12s bestech bypass wiring sanity check please

Please can you helpful souls take a look at my wiring plan before I switch the soldering iron on…

Also I’m soldering the bms wires to the bms one at a time, what precautions/ order do I need to follow to avoid killing it.

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Do not plug in the balance leads until you checked them at least 2 times back and forth

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And make sure to connect the balance leads last. Connecting them before the main leads has lead to dead bms modules in the past


Does it matter that they will be connected one by one as I solder?

I don’t really know honestly, I highly doubt it would though. Why are you soldering it anyway?

one by one is cool, as long as you plug the main negative in first. then plug in the balance leads from lowest to highest. eg 3.7v first, then 7.2v second, etc up to 12s (whatever that voltage is).and by main negative i mean b- so what plugs into the fat lead off your battery

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Wiring security, lower profile, haven’t got a plug :rofl:

Ahah ok, actually I guess it would have to work beacuase I have my bms setup without the last lead since it’s 12s but a 13s bms

before plugging into the balance balance port, check voltage for each lead.

so, attach voltmeter negative to pack negative. then measure each balance lead in sequence. ensure voltage changes in cell voltage.

oh wait, this bms doesn’t have a lead jst connector? ugh… you just made this harder than it has to be. jst connectors are secure, no need to worry about “wiring security”