Hi. I’m researching the best inverter/charger and battery set up for my trailer conversion. I’m looking to move away from rv campgrounds with hookups to off grid camping.
I have a 7x16 Weeroll camper. It came wired with 30A service. It has the 30A shore power plug, a breaker box with a few circuits for AC and DC.
I have a 12 volt 10,000 btu roof mount AC, a mini fridge, tv, and recharge phones mainly. I have a champion portable 4500 watt inverter generator that runs the camper fine. However I want to limit the generator use.
So I’m looking to set up a system in 2 phases. In phase 1, I will run the generator 2-3 hours a day to recharge the batteries and then have the batteries keep the fridge on, starlink running, and a couple hours of tv at night(teenage sons). Will add solar in phase 2.
Looks like the multi plus 2 is the same price as some of the older units but not necessary for my needs(?)so what would you guys recommend for the inverter charger and what battery bank set up?
I’m going twitch the LiFePO4 batteries but not sure the difference between getting say 4 100amp batteries wired in parallel vs 2 200 amp batteries. Is there an advantage over multiple smaller batteries or a couple larger capacity ones?
Thanks for any help you can provide on the best inverter/charger and battery capacity for my set up. Thanks!
if you mini fridge is 12v, then the power consumers are your TV and phone chargers etc. Typically 500W should be fine for those, but do check the TV power rating label, and then add on a couple of phone chargers too.
Only difference is in the flexibility of the volume required. (and the number of wires). Also, if going for a larger inverter than 1500W think about going 24V - you will need a dc/dc converter to do the charging, but that’s normally a good thing to regulate voltage and current better. If your fridge is dual voltage, then no issue, otherwise an additional dc/dc converter required.
Advantages of 24V: lower cost and more efficient inverter, smaller dc cables.
Disadvantage: additional dc/dc converter(s) required.
Mike, thanks for suggesting the 24v system. I’ve been reading more about it and seems like a good option. Especially since I’m designing it from scratch. I don’t have any 12v appliances or systems already in place.
Wondering if a base 24v system inverting mostly everything to 120 would be the way to go since I already have 30amp shore plug and AC outlets. Especially when factoring in up front and replacement cost of 120 vs 12v appliances. My small aluminum trailer is more of an overlanding set up than a traditional rv.
You have several choices here, depending on total power and load complexity.
Certainly 120V appliances will be cheaper than 12 or 12/24 volt appliances, as they are higher volume production.So: you can get a 120V inverter or a 120-0-120 inverter, so it depends on the circuit. You also need to think about an isolation transformer if you are going to be using the shore power input much.
I know @MikeD and others gave you some great guidance. But, if I were to build a rig your size from scratch and had the option to choose my appliances I would run as much as possible(in your case possibly all) on 120V AC off the inverter with a 24V system getting away from as much converting as possible. Fridge, cook top, even water heater(if you have the budget for the battery bank) are very accessible and affordable in 120V versions. I have seen large systems built like this in RVs where the only 12V they have is a small(100AH) battery with a charger or small converter off the multiplus to run the slide outs and and a few other small 12V loads. You could do this with no propane and no converters quite effectively.
How much power do you need? Have you made yourself a power budget? What type of mini fridge do you have (AC, AC/DC, propane)? What is the voltage of the other electrical items in your trailer: lighting, water pump, furnace ??? Do you have propane on board?
I have a somewhat different opinion than what you have gotten so far; Considering your compact overlanding trailer, I‘m guessing that you also have space and weight constraints. So why not keep the electrical system compact as well? The simplest path (this will get me in trouble with the Victron die-hards for sure ) is one of those all-in-one “solar generators” like the an EcoFlow Delta 3 Max Plus. Modern ones have more than enough power for the kinds of things you’re talking about (with the exception of the air conditioner) and everything you need is in one box.
If you have your heart set on a Victron system (I wouldn’t blame you, my whole expedition camper is Victron powered and their stuff is truly fantastic), then I suggest that you go with a 12 Volt system so that you can easily power all of the usual “RV” stuff (lighting, water pump, phone chargers) without the need for a DC-DC converter. A Starlink Mini runs great from a 12V source too . In a trailer your size you might be just fine with a single 200A/h (2600W/h) LiFePO4 battery… If you have doubts then make a power budget to prove this out. Remember that with lithium, unlike lead acid, all of the battery capacity usable. Then you can add an appropriate pure sine wave inverter, like the Victron’s 12/1200 (you don’t need a MultiPlus), and a Blue Smart battery charger. When your ready it’s easy to add on a solar charge controller like the Victron MPPT 100/30, and a couple solar panels (up to ~500W).
If your mini fridge is only mains powered then maybe consider getting a 2nd dedicated small inverter to power it (e.g. VE.Direct 12-375), most mini fridges only draw ~100W or so when running. On the other hand there are plenty of great 12V compressor refrigerators available…. do some googling.
Oh, and I assume that you will want to charge from the tow vehicle while driving; for this you’ll need a DC-DC charger, like the Victron Orion TR 12/12-18.
This is just my 2¢, so take it for what it’s worth… but it’s coming from a guy with a large expedition truck with a big electrical system and a Jeep Gladiator overlanding rig with a compact all-in-one system.
-Mark
Thanks for the great feedback, Mark! My original plan was to go with one of those solar generators. I have a Jackery Explorer 500 with a portable solar panel that we use in the rooftop tent. It works great for minimal needs.
I was planning to get a large one like you referenced and then watched a YouTube video from a guy who was pointing out the difference between that unit and Temgot LiFePO4 batteries and it led me down the rabbit hole of a full build.
I have a plan to add solar up to 600w and thought the full system would be the way to go. The trailer came wired with a 30amp service shore power connection and the breaker box has 120 and 12v circuits. That’s why I thought I should go full build.
I appreciate the specific recommendations! Here’s a pic of my trailer. It’s 100% aluminum 7x16. It’s a blank slate with 30A electricity - just want to get it right! Thanks again, Mark!
Now that I have an even better idea of the size, I am going to double down on my all-in-one suggestion . That said, there is no “right answer”, so choose whatever type of electrical system you think suits your specific needs the best. The Victron stuff I listed in my previous post is a good starting point. Good luck with your build!
I went back and looked at those again and I think you’re spot on with the portable power station. And that specific model I think is the best choice.
I’m researching now what I would need to make that EcoFlow integrate with my existing breaker box that has both 120 and 12 volt circuits. Thanks for the insight, @MarkSiminoff !
That would be a shame in my opinion. You have the opportunity to build a reliable, customized, fully configurable, infinitely repairable, upgradeable,(and other “ables” I am sure) system with great support. Don’t put in a chunk of Amazon product of questionable quality that you will never be able to do any of this with. You can’t upgrade the battery, can’t configure or troubleshoot individual components, are forever limited to its existing features. Can you even replace individual components if they go bad? What kind of support is there? The concept may seem attractive of an all in one unit but please reconsider.
@TherealKT I hear you and I would prefer the full build. That’s what originally brought me here. I spent hours researching and have a basic grasp of the parts needed But I’m not confident in my ability to build the system.
My trailer is pretty small and the advantage of the all in one system is that I could use it for my business too when I’m not camping.
However, I know I’d be running my generator more often with the ecoflow bc I’m not buying multiple extra batteries from them.
I got a quote from Explorist Life but they’re on the west coast and I’m in north Florida so that doesn’t seem doable.
I’ll continue to research before pulling the trigger thanks for your feedback KT!
I have small camper trailer that I initially built with 12V system and 1000W inverter with 100Ah battery. Last year I decided to do an upgrade and went for 24V system. I was able to integrate DIY battery with 8 LiFePO4 cells into the the camper body. So I have 305Ah@24V battery. On the rooftop I have single bifacial tiltable 550W solar panel (upgraded from 2x100W panels). Fortunately I used all Victron stuff from the beginning so I didn’t need to change MPPT, since it was 12/24V model (100/30). The only non-Victron thing is 3000W inverter. I would have liked to use Victron’s 24/3 kVa Multiplus, but unfortunately it was too big to fit into the camper’s preferred location. Couple of months ago I also upgraded the hot water system. Initially I used instant propane heater, but it was not very convenient due to the fact the door had to be open (exhaust gases) all the time I needed hot water. Now I installed small electric hot water boiler manufactured by Tigerexped. It is natively 24V model, so it runs straight from the 24V bus bar. The fridge is also 12V/24V compatible, so I didn’t need to do any upgrades due to voltage change. Also, I use 24V diesel heater (Autoterm). Since some of the installed LED-s and water pump is 12V I had to install additional 24–>12V Orion High power converter for these appliances. Inverter is now used for induction cooktop and electric water kettle.
Just recently (for pitch black winter season) I also installed Orion XS 1400, so that I can charge 24V trailer battery with the car’s 12V alternator. Since my car’s starter battery is placed in the boot it was quite an easy install with Anderson connectors. Orion 1400 lets you dial input-output voltages as well as current if you are afraid of overloading the alternator.
All-in-all I suggest 24V system if you intend to use more than 1500W inverter. You need to consider the right voltages also when choosing the solar panels.
It’s good to hear another vote tor 24v. I decided to post here to get feedback before pulling the trigger. I’m in the design phase and really appreciate all the input.
) is one of those all-in-one “solar generators” like the an 
. In a trailer your size you might be just fine with a single 200A/h (2600W/h) LiFePO4 battery… If you have doubts then make a power budget to prove this out. Remember that with lithium, unlike lead acid, all of the battery capacity usable. Then you can add an appropriate pure sine wave inverter, like the 