Where to run wires

[FLGuy]

I have a 2023 17MKE with Furrion 25A MTTP charge controller 165W Furrion panel and a lithium compatible converter. I decided to buy a 200Ah lithium battery which of course, is way bigger than my current wet cell battery so I plan to install it under the murphy bed inside the camper where there is a huge wasted space. I am capable of doing the electrical work needed but am unsure of how to get the wires inside the camper. The current setup(factory) has a positive busbar on the A frame that has a 8 gauge wire going to the battery. It appears the same terminal is also connected to the solar output and also goes to the converter. The negative wire from the battery also 8 gauge, got directly from the battery up into the underbelly without connecting to a terminal. I assume this goes to the converter. I tried to get more info from GD customer service but was told "sorry we don't help with any modifications. the factory wiring is the way we think it should be."
My plan is to reroute both of the wires that go to the battery into the camper and under the bed. I know the wisdom of running bigger wires for faster charging etc. We don't really boondock (yet), don't have an inverter and my truck has a built in 7.2KW generator so speed of charging isn't a great concern.. Camper is only 30A service too.
My biggest concern is how to run the wires to where I want them. Do I have to drop part of the underbelly or just drill up into the passthrough and route the wires along the ceiling in there?
Any suggestions would be appreciated.

[ncitro]

FLGuy

I would drop the coroplast to get eyes on it. You should be able to just take some screws out of the front and sides to get access to what you need. I think you will find the negative battery lead just goes to the frame. Otherwise sounds like you are on the right track, move as much as you can up to the batteries, in particular the lead going to the converter and DC distribution panel. Keep in mind those connections on the tongue are self resetting circuit breakers and act as your fuses. If you move the wires you will need to either move them as well or refuse them. I eliminated them from mine and replaced with this fuse panel:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Warning the largest circuits it supports is 30A, I had to split off my bigger DC loads (slide outs and levelers) and fuse them separately.

[FLGuy]

FLGuy

I would drop the coroplast to get eyes on it. You should be able to just take some screws out of the front and sides to get access to what you need. I think you will find the negative battery lead just goes to the frame. Otherwise sounds like you are on the right track, move as much as you can up to the batteries, in particular the lead going to the converter and DC distribution panel. Keep in mind those connections on the tongue are self resetting circuit breakers and act as your fuses. If you move the wires you will need to either move them as well or refuse them. I eliminated them from mine and replaced with this fuse panel:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

Warning the largest circuits it supports is 30A, I had to split off my bigger DC loads (slide outs and levelers) and fuse them separately.

The positive wire that is attached to the terminal on the frame to the battery doesn't have a fuse on it. There are fuses on some of the other wires connected there but not the wire going to the battery. My thought was to just remove the wire from the busbar terminal where it goes to the battery and just replace it with a longer wire into the new battery space under the bed .
Is dropping the coroplast difficult or is it easy as removing the screws holding it up?
Thanks

[ncitro]

The positive wire that is attached to the terminal on the frame to the battery doesn't have a fuse on it. There are fuses on some of the other wires connected there but not the wire going to the battery. My thought was to just remove the wire from the busbar terminal where it goes to the battery and just replace it with a longer wire into the new battery space under the bed .
Is dropping the coroplast difficult or is it easy as removing the screws holding it up?
Thanks

Just remove the screws and it should come right down. That would work, but adding length to the run from the converter will hurt your charge rate. I know you said you are not worried about that now, but it is something to keep in mind for future planning.

[FLGuy]

Just remove the screws and it should come right down. That would work, but adding length to the run from the converter will hurt your charge rate. I know you said you are not worried about that now, but it is something to keep in mind for future planning.

Thanks. I think the straight run from the terminal to the battery would be about 4-5 ft max. The current lead is just over 2 ft so not much difference there. Right now I don't want to pump any more money into something I don't need right now. I know the solar I have won't keep up with my 12V fridge usage if I try to boondock more than one night, but the generator on the truck can charge up the battery pretty quickly for now if needed. If I need 120 for anything the truck can power the entire camper including the AC only using a half of possible output. Possible future upgrades coming a we camp more.