Solar Build for Travel Trailer - Requesting Help

[TravelingSLO]

Hello, Kim here! Brevity isn't my strong point - so I apologize in advance for what will probably read like an overly long novel. Also, the thing I care most about is safety. Fire scares the shit out of me, and I don't want to burn my wee house down. Also, someone suggested revising this post, so here we go:


I am confused about the following:

• Is this the worst idea I've ever had? We take long trips - like months at a time - and the current battery setup sucks. And requires us to regularly find shore power, or run an extension cord from the inverter in our truck through the window to our dinette so Eric can charge his laptop for work. Honestly, we could live without most of the RV stuff for days on end, but the Wi-Fi, laptop, and phone charging is required for work.
• Series or Parallel - I will be facing shady situations, so I am thinking parallel might make more sense. I've tried to understand series vs. parallel, but I am not winning at this - can someone just tell me which one to pick? I only have two panels, they match, and there will probably be shade in my future.
• Do I remove the existing "electricity brain" in the RV? It has a WFCO 8900 series Power Center currently installed. Is the idea with this new build and selection of products that I basically gut all the stuff in there and replace it with the new equipment? I haven't seen this mentioned clearly in any of the dozens of videos I've watched, but it seems like I am replacing the existing unit with better individual components which will allow the lithium battery to be charged and all of the AC/DC devices to be used.
• Do I need a shutoff or transfer switch or something to disconnect the various parts? If so, can you tell me which item and where it goes?
• Wire. Oh my, wire. I have read the Victron Wire Guide and am still somewhat confused. I know I need thick large gauge wire for the battery situation, and a smaller gauge for everything else, but I am wondering should I go with larger wire than required for safety? What's the best choice here? Also, I need black wire and red wire, and what about a grounding wire? I assume there is a ground attached to the current WFCO Power Center, can I use that one?
• The fuse/breaker situation - there's fuses everywhere, and a breaker, and also, maybe I don't have the right types/sizes/etc. I ordered two fuses which I think might be to small, and then I also ordered a circuit breaker which might be too large. I tried to read up on here, and it seems like folks often recommend the Class T fuse; I am happy to order one, but which one exactly? And where exactly does it go?
• Some folks on here really hate on the Renlogy stuff - and I have a Renogy 40A 12V/24V Auto DC Input MPPT Solar Charge Controller w/ Bluetooth. If this is the biggest mistake I am making, tell me now so I can return it.

Background, if you care!
I have a Riverside Retro 189R travel trailer; purchased new in 2020; it currently runs 12V DC from a DieHard Silver Marine/RV Deep Cycle battery and 110V AC on a 30amp setup when connected to shore power - it has a port for Zamp Solar panels, but I assume it's basically a BS thing, as it's halfway down the side of the rig, and the last thing that said it was "pre-wired for a backup camera" meant "we drilled a hole in the aluminum for you, get some tweezers and grab the wires and figure out how to wire it yourself lady." We'd like to be doing a LOT more boondocking than we have been doing, but we need to have a more stable battery setup to do this. Also, when it's parked and we are in a house, I'd like the solar panels to keep the battery charged.

I am installing a solar setup + LiFePO4 206Ah battery following Will's basic DIY 400 Watt 12 volt Solar Power System - I have watched the videos, read the book, but I still have questions. I have also referenced a number of other YouTube videos and the Asobo Camper Van Solar Build website and free e-books on the topic. I discussed options with Dexter at Current Connected, whom I obtained some of my system components from (I recommend them - he's super helpful and friendly!) I've done an energy audit to the best of my ability, and we are also happy to conserve to meet the needs of this system - the most important thing that runs is a Wi-Fi router which we had converted to DC (on the second try - first tech caught the wires on fire and melted it before giving up).

While I completely new at this, I can follow written instructions, and my best friend has a CS/EE degree and is very handy with electrical wiring, so I believe I can actually accomplish this mostly on my own with his help (I've had crappy luck trying to hire someone to do RV repairs unfortunately, so I think I will actually care more than the three techs we've used thus far - and therefore do a possibly better job at this solar thing.)

I've tried to refer to threads on here, such as this one, but I'm not always clear on if they apply to my situation, hence this long post.

The components I've bought are:

• 2 - 200W Rich Solar Monocrystalline Panels
• Victron | SmartShunt | 1000A | 6.5-70vDC
• Renogy 40A 12V/24V Auto DC Input MPPT Solar Charge Controller w/ Bluetooth
• MegaFuse Holder + 2 Fuses for Inverter
• 2 - (Red & Black) 4 Stud Bus Bar Power Distribution Block with Cover
• Large fuse for the MPPT/Renogy 40A Set w Holder ANL Fuse
• T Tocas 50 Amp Thermal Circuit Breaker with Switch Manual Reset for Boat Marine RV Yacht Battery Truck Solar, 12V - 48V DC, Waterproof (50A)
• 1 - SOK Battery | 206Ah 12v | LiFePO4 Battery | Solar Battery - Welded / Powder-Coated Metal
• Giandel Pure Sine Wave Power Inverter 2200Watt
• Cable Entry Gland (I bought two accidentally - so there is the BougeRV and the Link Solar)
• Blue Sea Systems 5026 Blue Sea Systems ST Blade Fuse Block 12 Circuit with Ground and Cover
• Renogy 15A Male and Female Connector Waterproof in-Line Fuse Holder w/Fuse, Black
• Crimp Connectors/ELECFUN 56pcs Battery Cable Ends 8-4 AWG Heavy Duty Wire Lugs Tinned Copper Eyelets Battery Cable Ends
• Crimp Connectors/Wirefy Heat Shrink Wire Connectors Kit - Marine Grade Electrical Connectors
• Litorange 325Pcs Rubber Grommet Eyelet Ring Gasket Assortment - 1/4", 5/16", 3/8", 7/16", 1/2", 5/8", 7/8", 1" for Automotive, Wire, Plug and Cable (to protect the cables going into the aluminum - recommended by the couple at Asobo, and made sense based on my install of the backup camera)
• BNTECHGO 10 Gauge Flexible 2 Conductor Parallel Silicone Wire Spool Red Black High Resistant 200 deg C 600V for Single Color LED Strip Extension Cable Cord,Model,50ft Stranded Copper Wire (does this wire suck? Someone on either here or another site recommended this specific wire, and I can't seem to find any locally, although I have a new lead)

Still need to buy:

• Z-brackets for mounting solar panels
• Solar panel extension wires w/ MC-4 and inline fuses
• Branch Connectors
• Wire Crimping Device (looking at this one from Harbor Freight)
• Wire
• Lap Sealant
• Probably a thousand other things you will hopefully inform me of?

I am sure I have six zillion additional questions, but if I keep thinking of them, I will never post this and never start my install. Thanks you for reading and thanks for any help you're willing to provide. I'll happily bake anyone cookies in my adorable wee oven - once I get this thing working again - and deliver them if you'll help me.

 

[400bird]

Honestly, I didn't get very far into your post and jumped straight to the pictures.

Your charge controller has a "Max. PV Input Power 12V/260W"
Your two panels are over that threshold. I'd either get a second charge controller, or (preferably) one charger controller that hand handle the two panels in series.

You don't need fuses on the panel wiring if you size the wires to carry all the current the panels can put out. A breaker will allow you to open the circuit if you need to service the system.

Also, you should probably connect your solar charge controller to the battery.

That's as far as I got. Seems like you've done a lot of research and have the start of a great plan.

You might get more responses if you bullet the questions at the top of your post or put the image up near the top.

 

[TravelingSLO]

Thanks for your response!

Honestly, I didn't get very far into your post and jumped straight to the pictures.

Brilliant! I am a words person (clearly). Glad the drawing worked out. I also didn’t think of how it would look on mobile.

Your charge controller has a "Max. PV Input Power 12V/260W"
Your two panels are over that threshold. I'd either get a second charge controller, or (preferably) one charger controller that hand handle the two panels in series.

I’ll get a different one.

You don't need fuses on the panel wiring if you size the wires to carry all the current the panels can put out. A breaker will allow you to open the circuit if you need to service the system.

Excellent.

Also, you should probably connect your solar charge controller to the battery.

Yes, I might’ve gotten a touch distracted when the “drawing the lines” part of making the illustration happened.

That's as far as I got. Seems like you've done a lot of research and have the start of a great plan.

Clearly NOT enough research, but this has helped point me in the right direction.

You might get more responses if you bullet the questions at the top of your post or put the image up near the top.

Okay! I’ll edit the post.

 

[400bird]

Thanks for your response!
Glad to help.

Brilliant! I am a words person (clearly). Glad the drawing worked out. I also didn’t think of how it would look on mobile.

I'm normally in for a long read, just wasn't in to today.

Yes, I might’ve gotten a touch distracted when the “drawing the lines” part of making the illustration happened.

Haha, it looks so nice, I almost didn't notice.

Clearly NOT enough research, but this has helped point me in the right direction.

A second set of eyes...

 

[TravelingSLO]

I'm normally in for a long read, just wasn't in to today.

I understand.

I am thankful for the second set of eyes as this has been pretty much all me up to this point, and I needed to get it out of my head and onto paper.

I feel super dumb that I selected the wrong charge controller and didn't realize that it would not work - I am going to go through and look at all the elements again.

Haha, it looks so nice, I almost didn't notice.

Well, I think that we might notice if the lights don't turn on (although, honestly, they don't work for very long now, so, maybe we wouldn't.)

 

[B-ManFX4]

I took a stab at editing an existing diagram I had and inserting your components.

 

[TravelingSLO]

I took a stab at editing an existing diagram I had and inserting your components.

View attachment 103491

That’s amazing! It seriously took me like two days to make that other thing. i’m going to frame this and hang it up in my RV. Thank you!!!!

 

[B-ManFX4]

We should discuss your plans and expectations. I think you might like a change or two, depending on your exact scenario.

 

[TravelingSLO]

We should discuss your plans and expectations. I think you might like a change or two, depending on your exact scenario.

I’m happy to make changes and would love feedback. I’ll provide some info, feel free to ask questions if I don’t answer yours.

Basically we’d like to be able to boondock for an unspecified amount of time. I’m guessing around a week would be ideal, but I’m probably more limited by blacktank issues than electricity.

We are likely to be chasing good weather, we’ve got a generator but rarely use it (heavy, not silent). Above all access to power to run our homebrew Wi-Fi router and charge the laptop; keep the fridge fan/electric components running while on propane. Cooking can be propane.

I’d like a system that somewhat minds itself - like the solar will help keep the batteries healthy if we are not on the road. So if I need a battery manager or something, do tell. I’ve got room for one more panel up top. And I could get more batteries. But I figured if this totally sucked at least I wouldn’t be in for 10K.

Honestly, this is my first foray into solar or even understanding electrical. I’ve got basically zero real science in HS or college, but I’m finding it fascinating. So any help or direction is greatly appreciated.

 

[B-ManFX4]

If you are planning on boondocking for longer periods of time I think more battery capacity is going to be a bonus. Adding another solar panel will help too.

One thing I think you should consider is an inverter / charger. That simplifies system design and it allows you to charge your batteries from shore power when you have it. The Victron units I used transfer so fast there isn't a blip when I unplug shore power.

I recently finished my boondocking build. I know it is overkill for your application but it can be scaled back as needed. This setup gives me 4,800 watts of power across both sides of my RV breaker panel. It will run my 15K AC unit over 10 hours without any solar input - much longer if the sun is shining. The NEMA plugs allow me to remove the system from my RV and re-connect the electrical like it was when I bought it. I can use the system and batteries in my house if needed.

 

[B-ManFX4]

I should have noted - I went with a 24VDC system to lower wiring sizes and to take advantage of better solar performance, lower losses, etc.

 

[emerge411]

Some ideas to add:

• You might want to bump your 2200w inverter to 3000w if you really are going to run some larger things like a microwave and A/C. Better to have some more head room especially with a high frequency inverter. Both these inverters would push more then the 100A discharge a single SOK battery is rated for. I would suggest bumping up to two to run a 2200w or 3000w inverter. I have other reasons to add a second battery farther down the list.
• You can keep the WFCO 8900 but make sure the converter can support LiFePO4 charging. You can buy a separate converter/charger and still keep the WFCO for distribution if it doesn't.
• If you want the inverter to supply all the outlets with power when your not on the grid you need some sort of transfer/change over switch to switch the AC input between the shore and inverter power. You also want to make sure your converter doesn't try to charge your batteries while your running on your inverter. I don't see any of the AC wiring in your diagram yet. If your just going to use the outlets on the inverter then its not an issue but that will make running things like your microwave hard since you like don't have access to the plug. A changeover switch (search "change over switch" on amazon) might be a cheap option to switch between sources and could also be used to only connect the converter when connected to shore power.
• You can also try to keep more things on DC. Both your laptop and phones can run off DC vs using the AC adapter just to convert back to DC. I like to add 12v power outlets that you can use car chargers in. As the USB/charging standards change and advance you just swap a charger. There are some USB chargers that can put out plenty of power for a laptop or phone.
• Ignore the prewired for solar zamp stuff it is just a wire running to your batttery box
• If you can afford it another SOK battery will make you very happy especially if you have a 12v compressor fridge. With only 200ah your going to only get maybe a hour of A/C run time when factoring other loads in. If you plan is to run it before bed that doesnt work well because you wont have juice left for the night. You will need another SOK to have any real use of the A/C in my opinion. I have 600ah and I still get "range" anxiety when running my A/C.
• Think about your breakaway system. There is some disagreement about tying your breakaway system to you lithium batteries. I suggest getting a inexpensive dedicated breakaway battery and leaving both systems totally separate.

I recently posted my RV build which has a schematic of all the connections and fuses and what not if it is helpful.

 

[TravelingSLO]

If you are planning on boondocking for longer periods of time I think more battery capacity is going to be a bonus. Adding another solar panel will help too.

One thing I think you should consider is an inverter / charger. That simplifies system design and it allows you to charge your batteries from shore power when you have it. The Victron units I used transfer so fast there isn't a blip when I unplug shore power.

I recently finished my boondocking build. I know it is overkill for your application but it can be scaled back as needed. This setup gives me 4,800 watts of power across both sides of my RV breaker panel. It will run my 15K AC unit over 10 hours without any solar input - much longer if the sun is shining. The NEMA plugs allow me to remove the system from my RV and re-connect the electrical like it was when I bought it. I can use the system and batteries in my house if needed.



View attachment 103527

Wow, 10 hours for an AC is impressive. And using it in a house is a huge plus.

Some ideas to add:

• You might want to bump your 2200w inverter to 3000w if you really are going to run some larger things like a microwave and A/C. Better to have some more head room especially with a high frequency inverter. Both these inverters would push more then the 100A discharge a single SOK battery is rated for. I would suggest bumping up to two to run a 2200w or 3000w inverter. I have other reasons to add a second battery farther down the list.
• You can keep the WFCO 8900 but make sure the converter can support LiFePO4 charging. You can buy a separate converter/charger and still keep the WFCO for distribution if it doesn't.
• If you want the inverter to supply all the outlets with power when your not on the grid you need some sort of transfer/change over switch to switch the AC input between the shore and inverter power. You also want to make sure your converter doesn't try to charge your batteries while your running on your inverter. I don't see any of the AC wiring in your diagram yet. If your just going to use the outlets on the inverter then its not an issue but that will make running things like your microwave hard since you like don't have access to the plug. A changeover switch (search "change over switch" on amazon) might be a cheap option to switch between sources and could also be used to only connect the converter when connected to shore power.
• You can also try to keep more things on DC. Both your laptop and phones can run off DC vs using the AC adapter just to convert back to DC. I like to add 12v power outlets that you can use car chargers in. As the USB/charging standards change and advance you just swap a charger. There are some USB chargers that can put out plenty of power for a laptop or phone.
• Ignore the prewired for solar zamp stuff it is just a wire running to your batttery box
• If you can afford it another SOK battery will make you very happy especially if you have a 12v compressor fridge. With only 200ah your going to only get maybe a hour of A/C run time when factoring other loads in. If you plan is to run it before bed that doesnt work well because you wont have juice left for the night. You will need another SOK to have any real use of the A/C in my opinion. I have 600ah and I still get "range" anxiety when running my A/C.
• Think about your breakaway system. There is some disagreement about tying your breakaway system to you lithium batteries. I suggest getting a inexpensive dedicated breakaway battery and leaving both systems totally separate.

I recently posted my RV build which has a schematic of all the connections and fuses and what not if it is helpful.

I am sorry about my odd reply. I started it on my phone and realized using my laptop would be a better choice. In the middle of going to get the laptop, I knocked over a quart of vegetable oil which spilled under my W/D and have spent the last hour cleaning that mess up. I’ll reply from the laptop soon, and I really appreciate the time everyone’s spent thoughtfully making suggestions!

 

[PlanetExcellent]

I'm in a somewhat similar situation as you, and I'm in the middle of building a similar system (2x 200w panels, 2x 200Ah lithium, inverter). Here are a few choices I made:
1. For me, the hard limiting factor to boondocking endurance isn't electrical, it's water. My trailer has 30 gallons of fresh water and a 30 gallon grey tank. Our initial camping experiences taught us that we use about 5 gallons per day, so 6 days is about the limit no matter how many batteries or panels we have.
2. I was willing to spend more to hook up less stuff. After pricing out a decent inverter, a good battery charger, and an automatic transfer switch, I was within a couple hundred bucks of a really nice name brand inverter/charger/ATS. I bought a Xantrex XC 3000. Much easier to hook up and only one box to mount instead of 3.
3. With the inverter & batteries, I wanted to be able to power the microwave/convection oven, the AC-powered TV (although it's a small one that doesn't use much power), and use all the lights and 12-volt stuff. A 200Ah lithium battery and 2000w inverter was going to be marginal so I might need to turn other things off to use the microwave and I didn't want to deal with that. So I went with 2 200Ah batteries and a 3000w inverter.
4. If you hate fire (I do too) don't skimp on the cables. I calculated that I needed 2/0 from batteries to inverter so I went with 4/0. Make sure you plan the cable routing carefully; that stuff is like bending a garden hose.

I bought some high-res system diagrams from explorist.life and they really helped me to wrap my head around what needs to connect to what and where, and what kind of wire I need.

 

[HRTKD]

The two PV panels will work with the solar charge controller in the original post. The solar charge controller has a max PV input of 100 volts. Two of those panels in series will be no more than 50 volts.

The silicone wire in your list may not be suitable if you're using it to go from the PV to the solar charge controller. Instead, you want actual PV cable that has a UL 4703 rating. I was looking at that exact cable, considering it for occasional use with ground deployed panels. I wouldn't have used it for cable that is always exposed to the sun. Another consideration that went through my mind with that cable is that the insulation may be thicker than normal cable, which would make it a tight fit for the cable gland as well as the MC4 connectors.

Everywhere else in my system I used welding cable, 6 gauge and 2/0 gauge, from TEMCo Industrial. The welding cable is very nice to work with because it is so flexible.

You have the Victron shunt in your diagram. If the extra expense isn't an issue, using Victron for everything is handy as everything gets tied together in a single app on your phone. Plus, some of the components will talk among themselves. As mentioned in another post, switch to an inverter/charger (like the Victron Multiplus) eliminates the need for a transfer switch as well as the AC-DC converter.

 

[TravelingSLO]

I should have noted - I went with a 24VDC system to lower wiring sizes and to take advantage of better solar performance, lower losses, etc.

Wow! Looks excellent! I read quite a bit about a 24V system, but decided that it would be simpler (in my own head, possibly not reality) to do the 12V setup. Also, this, like all projects started out very small, and then, it grew. Thanks so much for sharing your plan, I've downloaded it so I can inspect it more closely - and I look forward to checking out the link you posted!

 

[TravelingSLO]

I'm in a somewhat similar situation as you, and I'm in the middle of building a similar system (2x 200w panels, 2x 200Ah lithium, inverter). Here are a few choices I made:
1. For me, the hard limiting factor to boondocking endurance isn't electrical, it's water. My trailer has 30 gallons of fresh water and a 30 gallon grey tank. Our initial camping experiences taught us that we use about 5 gallons per day, so 6 days is about the limit no matter how many batteries or panels we have.

Yes, me as well. We actually use fairly little power (we cook using the propane and we have a propane oven, and it is rather efficient). The water is the hitch, and I love our toilet and don't want to be toting pee everywhere (my best friend has a composting toilet they love, converted their black tank into a grey tank, and added additional fresh water storage, and don't find it a problem - they can stay out much longer). We don't mind moving every five days or so anyhow.

2. I was willing to spend more to hook up less stuff. After pricing out a decent inverter, a good battery charger, and an automatic transfer switch, I was within a couple hundred bucks of a really nice name brand inverter/charger/ATS. I bought a Xantrex XC 3000. Much easier to hook up and only one box to mount instead of 3.

I didn't initially mind the idea of hooking more stuff up - but when I think on it after reading these messages, it IS one more thing to break. I'll run additional numbers and see if the inverter/charger is possible for me. They just seemed SO expensive, and in reading Will's book and watching the reviews, it just seemed like I could cobble something more affordable together, but maybe that was dumb based on my experience level.

3. With the inverter & batteries, I wanted to be able to power the microwave/convection oven, the AC-powered TV (although it's a small one that doesn't use much power), and use all the lights and 12-volt stuff. A 200Ah lithium battery and 2000w inverter was going to be marginal so I might need to turn other things off to use the microwave and I didn't want to deal with that. So I went with 2 200Ah batteries and a 3000w inverter.

We never use the microwave. But I do have a toaster which I am fond of, and it runs around 1200 watts, but we only use it for a couple of minutes every few days. So, more power is probably better. But it means more money. Have to decide which is more important to me.

4. If you hate fire (I do too) don't skimp on the cables. I calculated that I needed 2/0 from batteries to inverter so I went with 4/0. Make sure you plan the cable routing carefully; that stuff is like bending a garden hose.

I bought some high-res system diagrams from explorist.life and they really helped me to wrap my head around what needs to connect to what and where, and what kind of wire I need.

I'm totally checking them out! And I'm happy to read you went a size larger with the batteries to inverter cables - that was one of my big questions. Thanks so much for sharing! This really helps! Good luck with your build! Maybe we will all run into one another in a campground somewhere - or a forest!

 

[TravelingSLO]

The two PV panels will work with the solar charge controller in the original post. The solar charge controller has a max PV input of 100 volts. Two of those panels in series will be no more than 50 volts.

Hah, we spent hours last night trying to figure that out. Glad to hear it. I was *really* worried that I had totally misunderstood how this all works.

The silicone wire in your list may not be suitable if you're using it to go from the PV to the solar charge controller. Instead, you want actual PV cable that has a UL 4703 rating. I was looking at that exact cable, considering it for occasional use with ground deployed panels. I wouldn't have used it for cable that is always exposed to the sun. Another consideration that went through my mind with that cable is that the insulation may be thicker than normal cable, which would make it a tight fit for the cable gland as well as the MC4 connectors.

Thanks for the tips on the wire - I will check that out.

Everywhere else in my system I used welding cable, 6 gauge and 2/0 gauge, from TEMCo Industrial. The welding cable is very nice to work with because it is so flexible.

You have the Victron shunt in your diagram. If the extra expense isn't an issue, using Victron for everything is handy as everything gets tied together in a single app on your phone. Plus, some of the components will talk among themselves. As mentioned in another post, switch to an inverter/charger (like the Victron Multiplus) eliminates the need for a transfer switch as well as the AC-DC converter.

I was trying to keep the price down, but if it comes at the expense of safety, it's not worth it to me - and as others mentioned, I will look into that inverter/charger option. I didn't know about the transfer switch when I first drew up those plans. Thanks again! This was all very helpful, I appreciate it!

 

[TravelingSLO]

Some ideas to add:

• You might want to bump your 2200w inverter to 3000w if you really are going to run some larger things like a microwave and A/C. Better to have some more head room especially with a high frequency inverter. Both these inverters would push more then the 100A discharge a single SOK battery is rated for. I would suggest bumping up to two to run a 2200w or 3000w inverter. I have other reasons to add a second battery farther down the list.

We've not needed the A/C or the microwave a lot (we tend to travel in the fall), but if we had more flexibility with batteries, maybe we would have more flexibility with locations? Good to think about!

• You can keep the WFCO 8900 but make sure the converter can support LiFePO4 charging. You can buy a separate converter/charger and still keep the WFCO for distribution if it doesn't.

• If you want the inverter to supply all the outlets with power when your not on the grid you need some sort of transfer/change over switch to switch the AC input between the shore and inverter power. You also want to make sure your converter doesn't try to charge your batteries while your running on your inverter. I don't see any of the AC wiring in your diagram yet. If your just going to use the outlets on the inverter then its not an issue but that will make running things like your microwave hard since you like don't have access to the plug. A changeover switch (search "change over switch" on amazon) might be a cheap option to switch between sources and could also be used to only connect the converter when connected to shore power.

Heh, yah, the wiring part - I needed to work more on that. Luckily some helpful folks posted theirs, so I am going to do more homework tonight figuring out how to make this even better. Wiring seems like step 1, not much will work without that. ?

• You can also try to keep more things on DC. Both your laptop and phones can run off DC vs using the AC adapter just to convert back to DC. I like to add 12v power outlets that you can use car chargers in. As the USB/charging standards change and advance you just swap a charger. There are some USB chargers that can put out plenty of power for a laptop or phone.

My partner is very interested in the DC options for running the laptops - he said that they all start as DC anyhow because the laptop has a battery, so that little brick is what's making the laptop juice into DC - I will totally check out those chargers. I didn't want to fry any of our electronics, but I am glad to read that you think it's possible.

• Ignore the prewired for solar zamp stuff it is just a wire running to your batttery box
• If you can afford it another SOK battery will make you very happy especially if you have a 12v compressor fridge. With only 200ah your going to only get maybe a hour of A/C run time when factoring other loads in. If you plan is to run it before bed that doesnt work well because you wont have juice left for the night. You will need another SOK to have any real use of the A/C in my opinion. I have 600ah and I still get "range" anxiety when running my A/C.
• Think about your breakaway system. There is some disagreement about tying your breakaway system to you lithium batteries. I suggest getting a inexpensive dedicated breakaway battery and leaving both systems totally separate.

I recently posted my RV build which has a schematic of all the connections and fuses and what not if it is helpful.

SO HELPFUL! Thanks to you, and everyone else on here who's posted other builds. I honestly believe I can do this once I get the right parts assembled.

 

[HighTechLab]

I'm watching, looks like everything I was going to mention about this system has been said, so for now I will continue to monitor and jump in if specific questions come up.

 

[Mattb4]

What is the results of the energy audit you did? Understand that using solar/battery versus grid or generator that ratings are not what you actually get. You need to allow for all the losses. So as example your energy audit shows need of 500wh per day. Your system will likely need to be able to develop at least 3-4 times that in order to account for losses, loads and return to a state where you can start the next day without being already partially depleted. Thus 1500 to 2000wh. Does your design incorporate all of this? If not than every day you have to subtract from your battery the amount you do not meet full restore capacity from solar. This will give you run time until a generator or shore power becomes available.

A 206ah 12v battery is able to deliver 10.3 amps for 20 hours before completely discharged (10.3 *12= 123.6 watts per hour for 20 hours). Or it can deliver ~2400 watts in 1 hour before dead.

ETA: There is also one other factor that I forgot to mention. Your panels might be sufficient to recharge your battery and supply loads during the peak of the day. However any additional power they could supply is lost once your batteries become charged. The panels no longer see the battery as loads. Amount of storage and amount of generation for loads is a strange dynamic.

 

[TravelingSLO]

This comment is so incredibly helpful. Thank you for taking the time to write it. I knew there was some loss, but I didn't know these specifics. I recognize that the information is out there, but sequencing it all into something that makes sense to me is proving to be the difficult part. How do people learn this stuff? Are they engineers? Did they learn these things by doing and reading the manuals? Is there a useful book out there? Clearly they use the handy wiki and FAQ located here on DIY Solar.

I've been relying on YouTube and blog posts and informational posts made by Victron and other companies (which are surprisingly helpful and well written!) but I am so far from understanding the nuances of this it makes my eyes cross.

What is the results of the energy audit you did? Understand that using solar/battery versus grid or generator that ratings are not what you actually get. You need to allow for all the losses. So as example your energy audit shows need of 500wh per day. Your system will likely need to be able to develop at least 3-4 times that in order to account for losses, loads and return to a state where you can start the next day without being already partially depleted. Thus 1500 to 2000wh. Does your design incorporate all of this? If not than every day you have to subtract from your battery the amount you do not meet full restore capacity from solar. This will give you run time until a generator or shore power becomes available.

My design totally does NOT incorporate all of this! This is fascinating and very informative.

We own a generator. My current plan is that if we *need* A/C or a heavy load item, then we are running the generator.

A 206ah 12v battery is able to deliver 10.3 amps for 20 hours before completely discharged (10.3 *12= 123.6 watts per hour for 20 hours). Or it can deliver ~2400 watts in 1 hour before dead.

ETA: There is also one other factor that I forgot to mention. Your panels might be sufficient to recharge your battery and supply loads during the peak of the day. However any additional power they could supply is lost once your batteries become charged. The panels no longer see the battery as loads. Amount of storage and amount of generation for loads is a strange dynamic.

That fact about storage vs. generation is really interesting and I am going to keep it in mind.

After a long discussion with my partner, we have decided that we need the RV solar system and battery bank to be able to keep the wifi router, laptops and phones, and basic RV equipment including the Dometic DM2672 refrigerator (it runs on propane but requires DC to keep the fan and other electronics going). We need to rein in the budget somewhat. So upgrading to the amazing builds that some others have kindly shared will have to wait for us.

Here's a screenshot of the energy audit. It's like all the things we regularly use, but some use could be cut back to conserve. I currently have one SOK 206Ah battery, and two 200W Rich Solar panels. I'm still trying to figure out the rest of my plan based on feedback from here. I think I will get a second battery. There have been many suggestions for ditching the stuff I already bought and getting an inverter/charger, but the cost on those is either high/good reviews, or low/bad reviews/warranty issues. So I am mulling over my options presently.

 

[SniperX]

I took a stab at editing an existing diagram I had and inserting your components.

View attachment 103491

This is like a masterpiece to my eyes... I am searching this topic too. VERY NICE.

 

[mccollums]

This comment is so incredibly helpful. Thank you for taking the time to write it. I knew there was some loss, but I didn't know these specifics. I recognize that the information is out there, but sequencing it all into something that makes sense to me is proving to be the difficult part. How do people learn this stuff? Are they engineers? Did they learn these things by doing and reading the manuals? Is there a useful book out there? Clearly they use the handy wiki and FAQ located here on DIY Solar.

I've been relying on YouTube and blog posts and informational posts made by Victron and other companies (which are surprisingly helpful and well written!) but I am so far from understanding the nuances of this it makes my eyes cross.

My design totally does NOT incorporate all of this! This is fascinating and very informative.

We own a generator. My current plan is that if we *need* A/C or a heavy load item, then we are running the generator.

That fact about storage vs. generation is really interesting and I am going to keep it in mind.

After a long discussion with my partner, we have decided that we need the RV solar system and battery bank to be able to keep the wifi router, laptops and phones, and basic RV equipment including the Dometic DM2672 refrigerator (it runs on propane but requires DC to keep the fan and other electronics going). We need to rein in the budget somewhat. So upgrading to the amazing builds that some others have kindly shared will have to wait for us.

Here's a screenshot of the energy audit. It's like all the things we regularly use, but some use could be cut back to conserve. I currently have one SOK 206Ah battery, and two 200W Rich Solar panels. I'm still trying to figure out the rest of my plan based on feedback from here. I think I will get a second battery. There have been many suggestions for ditching the stuff I already bought and getting an inverter/charger, but the cost on those is either high/good reviews, or low/bad reviews/warranty issues. So I am mulling over my options presently.

View attachment 103709

Do you have enough room for the SOK server rack battery (5.12kWh)? It's cheaper to buy one of those instead of 2 SOK 206Ah batteries.

Also, wouldn't be a bad idea to buy a Bluetti EB3A when they go on sale (Black Friday or a Prime day.. they are only 209$ on sale and will charge the phones and laptop if you have any issues with your main system. Throw in a portable solar panel with usb charging and you have something you can take on hikes that will charge phones and charge the EB3 in a pinch.

I am still learning like you, and thankful you have taken time to type all this out.. I was trying to motivate myself to do that today but didn't need to after your thread. My goal, if I feel comfortable enough with DIY, is to build a portable solar generator to run a small chest freezer and mini fridge in case of an extended grid outage. I'm struggling with the inverter decision like you...they get expensive QUICK. However, I'm not in a rush and I think I'm going to watch FB Marketplace for a deal on a used inverter.