Evening all..I am in the process renovating my 32' TT to use for fulltime living..My wish is to dry camp 75 percent and shore power 25 percent (may change) I do have a 2500 protable gen need be..So i wish to start with a 400 watt solar system 12 volts that can be expanded to maybe 2 portable panels and more batteries if need be..I'm a brick and motar guy so i would rather do Willie Nelsons taxes with a abacus than electrical work But, if i'm going to live in TT i want to know the in's and out's..I have only purchased a Giandel 2200 inverter..The other main componets i am leaning to are: Renogy 400 watt 12volt Premium kit w/ 40a CC. 2-Chins 12v 100ah Lithium batteries w/1 blue sea 250a Terminal fuse. AiLi volt meter. others are on diagram.. I want to put all components on diagram in closet at very back of trailer. Solar panels would fit directly above and my existing 30 amp power feed is there also that i wish to hard wire to inverter via transfer switch.. My DC panel is 30' to front of trailer.I am still not 100percent sure of wire,lugs,fuses types and brands. i am leaning on crimping my own "just because". I do not have a DC frig..I plan to run a wire to tongue of trailer for break-away system..Any and All input,advice,examples would be greatly appreciated Thank You Ed
All Chinese to me
- Thread starter Tuna1
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Have you done any living in a camper before? The reason I ask is that normally the first thing you would do is a power audit to see how much energy you will actually use. You need to know the minimum you will need to get by. This is a difficult thing to guess if you have no real life experience. Your needs will be different from ours as well as some of your limitations. We are a family of 6 and off grid camp as much of the year as we can in our 38’ travel trailer that we rebuilt during COVID.
Here’s how we ended up with our system
Inverter size 3500w = 30amps max that we can use with the existing electrical system
Inverter type AIO (all in one) it fit exactly in the space we had available and was the most expensive unit we could afford at the time. Still it was only slightly more expensive than lower power options in a similar quality range.
Batteries - originally I bought 4 fla batteries to get the system up and running. Once each the camper was ready for the road I upgraded to lifepo4 needing the additional performance expanded mounting options and lower weight.
Solar panels. As many as we could fit using readily available commercial grade used panels so in it’s final form we have Twelve 270 watt lg mono crystalline panels.
Voltage - we went with 48v as the options are plentiful and instead of operating at the highest amperage that a 12v system can comfortably provide we operate at about the lowest end of amperage that a 48 volt system has components readily available for. This means we use the least amount of space for the amount of power that we have available.
In the process of your planning for the system that’s right for you I would suggest that you figure out what your dream system would be and then calculate the cost for that make sure that your dream system is actually substantially more expensive before going small. Consider planning ahead to create your dream system without having to throw away components you’ve already purchased. consider rebuilding the trailer and putting in place the wiring that you need for your solar system but not actually designing one until you have had a chance to actually try out your power consumption in the unit that you’re creating. Consider using high-quality used commercial solar panels. They are pennies on the dollar and very effective. If it all possible go with Lifepo4 batteries. There is just no better chemistry available today for a travel trailer application. You will take full advantage of every benefit that lifepo4 can provide in a mobile application.
B-ManFX4
Solar Enthusiast
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As was stated you really need to determine how much energy you will normally use. Sizing the system to accommodate your needs on the front side will greatly reduce the amount of hardware buying and replacing that will happen if you start out under sized and then have to upgrade.
I know you have already purchased the inverter but if you can return it or sell it I would strongly consider going with a 24VDC or higher AIO system. Using an AIO will eliminate hardware, improve simplicity, reduce wiring size and reduce your component count. You can drastically reduce your wiring sizes and take advantage of greater MPPT capacity by going with a higher voltage system too. For example the MPPT I am using is rated as follows:
650 watts @ 12VDC
1,300 watts @ 24VDC
1,950 watts @ 36VDC
2,600 watts @ 48VDC
I say this because I am guessing you will find that you will need way more solar power than you are planning for right now. If I were you I would look for used commercial panels and avoid that Renogy kit. I bought three 380 watt commercial mono panels for $250 each. One of my panels outputs roughly the same wattage as that entire Renogy kit - with only four roof mounting bracket penetrations. Paired with a Victron 150/45 MPPT ($385) the cost would be close to the kit and it offers much greater expandability. The Victron MPPT has built-in Bluetooth and will work with 12, 24, 36 and 48 volt systems. It is also "smart" so it can properly charge FLA, AGM, Li-Ion, LiFePO4, etc.
I personally use Victron equipment and the software support and system integration is fantastic. I can switch between 30 amp parallel and 50 amp split-phase operation using just my phone and their app - and do it in less than a minute. The system analysis and status display capabilities of their software just plain works well. Don't underestimate the value of being able to see what is happening with your system without having to open a closet and put a multi-meter on various test points.
The advice on the LiFePO4 batteries is spot on. I would add that if you really think you may add additional batteries, go ahead and buy 200AH batteries now instead of the 100AH units. You will have fewer connections, a reduced footprint and twice the capacity. If you decide to go 24VDC you can buy a 24VDC battery and further reduce your footprint and connection counts. If your batteries will live in the air conditioned space you can avoid the extra expense of the self-heating option.
I took a stab at a system diagram. I hope you find it useful.
I know you have already purchased the inverter but if you can return it or sell it I would strongly consider going with a 24VDC or higher AIO system. Using an AIO will eliminate hardware, improve simplicity, reduce wiring size and reduce your component count. You can drastically reduce your wiring sizes and take advantage of greater MPPT capacity by going with a higher voltage system too. For example the MPPT I am using is rated as follows:
650 watts @ 12VDC
1,300 watts @ 24VDC
1,950 watts @ 36VDC
2,600 watts @ 48VDC
I say this because I am guessing you will find that you will need way more solar power than you are planning for right now. If I were you I would look for used commercial panels and avoid that Renogy kit. I bought three 380 watt commercial mono panels for $250 each. One of my panels outputs roughly the same wattage as that entire Renogy kit - with only four roof mounting bracket penetrations. Paired with a Victron 150/45 MPPT ($385) the cost would be close to the kit and it offers much greater expandability. The Victron MPPT has built-in Bluetooth and will work with 12, 24, 36 and 48 volt systems. It is also "smart" so it can properly charge FLA, AGM, Li-Ion, LiFePO4, etc.
I personally use Victron equipment and the software support and system integration is fantastic. I can switch between 30 amp parallel and 50 amp split-phase operation using just my phone and their app - and do it in less than a minute. The system analysis and status display capabilities of their software just plain works well. Don't underestimate the value of being able to see what is happening with your system without having to open a closet and put a multi-meter on various test points.
The advice on the LiFePO4 batteries is spot on. I would add that if you really think you may add additional batteries, go ahead and buy 200AH batteries now instead of the 100AH units. You will have fewer connections, a reduced footprint and twice the capacity. If you decide to go 24VDC you can buy a 24VDC battery and further reduce your footprint and connection counts. If your batteries will live in the air conditioned space you can avoid the extra expense of the self-heating option.
I took a stab at a system diagram. I hope you find it useful.
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Wow,, Thank you both, this has changed my whole thought process.. The simplicity of your diagram is a big plus. Rethinking and doing it to fit our needs the first time is, well ? common sense lost, in my haste to hit the road..Long hot, muggy summer here.. My thought process on 24volts is/was twice the voltage, twice as complicated so i never looked twice at it. Appreciate your time and input..
B-ManFX4
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I cleaned up the 1st drawing so it is a little easier to follow. I also added the L1 & L2 input labeling for the MP. Since you mentioned a generator I thought it is worth mentioning since the Victron supports it without modification.
I also edited it to reflect how easy it would be for you to expand the charging and run-time capabilities by just adding a battery and solar panel(s). No need to replace any of the existing components.
I also edited it to reflect how easy it would be for you to expand the charging and run-time capabilities by just adding a battery and solar panel(s). No need to replace any of the existing components.
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Vigo
Solar Addict
I didn't notice any issues with your initial diagram, but I agree that you will probably end up wanting more than 400w of solar and might as well plan for it now.
In my opinion the main way to plan for more solar is to pick a solar controller (whether standalone or built into an all-in-one inverter) with the highest max voltage rating, because it will simplify the additional wiring when panels are added. For example, if you did get a controller with 400v+ input limit, it would be difficult to integrate enough panels onto the top of a travel trailer to necessitate any parallel wiring. If you can keep all the panels in series it will simplify both the initial install of wiring, and the changes necessary to add panels down the road (assuming the new panels somewhat match the existing ones). I think the main thing you would want to avoid is the need to create new roof penetrations or upsize the existing cabling going through your penetrations, because that is irritating and just one more possibility for leakage.
And if you are planning for full-time living, you have to consider air conditioning and heating. Air conditioning on solar is 'feasible' in mild conditions on a solar powered RV/TT setup, but not really in hot conditions, and electric heating is likewise not particularly feasible. So for example your 2200w inverter would comfortably run 2 small 5-6000btu/hr units as long as they didn't start up simultaneously. It would probably run one larger ~8k unit. It probably would not be able to start a typical 12-14k rooftop unit. So you either decide that AC use will be limited to generator power, or you plan both the supply side (solar/inverter/batts) and the load side (the ac units) to play nice together from the get go.
I have a somewhat similar situation to you in that i have ~360ah (rated..) of 12v lifepo4 in my RV. I have a ~12-14k rooftop unit which i hate because it's a power hog, and stuck a typical 5kbtu window unit through a back wall. I CAN run that rooftop unit off my 5kw inverter if i chose to, but i choose not to because the continuous 150a+ draw on the 12v side makes me paranoid, even though the system can handle it for a certain amount of time. It just makes me uncomfortable knowing it's happening. I do plan to work on upgrading my wiring until it is feasible to run it continuously when driving off my 200a rated alternator, but im not there yet with my wire sizing/connections. You couldn't run a unit that large off a 2200w inverter at all. However, I can run my 5k window unit quite comfortably for many hours. Overnight off the batteries if needed. During the day i would need to have around 500w of solar to 'break even' and power the unit without drawing down the batteries. The cool thing about AC off solar/inverter/batteries is you don't HAVE to 100% break even from solar. But if that unit would run 8hours or something with no solar, it would run ~16 if i had 200w of solar coming in, etc. Forget that 16 hours of sunlight isn't a thing, just making an example. So if you ever plan to run AC off this setup you should decide that NOW, to minimize the amount of incremental changes you have to make down the road. If you choose not to then it's possible that a 2200w inverter would be all you ever need for most uses, but you will still probably want to end up with more than 400w of solar coming in.
In my opinion the main way to plan for more solar is to pick a solar controller (whether standalone or built into an all-in-one inverter) with the highest max voltage rating, because it will simplify the additional wiring when panels are added. For example, if you did get a controller with 400v+ input limit, it would be difficult to integrate enough panels onto the top of a travel trailer to necessitate any parallel wiring. If you can keep all the panels in series it will simplify both the initial install of wiring, and the changes necessary to add panels down the road (assuming the new panels somewhat match the existing ones). I think the main thing you would want to avoid is the need to create new roof penetrations or upsize the existing cabling going through your penetrations, because that is irritating and just one more possibility for leakage.
And if you are planning for full-time living, you have to consider air conditioning and heating. Air conditioning on solar is 'feasible' in mild conditions on a solar powered RV/TT setup, but not really in hot conditions, and electric heating is likewise not particularly feasible. So for example your 2200w inverter would comfortably run 2 small 5-6000btu/hr units as long as they didn't start up simultaneously. It would probably run one larger ~8k unit. It probably would not be able to start a typical 12-14k rooftop unit. So you either decide that AC use will be limited to generator power, or you plan both the supply side (solar/inverter/batts) and the load side (the ac units) to play nice together from the get go.
I have a somewhat similar situation to you in that i have ~360ah (rated..) of 12v lifepo4 in my RV. I have a ~12-14k rooftop unit which i hate because it's a power hog, and stuck a typical 5kbtu window unit through a back wall. I CAN run that rooftop unit off my 5kw inverter if i chose to, but i choose not to because the continuous 150a+ draw on the 12v side makes me paranoid, even though the system can handle it for a certain amount of time. It just makes me uncomfortable knowing it's happening. I do plan to work on upgrading my wiring until it is feasible to run it continuously when driving off my 200a rated alternator, but im not there yet with my wire sizing/connections. You couldn't run a unit that large off a 2200w inverter at all. However, I can run my 5k window unit quite comfortably for many hours. Overnight off the batteries if needed. During the day i would need to have around 500w of solar to 'break even' and power the unit without drawing down the batteries. The cool thing about AC off solar/inverter/batteries is you don't HAVE to 100% break even from solar. But if that unit would run 8hours or something with no solar, it would run ~16 if i had 200w of solar coming in, etc. Forget that 16 hours of sunlight isn't a thing, just making an example. So if you ever plan to run AC off this setup you should decide that NOW, to minimize the amount of incremental changes you have to make down the road. If you choose not to then it's possible that a 2200w inverter would be all you ever need for most uses, but you will still probably want to end up with more than 400w of solar coming in.
More options.. Thank you... I am doing a energy use audit now (as I have read 1,000 times ) and I really don't see a need to run A/C off my solar system. If need be i would use generator or go to full hook-up.. And concerning the diagrams I don't understand the L2 generator socket? I have a portable inverter gen wouldn't I just plug it into my shore power socket (L1) or does the Multiplus have wire leads/studs inside dedicated for generator?
Vigo
Solar Addict
Depending on how you wanted to do it you could hardwire the generator to the inverter input and leave your shore power cord for only shore power. Whether that's an advantage i guess depends on what type of generator and whether you would like to just mount and hardwire it somewhere and never move it. If it were already a hard-mounted generator the choice would be more obvious.
B-ManFX4
Solar Enthusiast
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The L2 output is not connected to the inverter output. The inverter output only feeds L1. In other words, anything you might want to run when on generator but not when on battery (AC, big heater, etc.) you could wire to the L2 output. Plenty of folks have a generator wired into L2 so that if shore power drops the generator auto starts and keeps the stuff connected to L2 running.
Lots of options with Victron gear.
Lots of options with Victron gear.
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