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Alcohol isn't the answer. Alcohol is the question. The answer is "yes!"

It’s called “solar” because all the good 4 letter words are taken.

I'll take this one step further: You will probably learn a LOT. The value of learning a valuable skill is pretty high for me.

After a while, people get tired of "saving money".

The red “paint” disguises the connections that are actually glowing.

I had a similar huge spark when i tried to use a battery carrier i made:

Hmmm, clickbait, this isn't free.

I was not expecting a "Buyer Beware" thread to end with seller being recommended. Me thinks "Buyer Be Patient" may have been more accurate. Just my $.02.

This is like the Polish firing squad... Ready! Fire! Aim!

My last diversion, on this thread.

This Morningstar Tristar MPPT 45 was insanely expensive (over $700) in 2010. But it has been a worker. 8 years with 330W of solar on my RV charging lead acid. The last 3 years, with 300W solar on garage, its been charging various lithium banks for the seed warmers, lighted grow house, quite a...

If you can measure your battery voltage, you can live by this chart unless you're living on the edge of squeezing every amp hour out of your battery. I live between 13.0 ("getting low") and 13.3 ("looks pretty full"). Don't overthink it.

http://www.solarelectricityhandbook.com/solar-irradiance.html Reducing energy needs thru efficiency is always cheaper and usually easier than more production.

I was thinking this too. I used to point a lot of folks to the www.mobile-solarpower.com videos and canned solutions. I think a lot of the products and overall system design have evolved so much that those are fairly obsolete. And, there is a lot more focus on a couple specific applications...

I recall someone once saying that "stupid is supposed to hurt".

3000W / .85 efficiency / 10V inverter cutoff = 353A Fuse should be 1.25x to 1.5x higher to prevent nuisance blows. 500A fuse a good choice. But since the fuse protects the wire, your wiring would need to withstand 500A and that is a difficult requirement to achieve. Looking at it the other...

Yep, you're not missing anything. All these things you mention are why I'm in my 7th month looking for a BMS that I like. I like 3.0 and 3.45 and am getting roughly 90% capacity. I need to be conservative too, because I am the BMS.

And the "ish" is proportional to the "mostly". In general.

You've heard of "FU money". This is FU power:

Too soon. RIP Pee Wee.

Planning ahead for the real SHTF? https://www.greenmatters.com/p/what-happens-earth-off-axis

You shouldn’t be charging without a BMS! Watch your individual cell voltages, YOU are the BMS in this setup.

41.2Voc x 68 = 2806V Please have the good sense to buy life insurance and be sure to create a video for others to learn from.

this is a cheap audio breaker and represents a fire hazard. Is it inline/redundant with another breaker right above it?

If you are not using a BMS, then YOU are the BMS. You are responsible for monitoring the individual cells which will likely not the be same as you get over 13.4v. And, when at the higher state of charge, it can VERY quickly get out of balance and have a cell race over 4v in just a couple of...

10000W / 30 panels = 333W panels 333W / 43V = 7.75A Each 430V string should be 7.75A Voltage drop is only 2.57% (acceptable) with 10AWG...

Making hydrogen is not that far off.

If you have the space, adding 40% more panels is far far cheaper and simpler.

There are a couple we (unfortunately) need to add: LiFePo4 - Lithium Iron Polonium(IV). LifePO4 - Phosphate.* * Too picky?

Sure, you may want to blur out your name and address, otherwise some psycho here may sneak over there and install it while you're away... Feel free to add any situational info too. What are your goals for the system? Presumably they designed the system for YOUR goals.

I just like to understand what people are trying to say. But some folks don't know what they saying, and some don't care if they are understood. And it's hard to tell which is which.

You were smart to marry a younger woman!

Maybe like this?

Sorry i only know the hard way in order to show the math... 56.5v x 16a = 904w 904w / 64 cells = 14w/cell (14w/cell) / 3.53v = 3.96a/cell (at 3.54v) Talking about amps without a voltage makes the discussion vague.

Why is your battery type set to LiPo (lithium polymer)? LiFePO4 is abbreviated "LiFe"

The manual shows 11.0v to 12.8v ??? 11.5v default Bulk charge voltage! Its going to charge to here every time! This is where you set your max charge voltage NOT in a BMS. Try setting this to something like 13.8v and see how it goes. On a different note, i like float below where my cells...

His conclusion (and mine too), is not that the "pack Ah capacity" changes at different charge levels. His point is that with a lower A (amp not amp hour) charge rate, the cells will absorb more during the bulk stage (and need a shorter absorb stage). ** the slower you pour a beer (presumably...

You might find a LOT of dust bunnies "insulating" the cooling coils. Toothbrush on a stick and then an air blast works wonders (goggles and mask recommended).

And is that a straw in your Stella? The internet never forgets. Just sayin...

Somebody does not know what a BMS does.

You will understand what you are asking about better if you know the terms you are using. You mention a 5kW system, presumably 5kW of solar panels, capable producing power at a 5kW (5000W) rate. Your batteries should be expressed as capacities, kilowatt hours. As in 15kWh. The relationship...

If you're trying to say something positive about something, you should NEVER say this.

You REALLY should put the positive and negative leads on different ends of the parallel battery bank to get balanced charging.

This is dangerous if the array is energized. >Control Capacity: 0-250V AC, 1000W My thought would be to figure out what is up with your SCC. Electronics "getting stuck at 62 volts" seems mighty odd.

I'd check with your friends and relatives to see if any have an old iPhone with a dead battery or other problem. You don't need cell service/plan, just need wifi to download an app, once. You don't need a good battery if you have power near your SCC. There are millions of old phones looking...

The voltage and current (aka watts) are a better indicator. Without a load, a panel can reach Voc without much light.

. Put them in a nice Amazon box and leave it on your front porch.

You should do an energy audit to get your head around how much energy you need: Energy Audit.

If you provide the panels specs (Vmp and Imp) for the 4x 400W panels and the 290W panel, its likely we can determine the optimal way to wire your array. I'm pretty sure your 2P2S in parallel with a single panel is very sub-optimal. Theoretically, these 5 panels would likely produce: ((2 x Imp...

I am in the camp of firm constraint rather than actual compression. So my thought is that its ok except for the ends where they could bulge very easily. If you can put something like 7/16 plywood or better, on the ends, you'd be just fine.

What is your battery voltage? if 25.6V then 7100W / 25.6V = 277A if 51.2V then 7100W / 51.2V = 138A Either way, your SCC will only charge at 100A so worrying about system losses is moot. You're leaving a LOT of power out there by not having enough SCC. What you could do would be to point...

You have to stop thinking 12V and 24V panels. Those are marketing terms from when SCCs were PWM tech. Now with MPPT, the SCC accepts voltage a lot higher, as specified by max input voltage and sometimes an MPPT optimized range. To get the maximum amount on the roof, I'd first try to get the...

I guess one would need a similarly EMP hardened refrigerator. I was going to say "and phone" but all telecom equip will be fried along with everybody else's phone. Just musing.

On a similar note, folks who camp in the sun use Aluminet (reflective netting) to greatly reduce heat in tents, RV's and under canopies. I have a 14' x 40' piece that i drape over my Sprinter Winnebago and it makes all the difference in the world for my solar swamp cooler to be effective...

I watched a couple videos and there was scant info on the batteries. I saw a mall cluster of what looked like LTO cells but I could not see or hear anything about them. In my experience, and its only been a bit over 600 charge cycles with big LiFePO4 batteries, is that MY cells will behave...

The SCC pulls the amps. Its like my 2W nightlight that pulls (2W / 120V = .0166A). This nightlight is plugged into a 15A receptacle (which is part of a 200A household), which is connected to an "even bigger" grid.

You should have asked him if it wastes all the excess power from the grid by burning that off as heat too.

This charger will limit your charging to 10A so its never going to be able to use more than your charge voltage at 10A (14.2V x 10A = 142W). You maybe better off getting a second Victron, perhaps a 75/15 for your 200W panel and run 2 independent charging systems to your battery.

Wait a minute. Lets get the facts straight, i see folks talking about 2 different situations. The OP says "completely off grid and don't use grid power" in the title. People are talking about grid tied systems, which to me, is quite the opposite. And, if the OP is "completely off grid and...

You NEED to be monitoring the cell voltages if you are playing the role of the BMS. If you are only watching battery voltage and it gets to 14V, the cell voltages could be 3V, 3V, 3V, 5V and your game is over, you destroyed a cell. You NEED to monitor them regularly. They may move slow until...

Sorry to not answer your question but, looking at your picture, you should put the charge leads (+ and -) on opposite ends of the parallel pack and not on the same end cell.

This sounds wrong. What are you trying to do? And, its only one charge controller per array otherwise the SCCs will slam dance as they seek optimum voltage amperage mix from the array. What is your array, proposed charge controllers and battery bank?

My guess is that you will find ways to use your new found power surplus if you go with the 280AH batteries. Have you ever had a closet that is too big? A garage/shed that is too big? If you have the room and weight leeway for bigger batteries, now is the time to put them in. Being solar rich...

And helpful? Dang!

My German comprehension is greatly improved but i still am not used to how long the words are...

Yes, Yes, No, No https://diysolarforum.com/search/449095/?q=do+i+need+a+bms&o=relevance

I had 3/4” copper laying around so gave this a try. Pinched it to rough form in a vise and then hammered flat with a large faced hammer (no ball peen dimples). Good scouring and coat of nolox for good measure. Works great for my 2P4S battery, over 2 years uninterrupted service.

Put as much solar as you reasonably can. You can never have too much.

You are the BMS. Hopefully you are attentive. You're fired as a BMS. (and as a battery builder) How many Ah are the cells/battery? Can you post a pic of your wiring? 2000W solar / 58V charging = 35A charging What charge do you have and what are your charge settings? You are far from the...

Yea, but I'm having a hard time with the electric still concept. Call me old fashioned...

If your neighbor put this kit into service himself/herself, its very possible it was setup wrong. I would gladly give Alt-E the opportunity to look it over... thats a great option to have. My friend just took possession of a new Winnebago that was equipped with an expensive LiFePO4 and solar...

Looks like you have gel type battery selected. I think the onboard profiles cannot be changed. Change to battery type "user" to create your own custom profile.

I have several Victron SCCs and shunt as well as a Schneider SW4048. Hardware is very good for both. Victron software especially connectivity, flexibility and ease of use is terrific. Schneider software is largely unusable and buggy. Product support is terrible. Easy choice for Victron.

Just out of curiosity, what exactly did you do to perform this test. I'm suspicious of Renogy but would need to know if you did a valid test before judging your situation. Off hand, knowing that you paid for 4 batteries and ended up with 7, ... <i dunno, nothing i type sounds right>

The alligator clips are limiting your charging. Replace them with ring terminals. Make sure you set voltage on your charger BEFORE connecting to the battery. You're not the first and not the last... https://diysolarforum.com/search/1349669/?q=alligator+clips&o=relevance

That might be a new record! We need a "hall of fame" location for impressive feats like this. The recent 48v wrench short was another with impressive results.

Something seems wrong with those quoted sentences. First, counting coulombs is counting coulombs, and what the source/destination is makes no difference. Secondly, "computing SOC with LFP..." this sounds like its based on voltage instead of coulomb counting... the non-counting meters have only...

I've been working with Frank. He hints that its a hobby system for his cabin. He started out with a modest 40A SCC, quickly out paneled that and now he has over paneled a 60A SCC. He has 4x 110Ah AGM batteries. He is charging at 50A+ and has added fans to keep it cool but it still is at the...

Property 5 miles from a power line is already off grid. No work necessary!

What is the Voc of your panels and max input volts of your SCC? If volts are too high from 4 in series, it could kill or shut down your SCC. Wiring in 2S2P would likely be a solution to manage (lower) your array voltage.

I've been here, often with 2 or 3 extra cells. As much as i felt it is a waste, when the time comes that you have a flaky cell and have a matched replacement on hand, it makes it worth while.

Its not the size of the bolt but rather the amount of contact area that matters. The bolt conducts a negligible amount of current. A smaller bolt hole actually allow for more surface area.

Have you seen the wedding ring electrical injury threads? They are gruesome. A good example of what not to wear.

In case it isn't clear, you (almost never) need to have cell signal to USE these apps, just be with bluetooth range (<25'). Just download the apps where you have a strong cell signal or wifi. No cell service required either. If you know someone with an old phone they no longer use, maybe...

Mrs Sandals is not a slave to measuring before cutting as well.

Compared to the worst mistakes we've seen here, your mistake barely moves the needle!

Someone here (forgot who, sorry) has been known to quip: “Batteries don’t die, they are murdered.”

Looking at the different pics, it looks like 2 separate 5P battery banks going into the "combiner box" above the batteries. Additionally, it looks like the center battery of each 5P bank is what is connected to the combiner box. So these "center" batteries would be getting LOTS of current.

FIFY amps is a rate amp-hours is a quantity based on a rate for a time period Using 20 amps for 2 hours is 40 amp hours. Using 20 amps for 5 hours is 100 amp hours. A 200 amp hour battery can provide 20 amps for 10 hours. A 200 amp hour battery can provide 40 amps for 5 hours. Just trying to...

Gold and silver are better conductors and would make the highest quality bus bars if that is what you mean by “best”.

Its easy to test the wiring of your balance leads before connecting. Test pin #1 (negative) against each of the other pins. They should increment in voltage by roughly 3.2v (this voltage is the accumulative voltage of cells as you approach the last pin which should be the total battery...

I see the biggest opportunity for value-add would be to offer a compatible BMS that has good software for configuration and monitoring. Take a look at the Victron apps - amazing stuff. To me this differentiates them from the field enough to overlook quite a bit of cost difference.

Holy crap, quite a few zeros! Thanks. Like the other day, my wife knew i was on a specific highway and she called to warn me about a wrong way driver. I said: "One? There are hundreds!"