Can Anyone Check My Layout please

[Virtualmeuk]

Hi Folks,

Just about to replace all of my old CBE Kit and go with a lithium setup. I think i have set out this layout correctly with regards wiring etc but i am unsure on wire sizes, fuse sizes and would like to get an idea if i am on the right track with it all before i get to far down the wrong road. I want to stick with victron kit at this stage so i can see all of the relevant info on the touch 50 but am open to suggestions.

If anyone can offer an opinion, advice, suggestions for a simpler or cheaper alternative, wire sizes, and fuse sizes i would appreciate it.

 

[Virtualmeuk]

Anyone?

 

[TeeCeeJay]

I think you need a fuse and or isolation between the solar panel and the MPPT. And also some fuses at each of your batteries.

Have you read through the how I done it guides from @Dellmassive there is loads of info on how to size your wires and fuses in there

 

[Salty Spuds]

Anyone?

Initial thoughts are, too many bells & whistles, not enough solar & DC-DC to keep up with that humongous battery.

 

[Virtualmeuk]

Interesting. Which bits are 'Bells and Whistles'? Would be good to trim it back a bit. What dc-dc or battery size would you suggest?

 

[TeeCeeJay]

In this video at about 3:40 Greg goes through how to calculate the size of battery you'll need.

If you haven't already done it, you'll need to know what you want to power, how long you want to power it for and how much juice each item will use. Will you be off grid for weeks or using EHU every day at a site?

For reference, we've got a fridge that we never turn off, some lights and a couple of USB plugs. No inverter or heater. A 200W solar panel and a 100ah lithium battery, we don't have EHU and managed 14 days on tour in Scotland without ever going lower than about 60% on the battery. Our DC-DC handles solar and tops up the starter battery when the LB is full.

 

[TeeCeeJay]

 

[Salty Spuds]

Interesting. Which bits are 'Bells and Whistles'? Would be good to trim it back a bit. What dc-dc or battery size would you suggest?

As big a fan as I am of Victron kit, do you really need the Lynx, Cerbo, Smart shunt, battery protect, GX touch etc. If the Roamer has Bluetooth & a half decent BMS, all these things can be monitored & performed by the built in BMS. All the other gubbins might be handy in a multi battery setup, but (IMHO) it's way overkill for what is essentially a very simple run of the mill camper setup. Do you have a specific need for the inverter? It isn't a particularly big one & isn't going to run anything meaningful, so unless you have a specific need for a low power 240V supply, you could drop that too. The Orion TR has now been superseded by the 50A XS. I'd also be looking at using some of the savings on a 200W solar setup.
Just my 2 penneth

 

[ginkster]

I’d start at the basics, what is it you want/need to power , how often and where? Once you know that you can design the system to do what’s needed. At present it appears to be massive overkill in some areas (multiplus, Cerbo) and very under speced in others (solar). If you want off-grid then solar is king. If you are exclusively on hookup then you don’t need any and a smaller battery would suffice.

 

[Virtualmeuk]

Thanks for the honest replies. Maybe i need to have a rethink...

The Cerbo and touch i already have as they were gifted to me by a friend.
The lynx was just because the rest of the system is Victron so thats the research route i went down so i will look for alternatives if its not needed.
The smart shunt i already have for my current setup and the battery protect i thought was the 'right thing to do' but if its overkill i will drop that as well.
The inverter was just that if im going the whole hog i might as well future proof it for charging laptops and just i case i ever need it.
The Solar i already have on the van with the MPPT.
The battery again was just that if im going to change it all from AGM battery setup to Lithium i might as well do it properly.

The plan is for the Van to be able to support us for a minimum of a few days up to a couple of weeks touring round and wild camping with the occasional pitch if we can find one but without the need to find a pitch with hookup so we have more options.

Thanks again for the useful comments. Ill go away and do some more research.

 

[TeeCeeJay]

Don't forget that if switching to LiFePo4 battery you can use almost 100% of the battery capacity compared to only about 50% of the AGM capacity. Your planned 230ah roamer battery will give you 4x the useable power of a 100ah AGM. To be honest, we could probably survive on a 50 or 75ah lithium battery.

 

[Salty Spuds]

Don't forget that if switching to LiFePo4 battery you can use almost 100% of the battery capacity compared to only about 50% of the AGM capacity. Your planned 230ah roamer battery will give you 4x the useable power of a 100ah AGM. To be honest, we could probably survive on a 50 or 75ah lithium battery.

I’ve had a look at the specs of the roamer range & unless I’m missing something, they have poor low temperature performance. No in built heater & they lockout charging at 0deg, which for some, might not be an issue, but for those that use their vans all year round, it could be a significant problem. It would be a deal breaker for us.

 

[Stay Frosty]

They lock out the charging at 0 C but still supply power and you would have to be consistently below zero not to be able to get some electric back in while you use up that 230Ah worth of power.
Back to the schematic and it looks way over complex, mine was a fag packet type design/ install and definitely KISS but has the Roamer 230Ah battery, a Renogy DCC50S, two Renogy 175w panels, 2kw Renogy inverter, Sargent ec160 (came with the Redline conversion) and a Renogy 500A shunt with display so I have an idea what's going in and out of the battery.
With a 300A battery isolator and a mixture of maxi and mega fuses it's a simple and rugged setup with minimal wuckfittery.

Free electric, but this was June not mid Winter.

 

[Virtualmeuk]

OK So i have taken everyones views and opinions on board and made a few changed to the components and spec etc and i have added wire sizes and fuse sizes.

I have kept the inverter because i actually had a need for it a few weeks ago when i made the Van into a mobile office for a couple of days when i was doing a particculaly dificult survey that was easier to measure and draw on site rather than back at the office and had to borrow a jackery to power my laptop (240w) for the day.

The Fuse / Dis Block is a 4 way for 20 quid and i have got a new 200w renogy one to replace the old one and a new MPPT.

Any opinions Now?

 

[TallPaul_S]

From your original set up I was going to say that a bigger solar panel would be a good idea, and the newer Orion 50a DC-DC. So all good in that respect!

I did 3 weeks in the van a month or 2 ago and didn't need hookup at all. That was with a good amount of cooking on an 800w induction hob, too. But, when I had no solar (shades campsite) I was very quickly down to below 50% SOC after 3 or 4 days with no induction cooking.

I have a similar set up:

Fogstar 230Ah seat base battery
Victron Orion XS 50a DC-DC
Victron MPPT 100/20
Victron 305w rigid solar panel
Victron smart shunt
2000w Renogy inverter
Victron Cerbo GX
Victron Touch 50

I love the Cerbo GX, and the touch 50 is the icing on the cake. With VRM and a 4g connection in the van, you can do so much more than with the std Bluetooth monitoring.




On your diagram - your cable sizing needs some work. In general the sizes are either way over specced, or just mismatched.

You've got 25mm² as the cables from the solar panel to the MPPT. You won't fit 25mm² in the MPPT, ignoring the fact that it's way oversize. PV cable will be either 4mm² or 6mm². Use the same size from the panel to the MPPT and from the MPPT to your main fused distribution board.

Inverter wiring: you've got 50mm² from the distro board to the inverter, yet 35mm² from the battery to the distro board. That makes no sense. Use 35mm² for both runs, as per Victron recommended sizing.

On the main feed from the 12v fuse box, again you're using 25mm² which is rated for 170a - on a fuse box that will only ever see 80a if you have everything turned on at once.

Of course you can over spec your wiring but it'll end up costing loads more and it's harder to work with.

Edit: you've got some other major errors too, like a 60a fuse for the inverter, which should be a 200a.

 

[Virtualmeuk]

Thanks for the reply.
The cable sizes are just from using a few different online Calculators but they all seem to have different results so I've upped them a size to be safe. Does anyone know of a more reliable one?
Most of the info on the Solar was 4 or 6 AWG so i think i may have misread the chart. Ill have another look into it.
Yeah i spotted the Inverter fuse after i posted it. I've changed it.
Is it possible to have 2 12v Dist blocks so that i can use thinner cables and smaller fuses like 2 200amp fuses instead of 1 400 amp?

 

[TallPaul_S]

Ah yes, the old AWG vs mm2. The american system (American Wire Gauge) just makes no sense!!

I use this from 12v planet as a good guide: Cable Sizes