How do I know which is ground if they are all black?
Do you have a multi-meter? You can figure out the way they are wired by measuring the voltages from the balance lead.
How would I do that
90% of the messages you write in This post include the words “how do i”. I’m not sure you really know what you are doing. And that diagram is really bad and will destroy the bms. I’m sure the diagram you need is already on the forum but your best bet is the one posted by jmasta from the beginning. Only your batteries have each another single wire in between the rest
Dude the diagram you posted looks mostly right but why the hell did you swap the order of the red wire and the two black ones after it?
Edit: I looked at it again and that is not right at all if you haven’t figured it out by tomorrow I’ll draw you a new diagram of how to wire the cells into 12s and you can workout how they connect to the bms. Deal?
@krloz I have looked all over the forum for a diagram but couldn’t really find one. @pat.speed I think I understand how to do it now. Will post another diagram later today to make sure I did it right.
It’s just the balance lead wiring as I want to make sure that’s good.
Now you are missing one wire. In the middle middle where the series connection is there should be one wire coming off. Always remember this. However many batteries are in series add 1 and that’s how many balance leads there are. So in your case there should be 13 which when you add the one onto the middle cell there will be.
Now on a bms USUALLY there is only room for 12 wires. That is because it will USUALLY have b- which acts like one balance lead. So USUALLY you leave out the first wire because that is already connected to to the main negative lead which goes to b-.
That was kinda comfusing to explain. Just check the wiring diagram for that specific bms too just to be sure that’s how it connects
Please reference this post. You are basically doing the same thing but with 2x6S lipo. Your diagram is wrong because the red lead is always the positive end of the battery, which is cell 6 and 12 for you. The remaining black wires should come arranged in order. If you are not confident you should use a multimeter. Since yours came in 1 red wire and 6 blacks. You should measure the voltage across from the negative lead of the battery to the wires. There should be 1 that reads 0V, which you will not need to connect to the bms because that is directly connected to B-. #1 cell should read 3.7V-4.2V (voltage of 1s), #2 read double of that (2s). etc… your red wire should read 6s voltage.
I recommend looking up how to use a multimeter if you don’t already know.
Got it thanks