Help! Please Review My Wiring Diagram...

[nberna19]

Hi All,

I'm trying to design my electrical system for an off grid camper van. I am a complete newb when it comes to electric so please forgive me. Attached is the first draft of my wiring diagram that I hope you all can make sense of. A few questions I'll propose in advance:

-Coming of my leisure battery I have 4 wires coming off of the negative terminal and 3 coming off of the positive terminal (I may also add an alternator charger in the future which would add 2 more wires). Is this too much coming off the terminals and should I consider wiring it all to a positive and negative busbar beforehand?
-Coming off of the leisure battery, do fuses go before or after an on/off switch?
-I'm not entirely sure of the correct fuses and gauge wire to use on each connection so please look out for this.

Thanks for any and all help,
Nick IMAG0584 (2).jpg

[NCmountainsOffgrid]

normally, RVs of any size only require output of Solar panel wires directly to the House battery bank, NOT to the fuse box...

having said that, if your MPPT controller has a 'direct' load application output, you 'could' use it to power 12v devices/lights/fans directly from the controller - I'm not sure running the output to your fuse panel would be wise, though others with any experience with that can give their own input.

most of the Solar output, going to your battery bank, is offsetting the current Fuse panel usage of your 12v system, so the option to wire it directly there is not really needed - it's already powered by the battery bank, and your solar is 'recharging' the battery bank are you are using the 12v system.

now, as for the Inverter, like the Fuse panel, it draws also from the battery bank.

[SunEagle]

As NCmountainOffgrid mention, having a 40amp fuse box connected to a 30A CC output could overload the CC before you blow that 40A fuse.

You will also need separate fuses for each of the 3 x 100w panels since they are wired in parallel. The one 40amp fuse will protect the #8 awg wire but

[nberna19]

Thanks for all the feedback everyone. I attached an updated diagram w/ a couple changes to note. The solar panels are wired in series, I have the charge controller, 12v fuse box, and inverter connected to positive and negative bus bars before the batteries, and I added several breakers with on/off toggles. The batteries are still wired in parallel. Let me know what you think. Thanks again!

[NCmountainsOffgrid]

while your diagram might work, though it's more detailed than I really know about, my solar wires simply connect directly from the Charge Controller to the battery bank + and - terminals... no need for bus bars, or such.

[neweclipse]

Could connect the batteries diagonally parallel and match or better balance between the two...presently there is one battery favored over the other...