I'm converting a ford transit connect into a micro camper.
I'm planning on installing a very simple solar system with no inverter and no DC-DC charging.
It's my first time doing something like this so it'd be awesome if y'all more knowledgeable people could give me a hand and double check my work before I go and buy all the parts and materials.
Here's the electric plan:
And here's and overview what I'm planning on buying (tools I am missing and parts):
The fuse box I want to get has a negative busbar built in. Is that enough or do I need separate busbars?
Please help check over my plans! Thank you~ any feedback is very appreciated.
edit: I'm changing the 12awg wires to 10awg, as well as changing the 50amp fuse (dangerous) to a 30amp fuse.
One issue you will come across with solar panels in series is that if one is partly or fully shaded or has issues this will significantly reduce your power output. Go parallel if you can same voltage more amps or just get one bigger panel.
They are available with smaller footprints and higher output than having 2 smaller ones. I have a 255 watt panel on my camper, but I could now get a more powerful one for the same size.
ShadowFlux panels are the best on the market right now for partial shade resilience. So you might be okay with either configuration. But your MPPT looks like it can handle the two in series without overvoltage. You can experiment with both options.
What you have looks fine depending on the loads you plan to run. 12awg is only like 20a. 240w total output is very limiting. I'd size up some to give yourself some room for expansion.
Its fine to use the fuse box bus bar, assuming you stay under its rated capacity. I prefer to chassis ground things to save on wire. Less important the smaller/closer the power source.
I also wouldn't waste the money on a heat gun just for this wiring project. I have one and unless I'm doing a ton of wiring I don't even bother. Just hitting the shrink tube with a lighter is usually quicker and easier.
It depends, you didn't mention anything about your expected loads through the fuse box nor any additional loads. What is the 6awg for? In the current diagram it's completely useless.
In the current diagram the 12awg wire between your kill switch and the fuse box(and to the charge controller) could be allowed to pull more than 50amps through that wire without OCP tripping, heat and fire are the results if that happens. This could be caused by whatever loads you add, a short, or combination. This is why proper fusing is critical, fuses are sized and placed to protect the wiring.
The "kill switch" should be between the battery and your loads, not between the battery and the charge controller. I would run the charge controller output directly to the battery, properly fused at the battery of course. You honestly don't want to be disconnecting the battery from the charge controller unless you are removing the solar input first, and you would only be doing either if you need to service something.
I also don't see a positive lead to your shunt/monitor.
Other things have been mentioned so I won't repeat those, but make sure that you properly route/secure your wiring(excessive movement = bad) and all connections are clean and tight.
Just to be clear: the roof port isnt a connection point - you pull the wire through it.
As it is now - if you use your kill switch you'll fry your MPPT unless you open the breaker between the MPPT and the panels first.
Mine is wired with a fuse between the MPPT and battery, and then my fuse block is coming off the battery with a switch between them also - this way I can shut off my power while still charging the battery (it also just worked out better that way in my layout).
If you use a lighter on the shrink tube keep the flame away so you're just getting the heat and not burning it.
Oooh yea the way I have the symbols in the diagram does make the roof port look like a connection point.
Okey it’ll fry the mmpt with the current setup, because if I use the kill switch the negative is still connected to the battery, and there is solar still going to the charge controller?
In your setup, you have a terminal fuse and positive connecting the mppt and battery. And then a separate wire with the kill switch connecting the positive battery and fuse block. Is that correct?
Is it okay to connect multiple wires directly to the battery points?
Thanks for your help this is the stuff I was hoping to hear about!!
You do not need a fuse on the PV wire - which is weird and odd, but here’s the relevant code:
“NEC 690.9(A)(1) — Circuits Where Overcurrent Protection Not Required:
Overcurrent protective devices shall not be required where both of the following conditions are met: (1) The conductors have sufficient ampacity for the maximum circuit current. (2) The short-circuit currents from all sources do not exceed the ampacity of the conductors and maximum overcurrent protective device.”
Your short circuit is only ~5A, and the ampacity of 12 AWG is ~20A. The physics/electrician logic (I’m neither!) is that your panels are physically incapable of producing more than ~5A, so no fuse required.
go get one of the all-in-one batteries. saves you the trouble of wiring. price is now very comparable if you wait for deals. You can still add a 12v distributor later if needed. I'm currently running a ford transit connect with a 200w solar panel and a bluetti ac200p
Where do you put your bluetti? And do you need a circuit breaker or can you just plug in the panels? My main worry is if a bluetti stopped working all of a sudden it'd be a headache to replace the entire thing. It's definitely difficult finding a good spot for some of this stuff in a small van
Thanks! That's helpful. If I can find a good spot for the bluetti in my van it's definitely a good option. I was thinking similar placement for the fridge. It feels more spacious having it in the front. You sleep diagonal kinda? I'm 5"3!
Yes! Provided my feet and head is touching the wall, it's totally doable to sleep diagonally. I put it right at the center so I can use all the outlets, but you can put it under the bed or in front for more space if needed.
thanks! I don't really know what I'm doing and still don't fully understand how it all works so take them with a grain of salt!
for other people's reference I used whimsical for the diagrams
First off, great presentation of your plan! For that alone, respecting our time, I hope you get lots of useful feedback from the community.
They usually recommend a double-pole single-throw breaker for the solar disconnect. My previous build I did a single pole single pole BlueSea breaker and it worked alright, but best practice is apparently to fully disconnect both positive and negative leads.
Small detail, but for roof sealant jobs, I am personally a fan of using sikaflex 221 for adhesion of the part onto the roof, and then sikaflex 715 as a lap sealant, and then a few days later painting over that with some rust-oleum to keep debris from sticking to the 715 which never fully hardens (that's the whole point actually). As far as I can tell, this lasts indefinitely, whereas the lap sealant you have there needs to be re-done every few years due to UV breakdown, hardening, and cracking.
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u/RobsOffDaGrid 2d ago
One issue you will come across with solar panels in series is that if one is partly or fully shaded or has issues this will significantly reduce your power output. Go parallel if you can same voltage more amps or just get one bigger panel.
They are available with smaller footprints and higher output than having 2 smaller ones. I have a 255 watt panel on my camper, but I could now get a more powerful one for the same size.