How to Solder B- and P- wires to a BMS?

Hi Guys,

This is a very noob question, but where do I solder the positive and negative leads to this BMS I got?

See attached for pics. Do I solder the wire where the hole is? Or on the silver areas to the left or the right. Or can I simply solder anywhere along there? I tested the continuity with a multimeter and it seems that the entire silver areas are connected (i.e. the silver areas around the hole and the strips to the right and to the left.) So I’m thinking anywhere there is fine?

Just wanted to confirm so I don’t destroy this thing accidentally.

Looks like its all the same, probably best to use the holes to solder into though, unless soldering along the other pad areas makes installation easier.

It seems that you only have load- and battery- terminals.

I would solder the wires through the hole and solder it in. Would be easier.

Basically motor controller negative and battery negative lead connect to the corresponding spots on the BMS. P is load and B is battery.

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Thanks! I just wasn’t sure what all that other surface area was for and if it was there for a reason. Will go through the hole as that will definitely be easiest.

I had done up this wiring diagram before receiving the BMS. Seeing that I have no CH-, do you know how I am suppose to wire the charging port? In my diagram I have it going to CH-, but that doesn’t exist on my BMS


charging port negative is typically P-

I’m not sure what the discs are for your BMS or if it even detects individual cell voltage or charge protection… But it should be fine for your charge port to go to B+ and P-… Might want to double check add I’m not sure.

Thanks guys. I appreciate the help!

Sorry for bringing up an old post. Was this diagram ok?

It’s fine as long as you are using the bms also for discharge

Its even easier if you are not using BMS for discharge.

P- to charge port negative B- to battery neg Charge port + to batt +

I have an 80A BMS and plan to use for charging, so I follow the diagram above?

Exactly 10 chars

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the correct for soldering is up (42)


so i have to soldering positive to positive and negative to negative with this bms

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like this

imagem imagem.jpg587x509 99.9 KB

And for soldering the bms, the step are this?