DIY Off-Grid Solar FULL Install & Wire Diagrams - Powering Our Homestead w/ the SUN!

If you're looking for a safe and reliable way to build your own massive DIY off-grid solar power system, you've come to the right place. Hey there, I'm Ashley and this is Jonathan. We're Tiny Shiny Home. Our family of six has spent many years traveling full-time in our renovated vintage Airstream before finding some off-grid property here in Cochise County, Arizona. Our dream here is to build a sustainable off-grid desert homestead using solar to create our own oasis in the desert. We'll be doing a full cost breakdown in a separate article and video, but for now we'll be focusing on the building, the installation, and the wiring of our huge off-grid solar system. Before we go any further, let's give you a high-level overview of our system. 7,200 watts of solar panels, five series, six in parallel, 28 kilowatt hours of lithium batteries, two parallel, 16 in series at 48 volts, 5,000 watt inverter, single phase at 120 volts, surges to 10,000 watts. This should power our Airstream, our solar shed, and eventually our house. If you get lost during this video, there is a full nerdy detailed article on our site with all this information, with links to buy everything, with wiring diagrams, it's 10,000 words, it's ridiculous. But it's full of good information, so make sure you go check out this site below. Disclaimer, I'm not an electrician, nor do I play one on YouTube. All information here is solely for entertainment purposes and all electrical work should be performed by qualified individuals according to local electric codes. Cool? Cool. Also yes, you will hear roosters in the background. We live on a farm. Are you a visual person like me? Do you just want to like see all this laid out in excruciating detail without having to watch 30 minutes or read 10,000 words? Well, you're in luck because I made a wiring diagram of our entire setup. You can zoom in on it as close as you want in high-res glory. You can buy it from our site right now. Before we get started, we have to mention that this solar power install was part of a much larger project, which you can see right behind me. This is our Earthbag solar shed office. This was a great way for us as a family to build naturally and sustainably and try out a ton of natural building techniques. It was so much work, but it turned out so good. It doubles as an office and a guest room, but it also has all that power gear inside. Setting up an independent off-grid solar system was a huge part of our infrastructure out here on our homestead. We're excited to share this power setup with you because we think we found a great way to create a large... We're excited to share this power setup with you because we think we found an incredibly cost-effective way to make a massive, safe, reliable off-grid solar power system. Now, babe, could we have built... Oh, I'm not going to talk to you. Sorry. Now, could we have just hooked up to the grid? Sure. It's about a half mile away to the nearest pole. We could have done that for about $35,000. That's crazy. But do we want to do that? No. We want to be off-grid and sustainable. That's kind of the whole point of why we moved out here. But it turns out that we were able to build our own system for way less than that. Oh yeah. So it totally worked out anyway. Now, we do have to talk about our power goals because that's going to be different for everybody, right? Right. We came from a background of traveling full-time in our Airstream and most of that time we were off-grid and boondocking, so we're already pretty used to being low power, low energy. Not low energy, but like we're not using a lot of energy, right? Yeah. From a high-level overview, we knew we wanted to go with a 48 volt battery system because the conversion from 48 to 120 volts is much better than a 12 or 24 volt. We also knew that we didn't need 220. Now, that might be controversial, but we have been used to living off-grid low power for such a long time that we decided to stay at 120. We decided we did need a dryer. Now, okay, some of you are going to say, why does she not want a dryer? We live in Arizona. Most of the year it's sunny and if for some reason I can't dry things outside, I'll just run to the laundromat and dry it real fast. But the plan is to just hang all of our laundry out on the line. Yeah, low humidity helps a lot. For cooking and heating, we do have a mini split that uses very little power for heating, but otherwise we're going to supplement with like gas, propane, wood. There's much more efficient ways to heat than to just run electricity to everything. Also, we're building all of our buildings with hybrid adobe earthbags, which means we are creating thermal mass and taking advantage of passive solar. And should we ever decide to change our minds and say, well, maybe we do actually need 220 volts, or we've wired and So that means I might get a dryer. Maybe one day. Okay. All right, enough of this overview stuff. Let's get to it. First thing, solar ground. The first question I know you're going to ask is, why did you build this huge solar panel array and why didn't you just put your solar panels on the roof of your solar shed? It's a good question. The reason for that is that we built this to take advantage of passive solar. That means that there's clear story windows facing south that let the sun come in in the winter, but then there's an overhang. So in the summer, those windows are shaded and the roof is slanted north. So that means we can't put solar panels on that roof because it's totally facing the wrong way. You need to be facing south in our case, preferably at about 30 degrees. So we had to build a solar ground. Our first step to saving money on this install was solar panels. So here's the thing. Solar panels get installed in residential and commercial installations, but then often they're replaced every couple of years due to contracts. They still work totally fine, but thankfully there's a company called Santan Solar. They buy these panels, they recertify them, and then they sell them back to you at a fraction of the cost. So we took advantage of their yearly sidewalk sale and bought 30 of these 240 watt residential panels for only $25 apiece. That means we got 7,200 watts of solar for less than $800. That's crazy. Now it turns out that was actually the smallest expense in related to our solar panels because we still had to build a ground mount. And that is what we're going to talk about next. This solar ground mount ended up being a massive project in and of itself. There was so much research to do and so many things to plan for. First was that we needed to make sure that these panels were going to be as efficient as possible. So there's a couple of online calculators you can use to tell you how to tilt them and then which way to point them. In our case it was 30 degrees and then 10 degrees east of south. We live in the high desert of southeast Arizona which means that we get insane monsoons and weather events and even a little bit of snow. So we had to engineer this thing to withstand 100 mile an hour plus winds in very sandy soil conditions. That means we look to the experts to help us figure this out because this is way too much to figure out on your own. Thankfully there's a company called Iron Ridge and they make a lot of the components that allow you to attach the solar panels to your frame. They also have an online assistant tool that will do so much of this work for you. They'll help you figure out exactly how much pipe you need, how much cement you need, how to cut everything, what your angles should be. They provide full drawings that can even help you get permitted if that's something that you have to worry about for your local codes. So let's start with the Iron Ridge components that you're going to need. Top caps, rails, rail connectors, UFO or universal fit object module and stopper sleeves, end caps and wire clips, and a grounding line. While we were able to directly order those items from Iron Ridge we had to source other items like the three inch schedule 40 pipe, a ton of cinder blocks, a bunch of cement, all ourselves. Using the diagrams provided by Iron Ridge we picked this spot for our solar array because it's about 100 feet to the solar shed and we didn't want to run any heavier gauge wire longer than we had to. We started by augering the eight holes that were five and a half feet deep by two feet wide. Then we had to cut our steel pipe because the pipe only came in 20 foot segments and our entire array is over 32 feet. We had to do all that math and figure out how to cut the legs to go down in the holes and then also how to split the long ones so that they landed right on top of a pier and were connected by a top cap. It's kind of confusing. Here's a picture. And again I have to give a shout out to the Iron Ridge design assistant tool because it helped us know exactly how long to cut all these pieces of pipe. Once the holes were dug it was time to use the stacks of cinder blocks and jacks to get the horizontal rails in place both parallel with each other and leveled horizontally. As you can imagine lining all this up took a while and we had to readjust many times. Once these were in place it was just a matter of attaching the vertical piers via Iron Ridge's top caps letting them hang in the holes and then filling with cement. Not that this was easy we're talking like 200 plus bags of cement. By the time we got finished none of us ever wanted to see a bag of cement again. With the frame in place it was time to add the rails which are the heart of the Iron Ridge system. We went with the XR1000 because they're rated for higher wind and heavier snow loads and all that stuff and because of the way we were setting up our solar panels we needed 12 rails total one on each side of the array. So here's a close-up of how these components work. This is the top cap so your pipe is going to slide up inside there and then you tighten it up to hold it in place. It uses the U-bolt to go over and attach to this one and then you tighten it up. The rails are then connected to the pipe via a rail connector which is sort of a an L bracket that uses the U-bolt and then slides into the track and then it can slide up and down and move exactly where it needs to and then you can tighten it into place. One thing we realized using this system is how forgiving it is. We were like super worried about making sure everything was like perfectly lined up but it turns out that because everything can move every which way it's a lot more forgiving than we thought it was and it made it much easier to install. The next step is that you're going to use what are called UFOs or universal fit objects. These go into the rail there's a little track on top of the rail that will slide into and then the panel will set down on that and then you tighten it up and it clamps it down. To start your panel array you have to use a stopper sleeve on the UFO to give it a flat surface to set against. Then it's just a matter of setting new panels in with UFOs in each track all the way up. One final thing about the Iron Ridge system is that everything should be torqued to exact specs so make sure you have both a foot-pound and an inch-pound torque wrench. With the ground mount built and the panels attached it was time to turn our attention to wire. We already decided that we wanted to run these five in series so we could jack the voltage up keep the amps low and then keep our wire runs a smaller gauge going from the array into the solar shed. Also by creating high voltage arrays we were able to pull in more power earlier in the day later in the day and when it's cloudy. Here's how the math worked out. Each 240 watt solar panel array connected five in series produced 1200 watts 186 volts and eight amps. Then connecting all six arrays in parallel created a 7200 watt 186 volt 50 amp solar panel system. From a physical connection standpoint connecting in series means that you take the positive from one panel and connect it to the negative of the next panel and then you do that all the way down but then you have one at the end that you're going to have to run back into your combiner box. So we had to do a bunch of math and a bunch of measuring and then buy a bunch of pv wire and mc4 connectors and extend and create our own wires to make this all work. In order to get all of our wires into our combiner box we had to buy 300 feet of solar wire and 24 mc4 connectors. With each series of five panels we needed to connect in parallel and so that's what this combiner box does. You can see this one has four inputs so we have four of our five panel arrays on this one and then two on the other one and also that means that we have room to expand on that other box if we ever want to add ones. The other important thing we needed as part of this install was a lightning arrester. We hadn't heard of this until we moved out into the wide open spaces of the desert but apparently indirect lightning strikes are a thing out here and so just in case this ground mount were to ever get hit by lightning it would run through this lightning arrester it would run to the copper ground rods that we have installed it would trip and none of that surge would ever go into the solar shed where all of our gear is. The other cool thing about this box is that it's already pre-wired for you so all you have to do to make up your mc4 connections connect them into the bottom and then run your pv wire up and connect it here and all this is already taken care of. Honestly I think the hardest part of all this was figuring out how to mount these boxes to the steel pipe. We used some unistrut and a bunch of plywood and it's super janky but hey it's on there and it works. Next up is trenching. Now obviously everyone's trenching situation is going to be very different. Like we mentioned we had to run a little over a hundred feet from this array to the solar shed so what we did is we took the positive and negative wire coming out of each of these we ran it up through a service entrance goes down into the ground all the way over and then through some lb connections on the outside of the solar shed. Because of the length of the run and the amperage we use six gauge wire which will actually allow us to increase our panels if we ever need to but this ran through one and a half inch conduit through multiple twists and turns and we dug it all by hand and it was ridiculous but we got it done. Now one last cool thing about this iron ridge system is a grounding. Grounding is very important you're putting a ton of power through this system so the neat thing is that the way the iron ridge ground mount is designed is that all the metal is all touching each other so the system is grounded by itself but they also give you a grounding lug connection that connects to the frame and you run a bare copper wire to an eight foot ground rod. We also wanted to make sure that with our lightning arresters they also need to run to a ground rod. So what we did is we put two ground rods in but one here for the iron ridge actual array and then we put one in here that the lightning arresters connect to and then we connected it all together just in case because hey lightning sucks. Another big part of how we saved money during this solar install was batteries. Now there are so many different ways to build a large battery bank now but I think we've reached the point where lithium batteries are definitely the best choice for a large bank that you want to last for a long time. Lead acid or AGM batteries are going to be bigger and heavier you're only going to get half the capacity they're going to have voltage sag when they get high draws on them but lithiums will be smaller and lighter they don't have to be vented they don't have any voltage sag and you can charge them quickly. They're just much much better overall and with lithium batteries running at 2,000 to 3,000 cycles they could totally last 15 to 20 years which is crazy. The one downside to lithium is that they need a brain or a BMS to help manage voltage and temperature and balancing but overall if you're going to invest this much money into a large battery bank that's going to run your entire property the BMS is totally worth the investment. So these are the main options for lithium batteries on the market right now. Tesla sells its Powerwall which is a battery pack inverter and charger all-in-one. You can get used electric car batteries like the Chevy Volt and the Nissan Leaf. Rack mounted 48 volt systems like the LifePower EG4 and of course everyone's getting into the lithium cell game with companies like Battleborn that have a BMS built into each battery. There are some issues with each of these though. Powerwalls are crazy expensive about $500 per kilowatt hour. Battleborns are also ridiculously expensive at about $720 per kilowatt hour and the built-in BMS doesn't interface well if you have more than one. The rack mounted systems are a little bit cheaper around $300 per kilowatt hour and electric car battery prices are all over the place from $170 to $300 per kilowatt hour but they're difficult to source and they come in hard to open housings with lots of voltage and setup quirks. What if you could buy small efficient easy to connect cells to build your own battery bank at a fraction of the cost? Enter Alibaba. So here's the thing other than Tesla every single one of those battery cells I mentioned they're all made in China so maybe you should just buy your batteries directly from China anyway. Recently there's been a surge in competition for these types of cells if you go to Alibaba and you type in 280 amp hour lithium battery pack you will get thousands of results. In fact we only spent $130 per kilowatt hour for our 28 kilowatt hour battery bank. It was about $3,800 and that was in the middle of COVID when the prices went crazy high so they could even be lower now. The Tesla or Battleborn options would have cost us five to seven times for the amount of storage. You just have to assemble the packs yourself and we'll get to that in a minute. Now before I get too excited about Alibaba and saving tons of money on lithium batteries I have to tell you a story. So settle in we're going to recount the saga of buying batteries from Alibaba and having them shipped directly from China. Our story begins with a search. Like I said searching for a 280 amp hour grade A lithium cell on Alibaba gets you a lot of results. So I reached out to a few suppliers to get estimates. Things started out well. The representatives were asking important questions like what voltage battery bank are you building? Are you buying the right amount? How are you going to use it? What's the application? They all got me estimates and we picked one that seemed like a pretty good price and then that's when things started to get weird. I tried to pay for the order with a credit card and it was declined not by my credit card company but by Alibaba. And then because Alibaba had deemed my credit card dangerous I couldn't pay with any credit cards for anything. So I was left with like PayPal and Western Union as a way to pay which felt super sketchy. I didn't want to do Western Union so I ended up doing PayPal and I went through okay finally first hurdle we're past it. Then like two days later I get an email and they're like hey those cells you ordered we actually don't have them in stock even though they told me that they did. We would like to give you a different battery that's more capacity for the same price because we're going to keep our word but here's the thing it wasn't the same cell. So if you've looked into buying these batteries online you may have run across a few acronyms. There's EVE, REPT and a few other ones but the the main thing is that EVE cells have been around a lot longer and there's just a lot more sort of anecdotal data out there that we can use to see that they do last a long time and they are what they say they are. However they were out of the EVE cells and they wanted to send me REPT which is kind of like a newer kid on the block and there's not that much information about them. So I was like I'd really like the ones I paid for and they said well it's going to be six months before we get some in. We were in the middle of COVID, all the shipping ports were backing up. We really needed to get these batteries here in stock so I went ahead with the REPT and just kind of dealt with it and I figured well you know they're so cheap if they really don't work out then we'll just get something else. Now one thing I should mention is that you have to really plan ahead for these because it does take a couple of months for these to actually make it from China going over the sea and then come to you. There were definitely a few points during this process where I started to worry if I got scammed because when they shipped them they gave me a bunch of FedEx tracking numbers that never really updated. They just said pending the entire time and I would ask them for some sort of update on shipping and they would send me shipping manifests completely in Chinese. It didn't really help me and then they're like well it's in port but the ports are backed up and then they're like well now it's in customs and it could be like a week or a month and we waited and we waited and we waited and then all of a sudden two and a half months later FedEx showed up with eight huge boxes and that FedEx tracking number still never updated it still says pending to this day. So all I have to say if you're willing to wait a little bit longer and do your research you can get a large lithium battery bank for a fraction of the cost. Also several other YouTubers have had issues trying to buy battery cells like this and instead of getting grade A cells they end up with grade B which have some problems with swelling or maybe they don't have the full capacity ratings but I got a few tips here to help you avoid that. Try going through Alibaba instead of AliExpress. Stick to well-known cell names like EVE or REPT. Get quotes from multiple suppliers and avoid any prices that seem too good to be true. If you're curious we bought ourselves from this company and this is the exact listing. The good news is our batteries were all packaged very securely, no swelling, perfectly top balanced and we can't say a bad thing about. Now let's head inside and look at exactly how we built this battery bank. While using these small compact cells made it easier to build our own battery bank that's not to say it wasn't difficult. Building something safe and secure for a battery bank this big is still hard to do. First we had to decide how we were going to connect them together. Batteries connected in series means that their voltages are added together. The batteries wired in parallel means their amp hours are added together. We knew that we needed a 48 volt system. We also knew that our BMS was going to have 16 inputs so really it was just a matter of doing a bunch of math. We could have bought 16 of the 3.2 volt battery cells, connected them all in series and created a 48 volt system because 3.2 volts times 16 equals 51.2 volts. But that only would have been about 14 kilowatt hours of storage. The way you figure that out is you take the amp hour of each cell and multiply it times the volts so 280 amp hours times about 50 volts gives you 14 kilowatt hours. Now that's a decent amount of storage but because we're building this for our entire homestead we knew we needed more. Simplest way to get more was just to double the amount of batteries. So we bought 32 batteries, grouped them together in packs of two via parallel connection and then connected each pack of two in series to create a 28 kilowatt hour battery bank instead. The batteries shipped with some really flimsy bus bars and nuts and washers but we opted to go get our own copper bar stock and basically redo those connections to get our maximum flow through. Before we could connect anything though we had to build a battery box to keep all these batteries in. We had to decide which way to configure them because really they're best connected end to end in a series configuration but we didn't have that much room in this little power corner of our solar shed. So we basically took 16 and then another 16 and stacked them on top of each other. Lithium batteries need to be compressed so that they don't swell over time so what we did is we took some thick plywood, some long pieces of all thread rod, some heavy duty nuts and washers and we basically put two pieces of wood on each end of the 16 group and then use the all thread to compress it together and hold it so that they wouldn't expand and contract during usage. Then we welded a metal frame to hold each group of 16 batteries. Each cell weighs about 11 and a half pounds so a full row of 16 weighed almost 200 pounds. Huge shout out and thanks to Juan and Michelle from beginning from this morning. They not only helped us plan this whole system but they also brought their welding gear and helped us build this battery box. With our packs created we slid them into place and began to cut and drill holes in the copper bus bars so that we could connect everything together. Remember we were connecting two cells in parallel and then each pack of two was connected in series. This is a little confusing so here's a graphic of what it looked like. Then all we needed to do was continue that series connection from the top row to the bottom row and we did that with a large 2-watt copper welding wire. Now before we tightened the nuts down to hold the bus bars in place we did have to run our BMS wires and we'll get into the BMS install in a minute but just know that we ran a bunch of 18 gauge wires to each pack of two so that the BMS can balance and keep track of the voltage in each cell. And finally we needed to run heavy duty 2-watt wire from the positive post and the negative post of the battery into the system and we'll cover that more. Before we get into wiring the BMS I want to talk about fusing and protecting the system. With something this big with this much power flowing through it you want multiple points of protection. So I'm just going to show you real quick what we've added kind of talk about each one and show you sort of how the power flows through. So right off of the positive battery post we're going to run through a 300 amp t-class fuse. This will protect the system and the batteries it'll protect both ways if there were some sort of power surge. There's also a battery disconnect and so this is a switch that will cut off any power from the batteries if you need to do any maintenance or anything like that. After the switch you're going to run through your contactor so everything on this side of the contactor is always going to have power unless this blows or you turn this off but everything on this side of the contactor will only have power if the BMS says it's okay for it to and so it's checking for voltage and temperature and all sorts of things. The last major part of the 120 volt side is that you're going to have power coming from that contactor into your inverter but first it's going to flow through a circuit breaker. This is a 200 amp circuit breaker. Again we can flip this off if we want to shut power off to the inverter but it also protects the system if the inverter decides to go haywire and so that way power doesn't flow back through the system. And then finally from the negative post on the battery you're going to run through your current sensing shunt which is also connected to the inverter and it looks for state of charge. One important note when you're installing any of these circuit breakers or switches or fuses they should all either be removed or turned off while you're installing until you're ready to boot the system. I can't overstate how important a BMS or battery management system is to a large battery bank like this. You have to protect these cells from overcharging, undercharging, from temperature extremes. You have to make sure that they're balanced properly or that 15 to 20 year reference that I gave you earlier isn't going to hold up because they're going to die way too early. Here's everything that a good BMS should do. Overvoltage. Overcharging the batteries can be very dangerous and cause swelling or fires. The BMS constantly checks for high voltage and shuts off the system if needed. Undervoltage. Batteries that have discharged too low can also be permanently damaged if tried to use during that state. The BMS checks for low voltage and will shut off the system until it reaches a safe threshold. High temperatures. The stability of lithium battery cells depends on keeping them within their operating temperatures. If you're charging them while they're too hot this could lead to a fire. Low temperatures. Lithium batteries will be damaged if you try to charge them and their internal temperature is below 32 degrees. So the BMS checks for cell temperature and shuts down the charging aspect if needed. Charge, float, and hysteresis. A good BMS will let you set these parameters so that overvoltage and temperature issues never happen in the first place. The BMS should talk to your charge controller and help fill and float the system safely. Keeping all your cells near the same voltages will drastically increase their life. A good BMS should be able to equalize or balance all the cell's voltages by diverting some current from higher voltage cells to the whole pack or the whole pack to a lower voltage cell. Trying to run a large off-grid battery bank without a BMS is asking for all sorts of problems. You're going to reduce the life of the battery, reduce return on investment, and possibly start a fire. So spend the extra cash and get a good BMS for your batteries. What BMS should you get? It's a great question. We chose REC BMS for these reasons. They have a great reputation for stability and customization and are very knowledgeable of using batteries off-grid. Their support is fantastic and very technically detailed. Their products can talk natively to Victron gear using the proprietary Victron VECAN protocol. This was important for setting both charge controllers and the color control GX, which is the heart of our monitoring system. Deep level settings are accessible via their new Wi-Fi module so you don't have to connect a computer to make updates. It measures battery temperatures via probes but also has an internal temperature for the unit itself. This plays real-time info at the cell level on its own touch screen. It can be configured with a pre-charge delay which should prolong the life of your equipment by sending a trickle charge to components so that they don't get hit with a large inrush of current and measures using a precision shunt resistor. This gives a very accurate state of charge percentage. You may be wondering why we didn't opt for a built-in BMS. We mentioned earlier some batteries come with built-in BMSs but here's the problem with that. Not only does it inflate the cost but it means that many of the sensors and the elements are all proprietary and they're all enclosed where you can't really get to them. So in our case if a temperature sensor ever goes bad, if a voltage wire ever goes bad, those are easy to replace. We can do it ourselves and that's much better for long-term maintenance. This is our recommended shopping list for REC BMS components. The REC-Q BMS-16S which is the main unit, current sensing shunt, temperature sensors, pre-charge resistor delay, Wi-Fi module, LCD touch display, your cable for Victron VE CAN, your contactor, and your current sensor harness. Now in our article we have affiliate links to all the REC components but I did want to give you a heads up. If you go to the link for the actual BMS unit, there you can actually add almost all of these other elements as part of a package and you save like five percent for each thing. So make sure you do it that way if you're going to build your own system. As much as we love our REC BMS, it was by far the most complicated part of the install. So I'm going to walk you through every single wire, every single connection, and show you how it all works together. Now we're going to walk through in order step by step each thing that we're going to connect to the BMS. This is very technical so I'm not going to be on screen a lot here but we are going to show up close video of each connection and also refer to our wiring diagram. Step one, turn off the BMS and pull the cell wiring harness out and start running individual wires from each battery cell to the corresponding number. We use small 18 gauge wire. One end will go into the screw terminal and the other we crimped on a ring terminal to go on the positive post of the cell. Keep in mind that the first input on the harness actually goes to your negative connection on the battery. Then you connect to all the positives in order and do not plug this wiring harness in until later. Remember how we grouped our batteries in packs of two? This was so we would have 16 cells which happens to be the exact number of inputs that the RECQ BMS has. Wiring up 16 cells will take some time but this is an important step in letting the BMS know exactly what the cell voltage is of each battery cell as well as enabling that important balancing feature that we'll need to maintain the batteries. Step two, now it's time to connect your VE CAN bus cable from the BMS to the Victron Color Control GX. This allows the BMS to talk natively to the central hub of your power system. The next one gets a little complicated. It can go directly to your LCD touch display. This touch screen gives you all sorts of useful info like your state of charge, cell temperatures, and voltage or you can connect it through the REC Wi-Fi module. Now we highly recommend getting the Wi-Fi module for these reasons. Number one, if you don't have it you have to buy some PC software, use a special cable, go through a Windows driver installation setup, and because it uses your RS-485 port that means anytime you want to use it you have to disconnect your display. Here we only use Mac so having to buy a PC to do this would just be a huge pain in the butt. The Wi-Fi module stays connected all the time and is easily accessible from any device via a Wi-Fi connection. You can still get access to the full programming features of the BMS but in a much simpler and easier to use web version of the application. You can also choose to connect it to your existing Wi-Fi network so that any device can quickly connect at any time without needing to connect directly to the Wi-Fi unit. You'll likely be doing a lot of tweaking to the settings in the beginning as well as monitoring so being able to do this on any device is incredibly convenient. By the time you buy the PC software and cable you're halfway to the cost of the Wi-Fi module anyway so it's totally worth the extra upgrade. So yes, we recommend getting the Wi-Fi module. That means that the RS-485 port on the BMS goes to the Wi-Fi module's main communication port. Note that there are small positive and negative wires coming out of this cable that need to be connected to your main positive and negative post. Step four. Use the Wi-Fi module's display cable to connect to the REC BMS display. This also has negative and positive wires that need to connect to your main positive and negative post. Step five is temperature sensors. This cable comes with three sensors attached. Just screw into the BMS and then place the sensors where you like on your batteries with some tape. Step six. The current sensor wire will connect directly to the positive and negative input screws on the top of your shunt. This provides an accurate system state of charge back to the BMS. Remember that the positive side of the shunt is where your battery negative connects and the negative side of the shunt is for everything else. Moving on we have the output wiring harness. Again, make all connections with this unplugged. You'll plug everything back in later in a certain order. Step seven. Now we mentioned the pre-charge unit above. If you're wondering exactly what this does, I'm just going to read it to you. It charges the input capacitors of the system components before the main contactor switches on which eliminates high inrush currents at the switch on of the contactor and prolongs the contactor lifespan dramatically. For the BMS wiring harness you only have two connections. One that goes straight to the battery side of your contactor and one that goes to the BMS input positive on the pre-charge unit. The rest of the pre-charge connections are pretty self-explanatory. System plus goes to the system side of your contactor. Battery plus goes to the battery side of your contactor. System negative goes to the negative side of your shunt. Contactor positive goes to the positive contactor wire. Contactor negative goes to the negative contactor. Yeah, like I said, it's a lot of wires. But hey, now you know how to hook it up. So let's look at the Victron ColorControl GX. The Victron ColorControl GX is the heart of your monitoring system. It's going to give live info at a glance. Everything is going to connect to it and with the VRM or Victron Remote Management Portal you can access your power system from anywhere in the world at any time. Wow, that's cool. Thanks, Beth. Before you fire up your system for the first time, you're going to want to make sure everything's connected to it. So let's look at all the wires. You've already connected the RAC BMS via the VE CAN bus, but in order for it to talk directly to everything, you've got a few more cables to run. To connect your inverter, use a VE bus or ethernet cable. And for the MPPT solar charge controllers, use VE direct cables. The display also needs power, so connect its positive and negative wires to the positive and negative of the system. You may need to put a Terminator plug into the second VE CAN slot. It does come with one. And if you want to run the VRM portal full-time, a USB Wi-Fi adapter will allow you to connect the display to your network. At this point, you've built out the base of your system. Now we're going to look at solar charge controllers and the inverter in a minute, but for now let's look at the process for booting it up for the first time. Number one, plug in the outputs wire harness on the BMS. Number two, plug in the cell wire harness on the BMS. Number three, turn on your battery disconnect switch. Number four, turn on the BMS. You'll see a red light. At this point, the BMS is going to run a bunch of checks. After seven seconds, if all is well, you will hear a clunk of your contactor and the light will turn green, and that means the BMS says everything's good. Now the BMS is going to need to have all the proper settings for your specific battery type. This will pass along crucial information like load and state of charge to the ColorControl GX. If you want to see the settings that we use for our specific batteries, make sure you go and check out the article. I've got everything in there. But of course, always send your specific schematics to REC and ask them to help you set up your settings exactly. We still need to adjust some settings for the Victron ColorControl GX so that the Victron unit can read from the BMS. I'm not going to go through all those here, just make sure you go to our article. We've got them all listed out. If you've connected everything properly, you should see the same state of charge numbers on the REC BMS display and the Victron ColorControl GX display because now they're talking to each other. Keep in mind that most systems are going to treat a battery pack as 50% by default until it has been charged to a full 100%. So if you aren't seeing the numbers you expect there, just give it some time until it's been fully charged. If you haven't already, make sure that you have power running into your inverter. This is very simple. You're just going to run a big 2-watt welding cable from the system side of your contactor into the positive end and then from the negative side of your shunt to the negative end. And of course, I should mention that our 2-watt wiring is based on our system size, how many amps and watts we're pushing through. You may need to go bigger or smaller depending on your setup. With the power run to your inverter, it's time to flip on that 200 amp pole toggle and then turn on the inverter and see if your Victron ColorControl GX changes to status of inverting and see if the inverter is actually working. Congrats! You've got power, but we're not finished yet. So what we're going to do is shut everything back down and then continue making our other connections. Number one, turn off your inverter. Number two, flip your 200 amp pole toggle. Number three, turn off the BMS. Number four, switch the battery disconnect off. At this point, you've already got your positive and negative trunk wires providing power to the inverter and you've got your Victron cable going from the inverter to the ColorControl GX, but there are still more connections we need to make. If you want to charge your batteries via a generator, you can run some wire to the AC in one connection. Then connect the other side of the wire to a 30 amp plug. Note that we're now in three-wire territory. Black is line, white is neutral, and green is ground. Also know that you'll need to adjust the charging settings of the inverter based on your generator size. We have a small 3500 watt Harbor Freight generator, but Victron is assuming we'll be using something much larger as a backup. The default input current limit is upwards of 60 amps, but our generator only puts out about 25. You're going to have to change this setting for smaller generators, but Victron does not make this easy. We had to do the dip switch dance, a very convoluted way to set your input current via tiny switches behind the top panel of the Quattro. I won't get into this here, you'll have to read the manual carefully, but once it's changed you'll see the number for input current limit updated by going to Menu, Quattro Inverter on the ColorControl GX. Supposedly you can get in and change this with a special cable and some software on your computer as well, but we haven't tried that yet. The Quattro requires all grounding cables to be connected together, so not only will the AC out need its ground connected to the ground post, the AC in, but also grounding chassis from your solar charge controllers, and from the inverter itself, which is kind of weird. That all connects to a single post, and then that post runs a bare six gauge copper wire out to another eight foot ground rod on the outside of the building. And finally we get to the whole point of this setup. Clean, stable, 120 volt power. This is as simple as running a Romex cable from the AC out into a circuit breaker box, or however it is that you need to connect your setup. In our case we ran to a main lug panel which separates the power into three connections, one for our house, one for this solar shed, and one for our Airstream. And then we have another breaker box for all the elements inside the solar shed. But hey, everyone is going to run their 120 volt or 220 volt differently, so we're not going to get into any more detail there. Let's talk solar charge controllers. Now technically you can set this up at any point during the process, we just happen to be waiting on trenching and then also a few of these elements to ship from Amazon, so we hooked these up last. So even though we have the combiner boxes back at the solar panel array with their own circuit breakers, we've added a second set of circuit breakers right here coming in. These are from the positive lines on each combiner box array. From there we ran two gauge cable from the circuit breaker into the positive PV of each one, and then also the negative lines still came through and they just go directly to the negative PV. Then out of that we're going to go through another set of circuit breakers right here. These are 100 amps each, and so the positive power from the solar charge controller is going to run through here and then down to that system side of the contactor. Then you're also going to run two gauge wire from the negative side of both solar charge controllers all the way down to your shunt. Just for reference, these are 40 amp circuit breakers and these are 100 amp circuit breakers. These provide a second layer of protection just in case whatever happens out there, those circuit breakers, maybe they didn't catch it and the power still came through. These should trip if it's over 40 amps and it shouldn't ruin these solar charge controllers. Also because we have so much solar, it means that during the day many of our appliances are running directly off of solar power anyway. So if we ever need to work on the system, just because we've flipped the battery switch disconnect doesn't mean that there's no power in the system. So we have to make sure we flip off the circuit breakers here as well and make sure there's no power flowing through Now remember we had two combiner boxes outside and so we decided to go with two charge controllers. We've oversized these on purpose again for future expandability. These are 250 volt 85 amp charge controllers so they're plenty big and we can always add more solar if we need to without having to replace them. Don't forget, like we mentioned earlier, chassis ground connections are kind of over here on the side. They're hard to see but they run from both units to the grounding lug on the end. Once all of your panels are connected and all your wires are run inside, it's time to boot up the system with your solar power for the first time. Here's the order. Number one, turn on the battery disconnect switch. Number two, turn on the BMS and wait for the contactor to turn on. Number three, flip on the breakers in the combiner boxes at the solar panel ground. Number four, turn on the 100 amp pole toggle switches going from the MPPT charge controllers to the system. Number five, turn on the 40 amp circuit breakers going from the solar panel array to the MPPT charge controllers. I should note that I actually did this backwards the first time and caused a bunch of headaches for myself. In my attempt to be extra careful, I actually left all of my circuit breakers off when turning this stuff on for the first time. These are smart solar charge controllers and when they boot up for the first time they're supposed to read the voltage of your system and set themselves properly. But because I had this switched off, it actually wasn't connected to the battery at all and it defaulted to 12 volt batteries, which is obviously not right. And so when everything turned on, I got all sorts of errors and alarms and everything went haywire and it took some time for me to figure out what happened. Thankfully these units are bluetooth enabled, so I was able to pull up an app on my phone and get in there and change the batteries to the right type of batteries and the system voltage to the right voltage. And once we got past that, then everything was good. Hey look at that! You have power. It's been a long road, but by building this yourself, you've been able to save thousands and thousands of dollars. High five. Moving forward, I want to set a few expectations. Your BMS is going to spend some time balancing your battery cells. They're not going to be perfect right out of the gate. In fact, they may overheat, they may shut down for a couple of days if things aren't set right. And that's the other thing, is you're going to be constantly tweaking these BMS settings trying to get them to work right. The first few months we had several shutdowns in the dead of summer when we were running multiple air conditioners, and the batteries were getting charged just a little too much, and the BMS got too hot, and then the whole thing just shut down. And the VRM did its job and it sent notifications and everything did what it was supposed to, but it was still very frustrating. So here's my advice to you. Go ahead and just send an email to RECBMS. I should have done this at the very beginning, and I don't know why I didn't, but I just sent them the spec sheets of my batteries and said, hey, something's not right with my my battery charging settings because the BMS is getting too hot trying to balance these cells. And they immediately replied back with the exact settings, and it's been perfect ever since. Also, not having the right BMS settings causes all sorts of other issues. When the system would shut down and reboot, then sometimes the Wi-Fi module or the touch display wouldn't reconnect, and then sometimes it would lose its connection to the internet, and it was just a whole thing. So just get those BMS settings right. Just send them an email. It'll make your life much easier. As of this video, we've had the system running full-time for six months, and we couldn't be happier with the results. It's easy to throw around a bunch of theoretical numbers, but to actually have that real-world experience has been amazing. To see this solar-powered system running silently in the background, especially once we got those BMS settings figured out. Because our house isn't built yet, we're still only using a fraction of this system, but right now our current average is about 13 kilowatt hours of production and about 10 kilowatt hours of consumption. During the summer, when we're running multiple air conditioners, we've seen usage as high as 35 kilowatt hours. I'm excited to see how the system performs once we're actually using it to its full capacity, because right now we're filled back up to 100% by probably 8 or 10 o'clock every single morning. We're just scratching the surface on the amount of solar power output this thing can produce. All in all, this system is a beast, and we know that we paid probably half of what all of our other neighbors paid for their own off-the-shelf systems, and our system is probably two or three times the capacity. Now I'm not saying this to brag, I'm just saying that it's really cool how big of a system you can build at such a small cost if you learn how to piece all these components together yourself. Plus, if you build it right, you can switch out components and grow as needed. It's not all unicorn and rainbows though. Hindsight is always 20-20, and there are a few things that we would do differently, so let's talk about those real quick. Understanding Alibaba's payment and shipping methods. This whole process was very uncomfortable for me. I didn't understand why they wouldn't take my credit card, I didn't understand why after I paid for it they tried to give me a different product, and then I didn't understand why it took so long to ship and why they couldn't give me meaningful updates. It's a very different process from buying something on Amazon, but now that I know how that process goes, I'm okay with it because I saved a ton of money on batteries. But at the time, it was very stressful. Solar panel wattage. Now yes, we got a great deal on our solar panels. We mentioned that we only spent 25 bucks a panel, but here's the thing, that solar ground mount, that massive solar ground mount that we had to build, cost almost five times as much as the panels themselves. So what we would have done differently is we would have spent more money on higher capacity panels that should have been roughly the same size, and then built a solar ground mount that was much smaller, which would have reduced that cost. The only upside is that now we have a huge solar ground mount, and if we want to replace with those higher capacity panels, we can totally switch them out and do that down the road. Smart solar battery voltage. Like I mentioned, I didn't have the right things turned on when I flipped on the solar charge controllers for the first time, and they couldn't read the battery voltage, and caused all sorts of problems. Don't be like me, make sure it can read that battery voltage on startup. BMS balancing settings. And finally, like I said, I really should have just emailed REC a long time ago and gotten those exact BMS settings for my specific battery cells. Would have saved me a lot of stress those first couple of months. Now you may be asking, how much did this all cost? You keep saying it's like super cheap, but you haven't given me any numbers. Well, this thing got so long that we're going to have to do the cost breakdown in a separate article and video, which should be coming soon. But in the meantime, again, that article that we've linked to a few times in this video has links to all the products in it, so you can go ahead and piece that together yourself if you're in a hurry. We'll come back and we'll add a link to that video and article when it's finished, so make sure you're subscribed so you know when we put it out. Hey, congratulations! You made it through our nerdiest video ever. I'm not sure how I keep talking myself into making these really long, detailed, nerdy posts and articles and videos. Well, it's really good information and it's something that we were looking for when we tried to build our system, so you're just helping other people. Yeah, speaking of, we have to take a minute and we have to thank a few other people who came before us because obviously there's a ton of DIY solar information out there on the internet already, and we were inspired by a few important people. One is Michelle and Juan from beginning from this morning, who helped us build our whole system, piece it together, and helped us understand how it all worked together. Not only that, but they built the battery box and, I mean, they did so much to help us. We could not have done it without them. Also, Handyman and Wild Wonderful Off Grid for showing us how to build the frame that our solar panels go on. Yeah, because like we said, that was a whole thing and they had some really great videos that helped explain the best way to do that. And finally, Will Prowse of DIY Solar Systems. He does super deep dives on all sorts of lithium batteries. Really great resource if you're going to go down that road. I hope that this installation breakdown and wiring diagram help you understand how to build your own massive off-grid solar power system in a way that's safe and cost effective and reliable. Now, we are just getting started here on an off-grid homestead. Our house is not built yet, but that does begin this year in 2022, so make sure you're subscribed if you would like to see how all this power will work for our house. Don't forget, we do have that full wiring diagram for download if you want to check that out, and that cost breakdown is coming very soon. So again, we hope this was useful and we'll see you soon.