Need feedback BMS diagram

Looks right.

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……

Ooh ahh

So organized and easy to… follow

On a more serious note make sure you get your balance wires in there, but besides that it looks fine.


Here’s another diagram that frequently is passed around.

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thanks for appreciating and sharing @b264 and my work!!!

:+1:t4:

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It’s good stuff. Brian sent it over a little bit ago and it’s worked wonders for my simple brain lol.

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I’ve actually been using this wiring more lately

You could always omit the lights circuit too and it will work fine, but you’d have a place to add it in the future if desired without moving the big wires around :+1:

On some BMS that do not have a C- port, then that wire goes to P- also. But if the C- or CH- port is there, always use it.

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I had assumed that the only difference between the two was choice of terminal for the loop key, good to know.

Thank you very much. Your diagram much clearer. Thank you all!

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Yes it is, good luck with the build! :call_me_hand:

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can someone help explain this diagram for me? Sorry, I’ve been trying to decipher it using it to model my first battery build and I’m a little confused about some things. For example, why is the fuse connecting to the positive lead on the battery broken at that spot that reads (CH+) and (CH-)? Is the CH- on the PCB board a negative charge and then the fuse is soldered inbetween a positive and a negatively charged lead? Is that correct? (I didn’t think you wanted to connect a positive and a negative lead).

Those gaps are where your charge port will go (often a 2.1mm barrel jack or xt60). The other gaps are where the motor/esc (usually an xt60 or xt90) and the lights go, respectively.

the fuse in this diagram is in series between the neg(-) of the barrel jack and the battery b(-)

does that help?

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@iamasalmon yes that is super helpful! I’m so close, here’s a photo I’m just not sure what to do to finish the charge port and do a loopkey, and how to finish wiring the BMS.

I have male plug for the JST coming in the mail. Can anyone just draw on this image in red and black how I need to wire to finish this up? I would be forever greatful :pray: :pray:

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Assuming “bypass” wiring configuration:

Connect A to C with 22AWG or 20AWG
Verify the the balance connector is correct:

  • verify B0 on correct side
  • verify B10 on correct side
  • absolutely DO NOT accidentally short anything out
  • Verify with multimeter that A to B0 is exactly 0.00V
  • Verify with multimeter that A to B1 is around 3.76V
  • Verify with multimeter that A to B2 is around 7.52V
  • Verify with multimeter that A to B3 is around 11.27V
  • Verify with multimeter that A to B4 is around 15.03V
  • Verify with multimeter that A to B5 is around 18.79V
  • Verify with multimeter that A to B6 is around 22.55V
  • Verify with multimeter that A to B7 is around 26.31V
  • Verify with multimeter that A to B8 is around 30.07V
  • Verify with multimeter that A to B9 is around 33.83V
  • Verify with multimeter that A to B10 is around 37.58V
  • Verify with multimeter that A to B11 is around 41.34V
  • Verify with multimeter that A to B12 is around 45.1V
  • then plug it in

Connect A to ESC negative as 12AWG or 10AWG
Connect B to loopkey_positive as 12AWG or 10AWG
Connect loopkey_negative to ESC positive with 12AWG or 10AWG
Get rid of 2 pin JST, can only cause problems. Only snip one wire at a time
Connect (solder) charge port positive to B/loopkey_positive with 22AWG or 20AWG
Connect (solder) charge port negative to fuse with 22AWG or 20AWG

If you need a “lights” or accessories circuit: (anything being powered other than an ESC)

Connect D with 22AWG or 20AWG to lights_negative
Connect loopkey_negative/ESC_positive with 22AWG or 20AWG to lights_positive

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Awww @b264 thank you so much you’re an absolute G!! This is wonderfully described and I’m super grateful you took the time for me man!

In TRUE @b264 form :pray: :call_me_hand: :call_me_hand:

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@b264 what do I solder D to if I’m not using lights or anything?

is that a PLASTIC charge port?

shame…shame on you (at least it’s fused) :crazy_face: :crazy_face:

If you’re not running any aux. power, heat shrink over the end, or desolder it… it doesn’t go anywhere on a BMS bypassed system except aux. power

EDIT:

I have a couple of other comments… non-catastrophic… so I’ll see if you can figger 'em out…

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Alright kookster, I’m trusting your insights, and thanks!

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are there non-plastic charge ports?

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yup…
10amp ones are difficult to find…

you can find 4-5amp ones all over amazon…

just get one that matches your charger jack and at least equal in amperage rating of your charger…

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I just ditched the barrel jack and am using an XT-60 now instead. Which is also plastic :sweat_smile:

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