to the correct voltage. Only downside on feeding it a lower voltage is assuming it regulates to 7.5amps on input you'll have a bit lower output, however if it regulates on output it'll just pull a little more on the input. Some folks may have concern about the 7.5amp charge rate but it works fine for me at this point when I look at how much juice I use verse drive times on trips (I think most folks likely would find that when you really look at truck run time, esp. when working slowly along back country travel). 210amp hours of battery provide a nice buffer in there if by chance I was dry camping and not moving for an extend period of time. On the flip side I never have to worry about a heavy inrush current when the batteries are depleted, I'll get a steady bulk charge.
I have mine wired via an ignition hot remote input as mentioned so it only turns on when I apply power via a switch back to the remote input terminal. I don't run another isolator setup. Doesn't matter what position the switch is in, if the truck isn't running the charger breaks the connection.