diy solar

diy solar

Last fire.. :-(

You are correct.

The main DC breaker is not going anywhere, stuck between 4* 35mm2 copper wires, short who are mounted on the bus-bar that also aren't going anywhere as being massive copper.

I can hang on it, if I want to, and it won't get lose.

Its worth pointing out that the short circuit current rating is only valid if the breaker/protection device is mounted as per the manufacturer's specifications (UL489). Most of the time din rail is adequate but some breakers require a mounting plate. The point I'm making is to be aware that without proper mounting and a condition happens where the breaker needs to instantaneously trip, the wires holding the breaker may not be sufficient. Worst case is the breaker becomes loose during a fault, or the breaker fails to operate as its intended.

You seem content with your installation and thats fine. For anyone playing at home should consider otherwise.
 
You seem content with your installation and thats fine. For anyone playing at home should consider otherwise.
I'm content, satisfied with this amazing high safety installation that without joking is most likely to be the safest installation in 20 miles radius.

And no, I'm not that far out :)

I'm absolutely not telling anyone to make an installation like this.
As it is not safe according to USA or European standards.

Where the average safety is 2 wires twisted, shielded with a plastic bag and some wire against the rain.
That is here the normal installation.

I got in a huge fight with my brother in law, mixing up the 3 colours of cable at each junction point.

His answer: oh, but you feel m when you have the power wire.
And if you use the wrong other one (aka grounding, yellow/green for us), it does not work.

Simple and basic.
And yes, sometimes the ground wire is here the life wire.
Standard normal installation for most households.

I doubt this is in your house the normal way to treat electricity.
And in Thailand most people are affraid of touching anything electric except light switch, with reason :)
I doubt this is in your country.

That works in Rural Thailand, will not work in your country.

It's not my first electrical installation.
In Netherlands I had a mining farm in a rental house.

The company liked to check my installation and the guy from professional installation company came by with big fluke test equipment suitcase and thermal camera.
Purring like a kitten.
If all DIY installation was as good as this.....
Even professional builds usually had more noise.

Fire department came to check as well, also impressed by the installation.

It's not that I don't know what or how to install, most things simply aren't here.

Things like in-house cable, the gray one, about 15mm thick, 3* 2.5mm solid core wire....

I really would have liked to use that here also.

Unobtainable.

Din rail...
Post order form China, takes 10 weeks to arrive.

Or actually most parts take 10 weeks to arrive.
Any single part you like to use.

I'm not professional installer and I can't order all the parts needed before installing.
Like most
If it's not obtainable, and you need to wait a long time, and without you are sitting in the dark...
You will use obtainable, things available.
By all means, not perfect, but works.

With unlimited funds, I'll build a separate building for the electricity, with its own cooling system.
New setup, Victron equipment, nice cable rails etc. All nice and sweet.

Then after a year or so, when that is finished (parts take its time)
I'll power it up, switch over to the new setup and rebuild during one or Two years this setup as backup.

Not because I don't have the time, bit it takes ages to get something.

If you aren't depending on what you are using, it's easy to point and say
"do different".
You are invited to do so.
Remember, all the things you don't bring with you, probably aren't available locally.
You probably will need to extend your visa a few times, waiting for the parts to arrive.

Then, and only then are you capable of bashing my installation.

While far from perfect, is amazing compared to normal local standard.

And...
30-40 years from now, your "perfect" installation will no longer be conciddered safe.

Perhaps hard for you to imagine..
Buffalo and cart to transport wood to make charcoal in a clay oven is here normal.
Cooking on charcoal is.
I don't know when the people in the states stoped doing this.
30-40 years ago? Longer?

So if you want to compare with anything, do it with electrical installation of the 70's and 80's rural area, say Alaska?
While New York will have all the Goodies you like... That doesn't help you out there.

That doesn't make the installation in my home or rural Alaska ? your perfect installation.
Absolutely not.

Rules and regulations...
And real life.
While a rule and regulation might require a special fire delaying board to mount the dinrail, the breaker will work just as fine with as without it.
It doesn't need to "push off" on something :)
Or hold on to something.
Yes, there will be some forces, nothing crazy.
Unless you test it 10.000 times, then one might fail after 9.000 trips.
Just saying...
There is common sense, like knowing you can't put your stereo in 10 and expect the speakers to last year's. That's all according to regulation, not a problem.

Or feeling the need to mout 16A breaker on a fire delayed box as it might go wrong.

Speaker will go wrong, allmost all the time.
Breakers almost never will go wrong.

You should not break the speed limit.
Even in Germany where it is allowed to drive 180 miles per hour, you should stick to the 60 miles USA thinks is safe.
I don't know who have more deaths in traffic due speeding per million...
I doubt any will match the Thai death toll....
I guess this is a country for those who live dangerous :)
 
Sorry i did not read all the pages, but damn, lucky nobody hurt...big F sake..lifepo is a pretty save chemical...what if it was li ion...
Anyway i think those cells where good, but the bms was not...
I still think the best bms is from batrium, and not the chinesium bmsses, sorry.
We all know what the min and max limit is of those cells regarding voltage, and we all know that the Chinese bms are not so perfect to maintain those borders.....
 
and we all know that the Chinese bms are not so perfect to maintain those borders

Well, I don't really agree with that. I've had very good results with a Chinese BMS (running over a year now) - where it performs much better than expected. Chinese manufacturers have been playing catch-up and they're gaining fast. It probably helps that the battery industry in China is huge and most Lithium batteries originate there.
 
I'm content, satisfied with this amazing high safety installation that without joking is most likely to be the safest installation in 20 miles radius.

And no, I'm not that far out :)

I'm absolutely not telling anyone to make an installation like this.
As it is not safe according to USA or European standards.

Where the average safety is 2 wires twisted, shielded with a plastic bag and some wire against the rain.
That is here the normal installation.

I got in a huge fight with my brother in law, mixing up the 3 colours of cable at each junction point.

His answer: oh, but you feel m when you have the power wire.
And if you use the wrong other one (aka grounding, yellow/green for us), it does not work.

Simple and basic.
And yes, sometimes the ground wire is here the life wire.
Standard normal installation for most households.

I doubt this is in your house the normal way to treat electricity.
And in Thailand most people are affraid of touching anything electric except light switch, with reason :)
I doubt this is in your country.

That works in Rural Thailand, will not work in your country.

It's not my first electrical installation.
In Netherlands I had a mining farm in a rental house.

The company liked to check my installation and the guy from professional installation company came by with big fluke test equipment suitcase and thermal camera.
Purring like a kitten.
If all DIY installation was as good as this.....
Even professional builds usually had more noise.

Fire department came to check as well, also impressed by the installation.

It's not that I don't know what or how to install, most things simply aren't here.

Things like in-house cable, the gray one, about 15mm thick, 3* 2.5mm solid core wire....

I really would have liked to use that here also.

Unobtainable.

Din rail...
Post order form China, takes 10 weeks to arrive.

Or actually most parts take 10 weeks to arrive.
Any single part you like to use.

I'm not professional installer and I can't order all the parts needed before installing.
Like most
If it's not obtainable, and you need to wait a long time, and without you are sitting in the dark...
You will use obtainable, things available.
By all means, not perfect, but works.

With unlimited funds, I'll build a separate building for the electricity, with its own cooling system.
New setup, Victron equipment, nice cable rails etc. All nice and sweet.

Then after a year or so, when that is finished (parts take its time)
I'll power it up, switch over to the new setup and rebuild during one or Two years this setup as backup.

Not because I don't have the time, bit it takes ages to get something.

If you aren't depending on what you are using, it's easy to point and say
"do different".
You are invited to do so.
Remember, all the things you don't bring with you, probably aren't available locally.
You probably will need to extend your visa a few times, waiting for the parts to arrive.

Then, and only then are you capable of bashing my installation.

While far from perfect, is amazing compared to normal local standard.

And...
30-40 years from now, your "perfect" installation will no longer be conciddered safe.

Perhaps hard for you to imagine..
Buffalo and cart to transport wood to make charcoal in a clay oven is here normal.
Cooking on charcoal is.
I don't know when the people in the states stoped doing this.
30-40 years ago? Longer?

So if you want to compare with anything, do it with electrical installation of the 70's and 80's rural area, say Alaska?
While New York will have all the Goodies you like... That doesn't help you out there.

That doesn't make the installation in my home or rural Alaska ? your perfect installation.
Absolutely not.

Rules and regulations...
And real life.
While a rule and regulation might require a special fire delaying board to mount the dinrail, the breaker will work just as fine with as without it.
It doesn't need to "push off" on something :)
Or hold on to something.
Yes, there will be some forces, nothing crazy.
Unless you test it 10.000 times, then one might fail after 9.000 trips.
Just saying...
There is common sense, like knowing you can't put your stereo in 10 and expect the speakers to last year's. That's all according to regulation, not a problem.

Or feeling the need to mout 16A breaker on a fire delayed box as it might go wrong.

Speaker will go wrong, allmost all the time.
Breakers almost never will go wrong.

You should not break the speed limit.
Even in Germany where it is allowed to drive 180 miles per hour, you should stick to the 60 miles USA thinks is safe.
I don't know who have more deaths in traffic due speeding per million...
I doubt any will match the Thai death toll....
I guess this is a country for those who live dangerous :)
I appreciate your sincerity - and your determination. Glad you and your family are safe. The difficulty comes when people with less skill and knowledge take unnecessary shortcuts - we can all be guilty of that.
 
Ok I'll admit I haven't waded through every post, but something I don't "think" has been mentioned is over compression. Especially on cells that are already over filled in the case ie 152ah in a 120ah can. There's gotta be a reason the only data sheet I've seen that recommends compression says 12psi max. To much compression probably leads to internal cell damage.
 
Ok I'll admit I haven't waded through every post, but something I don't "think" has been mentioned is over compression. Especially on cells that are already over filled in the case ie 152ah in a 120ah can. There's gotta be a reason the only data sheet I've seen that recommends compression says 12psi max. To much compression probably leads to internal cell damage.
Not explicitly mentioned, over compression.

As there was no compression at the start, and they started to bloat spontanious (no over charge, over discharge or too high current) when it was clear they needed compression from the start, it was too late.

If they would be 25 bucks total, I probably would have tossed them out and bought new.
Few zeros extra and plus some..
For me way to much to just kiss goodbye.
Especially as no abuse had taken place (except due "wrong" manufacturing, pushing the limits)

After they (slightly) bloated, compression took place.
Not a lot, hand tight with pipe wrench. 15* 1/4 inch.
Enough to clamp a cell string enough I could no longer lift it out by holding both terminals with my hands.
(No bus-bar yet, just the cells)

What I did notice is that after time, they "de bloated" and cells got more free space.
I could lift one
(again, no bus-bar just cell)
6 in a row.
I tightened a bit further till I could not lift again.
That happened a few times.
Not sure how many or how much less mm bloating on the 6 cells.
I guess 2-3 mm at a time

This tighting again and again probably is over compression.
Not by force at once!
But the de-bloating was not good for the cells.
And with it, a slight compression probably was enough to make failure.

Most cells don't bloat.
My 280's didn't bloat, yet where treated the same way.

Start of the bloating problem is with the 152Ah cells, and my lack of knowledge that they need to be compressed at start.
Probably as we know now with non conductive sheets between each cell.

After this, a cascade of smaller errors, unintended and/or unforeseen.
Eventually...
Fire.

If you make one time installation, your BMS does not fail, you use grubscrew, Loctite red+ primer, and compress the cells, the 152Ah are safe to use.
For ease of handling, 24v S8 sets, each with own BMS.
(Yes, you can stack 2 BMS S8 to make S16, not the best way, also not unsafe)
Each set own BMS S8 would required for me 6 BMS for 48 cells.

I tried to use just one BMS...
(In the beginning)

Micro errors...
Fault?
Failure, yes. Due unforseen.

Most people today advice (I'm not different) to use compression.
Compression by factory specifications, or just a tight fit.
You don't need to crush the cells!!
Snug fit is good enough, when it can't move (lift out), it's good enough.

That's what I did...
Yet...
Wrong starting point.
Already bloated.
Wrong usage, the screws provided by the seller. (2 mm too long, solved with washers, not ideal)

And as most of us are:
Beginner in this field.
 
from what I've personally seen pretty much all lifepo4 cells plump a little at full charge. In a typical cell not always enough to puff the outer case-probably because they have a little room to grow inside. So 152ah jelly roll in a 120ah case would be a lot more noticeable w/o necessarily meaning they where actually "swelling" more than normal.

my background is more mechanical than electrical professionally. So I am more familiar with things like compressive force. I torque a lot of pipe flanges, so I know what torques give me a proper crush on a gasket( usually 4-5000 psi. I hate having to torque rubber gasket flanges because rubber usually cannot be crushed over 1000 psi w/o disentigrating - and that makes getting a good bolt stretch (necessary to keep the bolt from loosening) almost impossible... anyway all that to say this-

a grade 5, 1/4x20 bolt/ allthread @ dry 8 ftlbs torque (proper torque for this hardware) has a compressive force of 2025 lbs. so assuming a standard 120ah cell is aprox 7"x7" thats a 49sq inch area to be compressed. assuming 4 points of compression on the cell (going from memory of the pics I saw earlier- i know my numbers will all be estimates) so thats 8100lbs of compressive force on a 49 sq inch area- or over 165psi or over 13 times the maximum compression recommended for lifepo4 prismatics.

Everyone has jumped on this compression bandwagon, but I have seen very few posts about maintaining the proper psi. It's very little- almost none- never enough to keep a nut even tight on allthread- which is probably why I have NEVER seen a professional pack that used anything more than tape to hold compression. 8ft/lbs is nothing. BUT it achieves 13X MORE compression than MAX compression on these cells.

Want proper compression, my personal advice, discharge your pack-put a rigid board on each end- wrap the pack in fiberglass reinforced tape. the slight swell at full charge will probably be all you need. In short these cells where crushed.
 
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If I remember correctly we did some calculations in a thread here some time ago that, depending on the amount of rods used, it's something along the lines of 4 to 5 Nm torque per bolt to get the compression per the datasheet for a 280Ah cell.
 
If I remember correctly we did some calculations in a thread here some time ago that, depending on the amount of rods used, it's something along the lines of 4 to 5 Nm torque per bolt to get the compression per the datasheet for a 280Ah cell.
this will be HIGHLY dependent on bolt grade size material and lubrication. for instance ever the spec I listed are for dry bolt and nut-add lubrication and it goes from 8ftlbs to 4 with the same grade hardware.
 
Lol.

Some see a mess where others see art :)

I know it's your job to criticise.
And sure, with unlimited funds and access to products, I could do it all again, a lot more nice.

You clearly don't live in Thailand, and absolutely not in a rural area.

If it's normal to have one shop sell stainless M6 nuts but not bolts, and the other shop might just have the bolts.. not the 50 you need, but 10.
Other shop has also.. too short, or way too long.
This is just M6 nuts and bolt.

In a country where safe is 2 wires twisted for lights in a gouvernement building, you will have a few years struggle to find the equipment you like to use.

Probably even end up buying a lot of it overseas.
Where transport and tax for a $10 tube of glue is $160,- (no joke, Amazon) you will need endless funds and time to make the installation as nice as you like.

Art.
It's amazing it's this neat and safe to build in rural Thailand.

Don't think it's here any better then the middle of Africa..
Your nice tools and stuff... Just isn't here.

You are welcome to ship it to me.
And I will install it.
As you like.

Alternative?
No electricity.

You know how that is?
A few people in Texas now have experience, for a really short time.
For us, 24/7, always.

Easy to bash when you have all tools and equipment available.

This is the best available.
And I didn't went cheap, at all.

Like the Dutch say: you can't brake iron with your bare hands, or for you English people, can't bent space and time.

I see art and am absolutely happy with the highest quality result capable with the limit equipment.
For the record I do live in Thailand, I am rural, do not have grid power, facing the same challenges that you encounter when looking for hardware, but manage to overcome them.

There were so many critical mistakes made that it's not supprising you've had multiple failures and most likely will have more. There is a pattern of denial which makes it impossible to reason with you, the repetitive rambling about how perfect your installation was in comparison to others isn't going to help the situation.
 
I planned to be done with this thread .... and don't really want to pile on ..... but, one thing that caught my eye was .... hand tight with a pipe wrench.
 
this will be HIGHLY dependent on bolt grade size material and lubrication. for instance ever the spec I listed are for dry bolt and nut-add lubrication and it goes from 8ftlbs to 4 with the same grade hardware.

About 2:1 range of force for the same torque.
And then the issue of radial force and tilt of the nut adding friction, so I suggested a socket extension.

We also discussed springs which many people used, and @HaldorEE used a load cell to measure Belville washers for use as springs. Measuring displacement you can get well defined force, and maintain it in a range over a range of expansion.

I also suggested stacking LiFePO4 on its side and recycling your old lead-acid bank as weights to make compressive force. :)
But I'll withdraw that now that Will learned for us that cells on their side may leak.
 
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We also discussed springs (I may have been the first to propose it here), and @HRKD used a load cell to measure them. Measuring displacement you can get well defined force, and maintain it in a range over a range of expansion.

Nope, wasn't me that did any load testing. At least not that I recall. I've had some genius moments that I don't recall.
oldgit.gif
 
About 2:1 range of force for the same torque.
And then the issue of radial force and tilt of the nut adding friction, so I suggested a socket extension.

We also discussed springs (I may have been the first to propose it here), and @HRKD used a load cell to measure them. Measuring displacement you can get well defined force, and maintain it in a range over a range of expansion.

I also suggested stacking LiFePO4 on its side and recycling your old lead-acid bank as weights to make compressive force. :)
But I'll withdraw that now that Will learned for us that cells on their side may leak.
It was HaldorEE .... he experimented and did his compression using Belleville washers. There's a picture of his test gauge here. https://diysolarforum.com/threads/b...busbars-on-cells-terminals.16952/#post-208058

oops .... didn't hit the right post ... it was #20
 
It was HaldorEE .... he experimented and did his compression using Belleville washers. There's a picture of his test gauge here. https://diysolarforum.com/threads/b...busbars-on-cells-terminals.16952/#post-208058

oops .... didn't hit the right post ... it was #20
With springs, it would seem that besides the benefit of maintaining a more even pressure of a range of SOC swelling, you also have a direct measure of the compression by measuring the compressed height of the spring.

Load cells are even better (if you have them ), but I suspect that measuring compressed height is good enough (I'm seeing springs in the range of 100-200 lbs per inch spring constant). This then alleviates the need to measure the torque on all threads or consider nut/bolt size/rating variabilities. You just need to measure the spring deflection at max SOC and keep it below 18 psi.
 
Have you seen this thread?

 
Have you seen this thread?

I waded through part of it; it is long, however did not see any discussion of using spring compression to measure force but rather how much threaded rod size affects the torque required.
 
Fire distinguisher does 2 things.
The green one for electrical fires.
(Halon is most known name)

1 remove the oxigen
2 cool down a lot!
Like submerge it in (almost) liquid nitrogen..
That's extreme.. not that cool.
But you get the idea.

If it's enough to stop new cells from selfdischarge, that's already a win.

Yeah, my understanding also.
If the battery starts to go, not much on stopping it.

There is liquid used for submerge computers
It would reduce the issues to one cell.
Price for that setup is probably double from the purchase price :)

Water 100% will work also, except as soon as one cell burst, it's no longer 100% H2O and will conduct electricity, what will make the whole set blow up.

Making it safe, and prepare for the fire that might (will) happen is the only really good advice.

If fire / heat source can't get food, it will die.
Just our task to limit the damage during burning phase (with or without flames) and let it die safely.
This can take days!
With just 15% SOC it's already 36 hours and still hot.
I guess I got lucky there

View attachment 57443

Even if we would not have been home, this baby would have stoped the fire, killed most heat.

But before it goes, 68c...
My Inverters would have been smoked also ?

Edit:
We now have two small ones, work faster then sand, and for starting fire.. large enough.
View attachment 57447

If things really go out of hand....
I guess I can make a 1500L watertank release..

It will prevent the house to burn down, but a LOT of damage.
As last resort ??
Will you please provide a source for the fire suppression equipment in your photos?

thans in advance

Ed
 
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