BMS wire help -

Hello !

Just received this BMS from Hobbyking : image

Why do I have only 2 wires going out of it ?


I’m supposed to wire it like this but I have only 2 output and I don’t even know what are they ! Any idea ?

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I think those two wires are either chargeport or battery + and -. I would try to find a proper diagram of how it’s supposed to be wired (if you haven’t already) and if not, hopefully someone with the same bms can help you out. The big plug on the side is what the balance leads plug into

Can you link to the bms? I think those 2 wire are a e switch or temp sensor

This one :

Yep I know about the balance ports, i’m not at home right know but it was surprising to see only 2 wires pre welded, maybe the others one needs to be welded …

image You mean this? It’s the temp sensor. You need to solder your wires to the pcb on the right terminal.

I guess you want to use the bms for charge only right? Than the Charger + goes directly to the battery + The charger - goes to the bms c- and than from the batt cathode - to the battery -

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this is a charge only module - 4amp charge, 10amp discharge. do not wire it for discharge.

B- is your battery negative, either P- (load) or C- (charger) is charger negative.

Thanks ! So the schematic that I showed over should be good ? (Without balancing wires) Edit— My mistake, it’s without discharge wires

No it’s wired as discharge

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Then this one should be ok without the switch.

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Can I like my own comment? It’s all written there :sweat_smile:

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No still wired as discharge :grinning: remove P and split B- to battery and vesc

Haha sorry it’s easier to look with a Shematic, thank you!

Just like that image

still wrong



The contacts are named different on his pcb. The p- in your drawing is c- on his pcb. The b- I can’t see how it’s called on the pcb. Maybe b-


@Alex753 if you can make a picture of the top of your pcb we can say you exactly where you need to solder which wire

That what I was looking for, i’m not at home as said but I just got this pic


Looks like I have C- , P- and the last one I can’t really read, P or B.

Thank you very much for your help, i’ll send some better pics when i’ll Get home tomorrow if we can’t read correctly !

It’s B- wire it up as @Andy87 explained

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I found the drawings on the hk side :sweat_smile: image

So the Charger + directly to the battery + The charger - to c- and than from the bms to the battery - how it’s shown in the drawing.