Essentially, pic-related is everything I need to know, but I'd like to talk about it anyways.
How can I keep it legal? (I'm in Germoney, so I can only do a "Balkonkraftwerk" without involving the power company, meaning I can at max have 800W flowing into the grid. Of course, I'd rather not have anything flowing into the grid, using it all myself, so that means batteries, but that is either expensive, or I'm not sure if my electrians-skills are good enough for that.
tl;dr:
What do you have on your roof and how did you put it up there?

>>2903345 (OP)
>I'd rather not have anything flowing into the grid
That's not always desirable since, solar panels being cheap, you'd usually want to oversize the system - provided you're not limited on space. Conversely batteries being somewhat expensive, you usually wouldn't want to buy a battery big enough to store enormous amounts of excess.
I saw someone posting a $1k-ish literal balcony setup sold in Germany with a "solar generator" managing everything, and for that price, and being plug&play, it was a decent deal.
Total /diy/ of a battery is not hard at all, but it is very dangerous to fuck up. In current year and current market, buying a complete battery parts kit with everything except cells, including a JK-BMS, and then plopping in 280-300Ah A-grade cells from nkon would be the way to go.
>What do you have on your roof and how did you put it up there?
~5kWp in 410Wp cells all roof mounted, had a company do a complete install. Will be semi/diy/ expanding by another 8kWp this year on another roof, plus in a different location doing a full /diy/ install for a ~4kWp initial set, possibly ground mount, and another 4kWp roof mount later.

>>2903345 (OP)
>What do you have on your roof and how did you put it up there?
Some panels, screws

>>2903345 (OP)
what do you guys recommend to affixing solar panels to the ground? currently i am in the process of buying a terrain next to mine and i need to put temporarily the panels in the fence between our terrains, upper side in the fence, the other in the ground. I dont want to do anything permanent, as i hope it wont be there for more than a year.
would camping stakes be a good idea?

>>2903700
I haven't used ground screws, but they seem fairly easy to install and remove. Alternatively find some bricks or concrete blocks and do weighed panels.

>>2903345 (OP)
>What do you have on your roof and how did you put it up there?

Am i doing it right?

Only two on the actual roof, however a quick count has 50 of various sizes attached to the building.

>Idiot has those two on the side

The two 100w panels on the side are to boost the system in the winter, on clear days they put out around 50% more than the two identical ones on the pivoting mount when it is pointed perfectly at the sun. Reflected light from the snow makes them better than ones that are angled 'right'

>>2903711
Same guy. Full baka off grid lit up like Christmas tips:

>Whenever possible use independent systems for the lights, solar barn/security lights ect
>Get cheap solar yard lights from end of season sales at dollar stores or yard sales, like $0.50-0.25 each
>But those suck and the ones from yard sales all have dead batteries!
>Which is why you replace the Ni-Cds with bulk Amazon Lithiums
>Yard sale barn/security light doesn't work because of dead battery?
>Buy all the 'dead' power tools at the yard sale or scrounge 'dead' tool batteries from people you know, at least half of them have perfectly fine 18650s in them the charging circuit board is fried

>>2903569
It was absolutely pissing it down all day and got a pretty poor result out of it.
The bank was also precharged to ~90% but this didn't fill it so I'm not sure what is going on there

Also I wanted to know if anyone has experience with copper tube bus bars?
For the charger wiring I just shoved 2AWG wire in the open tube and smashed the thing with plyers to crimp it.
Should I solder it? I have strong concern that it is not a good enough connection for 100 amps.

I am also aware that running this many batteries in parallel is dangerous, I don't give a shit.

>>2903711
I'd almost guess it's Wayne's, except the house itself looks too decent for that.
>>2903796
All of these connections have to be crimped properly, buy a hydraulic crimper off chinks. I don't think paralleling the batteries is bad if they're lithium, maybe more so if they're not. You should definitely unfuck the connectors and definitely cover up at least one of the bus bars, so that the first wrench you drop on it doesn't immediately do a dead short on a 1000Ah battery.

>>2903345 (OP)
The solar batteries are easy man. I'm retarded and built my own 280ah, you can easily do it.

>>2903812
I think the perceived danger is that the string is capable of 2500 amps in a dead short, so people say to limit it to four at most because the current is less.
Meh a hydraulic or more likely a hammer punch crimp is designed for a proper connector and not a piece of water pipe, I don't think it will work.
I could I guess put proper termination lugs on it and bolt it down to one of the batteries on top of the bus. Kinda starting to have concerns about distribution though, but I should be safe because the max amps is equal to the max control of any one battery so safety wise it's ok

>>2903711
>Reflected light from the snow makes them better than ones that are angled 'right'
sounds like a use case for bifacial panels

>>2903873
A 48V big guy battery can do 20kA+ in a dead short so 2.5kA isn't so bad. The hydraulic crimper could cold weld the pipe just fine, provided you choose the right size terminal for the cross section. You should have a high breaking current fuse on the battery side of the wiring, at least on positive, and then have the thing enclosed. Each battery can give out 100A, totaling at 1000A, while your wiring is sized to 100A. The copper pipe and everything leading to the fuse should ideally be sized to handle 1000A peaks for a few seconds, until the 100A fuse gives. Either way the worst part by far is that the bars are in open air with nothing covering them.

>>2903881
It really is, if i put any on that metal roof i'm absolutely using them.

>>2903890
Ehh I bought all of the batteries because I was going to put them in series and make 120v dc.
I bought a special charge controller and everything for it. But then I realized that if one of the bms ever opens up from temperature, low voltage, high voltage, ect, it would instantly kill itself big time and maybe go on fire.
I tried ordering a 40s bms and the transaction went pretty bad and I refunded it. Now I'm stuck not sure what to do at this point so I just made it 12v for now.


The 120v battery voltage is cool because I found a lot of my electronics just plug in and work fine on DC. I even modified my oven to work on either. But no proper bms is super sketch

>>2904038
i think some bms could be put in series, but dont take my word on it
desu i dont know why systems that can be directly inverted to mains are not more common, it lowers the complexity a ton, needs way less copper.
it is not that unsafe

>>2904064
400-600V batteries exist, which are more closely aligned to solar string voltage. Only that they cost a fuckton. But "it's not that unsafe" doesn't cut it with electrical code.

>>2904067
its more you need an actual electrician to sign for it, not that it cannot be used by code
which i get, but its bullshit that only because of that companies barely do equipment for it
every fucking mains installation need the electricians signature already, why industry act like this is a big deal

>>2904064
>>2904038
>>2904069
Any reason you can't wire two BMS next to each other? If the parameters are the same they should just ignore each other unless one fails.

>>2904112
that is what i said, and there is bms for huge series batteries, seems like regular bms acting as slaves of a master controller, but they are kinda expensive

>>2904112
>Any reason you can't wire two BMS next to each other
Yes, there is a reason.
Bms use a mosfet or multiple mosfets to disconnect the cells from the terminals in order to protect the battery.
The mosfet is a piece of silicon, it has a maximum voltage limit of 60v or something.
If you have a 128v nominal string of batteries, and any load at all, if any bms opens, there will be 128v between the mosfet now and it will rapidly start emitting fire and burn down your fucking house is what I was told.

I was going to get around this by bypassing the mosfet and instead using the mosfet output to keep a giant contacter closed but meh I want something not quite so jank and I'd still need to balance everything

>>2904136
you are getting it wrong, you need to split the bank
example you put a 60v bms in a 60v section of the bank, which is in series with another section like that to get the 120v

>>2904138
Read what I posted

>>2904160
you need to check how bms work dude

>>2904136
>>2904138
>>2904127
Use a controller and a really big active pizeo switch as the BMS. If something fails it will automatically disconnect.

>>2904178
Oh you're right, that's so cool, I hope one day you give it a try

thanks for asking! nothings up there yet but I scored a bunch of free old modules and similarly decrepit microinverters yesterday. which is great and i cant wait to carry them onto my roof but now i need racking and permits and shit so hopefully i actually do it before winter... whole system is maybe 4kw at best but how can i say no to such a passive economic buff?
does anyone know of any charge controllers that work with higher voltages? everything seems to be 12/24V. I have big panels with diodes so is it retarded to think i can attach news leads near the diode for half the voltage and then terminate it in parallel?

>>2904439
Most big panels that have diodes can be setup to half the voltage yeah, you actually just install two jumpers usually.
What are the permits for? I guess if you grid tie but I can't think of a single thing more cuckold than giving away your power for nearly 0 dollars

>>2904459
really was keen on doing non permitted work but i'm already grid tied and cucked as fuck so we're more interested in KWh credits than outright selling. seems most utilities are moving towards time of use billing as a counter to residential solar anyway. ill see if i can get a manageable voltage out of one of these modules for some off grid larp tho.

>>2904525
Actually could not be me ever. Fuck grid so much. My house is solar only, no grid or poles or anything, fuuuuck that shit.

>>2904439
>everything seems to be 12/24V
Where are you looking? I'm more surprised you can find a 4kW charge controller that only takes 24V DC from the panels. Even 24VDC battery is relatively rare, let alone panels. Also why are you talking about charge controllers if you want to be on-grid? On-grid takes an on-grid inverter, no charge controller, no battery. You should probably keep rereading the rentry until you understand terminology and basic components.

>>2904551
Pwm controllers will pull the panel down to battery voltage, so if he's trying to use one (literally why) then it will be doing that and so you want to optimize the panel voltage a little for it

>>2904528
you must be smart to have achieved such status and maintain it. maybe if i had made different choices id be living in a solar powered van by the river. actually dont think i need permits at least because it depends on the cost of the work in my state. not sure how that works with getting permission to operate tho so maybe i will just export to grid and see what happens.
>>2904551
sorry i confused you, the 4KWDC system with the micro inverters i mentioned is grid interactive so it wont work when the power goes down. I also have other different separate panels with Voc's ranging 36-56 VDC. most of the charge controller i see on amazon, ebay, alibaba take 12 or 24VDC input, so i think maybe i can figure something out by asking retards retarded questions on an autistic honeypot weaving forum.
>>2904611
>literally why
fuck around to find out? if one works, than more than one might work better or maybe i dont need any. so i could gain the experience and decide whether to scale up or abandon the project without investing too much.

>>2904692
Those cheapo charge controllers take 12V or 24V battery input, the solar input is usually 25 and 45V, respectively. This isn't even "read the rentry", this is "read the specs".

>>2904692
>most of the charge controller i see on amazon, ebay, alibaba
You have to go absolutely out of your way to get a charge controller that ISN'T mppt now. What are you doing differently?

>>2904883
unless it changed recently the low end of mppt controlers are not actually mppts... and you find them in hardware stores

>>2904889
Idk about that, I got this cheep chinesium one and it is definitely mppt and tanks my 185v VOC. https://www.amazon.com/gp/aw/d/B0DHZN8Q82

>>2904927
that is not low end
i mean the 10/20/30a 12/24v that you see for really cheap

>>2904930
You're in the wrong hobby

>>2905035
i dont use those,just say that they exist,
i got a victron one for the price of a chink one

>>2905039
Victron is chink

>>2905040
not their prices or support

>>2904693
>read spec
reading is hard and i didn't realize the pv input range for the low end controller was that wide. plus high power low voltage seemed weird.. does that mean if you want 2400W from your 100W panels and input is 25VDC your going to terminate 24 modules in parallel on a DC bus?

>>2905127
No they are talking about these blue dogshit pieces of dick ejaculate that are only good for like 150w max.
Like if you use this shit you're retarded, I fucking hate retards that get a bunch of fucking trash and try to use it for some retarded shit.
If you want to put a 20-50w panel to use, find the mppt usb charge controller. It's a tiny black thing with two USB A, one Usb-c and one barrel, no battery just makes usb power. Pair it with a usb power bank and try to sell them to poor people at your church

>>2905127
>input range for the low end controller was that wide
You can always easily drop voltage if you have to, in fact, voltage even drops itself.
>if you want 2400W from your 100W panels and input is 25VDC your going to terminate 24 modules in parallel on a DC bus
Well if you're an idiot, then yes. Note that this is very likely to go up in flames even if you somehow don't fuck the wiring as such.
If you're not an idiot, you'd put them in a string and get a 200-300V charge controller for a few more bucks than the ultra-dogshit >>2905133 controllers. Notably, your controller has to be rated for EVERYTHING you need, that means, voltage, amps and total power, and only then is it reasonably safe to use and capable of performing well. Theoretically you can connect any wattage and amperage to a given controller since the controller will self-manage the amps and drop it to a level it can handle when it's overloaded, but this will only work reasonably on decent controllers, not the $20 chinkshit.

>>2903345 (OP)
I'm building an off-grid. I already bought almost everything I need: panels, inverter and battery. I'm only missing the support structure (which is already on its way).
some electrician is charging me $600 . I'm not rich, not american. should I build the system myself or should I pay him?

>>2905290
Depending on the scope of the system, $600 isn't that bad. It's definitely viable to /diy/, but if you are a total amateur that has never done any electrical, it's possibly not the best place to start. You also might need $200 worth of tools to get started, notably maybe two hand crimping tools and a hydraulic crimper.

>>2905292
>if you are a total amateur that has never done any electrical, it's possibly not the best place to start.
I've done electrical stuff and know a bit of the basics (in fact, I designed the system myself... though I don't remember much about the theory itself beyond power, voltage, current and ohms law. I just go by voltage/power specs, series and watched videos on yt on how to calculate stuff). but I'll be paying this guy just to make sure I don't die in the process of installing this crap. but $600 is kind of a lot considering I've done most of the design and bought most of the stuff I needed by myself... isn't it?

>You also might need $200 worth of tools to get started, notably maybe two hand crimping
I already bought a cheap crimping tool. no idea how good or bad it is, though. I have no clue how these big cables are

>>2905294
How did you design the system if you have no idea how big the cables are?
>$600 is kind of a lot
Again, depends on size and complexity. If it's a tiny solar generator-tier system where you're just gonna plug in 6 cables and call it a day, then yeah.
At the same time, I paid $600 for some faggot to come and hang my inverter on the wall and connect half the cables I paid for him to connect and give me a stamp that a certified faggot electrician did the wiring, so that insurance doesn't whoop my ass if they find out the solar fire was on a /diy/ system. Which still doesn't entirely protect me, because I'd need a project revision for another $600-$1000 to fully legalize it.

>>2905294
>>2905301
*ḧow big the cables are crimped
lmao

>Again, depends on size and complexity
3kW panels (6x550W)
5.5kWh battery
6kW inverter

>>2905310
That's not a small system so if he's gonna do all the work hooking it up to the house, grounding, lightning protection, it shouldn't be a terrible price.
But if it's being built to portable standards with no lightning protection or grounding, and it's just literally plugging the panels into the inverter and the inverter into the battery and a single socket on a single breaker into the inverter, then maybe you're better off /diy/ing.

>>2905311
right. yeah, he's doing all of the other stuff too, but that's not really that expensive. but still, at least I might not be electrocuted or some shit.

>>2905290
What are the panels going on
What is your battery solution
What is your charge controller
What is your inveryer
Do you plan on any DC loads
What are your intentions with the ac, are you trying to tie it into your house or something?
How many panels do you have
Are all the panels the same model/size/specs
What is your target VOC and what is your charge controller max VOC and what is your battery voltage

>>2905643
panels are 6x550W (I really should have bought twice that...), same brand and model, will be mounted on a fixed position on a (adjustable vertical angle) aluminium structure, which will be put on top of a maritime container
inverter/charger/controller is a growatt spf 6000 es plus, and battery is of the same brand.
no DC loads
it's for my house, yes
VOC is whatever the 6 panels give me. it's a little less than 50V for each so 300V
battery voltage is 51.2V

>>2905733
Oh well why didn't you say container in the first place lol. You should easily be able to set this all up yourself.
Everything looks more then great for it too.
It only gets hard when you try to mount stuff to houses and shit.
If you don't have one get a panel disconnect breaker, wire the controller and the breaker first, then after that is all sorted, make sure breaker is off and go plug in the panels up top. The only kill you part is the PV voltage

>>2905737
>Everything looks more then great for it too.
I thought and designed all of it by myself :)

got my eye on a Litime 3500W all in one. how do they rank?

>>2903812
> I'd almost guess it's Wayne's
I miss Wayne. That fucker is entertaining.

>>2906667
It's very budget-tier, probably wouldn't leave it completely unattended. Functions are good for a simple system.

>>2903345 (OP)
You can start with a small battery just to help the panels under heavy load like a capacitor and use the grid at night.

>>2905733
>550w
Those are huge and heavy, it is a two person job installing them.

>>2906964
they are heavy and big, but 28kg and 2m x 1m isn't really THAT much

>>2906853
seems everything is budget tier up until powerwalls. how would you feel about a new litime vs a refurbd growatt?or should i only buy the good blue brand?

>>2903796
There’s calculators online for max amp copper conduction. Usually it’s just a concern of how hot they will get over a certain amount of time. The hotter the conductor gets the worse it is the colder the better (this is how super conductors work.)

>>2908106
GoodWe, Sungrow, EG4 and SolArk. SolArk in particular has fancy all-in-one hybrid inverters. Deye is also good if you can get one for a normal price.
Litime is literally repackaging $250 Aliexpress inverters, though EG4 is also doing some of that. They're not necessarily bad inverters, but at least EG4 probably does some extra quality control.
Growatt doesn't have very good rep on reliability, though they offer good warranty coverage and they are a fairly large company that probably won't disappear overnight, which I wouldn't necessarily say about Litime's US branch. So between those two, I'd go with Growatt refurb, but try to find an EG4 or a SolArk.

>>2908156
This is why all in one's are fucking bullshit.
You have people that make good charge controllers
And you have people that make good inverters.
They don't overlap much but when they do it's haha fuck you pay 3x for your lazyness.

If you are trying to save money but don't want to worry about a housefire or whatever, the answer is not chinkshit or oh which chinkshit will outlast the other chinkshit. Just get used name brand quality chinkshit.
My cotek and my eaton ferrups inverters will outlast the sun itself and I didn't pay jack shit for them.

>>2908119
>The hotter the conductor gets the worse it is
You don’t want to exceed the insulation’s temperature rating.

Can someone explain why you can't add shittons of panels to a small inverter to get as much power as possible even during cloudy weather, and then have an automatically adjusting resistor to keep the inverter from getting too much power during bright days? You'd think getting rid of excess energy would be the simplest possible thing to do, but everyone seems to treat it as impossible.

The peak of this was a discussion with a solar system seller, who only admitted that any kind of adjustment at all was possible when I had argued it down to an automatic curtain that physically blocks part of the panels when the current is getting too high. At least that would work apparently, but why on earth we can't simply add a resistor to the wire?

>>2909753
>Can someone explain why you can't add shittons of panels to a small inverter to get as much power as possible even during cloudy weather, and then have an automatically adjusting resistor to keep the inverter from getting too much power during bright days?
Because the inverter already does this on its own. There's no "excess energy", there is as much energy as the inverter pulls from the available pool. On top of that, every inverter will downregulate itself if it comes near to overheating. As to why people don't put up a shitton of panels, it's because
a) companies will rape you on the price
b) it takes up a lot of space
>with a solar system seller
Solar system sellers have NO IDEA AT ALL about solar systems. NONE. They know NOTHING. Do not ever expect them to answer any technical question whatsoever, other than lying about the ROI.

>>2909754
>Because the inverter already does this on its own. There's no "excess energy", there is as much energy as the inverter pulls from the available pool. On top of that, every inverter will downregulate itself if it comes near to overheating.
From what I've heard, getting too much power from the panels breaks the inverter, and the 10KW inverter I ended up getting is exceptional in that it can scale 13KW from panels down to what it can handle.
>Solar system sellers have NO IDEA AT ALL about solar systems. NONE. They know NOTHING. Do not ever expect them to answer any technical question whatsoever, other than lying about the ROI.
This I can 100% agree with. They seem obsessed with annual production - which tells nothing about how much the inverter produces in spring and autumn, aka. when most electricity is needed. I ended up having my system designed by a friend, but he too just shook his head at the resistor question and said that a resistor of that size would have an insane form factor. Considering electric saunas heat with 10-20KW, a device the size of a stove outside the house doesn't sound big at all.

>>2909766
>From what I've heard
You've heard wrong then. Too much voltage breaks the inverter, someone might've conflated voltage and power along the line. In terms of amps, you can connect any amount you want, because the inverter dictates how many amps it draws, therefore the inverter also dictates the power it draws. If this wasn't true, they'd have no way to manage overheating other than shutting down entirely, but being able to manage amps is a direct consequence of how they're designed regardless of overheat management. You can connect 50kW in panels to a 1kW modern inverter as long as you match the voltage. Conversely you can't even connect 1kW to a 50kW inverter if you overvolt it. Your friend also doesn't understand solar inverters if his answer was different from mine.
Now there's something to be said about general safety that maybe you shouldn't massively (meaning like, order of magnitude) oversize your solar array, and (more importantly) that it's usually not efficient to put many panels on a single string/single MPPT, but it's not a technical limitation. Any modern inverter can handle any size solar array, provided you match voltage (and you don't exceed the cable amp rating, another safety limitation rather than a technical one).
Again, forget about the resistor, EVERY modern inverter can INHERENTLY do what you want. It makes complete sense to do what you want, and every MPPT inverter can do it already without any modification whatsoever. Read the rentry, then read inverter manuals (ideally hybrids, since their modes of operation really highlight this capability), sooner or later you'll understand volts and amps and MPPT.
But if you insisted on being retarded, then the resistor you're looking for is called a solar dump load. People use excess solar power to heat domestic hot water and such. The economy behind it is bad, in other words, it's usually not worth the investment, but it does exist.

>>2909766
>From what I've heard, getting too much power from the panels breaks the inverter, and the 10KW inverter I ended up getting is exceptional in that it can scale 13KW from panels down to what it can handle.

The other guy is mostly right, but the long answer is that it depends on implementation details.

Fundamentally, the circuit that converts power from the panels into something the battery system or local power grid can use is going to be a variant of one of the most basic types of switch-mode power supply. Ideally, it should be able to cope with any amount of available solar power as long as it's within an allowable voltage range.

However, complications show up primarily in the form of how MPPT (maximum power point tracking) is implemented. Solar panels (most things that generate electricity, really) produce maximum power at a specific level of voltage and current output, which varies mostly depending on how much sun is hitting it, and a little on the temperature of the panel. Ideally, a good controller will be able to seek out and find this point of maximum power and either deliver everything the panels can produce to the batteries/grid, or limit it to whatever the demand currently is. If the array can produce more power than the charge controller/inverter itself can handle, it should, again, not have any trouble limiting its own output so as to not cause any damage.

The actual problems arise in cheap, badly-designed power supplies that don't do this correctly, or, worse, expect a specific system capacity and don't do it at all. The bottom-of-the-barrel PWM based charge controllers are likely the most common offenders here. There SHOULD be no problem with having effectively unlimited current available from the panels. Consider that every single power supply in your house has no trouble with being plugged into mains power, even if they only deliver a fraction of a watt.

>>2909776
>The bottom-of-the-barrel PWM based charge controllers
Yeah, I considered that outside the scope here since anon was talking about ~10kW systems. You shouldn't even connect half of the amps of what the aliexpress $20 controllers are rated for, they burn up. But large inverters that are sold domestically, either EU or US, have to comply with standards that more or less dictate that they have to handle overcurrent without dying.

>>2909753
>>2909766
>add a resistor

Doesn't really work that way. All this would do, from the perspective of the power supply, is increase the impedance of the voltage source it's getting its power from. It's not necessary, and outright detrimental during normal operation, as it just wastes energy.

Again, the charge controller/inverter itself should be monitoring input/output current and adjusting itself as necessary. That's a fundamental, basic function of any power supply that implements any sort of current limiting. 98% of solar equipment does this just fine, and it doesn't need any consideration beyond ensuring basic electrical safeguards (proper isolation and fuses, mostly) and ensuring the voltage of the PV array is within the equipment's rating.

If I'm connecting 48v batteries in parallel, is there a special kind of fuse that is needed? I heard that extinguishing a 48v DC arc involving many hundreds of thousands of amps (in case of a dead short) is very hard and your fuse might just arc over and burn everything down even if the actual metal wire in the fuse blows.

>>2909834
>hundreds of thousands of amps
I meant hundreds OR thousands. I'm not dealing with a room-sized battery here lol.

>>2909834

Depends on how large the battery bank is. The three important ratings on a fuse are:

1.) Trip rating
Simply the current the fuse is expected to blow at.

2.) Maximum voltage
Self-explanatory.

3.) Interrupt rating
The maximum current the fuse can reliably be expected to handle when it trips. This rating needs to be at least as high as the power source being fused can put out in a short-circuit condition. In this case, the maximum current your batteries will supply if they're shorted out.

If this is like an ebike battery, you're fine with relatively typical fuses. Unless you have some extremely high-performance cells, small packs like this can't manage more than a few hundred amps in a dead short. You still shouldn't be using automotive blade fuses, even though there are plenty of random Chinese fuse holders made for exactly this purpose, though.

If this is more like a solar/EV battery, where we're talking tens of kWh or more, you need a more serious fuse. Look up solar PV fuses. They typically start out at 10kA-20kA at 1000V. You can figure out what fuse class (type) you're looking for on your own, if you look up the specs, but it's a bit of a pain. Those made and sold specifically for solar installations are already in the sort of voltage/current ranges you'd be using with large-ish batteries.

>>2909834
https://rentry.co/solarshit#fuses

>>2903345 (OP)
So what happens in 10-15 years when the panels start to degrade all of a sudden?

>>2909947
It's not sudden, it's constant 0.5% yearly degradation. You either just accept that you have ~7% less total power, or add one or two panels to the string.

we have:
2440w PV
12K hybrid controller
300AH FLA @ 48v

it is sufficient to power our home entirely during solar hours. we generally draw between 450w to 1200w throughout the day. even though we only have 2440W PV, it is able to pull from batteries if we exceed PV production.

our system is grid-tied, but DOES NOT EXPORT to the grid. this allows us to import power during PV shortfalls or overnight, so we do not cycle our batteries, leaving them charged and ready for a grid outage.

ROI estimated at 13-15 years, at current investment & current capacity. it is NOT about "free electricity" or "getting my money back" it is about having resources when others don't. in the 8 months since install at the new farmhouse, we have had 3 power outages that would have resulted in food loss, not to mention simple inconvenience. we're talking about 2x 4.5 cubic meters of frozen farm & game meat, not to mention the kitchen freezer/refrigerator.

we built this house for maximum power efficiency, having already owned and operated the solar power system at our old, suburban house. Mini-splits, heat pump water heater, grundfos10 well pump, all LED, wood heat & cooking backups, propane main kitchen oven/range. spray foam insulation, zip board & tape construction.

on top of all that, we are just observant of our power consumption.

next upgrade will be a 300AH LiFePO4 trophy battery. eventually, after that, we will focus on PV upgrade/expansion. we have dual MPPT input, so we can run two independent, dissimilar arrays, while still getting full functionality on both.

All DIY installed. every panel, battery, rail & screw. shiiiiiiit.... we even built the shed it's mounted on/in.

picrel was an irrigation day - multiple orchards ans gardens.

>>2910047
Should probably get more panels before any other investment, you're pulling ~70% from grid on a fully sunny day. Maybe /diy/ the LFP battery to save money there.

>>2910047
same as anon, get more panels if possible

>>2903345 (OP)
Must it be on the roof where it will forever interfere with roof repairs? Freestanding atop a frame could add shade like a gazebo and make inspection, cleaning and maintenance easy.

>>2910086
There's nothing wrong with freestanding, if anything it's better to do freestanding if you have plenty of space. But panels need extremely little cleaning and maintenance, the only advantage as such is that you can clean off snow if you have to/want to. Only potential issue can be permits, some places require more legalese garbage for freestanding than building integrated.

>>2910050
>>2910084

thr high usage is due to irrigation. that's why I mentioned it in the picrel description. when not running irrigation or clothing dryer (new LG heat-pump purchase replacement planned July) our system makes several times over our use. on the rare occasion that we had to rund down our batteries, it was able to recharge them while powering our house, with no grid-assist, in about 5 hours.

math was in the post. we average 400w-1500w, generally more around 700w. PV can produce 2440w at peak. usually carrying us 100% by 10:00.

I'd love to have more panels, but money matters. LiFePO4 can charge 4x faster than FLA, leaving even more PV available for daily use. we will feel more real-world benifit from battery upgrade first.

here's today. giant spikes (7k) is our electric clothing dryer.

>>2910092
That's cool and all but what if it's not totally sunny? Your daily consumption seems to be around 12-15kWh, 2.5kWp will not cover that on most days of the year, not even on average, not even accounting for conversion losses, not even if you live near the equator. But if you live near the equator, then at least you won't be far off.
>LiFePO4 can charge 4x faster than FLA
You can charge the 15kWh FLA array full blast here, 2.4kW would be only 0.15C. LFP can charge up to 1C, but probably best to keep it around 0.5C.
Regardless, switching to LFP is good, but with mere 2.4kW in panels, the only immediate benefit will be increased capacity from better DoD. I'm guessing you're not using the FLA batteries in hybrid mode because you try to keep the ~8kWh as reserve for UPS.

>>2910097

2.4kw panels is not enough. but they are paid for. the entire system is paid for. in a world where money was not a constraint, I would have more panels AND more batteries. seeing though, how that is not the case, I have to choose & allocate available financial resources for best overall results. based on my experience, in this house, with this system, at this latitude, I believe my best & first expansion should be into LiFePO4 batteries.

it would be nice to go totally off-grid. that is the eventual target. until then, it lowers our monthly bill & is able to cover 100% of all *critical* loads, during non-solar hours. in a crisis, that really just means our 2 chest freezers and 2 upright fridge/freezers, only one of which matters; the kitchen fridge. other than that, the only critical necessity is our well pump. it's a grundfos10, so it is also quite efficient.

>>2910091
well panels are teh cheapest, but if you are limited somehow, well you need to adjust

I just bought a home and the seller didn't know how old the roof is. It could be 5 years old, could be 15 years old. Should I just wait until I need a new roof before I even consider having solar panels installed?

>>2910213
could you just check?
or are your roof one of those shits that only last 10 years? why you people do that?
where i am from we only use roof tiles or slate, they last forever
in any case, panels should give extra protection to the roof

>>2910213
Get someone to check the roof for you? Depending on roof type, adding/removing solar is not such a big deal. If you can save $1k a year with solar, then it's probably worth to pay some guy to remove the panels and reinstall them after 5 years than waiting 5 years for a new roof and installing it after. Alternatively, do a ground mount if you have the space, or a solar pergola.

Are there any aliexpress inverters that have a good (single digit watts) standby power consumption? None of the listings I found talk about standby consumption, which makes me think it's quite high. I want an inverter that I can just leave on all the time without it chewing up my battery. Or should I just go with name brand expensive ones?

Are batteries really still the best home-scale energy storage solution? Especially for shit like long-term storage (think summer banking up for winter), it's bewildering that there seems to be nothing better. Is pumped water storage really that shit? What about water electrolysis to store pressurised hydrogen?

Even something with mediocre efficiency, on the order of like 20-30%, would probably still be massive if your offgrid setup could utilise its summer overhead to handle winter draughts, just because of how much wasted capacity you otherwise have. And for permanent setups you could easily have something requiring a bit of tooling or infrastructure. Yet the best thing that seems to exist is just the same tech you put in your wristwatch and alarm clock but stacked 1000x to make it bigger.

>>2910447
>Are there any aliexpress inverters that have a good (single digit watts) standby power consumption?
That depends on what performance range you're looking for, but I don't think such a thing exists with inverters that offer rapid- or live UPS. Even Victron uses around 20-25W standby (plus another 10-15W for other victron meme shit that you'll probably have connected). I have a 2.4kW 24V chink unit and it has I think about 20-30W standby, which isn't bad for chinkshit. 12kW 3-phase Deye has 80W standby.
>I want an inverter that I can just leave on all the time without it chewing up my battery
The solution is getting a big enough battery and solar system that it doesn't matter.

>>2910498
no, the best shit is just spaming more solar panels, and insulating the house
if you are in a windy place, and you want to expend the money, you could get an wind generator, but those are not cheap. the 300 bucks one are shit
realistically, just have a gas generator to get an extra power one or twice a year, it also serves you as a backup, and to use in the countryside or whatever

>>2910501
Wind power could be cool if you could viably have floating generators. The colder months are pretty windy here and much windier the higher you go, but probably not windy enough for ground-based generators.
In my personal case more solar panels is limited by roof space, I live in european suburbia so I don't have that much land to just plop down a large solar farm. And yes that does mean that I don't actually need to be off-grid - I probably could with enough effort but it's just not economical, and that's really what I'm complaining about here. I'm basically just yelling at the universe that scaling up multiple orders of magnitude from the tiny lithium cell in my phone doesn't make anything more interesting viable, you're just stuck using larger lithium cells and that's it.

>>2910498
>Are batteries really still the best home-scale energy storage solution?
Yeah, especially with how cheap they are getting, you have no chance of achieving better price/performance with anything else.
>Is pumped water storage really that shit?
For long-term storage? It's worse than shit, you'd need to dig out a massive lake on top of a large hill and then another massive lake on the bottom. If you don't have a large hill on your large property, rip in pepperoni.
>What about water electrolysis to store pressurized hydrogen?
You're gonna spend huge amounts of money to get a 30% efficient system, which would still be huge, because hydrogen has low density. This is a multi-million dollar investment for powering a regular house
>best thing
Exactly as >>2910501 says, you spam solar panels and get a reasonably large battery, then you produce enough in the winter to cover your needs. Solar panels are like <$200/kWp including mounting and wiring, you put up 30kWp for $6k, get 30-50kWh in LFP batteries for another 5k, put in a generator for the couple weeks with absolute dogshit sun, ???, you have a good off-grid system for $15k.
>>2910504
>you're just stuck using larger lithium cells and that's it
I'd argue it's pretty cool that you can use a couple bricks of LFP to store as much energy as a water tower worth of hydro storage.

>>2910504
the wind generators the advantage is that while they are not of power if you are in a windy place they generate all day and night
for the solar pannels have you though to put them vertically in a south facing fence if you have it? that helps a ton in winter (and funny enough is cheaper than aesthetic fences)

>>2910507
Yeah, I guess our place just isn't windy enough. If you could go like 50-100m high it would probably generate 24/7 easily, but at ground level no chance.
>south facing fence
Ironically our property actually faces almost south, which means the roof is perfectly angled for panels, but there can't be a fence in front because it's our driveway entrance.

>>2910500
>Even Victron uses around 20-25W standby
Yeah but some models have an "eco mode" that drops it down to around 5w when you're not using anything. That would be good for night time.

>>2910579
Yeah but for the additional cost of a Victron inverter, you can buy a whole extra 16kWh battery.

>>2910668
I don't want a victron inverter in the first place. I heard they're made in India.
What would be ideal is if the chinks made an inverter that cloned the "standby mode" thing so it doesn't just guzzle 50w of power all night when not being used. I can't just turn the inverter off completely either because then the fridge would warm up.

>>2910676
maybe have a 350w inverter for the small important loads? that is kinda what i do right now
(bc for now is what i have)

>>2910504
>scaling up multiple orders of magnitude from the tiny lithium cell in my phone doesn't make anything more interesting viable
It's because we're after electricity AND long-term storage. That's the hardest combination when it comes to energy storage.
If you wanted to store heat energy, an old 50 gal water heater @ 60C temp difference will store something like 12 kWh. If you had a ton of extra solar panels, you could literally wire them straight to electric water heaters and then use that water for home heating at night.
Conversely, short-term electricity storage isn't too difficult. A flywheel can store a decent amount of easily-convertible energy, but it's only practical for short periods of time. Unless you have it in a vacuum enclosure and riding on frictionless magnetic bearings, it won't stay spinning for very long. Capacitors can store electricity quite well and dump it immediately, but not a lot of it.

So that leaves us with chemical batteries, and being home users, we're at the mercy of economics. Stuff like vanadium flow batteries would be super cool, but building one of those is a bit beyond DIY and more into the citizen-science category. It is absolutely possible to make your own lead-acid batteries and if I had a supply of very cheap or free lead it is certainly something I would consider.
LiFePO4 is just so good now though. Massive manufacturing has made them insanely cheap, they last for thousands of full cycles, they don't readily explode & catch fire, etc.

>>2910676
Really, if you're not space limited, just work around it with more panels and more battery. If that's not an option, then get a small inverter that's always on for your fridge, and turn on and off a big inverter.

anons how do you crimp mc4 contectors on the cheap?

>>2910763
Get a cheap crimper.

>>2910764
i mean to ask like, are cheap crimpers decent? what is the minimum? bc i know some of the cheap crimpers are really bad for certain connectors.
I have a cheap generic crimper from lidl, looks like picrel, and one god one from facom that is for barrel connectors.

>>2910763
bite em'

>>2910767
As you can see in the picture, that is a wire stripper. The crimper function is specifically for crimp terminals with color labeled insulation like pic related, and it's not especially great for that, either.
Buy an IWISS crimper from aliexpress, they are a reliable very-budget brand.
https://www.aliexpress.com/item/1005006102116399.html This has precision machined die and is swappable, so you can buy other types of crimping dies for it. Also have it in kit with those plastic wrenches for mc4, though you can buy them separate just as well https://www.aliexpress.com/item/1005006226476510.html

Fixed an error on rentry. I never bothered comparing Na-ion specs, but apparently it's quite a bit worse than LFP on round-trip efficiency and it has a retarded voltage curve. So it's not just a matter of cost, it's a straight up worse alternative to LFP.

>>2911145
you saw this video no?
https://youtu.be/RO2I9911Mms
i think some of his info is outdated, but cannot prove it

>>2910891
any reason to not go to this kind ?
https://aliexpress.com/item/32848604198.html?
it has the conector support thing, i can get at amazon at almost the same price, and lower than ali
they do use the same kind of swappable jaws no?

>>2911157
The numbers seem to be a bit off, 75-80% on Na-ion seems extreme, and 99% on LFP also seems extreme. But the voltage curve really destroys Na-ion, 2V to 4V is fucking retarded. You'd need to spec your cables to double the amps even, if you wanted to draw a specific wattage.
>>2911162
More expensive but otherwise probably better.
>they do use the same kind of swappable jaws no?
It looks the same, but there are multiple types with various thickness and hole spacing so it's hard to say if it's compatible just by looking at it. Having the same model number though, it probably is.

>>2911179
>But the voltage curve really destroys Na-ion, 2V to 4V is fucking retarded. You'd need to spec your cables to double the amps even, if you wanted to draw a specific wattage.
man in ac shit is designed for 90 to 240... is not that big of a problem seriously, is just people are not used to it
as ofr the voltage. honestly using low voltage seems more a meme than anything else, the sub50v is safe is bullshit when most isntallations are done by paid profesionals. i get a segment should be able to self do, but that you cannot find shit for high voltage dc ?

>>2911189
It is a big problem when you buy a 15kWh battery pack and then it turns out you can only use 10kW because the 48V rated inverter cannot go from 30V to 60V. Likewise a 200A BMS or fuse can handle 10kW going through it if it's a 45-55V LFP, but only 6kW at the low end range of Na-Ion. Neither LFP or NaIon 48V packs are technically low voltage anyway, since they go up to 60V-ish.

>>2911194
you only consider nominal voltages for the low voltage limits, not the peak voltage, i know is retarded
i use 240v ac as context
what i mean is using plus 430v dc, as it will simplify a ton the fucking inverter, it will just need to chop the sinewave, need way less wire size and everything, and it wont be that more dangerous than regular ac

>>2911202
LFP's nominal voltage is 3.2V so the 16s pack is 51.2V, but for safety considerations you logically use the peak voltage, not nominal. Apparently there is a clause that allows up to 60V to be considered low voltage in specific scenarios in the US, and in the EU the low voltage directive limit is already at 75V DC.
DC is inherently far more dangerous than AC because the jerk locks your muscles in place and doesn't allow you to let go. 480V AC is already decently dangerous to begin with. Otherwise HV batteries and HV inverters already exist in theory, most commercial installs nowadays use HV batteries, only that they aren't truly HV because the battery banks are still 48V, at best connected in series, and then ran through a step-up converter. Tesla is maybe the only true high voltage battery with stacked 21700 and 18650 cells inside, everyone else uses converters.
Also I wouldn't personally want to assemble a 400V battery as /diy/.

does anyone want to guess which brand inverter has its LC tank tuned to this frequency? may be a little schizo but i dont think its a coincedence.

If I have a ground mount solar array a distance from the house, is it ok to put the negative wire of the panel strings into a rod bashed into the ground and only use copper wires for the positive? Will this work or will it lose too much power? I have clay soil and I'm fine with driving a bit of rebar or something 0.5-1m into the ground.
My panel strings will be between 150v and 200v.
I hear they sometimes use the ground as the conductor in AC transmission lines in remote areas.

>>2911412
Isn't even remotely okay. Nevermind one wire, you need 3, 2 isolated DC conductors and 1 ground potential equalizer, plus a lightning rod pounded in next to the array (which connects to both the panels and the ground cable). If you only have a small ground mount made out of wood or something else non-conductive, you can get away with ignoring all the grounding and lightning protection, though it's still not going to be up to code since the panel frames should be grounded, but it's realistically not a major issue.
Other than introducing serious noise into the line, being a major electrical safety risk and possibly fucking your inverter, you'd see varied but major losses depending on soil moisture. You'd definitely need much more than one shitty rebar pounded one meter deep. With 2.5m 16mm copper electrodes, the power loss is estimated around 15-30% based on soil condition. And then the DC current would probably corrode your rods over time. The PV cable is probably a lot cheaper than driving 2.5m 16mm copper electrodes.

>>2911395
SolarEdge?

>>2911209
there is no need for assembling the batteries that way, lets say that you have ten 48 batteries, the connections to make them 480v could be only inside the inverter where there is unsafe voltage levels anyway

>>2911431
I see. I read the relevant info in the rentry and it makes sense.
Well, I don't really need to penny pinch on wiring, it was just a silly idea.

Now I get to figure out a proper way to mount them

>>2911550
Lotta panels, what did you get?

Incidentally I bought a EEL battery box v5, only has one critical safety fault and one mid-level safety fault and both are easy to fix, so it's pretty good for chinkshit. Might make a video later, though I won't be assembling any time soon since I'm waiting for nkon to stock something cheap.

>>2911553
JA solar used ass 315w panels for 14¢/w

>>2911433
lmao, yeah.

>>2911550
nice! ive seen a "legit" commerical field where the entire array was layed on the ground with a cinderblock under one end for the angle. just gotta keep the grass short, or better put gravel down.

>>2911656
Yeah wind would un-solar that so I'm going to figure out a better plan.
I just today figured out that my fucking charge controller can only take up to 260v so that is all fucked because now I can only run strings of 5 or 4.
So my plan was 6x6 grid on the roof but now I either do that but get very jank with the wiring or I switch to 5x7 which idk if I'll fit that much.

My entire thought process was well it does 146v battery side surely it will take like 300 but no

Would you guys feel safe with using this variant of chinkshit breaker as the main protection for a 48v system? In addition to the BMS protections of course. I don't particularly trust some random transistor in the BMS to be able to stop shit from burning in case of a short circuit.

>>2911983
That's the best reasonable thing you can get for DC breakers/main disconnects. I'm also using that. If you get a name-brand one, it costs 3-4x as much. However, you should add at least one decent non-chink fuse, NH00 Gg or something like that before the breaker, it's like a $30 expense with fuse holder.

I’m just having fun with an anker 521 while I renovate my house, I have it in a cabinet with my laptop, homepod, everything I charge, would love to feed it from solar.
It only accepts 65W from solar (11-28V = 5.5A, 65W Max), however they ship the thing with a 100W panel (28.5 open circuit, 4.5A)
Guessing I can find pretty much any panel I want in that ballpark, as long as the open circuit’s not above 28v
With anything else in electronics I laugh at kids saying “not too many amps on supply it’ll explode!!!” but ai was wondering if I found a, say, 200w panel that kept under 28v, would that be fine, or are MPPT controllers cranky when working with such drastically oversupplied panels?

Panel will probably be around 20 feet from the battery, any major considerations I need to worry about for this, or will power drop be negligible?

Finally, I’d like power monitoring on this (battery doesn’t have any telemetrics, its pretty basic)
Was thinking some sort of current clamp on the DC/solar input just before the battery, also measuring voltage, so I can establish power. Would then brodcast over MQTT/home assistant via an ESP.
Happy to DIY this, just curious if anyone has any recommendations for power monitoring at this voltage range

Have a professional installer visiting for a second time on Tuesday to tell us what he might do for us, taking bets on weather it will be "90% gets paid for in grants/subsidies/depreciation" like he was talking it up to be or "it costs 100k, plus tax and tip". Surely someday it's gotta get inexpensive like the environmentalists say right?

>>2911983
>Would you guys feel safe
No. I do buy chink shit a lot but never anything that's made for safety and protection purposes.

>>2910676
Use a dedicated inverter for the fridge and let the fridge decide when the inverter should be on. I do this with an arduino and a temperature sensor but it can be done in many ways.

>>2912148
You're at such low volts and amps that you could just use a shunt.
>>2912240
There are people writing about them on diysolarforum https://diysolarforum.com/threads/dihool-dc-breakers.79969/page-2 and some of the brands are evidently well made. But chang changs, so if you don't open it up yourself, and even if you do, you should add a fuse on the line.

>>2912226
One very mild trick you can use is to get them to install a LV battery-compatible hybrid inverter, but don't buy batteries, say you'll buy them later, then /diy/ the battery.

>>2912263
He actually told me about the retarded law in some locales about the required minimum number of batteries, and they will install a unit with no batteries and a very simple plug so you can plug however many in yourself. Makes me think they're one of the good ones.

Why are my full batteries 12.9V? I read 12.65V is 100% for flooded lead acid at 20 celcius or so. This is even after a few hours of light load and no sunlight. I'm making a state of charge indicator. Anyone else having these voltages?

>>2912268
That might not be entirely retarded, depending on what it says, since using a battery that's way too small will expose it to much higher C-rates than it would be necessary/appropriate, but then, making this into law and regulation is very excessive.
>>2912276
There are differences between manufacturers, you should refer to your own batteries' specs. Even then, with lead acid you don't exactly have to fuss over having 0.25V more or less. Just have your charge and discharge voltages set correctly.

>>2910891
thanks anon, i only did for now a couple conectors but it works waaaay better that what i tried before
got this one >>2911162

>>2912498
Yeah, unfortunately if you ever want to crimp a connector, you always have to fork out for at least mid-grade crimpers or jaws. It's the same for all the XH and PH and ferrules and all the other shit. At least IWISS is pretty cheap.
If you're doing solar, best prepare a hexagonal 16mm2 ferrule crimper as well. As I've recently found out, it's nigh impossible to properly wire SPDs and lightning protection without one.

>>2912501
the nice thing is that i could just buy more of the jaws for my usecases. I have inherited a good facom one for ferrules.
i have a big crimper too, the kind that looks like a chaincutter, not the best shit ever, but it works

>>2912226
For anyone interested, it worked out to about 90k for 32kw, roofmount. 30 year warranty for the panels, 20yr for inverters, 10 for workmanship. After incentives, depreciation, and grants, price can be immediately reduced by 80%. Depreciation can be taken on taxes 3 years in the past. Any additional electric work like replacing old boxes or running more line can be tacked on and get all the discounts. All panels etc would be made in the US. In my area, the utilities won't buy the power off you but will give you 80% credit for it.

>>2913641
Pretty insane price, if you did a full /diy/ then it'd probably be about 15-20k in parts. But with the 80% reduction, you get the same thing with install and warranty, so it's not a bad deal.
How did you arrive at the 32kwp figure? It's a large system for residential.

>>2913648
It's actually a medium sized farm with two power circuits, "residential" for single phase and industrial 3 phase. We have a seed cleaner running on the 3ph, and grain milling and seed mixing businesses on the single. No way am I going to DIY something that expensive and likely to kill me easily, that's reserved for the 3d printer.

anons, i just want to power a small 100mm fan that vents a shed to avoid moisture buildup
ive read the OP, but its a total overkill
can someone suggest a small kit that can power a usb fan? preferably from amazon or somesuch

>>2913856
They sell solar fans that run directly off the panel. If it's a 10W 5V fan, buy a 10W 5V panel. That's all if you're fine with the fan only working when sun directly shines on the panel. If you want to have a continuously running battery powered fan, then maybe look for mini power stations, or powerbanks that let you plug in a solar panel.

>>2913857
can i connect one in the picture to a powerbank, and connect a ventilation fan to a powerbank?
what if i plug 3 solar panels in a single powerbank - will it charge faster?

>>2913884
Probably
Yes, but you have to splice the cables.
The question is the smart shit the panel may have and the power bank has, ideally neither are too smart, and then the thing works. Maybe look around a bit for better deals on solar panels, but these low-voltage panels are all horribly overpriced. You could buy a used 200W panel for $20 tops, only that it'd be 20V-ish and you'd have to convert the voltage.

Is this going to burn my chicken coop down? I have a 25W 12V panel going into this and then have it running a few little 12V fans. Working at the moment, lol.

>>2914168
At 25W it's probably gonna be okay.

>>2914168
i mean the wiring looks to thin for me to be comfortable, it would probably be ok, but i would change it to whatever thicker srap wire i have around

>>2914175 >>2914168
also add car fuses

>>2914168
Nothing ever happens. But what you will do is eventually kill a cell or two without battery balancing.
At 12v if you are charging at most to 14.6 that's only ever ~3.65 per cell you are effectively charging them to 15%. Each cell is considered full at 4.2 for at least the ones on the right.

I would suggest removing the li-ion cells and buy some LiFePO4 18650 cells and put them in instead. You will have much better performance and it's drop in for 4s setup on shit meant for lead acid

>>2913884
Yes, no, yes.
Almost all power banks don't allow you to discharge while charging, so your fan will only run at night

>>2912276
>I read 12.65V is 100% for flooded lead acid
and you will have read wrong.
It is actually 12.9. Though they quickly self discharge down to 12.8-12.85

orange man tariffs forced me to buy my solar system now rather than wait a few months like I had planned.
whole system cost me like $13-14k...

>>2914334
Well if you're buying fucking Victron then it's gonna cost an arm and a leg.

>>2914336
I'm hooked on victrons software. I cant go back to chinkshit buggy software or crude lcd screens

One day I'll spend like 1k on safety and stuff

Do you guys keep your batteries, inverter, charger..etc inside your home or do you have a solar shed or something outside?

>>2914428
Do you fear electricity or something

>>2914432
I just worry some chinkshit breaker is gonna catch fire and burn my shit down

>>2914435
Then don't buy chinkshit breakers, they need to be in steel enclosures anyway, they are always fire rated.
You can have 600a go to shit in a steel enclosure and it will be fine because shit is rated to do that

>>2914334
I missed the cheap solar panel deals -_-. Hopefully some of those $50 adani 335w ones come back so I can build a couple strings worth for $.15 a watt.

Got my 2x JK BMS's in before the deminimis door closed. Hopefully these $66 gotion grade A- cells dont suck.

>>2914395
you have a chins battery?
my sides are in orbit

is that a capacitor bank? why do you want one?

>>2914395
Please cover the battery terminals with plastic or something, you're one screwdriver away from housefire.
>>2914428
I have it in an outlying small room, converted patio. Another one I'm installing in a masonry wall separated basement.

>>2914499
>why do you want one?
It significantly improves motor starts.
Whats wrong with chins? I bought it because it was cheap, it's normally full and is only used when pulling more watts than the dcdc can produce, or the main pack is turned off like to work on it
>>2914542
Or simply don't drop shit on the battery

>>2914545
do you use dc motors or is only for the motors in the inverter? how did you size it?
it just funny to me, to buy a chins, its like the most chink shit name ever

>>2914558
What? No, like anything with a big motor plugged into the inverter, like a saw or something.
The capacitor bank limits the 12v droop on startup of the 120vac equipment. The inverter will gladly pull up to like 300A from it briefly.

Adding a supercapacitor bank to most 12v inverters gives them balls, it makes them seem a lot more powerful, especially on lead acid bullshit in a vehicle.

My neighbor's solar array collapsed in the snow a few winters ago and he gave me the surviving panels. The problem is there's no label that states anythign about the electrical properties of the things and he never came back so I could ask him about it and I've just been sitting on them for some time now.
I can multimeter the leads in full sun for a voltage reading but beyond that I know nothing. I'm no sparky, my multimeter sees most use as a continuity tester but little else. is the output on these things fairly uniform by the dimensions? My buddy has an array that has panels of identical dimensions and actually have labels, is this valid data?

>>2914696
are they bifacial?
or did someone peel the tag

>>2914734
There's just a barcode tag

>>2914696
you can sort of guess by the dimensions and even better with the year

>>2914760
>>2914696
but you need to check how they are conected internally, you need to count the cells and check if all of them are in series or in parallel, that kind of stuff
but with the dimensions and how its conected you can know most of the stuff. check the diodes box

>>2914696
Measuring the OCV in full direct sun is good enough, that's the maximum number you're dealing with. When you know OCV and surface area, you can extrapolate current/wattage. Two panels of the same size can have different voltages and currents, but wattage will always be about the same.

>>2914793
>Two panels of the same size can have different voltages and currents
And this is a matter of how the individual cells are connected up on-panel, correct? I haven't compared that against the known panel but if surface area more or less directly relates to wattage, they're probably 270w
>>2914761
>check the diodes box
Not sure what I should be looking for here though

>>2914871
>And this is a matter of how the individual cells are connected up on-panel, correct?
Yeah. You don't have to think any further about it than measuring the open circuit voltage, because it doesn't actually matter much how much the wattage is as long as you can ballpark it. The inverter can always limit its current if it really needs to.

>>2914871
>Not sure what I should be looking for here though
the black box in the back, where the cables start, open it, changing the diodes allows to change the working voltage in some cases

>>2914887
I knew where you expected me to look, but other than the basic premise of how diodes work this seems above my paygrade.... I have four bus bars with 6 diodes, laid out as two diodes between adjacent bars.
But I will note that if I do a little reading I might be able to tweak the output although hopefully I don't have to.

A Question that's been Eating at me...
How do I Charge a LiFePo4 Battery with a Solar System that already has a Battery in Use?

I Have a 50ah Battery I Use for my Solar System and I have a 20ah battery and 15ah Battery I would like to charge.

Without putting them I parallel, what steps would I Take?

I feel like this is a simple solution but my ogre brain doesn't see it

>>2915556
you will need to be more specific on what do you actually want to use them, like why you dont want to put in paralel, bc the answer will be diferent

>>2915557
>picrel Solution

I don't want them in parallel because they are different Amp Hour Ratings

I think Paralleling a 15ah and a 50ah battery, both batteries would only max out at 15ah I think

Plus the internal Resistances maybe be off between the batteries leading to a never ending power waste of cells balancing out

>>2915558
Actual Picrel Solution, Dumb 4mb limit got me

>>2915558
>I think Paralleling a 15ah and a 50ah battery, both batteries would only max out at 15ah I think
You might want to learn baby-tier basics of electronics before messing with high current batteries. But rest assured, you're wrong about everything and there's no issue putting two batteries of the same voltage in parallel. However, they should be around the same state of charge when you connect them, i.e. if the 15Ah battery is discharged, then your 50Ah main battery should also be on the lower end. Obviously both batteries should have the same rated voltage, i.e. 4s/8/16s LFP batteries, do not combine different chemistries.

>>2915572

I Should have paid more attention in Electronics Engineering Class hahah

But essentially, I use my smaller Amp hour batteries for Running off site devices and then charge them using grid.

Would prefer to charge when I'm getting Peak Sunlight and my 50ah battery is Full.
Would be better to get every drop of sunlight my Panels are Pushing rather than being Dormant

>>2915577
If you connect it in parallel in the morning, then both batteries will charge up from the sun. The only reason you shouldn't connect it to the full battery is that the inrush current can be pretty big (~400A) and unnecessarily wear down the smaller battery with rapid charge and shoot sparks everywhere when you connect it. Could possibly ruin BMSes if you have shit BMS or burn fuses.
This thing >>2915559 will work and might be the easiest solution, it's just unnecessarily expensive.

>>2915577
man disconnect the 50ah when is full, connect the charger to the other two and when all are full connect them together
you are overthinking this shit

>>2915579
The Device is Made Specifically for the Bioenno Batteries I use

The CEO is the dood that tells me not to connect his batteries in Parallel.

He keeps referring me to the Manual.

>>2915793
>if a single battery of equivalent size can be used instead
So you can parallel.
>only connect batteries of equal state of charge in parallel
What I said.
>equal internal resistance
This isn't going to matter in your case, you're better off not fiddling with resistors to match internal resistance. You probably can't even measure it to begin with, since they probably don't let you into the BMS. Either way, if you're worried about it then just do >>2915584 or >>2915559

>>2914266
It is working for now, at least it turns the fans on and runs them for most of the day. This is kind of just a trial, I have a bunch of old 18650s that I don't use anymore so I figured why not.
In the future I would like to have this power a light of some sort that turns on at night, and then knows to turn the fans on during the day or something. IDK just starting out and experimenting a little.

>rv freedocking on 15 amps
>summer approaching
>need power for AC
>1s2p 48v 100ah EG4 with a 6000xp All in one solar generator
easy day

Here's a project I'm working on. It's a solar array that also catches and stores water. I'm going to mount the panels with the frames touching, then hang a gutter and run the downspout to a series of IBC totes under the panels.

>Bifacials $70/590W from the factory in China
>$300 dollar from local store

These cunts are making a killing, middlemen vampires

>>2916132
Right now probably also tariffs, but yeah, many sellers use massive margins since they count on selling to idiots.

R8 my setup from a 100w panel

>>2916263
It's a thing/10. You can upgrade to Wayne/10 if you don't have a charge controller and the panel is directly on the battery.

>>2916272
There's no charge controller. I've been running this for a year to charge all my battery packs and devices without any problems.

>>2916273
Alright, then you can be certified Wayne. Though I guess it's still better than having a garbage charge controller and then melting it with overcurrent.

>>2916263
I've used that inverter before. They don't last at all, unfortunately

>>2916331
I've had this one for more than 5 years and haven't had any problems with it. I used it to power a laptop and tools from my vehicle before using it in this setup.

I think I will end up bolting them together so that I can use another of the bus bar things to connect the two together. It doesn't quite reach now

>>2916086
shouldn't you be worried about heat expansion/contraction?

How practical is running a solar setup for fridge/AC without batteries?

>>2916864
Unless you live in Ecuador on the Equator, Dont even Bother.

The Logistics of Getting enough Panels Together to operate a fridge for the period of daylight is Ridiculous as all get

>>2916865
Really? A few solar panels and an inverter doesn't seem too crazy to me. the whole thing would cost like 2k max

>>2916870
Is it Doable?
Yes.

Is it Viable?
No.

No Batteries Means if one cloud Passes over your panels and cuts the Watts, the Fridge will power off.

With a Shit ton of panels you could get away with it but unless you live in a windy Area and have Wind turbines to keep up your Inverter at night, the Fridge will be off during night time or Thunderstorms

>>2916874
Yeah I know that the clouds would stop the fridge, my hope is that it'd be chilled just long enough until they pass out, and if there are a lot of clouds then it wouldn't be that hot or if it's nighttime. Im thinking about some small AC unit that'd be able to run, imo it's more important than the fridge. Also by fridge I actually mean refrigerator.

>>2914696
Count the cells. There are usually 72 cells in an older panel (sometimes 62 or 96). The math is easy is a rectangle so 8x9 or 12x8 or etc. If its a 12V panel its likely 36 cells. Each cell is .5V open circuit. The current you can estimate (very roughly) from age and a new panel rating, old panel maybe half of the specs of a new one. MPPT current? IDK your controller should find that if you're doing some home bake try for 80% Voc? Look at some MPPT curves on google images.

God forgive me for what im about to do...
https://www.aliexpress.com/item/1005007618390182.html

>>2916883
What.
Wait, what is your end goal?
What happens at night?

Fridges, a/c, ect. All cannot be used like this. If you unplug a running fridge, the expensive ones will wait 30 minutes before trying to start again, and the cheap ones will try to start up again and not be able to due to operating pressures and either fail safe or burn up.
The compressor in the fridge compresses stuff, and then when it shuts off, the pressure slooowly lowers back to normal. While the pressure is still high from just running, it cannot start from off.

>>2916870
>2k max
For 2k you can easily make a system with large batteries. You can do it under $1k even.
>>2916891
>1PCS 48v 13S2P 20-60Ah Lithium Battery
>750Wh 50Ah 48V
That's going to be terrible at that price, from aliexpress. Probably 48V 3-5Ah, or it will quickly return to being 3-5Ah if it starts off better. If you really need a small cheap 48V battery, you'd best build it yourself from known cells.

>>2916924
>For 2k you can easily make a system with large batteries. You can do it under $1k even.
how tf

>>2916916
well the idea is for the refrigerator to extend the food shelf life, main concern is hot summer days when the sun is blasting, during the night it's not that bad


>>2916924
>Probably 48V 3-5Ah,
yeah it's 6Ah max

>>2916969
>https://www.aliexpress.com/item/1005008936605047.html
$250 24v 3.2kW inverter
Pre-made 24v LFP batteries are around $400-$500 for 100Ah/2.5kWh, you can /diy/ a 6kWh 24V battery for about $500.
400W solar panels go for under $100 in most places, can go as low as $50, you need 2-4 depending on your location and expectations. Cables and misc costs are about $100.

That's the $1k version, for $2k I'd start with getting a good Deye single phase hybrid inverter, that'll cost about $1k, then $700 for a budget $10kW /diy/ battery build, same 2-4 panels. Beyond that, a battery box kit for $500 would be a good investment since it gives the batteries a safe place to live with easy/quick assembly, going for standard 280Ah batteries instead of cheap 200-230Ah ones would cost another $100 if you get a good deal, and then solar safety shit and wiring shit would add another $300-$400 if you wanted to get up to code.

Shipped to door to rural Central France
There is no cable, no structure, even no ac protection! But because I work in the field (100k panels to maintain globally on up to 70mw) I have many things for the more shy of you, you can see what alibaba has to offer
I didn't even bargained because I don't have the space right now but in the end it would be a perfect plant for me long term, I would like to share my electricity with my neighbours

15kwc ~1700x1150mm~ 36x425w longi
2x6kw in (dont know the brand but many sellers got it, I work mainly with Huawei and sungrow from the Chinese, the 2nd one being suspiciously very much looking like the 1st)
20kwh 50v 400ah lifepo no name
The breaker boxes seems way overpriced to me but I haven't calculated anything

>>2916995
>Growatt
Growatt is a very cheap brand, maybe just slightly better than the cheapest shit you can buy on Aliexpress. That said, you'd best avoid Huawei like the plague that they are on residential solar, even Growatt is effectively better.
>lifepo no name
If you're lucky, they're B-grade cells, if not, C-grade. Price is average.
>The breaker boxes seems way overpriced to me
By chinkshit standards, yeah, they probably have PV SPDs for $10 in there. Should cost $100 for what they are selling, for $250 you can get real CE-certified components and put together a combiner box that's up to code.

The DDP cost is suspiciously low considering that this is going by container through ports and you have a whole palette of solar in there.

>>2916916
>>2916969

You could maybe a small battery and find a controller with load disconnect/reconnect feature. The solar charges the battery and reconnects load at 90%, runs down to 20% when there is no sun and switches off the fridge, waits for recharge. Load hysteresis - it would switch the fridge off at least every day. Might not be too good for fridge although they do duty cycle in normal use.

>>2917086
Im guessing the best thing that could be done is spend all the money on a Pure Sine Wave Inverter,Solar Panels,Solar charge Controller. Run that for a bit till you realize yeah I need Batteries.

Then buy batteries and add to system

>>2916969
>well the idea is for the refrigerator to extend the food shelf life
So. You're running a fridge to keep shelf stable foods in a shelf stable temp range during your africa hot summers?
That sounds retarded.

Why do you people always have such retarded ideas and then pretend that grid tie micro inverters don't exist?

You simply plug the solar panel into your wall with a fucking extension cord if you're that lazy and then it supplements the electric usage of the fridge. When the fridge isn't running, it supplements something else.
It's so simple

>>2917088
I must be Retarded

A Solar Panel that puts out DC.

Plugged into a Wall outlet that Uses AC...

What.

I'm a Bioenno Battery D Rider, I want atleast 100ah of LiFePo4 but damn they are expensive, what is a Proven and tested Battery that I can trust?

Google is just riddled with Shills.

Redodo has a 165ah Battery for $350 at WageMart, some ham radio guy stands by it but he has also stood by other batteries too so it makes him look like a shill...

WHAT IS A GOOD BATTERY

>>2917091
He said microinverter. Panel goes into microinverter, microinverter goes into wall. This assumes you're on the grid. It's illegal and can fuck you over in many ways so what he said is not a good idea, but it certainly works.

>>2917095
Good battery is one you build yourself and you know all the components inside are good. If you want an already built battery, Will Prowse has many teardowns, watch those
https://www.youtube.com/@WillProwse

>>2917088
Anon are you retarded, I have no grid electricity in the mountain, and food spoils fast, that's why i need a refrigerator

>>2917098
I never said microinverter, I dont even know what that is

>>2917105
>>2917088 said microinverter, you know, the post he's replying to.

>>2917105
>I have no grid electricity in the mountain
Oh well why didn't you say that.
I also have no grid electricity in my mountain. I solved it by doing this >>2914395
You should try something similar
I think If I had to build a system just for the fridge it would only be the chins, the inverter on the wall, my other charge controller, and only 4x300w panels. Total cost ~1300

>>2917187
Thanks for the words anon, they are quite encouraging! I will run down the math and try to fit it all in under $1300. I have to think about the winter in my head, bcs right now heating is from a wood stove, but I really would want to put that on the solar system as well, even if partially warmed during winter. I have a 2.5kw oil radiator so im thinking about how to stich it together. Ofc the refrigerator wouldn't run during winter...

>>2917190
>even if partially warmed during winter
during the night*

>>2917190
Solar panels have very low output in the winter if you don't live near the equator. The only cheap-ish way to make them produce some decent heat is buying a split AC and using it in reverse cycle, that way you can get about 3x more heat out of the electricity you put in. Read the rentry and use the solar calculator https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html

>>2917193
Thanks very much for the advice, I will search for them in depth. Thanks for the link.

>>2917195
Burning 1kg of wood produces about 3kWh of heat, less if you have a shitty stove. So if you consider roughly how many kilos of wood you have to burn in the winter to keep warm, you can get an estimate of your heat loss, then you can divide that by 3 to get the amount of kWh you'd need to produce to heat with a split AC. A /diy/ split AC install would be about $800 on the cheapo end.
Everything else is on https://rentry.co/solarshit, or if you want to calculate heat loss the other way around (based on the building's structure), then https://rentry.co/insulationshit#heat-loss

>>2917198
Thanks for that, it really makes a lot of sense, I will read the rentry

>>2916863
>shouldn't you be worried about heat expansion/contraction?
theres a tiny gap

Rate my setup

>>2917490
There's space on your hood you're not utilizing.

>>2917490
can you list your stuff?

>>2917577
It's literally all in the picture
>Ecoflow Ultra Pro Goy 6gorillion
>overpriced portable solar panels
>solar cables+splitters

>>2903345 (OP)
has anyone ever thought of shaping a solar panel like a kite and then use a ballon to deploy the panels at an altitude with constant air stream?

>>2917622
What benefit would this have? Regardless of any potential benefits, the costs and risks associated far outweigh anything you could think of. It's far easier and cheaper to just place more panels on the ground and install battery storage than to do extreme solutions like flying solar panels or space solar panels.

>>2917502
I did use it later on. It's not terribly effective if the sun isn't at that angle yet. Wind blew one off too later because of the sloped surface. It survived.

>>2917577
2 Ecoflow Pro deltas, 4 400 Ecoflow solar watt panels, monocrystal, 1 River 2, 1 100 watt Ecoflow solar panel.

not solar, but inverter related
anyone can recommend an inverter that could be used with a lipo battery of 60v? my electric dirtbike has a 2 kwh battery and it would be good if i could use it to power some shit in the field
has anyone experience with less standard voltages? bc i cannot find anything from the big players i know

>>2917856
48V inverters can usually go up to 60V rated, where I'd assume they could survive some mild overvoltage, though if your pack goes to 72V then that might be pushing it. But depending on what exactly you want to power, it might be cheaper to just buy a small all-in-one solar generator.
Aliexpress has these chinsy pieces of shit that go up to pretty high DC voltages, maybe try one like this https://www.aliexpress.com/item/1005007940915149.html

>>2917859
>Aliexpress has these chinsy pieces of shit that go up to pretty high DC voltages
i know, but noone seem to be of any known brand, so i that is why i ask if some anon has dealt with them

>>2917579
I won't say they're overpriced, just over engineered. Water proof and probably can take a sledgehammer.

>>2917856
you can get step down dc dc fairly cheap related

https://www.aliexpress.com/item/1005005956158555.html
that work with a a normal car inverter. I use one for an electric outboard its not super demanding but there are no problems.

>>2917969
https://www.aliexpress.com/item/1005003861571665.html
A serious one suiting actual inverters not just laptop adapters.

>>2917969
>>2917999
funny enough my current system is to use a 60v to 13.something converter to charge an intermediate 12v lead stationary battery that i sue with a hacked old ups unit, bc i had those lying around, but is anything but portable, and is not giving a ton of power

>>2916995
Those panels are disgustingly cheap.

>>2918995
That's the normal price without tax, if you're paying any more for panels, you're getting scammed by middlemen.

>>2919008
I'm not the guy you're replying to, but if I were building a chink system I'd start with a few panels just to see if they're any good and then if it's all good then go ham on the rest of them.

>>2919032
There's effectively no such thing as a non-chink system. Longi panels are fine, unless the alibaba seller scams you and sends you used/damaged panels. Usually it's better to search locally for a China-direct seller that has decent prices, because you'll waste a fuckton of money trying to RMA something with chinks, especially via alibaba.

I've wanted to design my own MPPT load controller for a solar panel for years now. Note: not a GOOD one, not a commercially competitive one, just one for my own education and edification.

finding info on the low-level circuitry of an actual, basic MPPT is surprisingly difficult. We're trying to maximize P=VI=V^2/R=I^2/R, that's simple enough and there's multiple algorithms to do it using a microcontroller.
But then at the lower levels that actually implement the circuitry, what the hell happens?

We can vary the power delivered by using a variable shunt load (say, a power FET) to vary the resistance seen by the panel, but that's fucking stupid since you're just burning the excess in the FET

I've seen mention that the "variable load" is actually a switched-mode power converter, but then I get lost as to how the power converter varies voltage? current? resistance? to maintain the maximum power point

>>2919048
>=I^2/R
=I^2*R, my bad

>>2919048
It varies voltage/current by PWM. The voltage through the MPPT is typically lower than the OCV of the panel, so it's usually a step-down PWM. The difference between a simple PWM and an MPPT is that the PWM doesn't care about the panel, it just manages total voltage/current for the battery, while MPPT tries to optimize the PWM to pull the most out of the panel by monitoring the peak point and adjusting the PWM driver. Going about it backwards, limiting the current going through the PWM controller into the battery/capacitor/whatever can increase the voltage and thus increase the total wattage, or vice versa, the MPPT just tests a bunch of values until it finds the best one. I'm an electronigs retard though so this might not be entirely correct.

>>2919055
Alright, that makes sense along with what I'm reading now. My microcontroller will use its MPPT algorithm to vary the switching PWM of the power converter in order to maximize the delivered power, closing the feedback loop.
Cool. Time to learn about implementing my own buck converters.

>>2903345 (OP)
>picrel
What does Hybrid do exactly? Use solar power from the battery, except when there is none, then use power from the grid? If so, isn't the difference between that and Off-Grid minimal?

>>2920265
The difference is huge, because when you're off-grid, the battery runs out, you have no power. Also not all hybrid inverters have UPS and hence can't work off-grid, in fact many of the most popular hybrid inverters tend to not be able to do UPS.

>>2920282
>you're off-grid, the battery runs out, you have no power
I meant that isn't off-grid just the same equipment as hybrid but without grid connection (provided it has ups)?
>hybrid
Can a hybrid system do absolutely no export to the grid (i.e., not even small amounts)? Also which brand of a hybrid inverter is good, I opened the page that is linked in the op image, I'm under the impression that Deye/Sol-Ark is the best, is that correct?

>>2920283
>I meant that isn't off-grid just the same equipment as hybrid but without grid connection (provided it has ups)?
Yeah, potentially. Deye and Victron can work off-grid, but many hybrid inverters can't, that's one of the reasons for the distinction.
>Can a hybrid system do absolutely no export to the grid (i.e., not even small amounts)?
Theoretically yes, but I'm not sure how precise this is. Like Deye definitely has a setting for how much to export, if at all, and you can turn it to 0, and then it shouldn't let any power out, but this is subject to the precision of its regulation as well as setup, because the Deye can provide power to its UPS load, which is separated from the grid, and the hybrid load, which is directly connected to the grid, but is monitored by current clamps. The hybrid loads definitely let some current escape here and there, but it should be miniscule amounts. Then again, nothing is stopping you from putting everything on the UPS, and then you shouldn't get any leaks.
>brand
Deye is good, especially in value, you get a fully featured hybrid system for the same price a shitty Huawei hybrid costs. Victron are better, but almost an order of magnitude more expensive than Deye. If you're in the US, then EG4 is also viable.

>>2920291
>Theoretically yes, but I'm not sure how precise this is.
Is that any different for off-grid inverters?

>>2920295
Well if you have an inverter that inherently cannot send power in one direction, then it won't. I don't know how exactly Victrons are built, or how others are built, but I'd assume that if it's an inverter that doesn't have grid export function, then it definitely can't send power into the grid. Issue is that some of the simpler inverters will also not have the grid passhtrough option, ie. when your batteries are empty, you can't automatically switch to pulling from grid. But this is really specific to each single inverter.
The way all-in-one units do zero export is that they create a constant draw of like 20W from the grid (which is on top of the normal self-use of the inverter) to very seriously reduce accidental export, but this still doesn't completely eliminate it, since it's controlled by a feedback loop.
But again, if you just connect everything to the UPS port of a Deye/Solark, and disable grid export, then it will not export anything. This is only a problem if you also have hybrid devices, like I have my heat pump on a hybrid connection because I don't want it to drain my battery reserve in case of a power outage.

I had some retard try to tell me I shouldn't charge my battery up until the bms shuts off input.
Is that right? It makes sense on smaller bms's but this thing is higher voltage, 40s. Still mosfet based I think or something silicon. Would it not have freewheel stuff and snubbing? I think it would fucking explode the first time it shuts off without it surely.
My shitass charger doesn't quite let me set a voltage limit. It does but seems to just ignore it

>>2920423
What battery do you have? If the BMS is set up correctly, then it should be fine reaching the top. If you have any top balancing setup, then it will naturally turn on and off as it top balances, so it's necessary that the inverter/charger delivers fairly high voltage.

>>2920424
Lifepo4. Bms shuts off the input mosfets around 142ish but the charger likes to sit around 144-146.
The thing is both they and chatgpt say it's bad because it's suddenly switching off up to like 5A which I find hard to believe is not protected with this kind of voltage tolerance.
There is no active balancer, it's passive, 30ma~

>>2920425
It'd have to be a really trash BMS to get upset by turning off 5A. If you can configure the BMS, you could let it go to 144 since that's still only 3.6V/cell. If the current is within the BMS ratings and the voltage is within LFP ratings, then there is no major issue, and then whether the repeated shutoffs cause any problems depend on how poor quality the BMS is. A good BMS should be completely fine with it.

anons i need a cheap solar MPPT for 100w solar panel output rated for 12v 10A (max draw will be like 6A) that would work without a battery from aliexpress

>>2920557
i dont have a proper recommendations, i buy victron second hand at chink price to retards, but at least put some caps in there, or a cheapo or old battery. shit doesnt work properly without any of that acting as a buffer

>>2920557
>without a battery
What exactly are you visualizing here? An inverter that produces AC from the 100W solar panel?

>>2920564
>>2920557
no, it's actually a purely DC system, it powers a 60W diaphragm water pump with an arduino and an antena

>>2920567
What do you need the MPPT for then? Just connect the panel to the water pump and let it be.

>>2920575
yeah but i need a 5v output for the arduino, and the mppt has one

>>2920592
I could use a buck converter for the pump to step it down to 12v, perhaps I could use one as well for the arduino, but it gets complicated

>>2920592
I don't think you know what MPPT is. You'd indeed normally use a buck converter, but the arduino can take up to 20V input since it has an internal voltage regulator. What are you stepping down from the panel when the panel is 12V and the motor is 12V? Motor should be directly connected to the panel unless you want to modulate RPM, arduino could be connected to the panel directly as well, though in most applications you'd probably want to have a battery at least for the arduino, so it'd be panel -> step-down -> battery -> arduino.

>>2920596
Sorry for the confusion, the pump is 12v but the panel i'd be getting is 18v this one https://www.aliexpress.com/item/4001199129786.html
I indeed want to be able to control the rpm with the arduino via a radio remote with a knob and on/off button. I'm trying to avoid using a battery because it's a fire hazard and i most likely would leave the panel + arduino + antena high in he air on a tree and they'd get rained on

>>2920597
Well if you're okay with it only ever working in full bright sun. Batteries aren't much of a fire hazard, you can hook it up and then pot it in epoxy, put it in a case, and it'll never ever short.
That aside, you could go for a single step-down to 12V, connect that to arduino + motor and the rest. The motor could still be directly connected to the panel since your PWM RPM control is basically doing the same shit as a step-down converter, you'd just set the maximum PWM duty cycle to 70% in code.

>>2920597
you want an actual mppt with usb ? aliexpress.com/item/1005005557070255.html
get caps or supercaps at least, the surge of the motor will fuck up everything if not or may not even start.
But still you should know that lifepo batteries are pretty safe, and sodium batteries are completely safe

>>2920601
i might actually bend the knee, running the buck converters might be a little too complex. I might just run with the MPPT that comes with the panel and just use a 40w lifepo4 battery

>>2920610
I would go with a LTO based battery.

>>2920632
>LTO
that would cost me an arm and a leg, im thinking about good ol lions https://www.aliexpress.com/item/1005007342592879.html
but apparently i'd need a BMS so I have to figure that out as well

>>2920610
you can also use a pwm solar charger, if you want to cheap out. but you were explicitly asking for a mppt one
and again you could use a capacitor bank like this one aliexpress.com/item/1005008086616746.html (random example no idea how good it is)

>>2920697
What you linked already has a protection board, at least it says so. As an alternative you could buy a 12V UPS, something like this https://www.aliexpress.com/item/1005008100165910.html. Put a step-down between the input of the box and the output of the solar panel.

>>2920712
>pwm solar charger
>capacitors
thanks for the suggestion anon, i dont really understand capacitors that well so i dont wanna risk it, the solar panel comes with it's own mppt so i will just stick to it and the li-ions I linked earlier

>>2920753
I think what you linked fits perfectly for me, I was thinking of using a pack like that and just swapping the batteries each year or two, but what you linked looks really good, it even has a case so thats much much better and it has an integrated BMS, im will look more into it and will most likely order that one, thanks anon

If the project succeeds i will post pics in a few months of everything

>>2920802
after looking a bit more into that ups it's 12v is limited to 3A but the pump would draw 6A at max power, so i would have to get a different one

>>2920810
You can solder a wire on the main + and - terminals of the battery and connect the pump to that, through a mosfet driven by the arduino. It will still automatically turn off if the battery is discharged since the BMS of the UPS will turn off the arduino.

What panel type is actually good? Couldn't find anything about that in the rentry. Additionally, if I had unlimited money, what kind of panel type would the best on the market for rooftop?

>>2922169
There's nothing because all common commercial panels are about the same. You have a monocrystalline silicone half-cut panel and that's about it. Your choices are mainly bifacial or not bifacial, where bifacial is better free-standing but not better on a roof and maybe 30-50% more expensive.
High quality solar panels are still gonna be monocrystalline with maybe better build quality and more importantly maybe more bypass groups; more bypass groups react to shading better. But for any regular application, just decide what color you want between black and white-black, and find the cheapest tier 1 manufacturer-made panel locally.

>>2922185
i still find weird that bifacial is more expensive

>>2922190
I'm guessing it's the extra hardened glass and weight for transport that makes it more expensive, otherwise not much goes into either type.

thoughts on panels from alibaba?

>>2922433
You're probably not saving money compared to buying locally unless you live in Africa. But Alibaba Longhi panel is probably the same as locally bought Longhi panel.

>>2922434
sure but alibaba offers me the suppliers directly, i have no fucking idea what redneck decided to import chinese panels in my country

I got a 280Ah pre-built commercial battery and it turns out it's not enough, I'm trying to go off-grid so the daily battery anxiety is getting unfun.

It's a HIGEE 16S300. I want to get another one of the same model, but it's no longer being sold in my area, only the 300Ah model is available.
The shop told me I can't pair a 280Ah and 300Ah together because "they'll be imbalanced, the smaller one will be overcharged while the bigger one is still charging" but I don't believe them, I think they're just trying to get me to buy two 300Ah's.

I'll have to connect them in parallel since the inverter only has one set of battery I/O. Won't their on-board BMS's be already enough to regulate the charging even in parallel? Or do I have to buy an external BMS to measure out current for each battery; if that can work?

I tried looking through the manual and I can only find pic related that might imply that the batteries can talk to each other to regulate charging, but it might be just for monitoring.

>>2923332
>The shop told me I can't pair a 280Ah and 300Ah together
This is total bullshit. You can pair any size battery as long as the voltages and chemistries are the same. It's very slightly better if they are roughly the same size, but the charging inherently self-balances through the voltage even if one battery is 30Ah and the other is 300Ah.

>>2923403
Thanks man. I wonder what other bullshit solar power vendors try to get away with lmao

>>2923403
that's bullshit but sure.
LFP can actually lower in capacity without lowering in voltage a significant amount. you will have to get very clever with your bus bars and cabling to keep the setup passively balanced enough to survive your daily depth of discharge.
and if you do something incredibly stupid like 300 and 30, you very much should derate the overall pack ampacity because if your discharge favors the small one it has a significantly lower current limit.

>>2924588
You're not pulling 1000A from these batteries, and both batteries have a separate BMS for limiting the output current. So what if the 30A battery discharges first, slightly ahead of the 300A one? Nothing, the BMS keeps it at a safe voltage anyway, at worst it gets cycled a bit more than the big pack.
Of course we're talking about putting 16s1p batteries in parallel externally, not individual cells inside a battery. You could do it with individual cells, but it'd be pretty dumb.

is there a problem in using a 18v panel in 24v mode in the mppt or do i need 2 in series?

>>2924641
What 24V mode? You mean to charge a 24V battery, or that the MPPT is rated to 24V?

>>2924642
yeah both, the im considering upsizing the load to 24v from 12v to save on wires

>>2924647
Well the 18V panel will definitely not supply 24V, so yes, you need 2 panels in series, or one panel that has its rated working voltage above 26V or so. Working voltage, not open circuit voltage.

>>2924652
thanks for that, I thought it'd be stepped up by the mppt and just eat some current/efficiency. That definitely makes my life harder

>>2924655
there are some that does that, but may not be the easiest to find

>>2924675
yeah im looking for simple solutions so i will either get 2 solars or a stronger one

>>2924676
if i recall correctly some of the solar chargers for gold cars do step up, but i doubt is to 24v
also check your panel cell connections, it may be able to change the voltage in the diode box

>>2924680
>gold cars
golf lol

>>2903345 (OP)
>mppt
Are there any budget mppt you can stack or daisy chain as your array grows, victron is expensive. https://www.victronenergy.com/solar-charge-controllers/smartsolar-100-30-100-50

>>2925065
It's a fucking charge controller, it says so right there, "charge controller". MPPT, Maximum Power Point Tracking, is a thing the charge controller does, it's a feature, it's not the [thing] itself.
>budget
EASUN aren't total dogshit but you should still exercise caution and not go near or over the current limit, something like this https://www.aliexpress.com/item/1005008836684308.html

>>2925111

>>2925111
>it's not the [thing] itself.
Yes, I know. Why sperging out.

I'm suing the OutBack Power FM60-150VDC FLEXMax 60 Charge Controller. but it's expensive and I'm just asking for suggestions that I can add as my system grows. I have 6 24 volt 100 amp lithium batteries which is about 16,800 watts of storage.

Thanks for your suggestion. What if I want to charge 200 amps an hour. My system can take 300 amps an hour. I want something that grows. The outback and Victron can daisy chain but it's expensive. I guess you don't know. Anyhow, thank you for the effort.

>>2925164
You can connect any amount of any type of charge controllers to the same battery pack, provided they have the same voltage ratings and they all support the given battery chemistry. If you mix different brands, it can cause some mild inefficiency issues with different charge curves, but as long as it's the same brand, you can put 10 of them on the same battery for all they care. Of course this doesn't apply to the PV strings, each charge controller should have its own string. Ideally choose a type that has adjustable voltage thresholds for CC/CV/equalizing, the one I linked has that.

>>2925187
>You can connect any amount of any type of charge controllers to the same battery pack, provided they have the same voltage ratings and they all support the given battery chemistry. If you mix different brands, it can cause some mild inefficiency issues with different charge curves, but as long as it's the same brand, you can put 10 of them on the same battery for all they care. Of course this doesn't apply to the PV strings, each charge controller should have its own string. Ideally choose a type that has adjustable voltage thresholds for CC/CV/equalizing, the one I linked has that.

OK, this is very helpful. To summarize.

PV Array 1 to charge controller 1 and inverter to battery bank.
PV Array 2 to charge controller 2 to battery bank

Thank you.

maybe a new thread?

>>2925241
>>You can connect any amount of any type of charge controllers to the same battery pack, provided they have the same voltage ratings and they all support the given battery chemistry. If you mix different brands, it can cause some mild inefficiency issues with different charge curves, but as long as it's the same brand, you can put 10 of them on the same battery for all they care. Of course this doesn't apply to the PV strings, each charge controller should have its own string. Ideally choose a type that has adjustable voltage thresholds for CC/CV/equalizing, the one I linked has that.

It worked, thank you.

>>2926462
so i went and did the changed i wanted >>2926704