not 100% sure the relationship between JBD and LLT but I’m pretty sure now all these BMS come from JBD so i updated the title.
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Not sure for certain what the relationship is there, but JBD is the manufacturer, LLT is a reseller.
I think that when those bms first became prevalent in our scene, most people were buying from LLT and hence why we associate the JBD bms with LLT.
Can’t beat the prices buying direct from JBD on aliexpress tho… unless probably on taobao 
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if only i listen to myself quoting you the first time…
thanks for reiterating. reiteration is key.
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LLT also has some modifications going on with some boards I think. My JBD 22S 50A and LLT 22S 50A BMSs have slightly different PCBs even though they are supposed to be the same thing
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Thats definitely interesting. Would love to know what the actual differences are and whether they are mods by/for LLT or just different revisions from JBD
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The LLT version had more mosfets and beefier bus bars. I think the JBD version used the same PCB (I think) but less mosfets were populated - which is interesting for being rated for the same current. Though it’s possible it uses better mosfets to compensate, I didn’t look up part numbers and datasheets.
It’s possible that it’s just different revisions, but I bought them about a month apart, so relatively close to each other. That said maybe LLTs stock was old to begin with. No idea
I’ve seen less mosfets populated… be the difference between JBD boards at different current ratings.
I’ve got a JBD bms with 22 wires I’m connecting it to a 20s battery. I connected 20 wires going from black. What do I do with the last wire which is red?
My bad response, I mis-read.
Mathematically, you missed a connection.
Black would go to negative pole.
Red to positive pole.
White on all groups in-between.
Make sure black actually goes to negative marked on the BMS.
I mis-read your specs.
Sorry for not reading closer.
Does your model number start with APxx or SPxx?
If you can get the model #, I can help you find the right diagram.
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They are different per model. thus @A-damW’s questions.
Iv’e seen ones where the last wires just get ganged together.
and others where intermediate pins are expected to be ganged together.
sorry I changed what I’d written above and had made a mistake in my description and there’s another wire. I found a good diagram
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I intend to use the little JBD 14S BMS for a 10S pack.
What is the practical way to jumper the 9th p group
I do it exactly as it’s drawn on the diagram, join them all together just after they exit the bms and then just continue one length out to the battery
Are you using the SP14S004?
Different cell count bms’s use different analog front ends, with different termination schemes.
If you are using the SP14S004, here is the correct termination for 10s use:
Source:
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I have to double check the model. All I know is it is tiny…
Looks like it.
Thanks for the save @A-damW
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Totally welcome!
I would be sad to see such a cute little bms let out the magical smoke. 
+ 
= 
To illustrate, here is 10s for the SP17S005 (SP14S004’s slightly bigger 17s brother)
Quite a bit different.
Here is all of jbd’s common bms wiring schematics, maybe some mod could pin it?
https://jiabaida-bms.com/blogs/content/jiabaida-all-types-of-smart-bms-wiring-diagram
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