BMS wire help -

Honestly I don’t understand why the Balance port are connected to the - in this Hobbyking schematic.

Si i did it by myself, I should have this

image

Then I don’t care about my P- ? assuming that it is the discharging port so

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You don’t use the wires for the load in the hk picture. The rest is the same like you was drawing.

And yes, just forget about the p-

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Okay so my drawing is good.

Thank you for your help, much appreciated !

Hey again ! Restarting this thread because I have another problem, I have 8 input on my balance bms and 9 on the one that I welded for my 2x4S in serie,

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The one Above was shipped with the BMS, so I guess i’ll Need to weld it to my battery balance wires, and the one below is my battery output.

I guess I won’t have to weld the positive of the battery balance right ?

That’s because you aren’t connecting to negative balance wire there. It has 8 ports for 8 positive wires. The negative balance wire is going to the B- port on your bms

Here is my wirings

image

Just tested it with the voltmeter, it sounds like the black wire at the full left of the picture is the negative one and the 8 others are the positives, sound ok there.

Can you tell me wihich tension I should have when testing « Battery 1 » and the negative pole ? I don’t know If i should have 33.6 or 4.2V and I don’ wan’t to connect it the opposite way ! Thank you for your tolerance…

Anyone ? 10char

Should be like this, just for your 2 4s.

Where the big black wire goes inside is the first battery. Where the red is going out the second battery. Same with balance leads, you start counting on the first cell

Your balance - is complete from the bms. So you need to skip the first black wire comming from the battery to the bms. The rest of the lipo wires you connect. For the second pack the same. Skip the black wire and connect the other wires in the right order to your bms. Like this image

Okay so basically I understand what you are explaining. Looks strange though because one tutorial on YouTube was explaining that I needed to cut one positive wire On the balance, maybe one shematic would be way simple to see what we are talking about,

image

Gave me a headache to drow it, i over satured the colors so you can see them easily, is it ok like this ? (I also whrote the batt numbers on the BMS !)

You mixed the order on your balance wires from the lipo pack. First is the Black wire and from there count up. In your drawing you took the red one as first and than counted up.

So for the left battery only here ?

In this order image Just you have some more wires between black and red. Skip the black from each lipo pack and wire the rest up. The red wire is the last wire.

I tried to draw it up. Hope you get it…sorry i‘m no Picasso :sweat_smile: image

It’s already late over here and I don’t want to make a mistake, so would be nice if somebody could confirm if my drawing is also correct. Maybe @b264 if you have a minute.

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I don’t see any issues with that. If it’s late and you’re tired though, it may not be a good time to be hooking up lipos :slight_smile:

Put a loopkey in that + wire on the VESC though

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Thx! Yes loopkey definitiv don’t forget :sweat_smile:

Thank you very much guys !

Honestly it’s just perfect, i’ll have a look at this this weekend because i’m onto others things right now and you’re true.

Yup the Loopkey lol, il already have it, an lcd display and all, my board is already fully fonctional, Bms will be the final touch :smiley:

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That’s great! Take your time with wiring things up. Double check everything and measure the voltage that you see it rising up in 3.6v steps. Main leads need to be connected first than the plug for balance wires. Ah and double check everything once again before connecting everything :sweat_smile: It’s super easy to burn up a bms… So take your time :wink:

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And could I use some small Awg wires, like 24 to wire all of this ? I also have some big 12 that I used for the rest of my electronic but it’s really big to weld on the BMS ! I’m asking that because since the bms is wired in Parallel the output current of the batteries will always pass through the bms even if i’m Not charging the board, in this case maybe I could overheat or put too much amps on thoses wires ? (not taking about the balance wires though)

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