2000w, 24v solar system

[guidecca]

Hello Folks,

I'm trying to buy parts for and build a 2000w, 24v solar-powered system. I'm a newbie.

On Will Prowse's website here: https://www.mobile-solarpower.com/2000-watt-24v-solar-system.html, under the picture (attached) he states that, "Due to a recent change by Victron, the battery protect is not recommended for this system. Just connect everything to a bus bar or surface mount terminal."

He calls it the battery protect but it does not look like the blue item in his video here:

.
My question is what would picture revised without the blue battery protect look like?

Is this the battery protect mentioned in the video: https://www.amazon.com/gp/product/B079ZL6WPD/ref=ox_sc_act_title_23?smid=A2TN19FHI2Z5KL&th=1

Also, he mentions using 4 gauge wire for battery to inverter. Should I use 4 or 2 gauge? Thank you for any assistance.

 

[snoobler]

You've linked a fuse holder, not the battery protect.

You can always use thicker wire.

 

[guidecca]

Thank you for pointing that out. There was no link to the battery protect on the components list and since it is not needed now, how would the wiring look? Wondering where the wires that went to the battery protect are supposed to go now. At least it got me to wondering whether I'm up to building this thing. I've already ordered four 100 Watt 12 Volt Monocrystalline Solar Panels. Maybe I should buy the book.

 

[snoobler]

In most cases, the battery protect is just omitted. The way it's being used in that video is against the manuf's recommendations. It's not designed for that. It has to do with the surge of the inverter when it's reconnected - it can greatly exceed the rating as the inverter capacitors charge when first connected.

 

[guidecca]

I was hoping to leverage the 24v system for more power. Will made it look easy. I don't know now.

 

[guidecca]

This 2000w, 24v solar powered system is described in diagrams unfamiliar to me. Is there a picture diagram for a four panel system with positive/negative connections that the untrained, inexperienced person can understand and build? I think I understood the 12v DIY systems described in Will's videos. This 24v system is the one I want; how much would it cost to get a picture diagram?

 

[snoobler]

I guess I'm not seeing where the confusion is:

RV Solar Power Blue Prints

Building a vehicle mounted solar power system? Let me help.

www.mobile-solarpower.com

What don't you follow?

 

[Dzl]

So if I understand your question, not using the battery protect in that way would actually simplify things slightly. It would just require you to get a slightly better inverter than the one will reccomends, something with a low voltage disconnect that works for LiFePo4 (if that is the battery type you will use).

The battery protect in that diagram is being used to control DC loads (okay) and Inverter loads (not okay). A decent inverter can control itself and thus sidestep the error in the diagram.

So what you would need to change is only run DC loads through the battery protect, the controller and the inverter should bypass it entirely and be controlled by their own programming.

So you would have:

                              |---> Inverter -----------> AC distribution
[ +Battery ] ---> [ +Busbar ] |---> Charge Controller --> Solar Panels
                              |---> Battery Protect ----> DC distribution

 

[guidecca]

So as I look at this tangle of wires with a caveat that the battery protect is not needed I ask my self what should this picture look like? How is it wired? I can't read even simple diagrams. I can make things work but the symbols I need are the pictures. So, the battery protect stays but only gets DC connections; please pencil in where the wires are supposed to go in the .png file I sent? Where would I look for an inverter? I use the links that Will provided to source the parts. I'm getting ready to pull the trigger on an order to Amazon for the inverter in this picture. Can you recommend another inverter? Thank you. I attached a "better" copy of the picture.

 

[guidecca]

I guess I'm not seeing where the confusion is:

RV Solar Power Blue Prints

Building a vehicle mounted solar power system? Let me help.

www.mobile-solarpower.com

What don't you follow?

Snoobler, I can't read diagrams. I can source the parts with Will's links; I can look closely at how the wiring is set up and that is it. That was enough for the basic 400w, 12v DIY system. The 24v system is not clear to me.

 

[guidecca]

I've indicated that I have no idea what to do with the battery break. I am trying to build a solar system; need the system to social distance in my van. Do not need a DIY self-taught electrical degree and do not desire to stop at every motel between Virginia and Cali. The title of the video was DIY; I assumed it would show anyone how to build it. Thanks for the help. If worse comes to worse I will build the 12 volt system and buy Will's book to see if it helps.

 

[Dzl]

Here is a quick sketch (there are probably omissions and/or mistakes) of my take on the system in the picture, with a couple modifications:



I look at Will's example systems as good basic starting points, I learned a lot from those videos. They show how simple and accessible a basic system can be, and use the minimum amount of components possible in most cases, this is good for learning because it doesn't over-complicate things, but has some limitations. To me, many of the examples are more like quick and dirty starting points to adapt to your needs, than systems to follow to the T. And no matter what, going the DIY route should include some mental legwork and research on your part, its important to understand what you are building at least at a basic conceptual level.

I believe the only changes I've made are adjusting it for the Battery Protect, adding a positive bus bar, adding a battery monitor (which his schematic omits but the text recommends), adding basic default grounding (but follow the recommendations of your inverter manufacturer).

This design requires that you buy an inverter with a proper low voltage disconnect compatible with Lifepo4. I recommend buying through a reputable specialized seller and not amazon/ebay, they know their products better and have better curated selections. Altestore.com and Baymarinesupply.com are two options. Most top tier and many mid tier inverters have adjustable low voltage protection. I would look for an inverter with an LVD at least as high as 22 volts, but ideally LVD should go up to 24v to 25.6 volts. Victron, Samlex, and Xantrex are some options. I'm sure there are others, and probably some more budget oriented options, but I can't reccomend a specific option.

 

[guidecca]

Dzi, thank you! Your advice and the quick sketch are really appreciated. "Probably omissions and/or mistakes" withstanding, it is great progress forward for me. Except for the inverter can most of the original components in the video be used?
~ I am guessing that AC distribution would be important; would we plug devices into the back of the inverter or could the AC go to a breaker box? ~ Would you recommend an inverter or an inverter/charger? I don't recall that there was a way to charge batteries from shore power. Seems like it would be important if you are on the road and are running low. The inverters are cheaper.
~ Would two Battle Born LiFePO4 Deep Cycle, 100Ah 12v with built-in BMS, 3000-5000 Rechareable batteries in series work and could the system still be over-paneled in the future?

 

[Dzl]

Dzi, thank you! Your advice and the quick sketch are really appreciated. "Probably omissions and/or mistakes" withstanding, it is great progress forward for me. Except for the inverter can most of the original components in the video be used?

I think so yes, with the caveats that (1) I ignored the ATS in the diagram, and don't know anything them, and (2) I would buy fuses and breakers from a reputable manufacturer/seller. But otherwise everything looks good.

Epever is a pretty good budget charge controller from everything I've heard, I would consider Victron as an option as well, likewise a Victron inverter/charger would be a top contender for me (along with Samlex)-- a lot more expensive than what you were considering though.

~ I am guessing that AC distribution would be important; would we plug devices into the back of the inverter or could the AC go to a breaker box?

"AC distribution" was left intentionally vague. For a very simple and small setup, AC distribution might just be the built in inverter outlets, alternatively you could hardwire the AC side of things and install outlets, in which case you need a breaker box, the latter is most likely what you will do with an inverter/charger. It is beyond my comfort or level of confidence to comment on specifics on the AC side. But I will say if you want shorepower capabilities look for an inverter/charger that is UL458 certified or compatible. This certification has to do with grounding.

~ Would you recommend an inverter or an inverter/charger? I don't recall that there was a way to charge batteries from shore power. Seems like it would be important if you are on the road and are running low. The inverters are cheaper.

If you want the ability to charge from shorepower or a generator an inverter/charger is very convenient. That is how I would do it.

~ Would two Battle Born LiFePO4 Deep Cycle, 100Ah 12v with built-in BMS, 3000-5000 Rechareable batteries in series work and could the system still be over-paneled in the future?

I don't 100% understand the question here.


^^
This is all just my 2c, I'm not an expert so don't go out and buy everything on my input alone. But I do think for the most part, my suggestions above are inline with many folks on the forum with more depth of knowledge and experience than myself.

 

[guidecca]

I think so yes, with the caveats that (1) I ignored the ATS in the diagram, and don't know anything them, and (2) I would buy fuses and breakers from a reputable manufacturer/seller. But otherwise everything looks good.

Epever is a pretty good budget charge controller from everything I've heard, I would consider Victron as an option as well, likewise a Victron inverter/charger would be a top contender for me (along with Samlex)-- a lot more expensive than what you were considering though.


"AC distribution" was left intentionally vague. For a very simple and small setup, AC distribution might just be the built in inverter outlets, alternatively you could hardwire the AC side of things and install outlets, in which case you need a breaker box, the latter is most likely what you will do with an inverter/charger. It is beyond my comfort or level of confidence to comment on specifics on the AC side. But I will say if you want shorepower capabilities look for an inverter that is UL458 certified or compatible. This certification has to do with grounding.


If you want the ability to charge from shorepower or a generator an inverter/charger is very convenient. That is how I would do it.


I don't 100% understand the question here.


^^
This is all just my 2c, I'm not an expert so don't go out and buy everything on my input alone. But I do think for the most part, my suggestions above are inline with many folks on the forum with more depth of knowledge and experience than

 

[guidecca]

So, I know I should buy an inverter with adjustable low voltage protection, though I have no idea why, does the EVO series have such a model? What are the consequences of going with the pure sine wave inverter in the video. If I break it I am out $200-$300. If I break an EVO I am out $1000 to $1500. Why not stay with the video?

 

[Dzl]

So, I know I should buy an inverter with adjustable low voltage protection, though I have no idea why, does the EVO series have such a model?

Because the ones that aren't adjustable virtually always default to a voltage meant for lead acid which is too low for lifepo4. It doesn't need to be adjustable if you can find one that works for lifepo4. However the adjustability is very nice because you can fine tune your system.

I believe all Evo models have configurable low voltage disconnect, it may require purchasing the remote panel (i'm not sure, but some manufacturers do this--a shitty sales strategy in my eyes but quite common with inverters).

What are the consequences of going with the pure sine wave inverter in the video. If I break it I am out $200-$300. If I break an EVO I am out $1000 to $1500. Why not stay with the video?

Three main differences:
1. Build quality + Grade A support and documentation
2. Configurability + Adjustable Low Voltage Disconnect
3. Real surge rating (this is important for things with motors, tools, A/C, etc).

In terms of a (relatively) cheap inverter, there is nothing wrong with the Giandel in the video other than that it doesn't have a low voltage disconnect compatible with lifepo4. You can use it, but you need a workaround (the original reason Will tried to use the battery protect). I believe some people have wired the switch to a relay, if you used something like a voltage sensitive relay, you could maybe make your own LVD, but this is beyond my level of understanding and those relays ain't cheap.

Alternatively, if you will not keep your inverter on 24/7 and just use it when you are present and switch it off when not in use, you could get away without an LVD though its not recommended. Your BMS would cut power before damage is dont to your batteries so its not like a big risk, just unideal/inconvenient

Beyond the above, the comparison between top tier low frequency inverters and budget options like the Giandel largely comes down to build quality and quality of components, surge rating, specs, and the quality of the companies behind them. But I hear you on price, it doesn't always make sense to shell out more cash for a higher quality product, it definitely depends on your use case and priorities. I would suggest spending some time looking through the inverter subforum on this site, there are a number of really good threads and reccomendations. You may be able to find an inverter that is a compromise between the Giandel and a more expensive inverter in the 500-700 range. Or if you reassess your power needs you could get a very high quality 1200W inverter (bearing in mind that 1200W from a top tier inverter is a lot beefier than when a budget inverter carries the same rating) in the ballpark of 400-650 (Victron Phoenix or Samlex Evo 1200)

Kisae and Xantrex might be companies worth researching as well

 

[guidecca]

Dzi, I pulled the trigger on an inverter charger, Samlex EVO-2224 2200W Pure Sine Inverter/Charger, Samlex EVO-RC Remote Control, and 175A Class T Fuse Kit from Don Rowe. They matched the Anchor Express price for the inverter charger and remote control. The solar panels are coming, the book is coming, and the stuff from Don Rowe will be here next Friday (from Oregon). Not really sure where the 175A fuse kit should go; maybe between the batteries and the inverter. Do you see any alternatives to the Battleborn batteries? Was going to buy two and put them in series to make 24 volts. Thanks for helping with the diagram and advice. This EVO-2224 has adjustable LVD, warning, and reset so it looks to be okay. Opinions?

 

[guidecca]

Change 1, Don Rowe called and said that the Samlex warehouses do not have an EVO-2224. I ordered one from Anchor Express online. If it doesn't work out with Anchor Express, start from where we left off. This pandemic has screwed everything up with shipping.

 

[Dzl]

Dzi, I pulled the trigger on an inverter charger, Samlex EVO-2224 2200W Pure Sine Inverter/Charger, Samlex EVO-RC Remote Control, and 175A Class T Fuse Kit from Don Rowe. They matched the Anchor Express price for the inverter charger and remote control. The solar panels are coming, the book is coming, and the stuff from Don Rowe will be here next Friday (from Oregon).

awesome!

Not really sure where the 175A fuse kit should go; maybe between the batteries and the inverter.

I would locate this as close to the battery as possible if this is to be your main battery fuse. All current flowing in/out of the battery should flow through it. I would personally size the wire to handle at least ~220A, which I think might translate roughly to > 1/0 AWG but I encourage you to reference a wire size calculator or ampacity chart (screenshots in my profile) and adjust to your conditions (important variables include insulation temperature of the wire, ambient temperature, whether the wire is bundled or in conduit, and wire length). If all that sounds too complicated, err on the safe side, just choose 105*C rated marine wire of 1/0 or larger and keep your wire run short and you will be good to go.

Do you see any alternatives to the Battleborn batteries? Was going to buy two and put them in series to make 24 volts.

Lots of alternatives, just depends what you are looking for. Battleborn are expensive but they are a good product from a good reputable company with a good warranty. If I was going to buy drop-in lithium batteries I would strongly consider Battleborn, especially if I wanted something consumer friendly with a minimal learning curve.

The cheapest option is to build your own using raw cells from aliexpress or alibaba ('grey market cells') there is a much steeper learning curve and more risk and responsibility with this route, but considerable cost savings per kWh.

Middle ground options include:

• sourcing used Valence batteries (drop-in replacements),
• buying a cheaper drop-in replacement alternative to battleborn, I don't have a brand to recommend but there are many options including the costco deal. Personally I would be semi wary of a company you may come across called SOK, I have no reason to believe they sell a bad product in fact they might sell a very solid product, but they are a very new company and there appears to be a lot of astroturfing / manufacturing of interest going on with them right now.
• buying higher quality grade A (non-grey market) raw cells from the manufacturer or a distributor and building your own battery (same responsibility and learning curve as the grey market option, but more uniformerly high quality and less risk--though still some).

In your case, I think it may be a good decision to stick with BattleBorn or a similar option (maybe the Costco deal) unless you want to take on an additional DIY project / learning adventure in which case the raw cell route is an option. I encourage you to do your own research.

Thanks for helping with the diagram and advice. This EVO-2224 has adjustable LVD, warning, and reset so it looks to be okay. Opinions?

From everything I've read the Samlex Evo is an exceptional inverter that should serve you well for years, the manual is great (I reference it all the time and I don't even have a Samlex Inverter) and tech support is supposedly very helpful and knowledgeable. I think you made a good choice.

The Evo also gives you the option to pass the Solar Charge Controller through which opens up some additional functionality that may or may not be useful for you. And the second AC input for a generator is very useful in some use cases.