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House burned down

One thing it seems people are missing here is the batrium design - the BMS doesn't have any ability to shutdown or limit current other than the shutmon module.

In this case the shuntmon was installed after the different battery banks were brought together. Which seems to be exactly how batrium intended things to work. This means the only thing standing in the way of the different banks dumping into each other were the 7 fuses.

The image is for a 2 battery setup.

View attachment 213164


You are correct, this is how Batrium is designed to work, a fuse on each parallel set of cells is the protection which any parallel battery setup should have. Take note, both batteries in that diagram has a fuse on the positive terminal.

The OP's failure was due to the fuse type. It was the correct system design, just the wrong fuse.

Attempting to put blame on the BMS is not correct. The BMS will do exactly what it is designed to do. No current passes thru the Batrium, mosfets can't fail because there aren't any. One can run huge inverter loads with a Batrium.

Instead of spending your energy blaming the BMS, you should instead spend the energy informing members there should be a Class T fuse between any parallel batteries.
 
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You are correct, this is how Batrium is designed to work, a fuse on each parallel set of cells is the protection which any parallel battery setup should have. Take note, both batteries in that diagram has a fuse on the positive terminal.

The OP's failure was due to the fuse type. It was the correct system design, just the wrong fuse.

Attempting to put blame on the BMS is not correct. The BMS will do exactly what it is designed to do. No current passes thru the Batrium, mosfets can't fail because there aren't any. One can run huge inverter loads with a Batrium.

Instead of spending your energy blaming the BMS, you should instead spend the energy informing members there should be a Class T fuse between any parallel batteries.

I wasn't blaming the BMS, just pointing out there was no individual BMS per battery like people expect.
 
Attempting to put blame on the BMS is not correct. The BMS will do exactly what it is designed to do. No current passes thru the Batrium, mosfets can't fail because there aren't any. One can run huge inverter loads with a Batrium.
unfortunately I think that the targeted discussion toward the BMS was a fault of mine. I do appreciate the additional insights but fear those pages of misunderstanding were caused by me. Sorry!
 
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Hi all,
I'm really not asking for anything, but someone asked, so here is a link of an action my friends set up:


I wanted to "report" this fire to you all as in my opinion it is the right thing to do as it maybe can help others prevent it, and i wont say its easy.
Im typing this literally from a hospital bed. Adrenalin makes you go trough the first days, but now i know theres a rebound.

I have not read it all, but i can certaincly say when a new system is installed, it will be with the "t" fuses. Wishes i knew about them years ago.

Be safe guys.


Bump for the donate URL some asked for
 
unfortunately I think that the targeted discussion toward the BMS was a fault of mine. I do appreciate the additional insights but fear those pages of misunderstanding were caused by me. Sorry!
Thank you.
 
Hi again,
If i came out rude in one of my posts, my apoligies, it has been a rough time lately.
Indeed full metal shelves lined with hpl.
All cables were 70 mm2, length between bank and busbar aprox 1.2 m, all wires equal in length.

Thanks for the donations ❤️
 
Hi again,
If i came out rude in one of my posts, my apoligies, it has been a rough time lately.
Indeed full metal shelves lined with hpl.
All cables were 70 mm2, length between bank and busbar aprox 1.2 m, all wires equal in length.

Thanks for the donations ❤️
You have every right to be tense. All these jack offs, including me, can go pound sand! :) Our banter doesnt mean much compared to the drama that you are involved in.
You are fine. No apology needed. Keep you head up brother.
 
hmmm... anythoughts on that bluesea disconnect switch? on amazon it says 32volt and 350 amp.
battery system being 48v hitting ~60v is almost double the rated voltage.
 
hmmm... anythoughts on that bluesea disconnect switch? on amazon it says 32volt and 350 amp.
battery system being 48v hitting ~60v is almost double the rated voltage.


Unless you can read the numbers off the switch (I can't) it is hard to tell which one it is. They all look similar and there are versions that go up to 60v 600amps
 
Unless you can read the numbers off the switch (I can't) it is hard to tell which one it is. They all look similar and there are versions that go up to 60v 600amps
all of their disconnects are only rated for 32-48v, afaik, and the 600amp one is currently grey, where as the red ones are only up to 350amp.
 
there should be a Class T fuse between any parallel batteries.
no its not, instead use a heat resistant mega fuse holder
and a simple bms for each paralel battery.

no expensive useless batrium needed
people can learn from this case and dump their batrium or install additionally a jk bms each paralel bank
 
What should I do with my 8 50Ah not DIY batteries that already have a BMS. Since they are only 50 Ah getting 8 Class T's set up would starve my children for a month.
Are these the dchouse/ecoworthy pizza boxes? You could put one class t on each paralleled pair (5kWh). That's how I'll be doing it (tho with midnite breakers versus class t).
 
no its not, instead use a heat resistant mega fuse holder
and a simple bms for each paralel battery.

no expensive useless batrium needed
people can learn from this case and dump their batrium or install additionally a jk bms each paralel bank

And you clearly have no clue what you are talking about. You also just as clearly haven't read the whole thread.
 
Are these the dchouse/ecoworthy pizza boxes?
No they are the *cough* Renogy batteries that Will destroyed on video.

I have 8 48v 50ah batteries cross wired, in groups of 2 . This gives my 4 wires to each bus bar instead of 8
Should I just get 4 Class T fuses? Why would that be better? I still would have 4 groups of 2 that could feed each other
 
And you clearly have no clue what you are talking about.
i know what im talking about i use the same type of bms (diy bms /stuart pittaway) its like the batrium but much much cheaper.
my paralel banks have their own seplos bms in dumb protection mode and 70v rated mega fuses on heat resistent fuse holder.

the diy bms communicates over canbus with the inverters. if something goes wrong in the paralel bank the seplos will disconnect it or the mega fuse blows. the fuse holder can resist an eventual arc or heat from the fuse.

additonaly all parts for battery build are flame or heat resistant nothing can burn in that room. all brickwalls and concrete, special cables(not the cheap pvc insulated) and so on...
 
What should I do with my 8 50Ah not DIY batteries that already have a BMS. Since they are only 50 Ah getting 8 Class T's set up would starve my children for a month.

Class T
https://www.mouser.com/ProductDetail/Littelfuse/LFT300601C $20 x 3
https://www.supplyhouse.com/Littelfuse-JLLN060-60-Amp-Fast-Acting-Class-T-Power-Fuse-300V $16 x 8

Or mrbf
https://www.mouser.com/ProductDetail/Bussmann-Eaton/CFBAR1-250SP $9 x 8
https://www.mouser.com/ProductDetail/Bussmann-Eaton/MRBF-070 $11 x 8

So, class T for $188 or mrbf for $160 - not as bad as you were thinking I am betting. Were it me I would do the class T right off the bus bar.

Save your children's lives ;)


Well, just saw your post, adjust the quantity count and it is very doable.
 
i know what im talking about i use the same type of bms (diy bms /stuart pittaway) its like the batrium but much much cheaper.
my paralel banks have their own seplos bms in dumb protection mode and 70v rated mega fuses on heat resistent fuse holder.

the diy bms communicates over canbus with the inverters. if something goes wrong in the paralel bank the seplos will disconnect it or the mega fuse blows. the fuse holder can resist an eventual arc or heat from the fuse.

additonaly all parts for battery build are flame or heat resistant nothing can burn in that room. all brickwalls and concrete, special cables(not the cheap pvc insulated) and so on...


The OP was using a Mega fuse in a flame resistant housing with batteries sitting on steel shelves. The problem was the fuses didn't extinguish the arc from 6 batteries dumping intonthe 7th. Minimum 750amps and max of 9000amps. That is based on a single cell going to a dead short. Mega fuse of that size style has an AIC of 2500amps.
 
Right on! But I certainly shy away from pressure contact based fuses and holders. Do you think Im overreacting?

At lower amps possibly. They had a few styles. One is a style with a holder and indicator. So it is covered and clipped into place.

When I have dealt with this sort of fuse before it took a screwdriver to pry a dead fuse out of the slot.
 

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