Building a beginner systems for my on/off road and on/offgrid camper

[tehdutchie]

Hi Guys,

Im in the process of starting to collect bids and bops for our 4x4 camper truck.

I have some nice 280ah cells on the way from China and plan to built a 24v system (the truck is 24v and this also means I can use thinner wires).

The following is what I am thinking about and considering;
- 8x 280ah cells
- need a BMS with low temp cut off, considering Chargery 8ST
- Relays need to isolate the batteries I think (what size in 24v? Can I use the 12v versions?)
- MPTT needed for cells solar, size I have no idea, what would be need in solar to charges these sells during the duy? lets say from 50% back to 100%?
- Dc/Dc unit to fo from the alternator to the batteries (need a relay too?)
- Inverter 3000w (?) 24v to 220v
- Been looking at Victron Cerbo and Touch 50 GX to maintain and check it all
- Shore to battery charger, 220/110 to 24v
- Might also want to charge the 2x 12v (24v) truck batteries with all the systems.

Mostly trying to find help in sizing components based on the 8x 280ah batteries, we plan to runs most items in the truck at 24v and dont have much power usage beside the odd cup of coffee (from a nespresso or a 850w 220v coffee maker) and laptop chargers.

Any help with sizing the right amount of solar, mptt controller etc would be appreciated

 

[Ryang]

I’ve actually ordered an all in inverter ac and mppt unit. Keeps costs way down and reduces wiring etc. 3000w and running the same batteries as you. Might be an option your keen on.

Sizing really depends on use which I’m guessing you don’t know. Main draw is fridges, cooking , heating, cooling etc. are you using gas or electrics?

Btw, love the truck. Be sweet when she’s finished.

 

[tehdutchie]

Thanks @Ryang ! Coming weeks are all around sanding, filling, sanding, filling, sanding and then some paint!

We will cook on gas, heat with diesel (water and air) so those parts are sorted. Main usage will be the fridge(24v), led lights and charging of laptops and batteries for camera's etc.

What unit did you go for and what bms did you end up selecting?

 

[tehdutchie]

Got my 280ah cells in plus the 24v overkill solar bms! Time to start buiilding I'd say!

 

[Luthj]

I am assuming your going to top balance before assembly?

Also, nice truck.

 

[tehdutchie]

Still need to unpack . <= so yes

 

[mckennab]

Jeez - that trucks's a beast!

I'm in a similar situation as you with batteries ordered but thinking about the other components. I think I'll be able to squeeze 1600W of solar onto my 16'x7' trailer (not yet acquired ) I want a really efficient system to maximize off-grid use. I'm looking at something like this but with the diy batteries: https://www.mobile-solarpower.com/4000-watt-24v-solar-system.html.

 

[tehdutchie]

@mckennab how did you size the solar panels? This I mostly wonder. Is it just use as many as you can?

(added some paint )

 

[mckennab]

@mckennab how did you size the solar panels? This I mostly wonder. Is it just use as many as you can?

(added some paint )

Wow that truck looks amazing! So jealous.

Basically yes, squeeze as many as possible onto my footprint of 192" x 84" - the renology 100W allow me to fit a 4x4 array. All the advice I've ever read say to over panel as much as possible.

 

[tehdutchie]

Thx again! Doing it on a seriously small budget (the camper built) but good progress

Thanks for the headsup! All 12v panels? Series or parallel?

 

[mckennab]

Thx again! Doing it on a seriously small budget (the camper built) but good progress

Thanks for the headsup! All 12v panels? Series or parallel?

Yes 12V, 4S4P (or 4P4S - I can never remember which way round they go)