Sorry, can you explain?
I don’t understand your message 
Sorry!
What is the voltage measured with a multimeter from the battery negative to the battery positive? Not on the BMS, but on the battery itself.
Every battery has 11.3v and the total in serie is 33.8v between B- and B+
Can you make a picture how it’s wired up now?
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Yes, sorry for the caos 
maybe i see it wrong, but did you bridge the black balance wire form pack one to pack two? if yes, why?
Based on the suggestion of @b264
With or without the bridge, the tension between P- and B+ is very very low 
Ok i have overseen that.
Just didn’t understood, as in this diagram the - is only from the first pack connected
Seems i‘ll learn something today too 
Yes, in fact the tension with or without the bridge is the same in out from the BMS (between P- and B+). The black wires on the balance port there are the same as on the negative pole (B-), are soldered on the same point.
But i don’t know why the tension is too low 
If the XT60 series connection are unhooked, then charging would still work. This is the reason. To separate the charging function from the discharging function. If the XT60s are connected, it is the same. This should charge correctly without any XT60 connected.
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Just to get it right, if to unhook the xt60 I would only charge through the balance leads? If yes, it would mean that if I have a 4a charger I would charge 4a through the leads instead of the 50-100mA which usually used for balancing.
I set them up to charge if the large wires are unhooked; yes. Some folks might not. I know a lot of folks don’t.
A 22AWG wire should handle 4A just fine. A 24AWG wire should handle 4A also but it’s basically at maximum capacity.
I just like the charging and discharging to be separate functions and each one works independent of the other. So, I don’t rely on the discharge to be connected in order to charge.
The risk here is if one of your large series connections came loose on the road, the entire battery current would be going through a balance wire. So there is a risk. It depends if you’ve made your series connections robust and used cable-ties on the XT60. To be safer, connect the black and red balance wires together through a 5A automotive fuse or leave them unhooked (meaning discharge must be connected to charge)
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Thx for the explanation. Now I understood why some people here don’t recommend 8 or higher amp charger. Never thought about it. Always thought the balance wires just need to handle the balance current which is kind a tiny.
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Hi guys, my BMS was burned and this was the cause of low voltage in output. I tried with new BMS, like this, and everything is ok. The tension between P- and B + is: 33.7v the same of all batteries in series.
Thank you @b264 and @Andy87 for the support!
I am learning more and more things here and I can’t wait to try the skate
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