Looks good but I’d bump up overvoltage release delay a bit as this will trigger an overvoltage cuttoff too quickly. I think I have mine at 8 seconds. This will allow your bms to balance longer. You may also find as you cycle the pack a few times it will naturally settle to a lower delta. This happened to the last pack I built. Also, charging more slowly lets your bms do an active balance more easily as it’s got a pretty limited balance current. Iirc it’s like 65mA or something like that.
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then hook vesc negative to C- on the BMS. also connect charge port negative to C- on the BMS.
Some BMS have a P- and C- for the load and charge, often these are hooked together anyhow, some just have C- for both.
Ok thanks 
thanks, this helps. The one ill be using does have a P- but in my email, i did refer to the BMS shown in photo1
Hey kids.
12S5P in the planning.
What would you do?
Old trusty P42A
Or the
50S?
The price difference is small enough for me to make the jump.
But I am wondering if the Samsung cells will be reliable workhorses like the P42A?!?
I would stick with p42a for a 5p pack.
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I have some .15 x 100mm I could section out if that would work.
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You would get kisses and hugs.
Let me see if I can calculate how much I need.
Hey kids.
I have started on a 12S5P P42A.
To work with my enclosure I am doing it stacked.
I’m now pondering ways to minimize overall pack height.
I was going to do the series with 2 x 14 awg.
But now am pondering these things copper braids inspired by an MBoards post I just saw…
I have not done the braids before.
Is it more challenging?
Learning curve?
Any links for good thin braids like these?
Am I being dumb and worrying about 2mm height difference?
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Cant get an answer from LLT. i got their 10-17s bms. first time using it and i can’t get the settings to write anything other than 13s… You can see the extra cell group. its a 12s pack.
I followed the harness wiring correctly, stopping after the first 13 wires.
Any idea?
Does anyone know what this extra +/- lead is for? Just bought a new 12s LLT SmartBMS and have never seen this before. According to google translate, the lettering above it says “Switch”.
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It can be more challenging as the solder likes to wick into them and they can get very brittle. It’s really not too tough, you might be able to find some braid on ebay
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Ya that’s for the switch lol you can attach a switch on it to turn on and off the discharge port.
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You did not follow the diagrams, you have to solder together a number of the leads to make it 12s. You should be able to get the diagram from the product page in a pdf
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If you are making a segmented pack you will have exposed connections unless you take an extra step.
To prevent solder wicking, use a flat head screw driver as a heat break behind the solder blob when you are soldering.
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yea thats the issue, There is no diagram for this unit.
Normally the first black wire is for battery -
then the first white wire hits the positive of battery -
then each wire hits the next positive terminal of every group. - I used a total of 13 wires for this 12 pack.
Which part did i mess up for this unit as it obviously isn’t wired the same as their standard 12s bms.
edit - i see now theres a text link hidden on the page that shows the diagram…