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lets do some math!! first, for wind pressure loading we will use the simple cheat formular of around: pounds/sqft = 0.00256*(mph*mph) so 90mph wind results in a force of 21lbs/sqft (its double for a cat5 hurricane hehe). For a 4'x8' solar panel you have 32sqft * 21 = 672lbs force per panel. you...

so I have some aliexpress express cells and of course even after top balancing they quickly like to get out of balance... neither the daly or overkill solar BMS in "balance" mode does anything useful. with cells out of balance by about 130mv I let the bms do its balance thing for a few days...

those are the same guys that tell you to pay to put nitrogen in your tires.... Did they sell you a "solar panel energy draining device" to avoid explosions when not in use?

thats because, at least in america, the is a massive decline in what is called "critical thinking skills"... basically, its not that people are stupid (which means they cannot think) its that they are being "taught" to be ignorant; because ignorant people do what they are told. sadly the jury...

The events are real...but what you REALLY want to know is: A) is it a government next generation weapon system B) not from this planet and for that nobody knows so far; unidentifed does not mean (que spooky music)

given the danger of high current DC circuits, you definitely need the more expensive Class T fuses; anl fuses or others would just plasma arc and happily conduct all the current available, but it would be easy to find the spot where it failed!

well, modern humans have been living off "meat" and preserving things with salt for about 200,000 years; so its probably not that big of a deal ;-) my recent ancestors (3 generators back at least) lived off salt as a preservative, eggs and bacon every day, pork fat and alchohol into their late...

well, only an old retired engineer here, so I will take a shot at making it "simple" ;) (said absolutely every engineer as they start their presentation) An amp is just a coulomb/sec or 1coulomb = 1amp * 1sec. the rate of flow of the electron does not give a hoot about the...

HAHAHAHAHA.. not a SINGLE democratically run city in america has a budget that is not massively in debt with out of control crime and failing businesses; chicago, new york, los angeles, san jose (ok lots in california,, why do you people keep voting for them??) For the past 5yrs the democrats...

here ya go....extremely efficient, pet approved ;-)

perhaps some confusion, I did not mean you use these in place of a BMS or as part of your initial cell top balance. This is for the "normal" day-to-day imbalances that will happen; relying on the BMS that says it can balance has, at least for me with both a smart daly and an overkill bms, shown...

yes, global devastating climate change is most certainly "political" and not actual science... climate always changes, however, you can easily go back over the past 60years and see that people in charge always declare some "soon to be" disaster approaching that we need to spend money...

this is the fundamental issue that caught me and others... he ASSURED everyone that the money was in separate accounts and safe until product shipped...he absolutely, positively lied about this. This is not an issue of "got taken by surprise in world events of shipping/supply issues"...nope.. He...

it is real easy to find the cheapest batteries on the market...however... you want to actually get the lowest $/kwh which is wayyyyyy different than finding the cheapest battery hehe

step one...move to another state ; NOT california ;-)

UPDATE... I managed to get even aliexpress to agree that I cannot upload a 12hr video with a 500mb limit, so they agreed to allow me to upload the video to online storage site and send them the link... so I uploaded the looooong video which was compressed down to 2GB and finally aliexpress did...

sadly there is some truth to this if you buy the lower end flukes...hence the need to get a voltage reference. That said, Even the cheaper units will meet their specifications so you have to read the fine print hehe. for example here is the spec for fluke 117: DC volts: +/-0.5% + 2counts and for...

your question was can BAD cells hurt good cells... its in the title; the answer is no; the BMS stops that from happening. if you have a different question, perhaps you want to word it in a different way and, well, do keep in mind there are no "paid" contributors here so everyone is helping you...

order enough eve 280Ah cells for another 24v pack from @Amy Zheng and the packaging was fantastic!!! They did not try to overpack a box with a bunch of cells and see how much tossing they can withstand; just 2 cells per box, very well packaged in perfect fit foam shells; boxes nicely taped up...

"raise your hand if you looked at your first batch of cells and thought the BLACK terminal would be the negative one so you starting wiring" <<raises hand>>

I plug and unplug mine without a care in the world...no damage at all, and they are just the cheap $30-$40 ones. for my BMS cables I always make them as a "Y" cable so the BMS always stays attached and I can swap in a balancer or a isdt batgo to look at things directly (the isdt units have a...

well, this is the chit chat forum and I did ponder a while if I should respond as this is a touchy topic for many people due to, well, what is really happening in the world that most are unaware of hehe So here are a few thoughts/comments... social algorithms are not conscious "things" that...

I did a long winded post on this topic some time back... https://diysolarforum.com/threads/inverter-capacitor-pre-charging.23340/post-275233

thats the trap you can fall into, thinking that with a 3.6v per cell total charge voltage you cannot reach a cell overvoltage condition... Definitely not true, which is why a bms is needed for any series build. When, not if, the cells become slightly unbalanced one cell can certainly reach a...

looking at your setup pictures, do you have a negative battery connection that is going "around" your shunt? hard to tell but it looks like two wires are there. Nothing should be connected to the negative terminal of the battery but the shunt, this makes the shunt measurements the golden...

wiring "rules" definitely vary by country. This is mostly about north american electrical house wiring to "some" code (do keep in mind that the electrical code has changed and so a 40yr old house is not wired the same as a 2yr old house). filterguy has given you lots of good information...

I think the "coolest" batteries coming out are... liquid metal batteries such as those by ambri. A battery you can push hard, has massive cycle count, does not care about environmental temps, insanely safe...and its a "cool" idea hehe ok, its not going to fit in your cell phone or even your...

so you are concerned about the "government" not being able to figure out how to get more of your money??? have no fear at all, they WILL figure it out. Once the government got together and gave itself the power to tax at will, the government has never had any shortage of innovative ideas about...

old will prowse video

the sun could go nova and the media/democrats would blame trump.....

I ordered eight of the 280AH cells..it did not go well. https://diysolarforum.com/threads/fyi-warning-about-liitokala-varicore-flagship-store-aliexpress-do-not-buy.21252/page-2#post-256932 good luck , it may turn out ok; make sure to capacity test each cell AND if you try and get any money back...

The BMS is protecting your individual cells as other have pointed out. You can try and go the DIY route by getting a very low capacity smart bms that will provide you all the data from the individual cells, and then add in an arduino to extract that data from the smart BMS, aannnddd then add in...

sorry, hit return without giving any steps to check..oops... ok, back to debugging the first issue: 1) make sure you check battery voltage at the battery terminals no load, then measure at the inverter battery input UNDER LOAD... 2) with zero solar your inverter/battery should run a 600w'ish...

extra solar...hehe... people always have very different setups and it certainly shapes they view point. for example, I have a small place and consume about 50Kwh/day...so the first thing I thought reading the above was "Wow, that guy much have a huuuuggge solar panel farm to have extra power"

test the cells either in series or individually and whatever is the lowest capacity cell...thats the ampacity of the entire pack. as you know these are likely to be very mismatched, you should get an "active" balancer, the builtin balancers for almost every BMS seems to be designed around the...

putting in a backup power system in a commercial building is very expensive... The number of "regulations and rules" that also apply is, well, quite impressive..sigh...

I use these https://www.ebay.com/itm/313221927381 (the run around $35-$40) the hardware version is V1.3 so watch for that..I have been testing the V1.3; I did try a V1.1 and it was useless...

here is my panel with the button/resistor in a little box that go around the cutoff/disconnect switch.

valid point so the easy answer is...everybody use a 400W 2ohm resistor and count to 60 hehe naaaa....lets try some math to see what we get! This should not be this hard hehe we should have a simpler way to help answer this recurring question. You are trying to limit the inrush current without...

it is not technically hard at all, that is not the issue. At least in the US it about the massive regulatory costs to do such a thing, it just makes zero business sense. I simple $500 generator could easily run the pumps at a service station, the cost to install such a thing could easily run in...

no, that is not correct... amp ratings are based on power "lost" to heat; its just I^2 * R, and you can calculate that by the resistivity of various materials. The more heat you generate, the higher the resistance of the material gets, its not about "withstanding" heat. electrical wiring codes...

if you want to focus on NEC code, well, thats an entirely different critter; better pay to get a permit from your local government and hire an electrician, may need to have a "solar specialist" do a site survey and sign off on your plans before you can put in USB outlet. yes, I am bit touchy...

so you have four "8 cell" battery packs each with their own BMS...attached to common busbars...nothing wrong with that. So your concern is "The four fortune batteries do not charge equally nor discharge equally?" A few thoughts are: 1) did you top balance all cells prior to building each pack...

why oh why have schools stopped teaching math, sigh... its a simple math problem for most of these ideas to show the "real" energy available is not a fraction of what the marketing people say it is. Then there is the flip side where math shows there is enough energy, but the environmental...

foam can, if, and this is the really important part...it is an engineered product that is designed to stay in its elastic state under the designed load without transitioning into its plastic state(where it deforms and does not recover). It is interesting that poron evextend 4701-43 is designed...

as you have a "conductive enclosure" consider using something like PVC show pan liner between your batteries and the aluminum. The material is readily available, durable, and cheap ;-) and yes...you should always place plastic tubing over your threaded rods to avoid "oopsies"...

use some of the internet planning sites to get an early idea of the load you are designing to, such as: https://unboundsolar.com/solar-information/offgrid-calculator The tricky part is not only WHAT the device load will be, but how often that load will be running per day. the you can convert...

sigh... https://interestingengineering.com/solar-roadways-engineering-failure https://redgreenandblue.org/2020/06/15/solar-roadways-fail-despite-big-investments/ https://www.sciencealert.com/the-world-s-first-solar-road-has-turned-out-to-be-a-disappointing-failure...

well thats makes sense of course... what happens if that cooker starts to leave without permission!!! Oh for the days of "simple" software that just did what, and only what, it was suppose to do. I guess I should be happy it did not demand a facebook account or something. (and yes, I did have...

fair enough, lets think on each part of that. safety concerns: this entire forum is definitely about people handling dangerous amounts of power. If you want to be safe you would hire an electrician/licensed subcontractor and have the entire thing done..for an insane amount of money (well...

I purchased one from overkill to help support them and their "value added" model. Adding on custom interface options with support, I think thats worth the extra. If you want the absolute rock bottom price, that will always have some risks with it (I have been bitten by that bug a few times...

when it comes to batteries of the same chemistry, when you put them in PARALLEL you will get the sum of their AH ratings NOT the sum of the output current. for example: 2Ah battery in parallel with a 1AH battery will provide 3AH of "power" as they will both be at the same voltage (they are in...

a few comments: 1) do not deploy a 12v based system, go for at least a 24V battery bank given the large loads you may want to put on it 2) when it comes to motors you want what is called a soft-start option..you can buy soft-start conditioners but they are expensive 3) do not plan on running...

here ya go, to help you I will start you on your journey of discovery... how about a deaths per terawatt of power produces table below... once again, YOU could easily research this yourself as it is not that hard unlike the days from us old geezers when we had to actually TRAVEL to a library...

the very definition of "dielectric" is that it is an insulator hehe these product are to stop contact with oxygen(and water) so the wires do not degrade; and when needed its a good idea to use it. Noalox is a barrier grease, the zinc crystals help penetrate aluminum oxide(its grease with sand...

any company that has built up its business model based on quick, and cheap, shipments from china, is, well, really hurting now.

looking at the picture you have an inductive balancer instead of capacitive(maybe) so make sure to post how well it does... if you have a good multimeter check each of your cell voltages so you know exactly what is going on before you plug it in. You should be able to quickly (well, relatively...

everyone that lives on an island knows that shipping is VERY expensive...and in many cases shippers will not deliver to that address. You knew you lived on an island so the right way to give your address would have been, "I live in spain, ON AN ISLAND". You kept a very important part of your...

"specification creativity"... yep...you really do have to admire far east marketing teams that embraced this creativity. Once they realized most people do not bother to think if whats on the label is even possible...they really let the big numbers fly hehe I am thinking we will see "compact"...

you want to fuse all direct lines connected to a power source because the world is filled evil screw drivers and wrenches, that will, at the worst times...dive right between any open metal contacts and short out the source. its the tools you see, not that people sometimes are careless, nope...

well you just have to be curious as to what those cells "really" are hehe... could be a grade "A" cases with a AAA battery inside hehe

lipo packs have the highest energy density..lifepo4 has less, but safer and longer life...LTO has the least energy density but the longest life (by FAR); LTO packs are the kind of thing you install on a mountaintop where you do not want to return to for a decade or two...

that picture seems to show more "melting" (which means heat) on one side. With the fuse intact that looks more like, this is a guess, that end was either not tightened down enough or somehow became a higher resistance connection. A high resistance conneciton of just 20amps going thru it would...

I think this is obviously the issue... He saw a business opportunity using the "forums" good will he had built up to create a business. It did not start out as a business but an actual "group buy" that he thought he could evolve. Once he decided to switch to "big business" mode he started to...

I have the lv2424 and it definitely does NOT bond N/G on battery....even tho they said it does; probably varies by model and they have only a single answer they give out ;-) when it comes to bonding you have to deal with a variety of situations: 1)plugged in, on grid: LNG are all present and...

the BMS is stop any damage to individual cells, even smart chargers, unless they have a wire to each individual cell, are only monitoring the total voltage which absolutely does NOT protect your batteries unless you keep the top charge voltage very low. I agree that the high voltage cell...

Keep in mind the distance you plan on running the wires. The "heat" that is causing the danger flags is your old buddy V=I*R and Watts=i^2R. That is why the material of the cables really really really matters. The resistance increase from copper, to aluminum, to steel (or nickel) is actually...

not to worry..it has a QC sticker on it. I like the battery manufacturers that like to make the black terminal positive just to keep you on your toes hehe

make sure to measure your connector carefully... sadly the phrase "JST connector" is a family of connectors with different cases AND different pin spacing, which is real irritating. Some pins have 0.1" spacing, other have 2mm spacing; yes I found out the hard way when I ordered a bunch of...

your fuses are to protect your wiring and make sure there are no fires!! You do not just "upgrade" a fuse without also changing your wiring and connectors. I would recommend you include your wire length and guage in your drawings to make sure you have everything sized correctly.

he does that a lot, just ignore him; the ignore feature on this forum works really well...

well I did a test and carefully measure the expension of an EVE brand new cell from 50% to 100% SOC...this was NOT in a fixture, just free standing. The answer is that I measured an expansion of .762mm so that is much less than what I thought it would be however it is certainly more than...

and another contestent has now played the favorite game of many... "what happens when you buy the best of the worst BMSs"!! notice the specs on that daly you linked: BMS protect battery charge voltage: 3.75V. BMS protect battery discharge voltage: 2.2V. Continuous charging current: 50A...

thats the standard approach with aliexpress. I had the exact same thing happen on two different orders when what arrived was clearly not what was advertised. I had pictures to show the product was "false" (pure nickel strips that promptly rust), and aliexpress just says unless you ship the...

instant messaging "apps" much like twitter/facebook is just best completely avoided.