37' Super C RV Build

[David S]

Starting my RV build. Electrodacus based system, 13kW LiFePo4 build. 50% of batteries have arrived, no solar panels yet. Will update as a I complete steps.

Diagram:


Test Build (remember, it's a TEST build, so things like cable clamps, zip ties, etc... to be added):

 

[apcorob]

I am going to be watching everything you are doing as I will probably copy everything except that I want to depend on victron as I can get parts where I live. Depending on how things work out for you I may copy you exactly. THANK YOU for posting. Your hard work helps me a lot.
Rob

 

[David S]

I am going to be watching everything you are doing as I will probably copy everything except that I want to depend on victron as I can get parts where I live. Depending on how things work out for you I may copy you exactly. THANK YOU for posting. Your hard work helps me a lot.
Rob

I am using Victron extensively (lots of blue in that picture) except for the BMS & solar control. I am currently sourcing solar panels and have additional 280ah cells coming from Michael. When I have the panels, I'll be doing a test setup in the backyard, feeding into my sunroom, where I will be driving a portable ac unit for testing. Once I've burned the system in, I'll move over to installing in the RV. No pressure though :D

 

[Wildfire]

Hi there, I am in Australia doing our RV build. I am interested in why you are using 2 x Multiplus 24|3000's as opposed to a Quattro unit? Cheers, Peter

 

[David S]

Hi there, I am in Australia doing our RV build. I am interested in why you are using 2 x Multiplus 24|3000's as opposed to a Quattro unit? Cheers, Peter

Hi. Two reasons: a) my rig is 50 amp with 2 x 50 amp 120v legs. I intend each leg to be run by 1 inverter. I don’t technically need split phase 240v output to do this but… b) I intend to install a dual zone mini split ac system so I will be running the inverters configured as 180 degrees split phase. Oh and c) Two 3kVA multiplus 24v inverters are less expensive than a single 5kVA Quattro, at least in the US.

 

[Wildfire]

Thanks for the quick reply David, Yes it is the same in Australia with pricing. Cheers, Peter

 

[400bird]

I may have misunderstood the diagram, it looks like your solar panels are wired straight to the battery? No solar charge controller?

Also, why do you have two current shunts?

 

[David S]

I may have misunderstood the diagram, it looks like your solar panels are wired straight to the battery? No solar charge controller?

Also, why do you have two current shunts?

Hi. I am using the Electrodacus SBMS0 bms with Electrodacus DSSR20 charge controllers. https://electrodacus.com/ In this arrangement, I do not need an mppt scc.

 

[400bird]

Sure, no one needs an MPPT, but without power point tracking, you are leaving efficiency (and more PV production on the table)

I hope someone has data for how much more power can be harvested by an MPPT, or even a PWM, charge controller vs direct connection.

Overall, the system looks great. I realize the DSSR20 diagram shows the shunts connected as you have them. I'd prefer both shunts connected to the bus bar, I think it would simplify and clean it up some. But, it's already pretty.

 

[David S]

Sorry, forgot to mention the shunts. There are two because one measures PV input and the other measures overall battery input/output. They are setup like that for a couple of reasons having to do with circuit design. While it’s not as clean (I had them connected to the bus bar directly myself in an early design), it is correct for this type of build. WRT mppt in this design: it has been shown through testing that, for this type of setup with a 24v LiFePO4 battery and properly configured solar panels, an mppt controller brings no extra value/power. LiFePO4 batteries can take the direct voltage,amperage output of 60 cell panels very efficiently.