I have just finished wiring up my BMS and i tried charging my board with it. Everything seemed to be working, the light of my charger turned red and my battery indicator showed that the percentage of the battery was going up. But then my battery indicator reached 100% but the light of the charger did not turn green. Is my BMS still balancing or what is the problem here? I am a little worried to overcharge my battery, so i unplugged the charger for now. Or is my charger never turning green, because my ESC consumes power from it, because the ESC and the charging port are wired in parallel?
Most bms just balance when reached 4.2v. Plus check if your battery indicator is set to the right voltage. Usually they multi voltage indicators which need to be set to the right max voltage. If you have a multimeter you can check the actual voltage of your pack to make sure all is good.
I have 4x3s batteries in series and am wondering which balance wires actually connect to the bms because there are 4 coming out of the battery but only 3 are used??
How do you know if your BMS has a ground port in the balance plug? if so would you use the negative balance wire first then for the next 4 packs use the positive wire first? im using this 12s BMS from battery supports.
Should i hook up the BMS using all positive leads first based on this BMS?
Yes you balance plug has a ground pin, you can tell because you have 12 positive balance wires on the plug(one for each cell) and then there is a thirteenth wire on the left. you can leave this wire unatatched, because you will be connecting that negative balance wire to your B- port on the bms. I’m assuming you are discharging through the BMS, although the wiring will be that same whether you discharge or bypass the bms
No my BMS has only 12 balance wires
?? the one you linked has thirteen. Either way, you connect all 12 positive balance wires the the 12 pin connector in order, and attatch your negative balance wire to the B-
Oh im sorry i ment to send the 12s 100a version same bms just 12s… ive attached the link below…
so can i just follow this diagram for my 12s battery supports BMS?
Yes. Are you discharging through it or bypassing? This diagram isn’t accurate for discharge BMS
The above diagram is a modified version of the original below.
The Battery Supports also know as Supower bms does not have a ground pin on the balance connector port. It also does not have a separate pad for charging ( C-) You will connect the charge negative wire to the (P-) pad. The battery negative wire to the (B-) pad The battery negative wire to the ESC for bypass bms or The Esc negative wire to the (P-) pad for discharge bms Battery positive goes straight to the ESC positive and charge port positive.
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Hi, I have built a electric longboard. I used it one summer but I wanted to upgrade. It was a hazel to unplug the battery’s every time and plug them in to the balance charger.
Therefore I decided to add a BMS, 3 pin charge port and a small battery presenting indicator for easy use… I decided to bypass BMS. I started with wiring the cables like the picture below, but forgot plug in the motor ore the balance wires to the battery’s(I did not plug in the XT-90). When I plugged inn my charger the BMS became super hot(to hot to touch). I though it was because my battery balance leads were not plugged inn. Therefore I plugged in my balance leads and tried again. This time the 3 pin charge port and the charger welded together. Then I plugged in the XT-90 to complete the main circuit. This was a bad decision on my behalf, because the battery’s started to expand, my cables and connecters started to smoke, and the VESC MOSFETs melted through the heat shrink. This lead to all my electronics getting destroid. 
I believe the wiring is the problem. I did not have the motor plugged inn. Can this have an effect on what happened.
Can anyone please take a look at my wiring an tell me what I have done wrong. Thanks 
Looking for help with people who bought a D140 through li-tech. Does the 12s unit have a 9 pin and 4 pin or 2 9 pins with the last 5 of the second set unused? Pictures on the forum show 9 and 4 but the site shows 9 and 9
http://www.litechpower.com/product-detail/HCX-D140LI12S15A-05.html#
if you connected 5 more lipo batteries in parallel to this diagram, does each battery share all of the connections with one of the existing batteries?
I’m a little confused about how to connect the bms to a set of lipo batteries that are both in series, and in parallel.
Yes, you parallel the main and balance connections