Van build for diversity


We have a new to us Chevrolet Express Van. I have built several 12V DC based campers utilizing solar in the past two years. For the van, I will be using (already using) a 105ah AGM battery wired into a Blue Sea Fuse Block which will power non-essential (at least what I consider non-essential) 12 volt needs. (Roof Fan, lights, water pump and charging phones) For our critical needs, the EB70 will power our Engel 12V Compressor Fridge. I currently have a 200 watt Renogy Solar Panel on the roof that feeds a Renogy MPPT and then our single AGM battery. I will build the connections so that I can either feed the solar to the EB70 or to the Renogy MPPT depending on my needs. I will be able to charge the EB70 from Solar, AGM battery, van power or shore power. I will be able to switch between the AGM battery and the EB70 depending on each units charge level as needed. I know it sounds a bit convoluted but I spent 35 years wiring and working with large DC V telco systems and battery plants and it was all about diversity and redundancy. Guess it carries over to my van.

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Excellent to have you around @SierraVanCampers ! That sounds pretty similar to my little camper build out plans. I have a 2000 13’ Scamp and as I DEFINITELY don’t have the experience as you do with all this, haha I am learning day by day and loving every second of it!!

When I first got it, March 2020, I had NO real knowledge of what I was doing, but after some research, I “upgraded” the scamps house batteries to 2x85ah vmaxx AGM batteries. Kind of wish I would’ve waited on pulling that trigger as I would’ve went with lifepo4 batteries now, but like I said, I didn’t know what I was doing and wanted to just “upgrade” the 20 year old lead-acids that needed replacement.

I then picked up a tiny 20w panel that included a 10a pwm controller to trickle charge the battery, again… haha this was all before I started really vesting time into figuring out what I was doing… I’ve since purchased 2x180w bougerv rigid panels for the roof, a Victron 100/20 w/bluetooth controller, victron battery protect, and victron bmv-712 monitor to eventually add to the system.

The system works fine for what it is, and until I can expand my wife’s mindset on camping, (haha good luck to me right?!? :joy:) we’ve been mostly camping connected to shore anyways. So I haven’t had the real need to connect my added panels/solar generators to this system yet, and a huge plus, I didn’t need to spend extra money in replacing the progressive dynamics pd9130 converter and janky electrical wiring/system that was already in place.

When I switch to lifepo4 down the line, that pd9130 will need to get upgraded as it isn’t meant for lifepo4 battery chemistries, but anyways, my question for you sir… is how are you doing your “transfer switch” to get the different systems to work properly?

For simplicity sake, let’s just say all powered appliances are 12v, running from my 12v fuse panel. (Ignoring the inverter I currently use for high draw AC items)

I’ve picked up a blue sea 6007 4-position battery switch but my issues come with how to get it setup properly so that I can switch between using my house batteries and solar generator, all while being able to charge either system via the solar lines, shore power/converter lines or tow vehicle aux/converter lines?

Here’s the blue sea 4-position switch I purchased…

Is this one even going to work??

I know the so-gen(solar generator) has an internal mppt so I will need to have a another, separate switch coming from the panels to bypass the charge controller when solar charging my so-gen. But how do I go about wiring the blue sea transfer switch to select what source is powering the 12v fuse box/appliances, while keeping the existing converters functions?

Could you possibly upload a picture of your wiring setup when you get it dialed in by chance John?? I’m eager to learn and appreciate any and all tips from the pros such as yourself! Haha

Well, sounds like we have the same thoughts and went down the same paths. It can be addicting playing with solar. First off, I love the Vmax batteries and especially the way they conduct their business and treat their customers. First rate!

The items you have purchased so far are awesome. Great choices. For my build and being able to charge the AGM or the EB70, I had originally planned on using a similar Blue Sea Battery Switch selector but without the 1&2 combined. So mine is just 1 or 2 or (off). My original thought was to have the positive from the solar panel feed the Switch (input) and then 1 face the AGM battery and 2 face the EB70, since the AGM has its own MPPT and the EB70 has its own MPPT. This way I would never be feeding both the EB70 and the AGM at the same time. Problem is I couldn’t get a definitive answer about the negative wires. I planned on the negative wires all being tied down to a negative bus bar but I got mixed responses from folks that know more then me as to whether or not this might cause problems. In the end, I decided to just have a couple SAE connectors in my wiring enclosure, one facing the EB70 and one facing the AGM. Very simple and very manual. haha.

So when I want to feed the AGM with solar, I just take the SAE from the solar panel and plug into the SAE facing the AGM battery. The same for the EB70 when I need solar to charge it. Sorry not very spectacular.

For your setup:
I would suggest wiring it like we did our Aliner camping trailer. The batteries were hardwired to the converter and the MPPT at the same time. (we did also have a battery disconnect switch so we could eliminate parasitic drain when not using the camper) When you have sun and your Blue Sea switch is on facing the batteries, it will feed power your AGM’s. I am not sure what would happen if the Blue Sea was set to both 1&2. I think you will just have it set to 1 or 2 or off. I would then have a 2nd Blue Sea Switch for the negative wires from the solar panel and then from both the MPPT and your Bluetti. I thought about doing this with my setup but I am pretty limited on space in the van.


Blue Sea Positive Input is from Solar Panels
Output 1 faces positive towards battery
Output 2 faces positive towards Bluetti

Blue Sea Negative Input is from Solar Panels
Output 1 faces negative towards battery
Output 2 faces negative towards Bluetti

When you want to charge up the Bluetti, you just set both Blue Sea Switches to #2 on both switches. Sorry but that is the best I can come up with.

Oh just re-read your comments. Let me draw it out and think about it a bit before I reply. I have a google docs spreadsheet on my build and will forward it a bit later once I can share it.

Sorry I am not more help!

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Hey Mike,

If I understand, you have your two AGM batteries and you have a Bluetti also. (BTW…which Bluetti model do you have?) You want to say run off your AGM batteries in the Scamp and when it starts getting low, switch to the Bluetti? Sounds like what we were originally trying to do.

I don’t know for sure, but it sounds like you would be best suited to have two Blue Sea Switches. The one with 1 or 2 or off. You would tie your positive from your AGM batteries down to say #1 and tie your positive from the Bluetti down to #2 on one switch. You would need to do the same with the negative cables from each to a 2nd Blue Sea Switch. You would then just have both switches on #1 when using the AGM house batteries or switch them both to #2 for running off your Bluetti. I guess I am assuming due to the Bluetti Forum that your solar generator is a Bluetti. ​To clean up the wiring and make it look nice, you might want to add bus bars if you have the space.

Typically in trailers, the house batteries are grounded to the frame of the trailer where as in our van, as long as I am not tying into my starter battery and charging system, I don’t need to ground my AGM house batteries to the frame or my Bluetti. So I am told by those I trust. Your AGM batteries probably already have a larger awg cable from the batteries to the trailer frame. It is possible that since your solar generator would also be providing power to your Scamp converter, you may need to ground your solar generator to the same frame ground.

For our setup, I decided since it is just a camping van and we are not full time vanners, I will just worry about using the Bluetti for our 12V DC fridge and maybe charging our phones. Our AGM battery can then just worry about keeping our MaxxFan running, LED lights and sink water pump. This is our plan anyway and I typically change things every few months. Ugh

Charging your two setups with your two solar panels becomes a bit trickier. I might consider just having one panel connect to the AGM batteries via the Victron MPPT and use the other solar panel to charge your solar generator.

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No that is all very helpful @SierraVanCampers !!

I figured a 2nd switch will be necessary as the house batteries(AGM’s) will need that charge controller but you explaining with the +/- orientation helps a lot. Thank you! I currently haven’t put in any busbars, but that’ll def help clean/simplify things up.

And now that I think about it… I don’t even think I have anything “grounded” currently! By putting in that negative busbar, I’ll get that taken care of immediately.

Like you, my plan is to use the house batteries mainly for my DC appliances, and my Bluetti AC200 for the larger (AC) loads. Doesn’t make much sense to run the AC200 on smaller loads due to the massive inverter and power consumption.

I did however add a cable to my 12v fuse panel that can now plug into the 12v/25a aviation plug of the ac200 if I ever wanted to run it off the solar generator but have found the 2x85ah (85ah usable) vmax batteries to have plenty of juice for the DC items, so I’ve just been keeping things separate for now.

Yea and please shoot me over that wiring diagram or share the link when you get a chance too!! I’d love to see how you have things done up. Visual aids are always a blessing! Haha

Thanks again for your time. Cheers!

Sounds like a killer setup. I should have my Bluetti later in the week and will post up how I end up wiring and setting it up. Just an FYI, I use a company called Powerwerx for cables and connectors. Not necessarily the cheapest but great service and usually everything is always in stock. I normally make all my own connectors and cables but tried them for a couple of pre-made Anderson connectors and they are first class. Only thing I don’t recommend them for is their “to small” battery disconnect switch. Otherwise great company.

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Excellent info @SierraVanCampers ill look into them!