Few meepo/china packs that I had to rebuild/replace bms or cells were actually decent. Fishpaper under balance leads, fishpaper between groups, everything secured in place. I was actually amazed.
Old meepo pack vs new 10s2p p42a pack with meepo bypassed bms:
Ya same here, I was shocked that the balance lead were nicely isolated.
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For anyone having a similar issue. LLT checked the PCB which was ok and asked me to check temp sensors and connections. Temp sensors were ok. I reconnected everything, tightened NESE tabs and it is fine nowā¦ seems something was loose that I missed. Cheers to all that read this and apologies if this wasnāt the right thread.
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Iāve got a BMS with B- , P- , and PC- . Anyone got some thoughts on charge only wiring ? Originally the PC- went to the charge port negative, P- went to a xt60 negative, and B- went to the battery negative.
@PickSix24 you would technically only need to wire pc- and b-. what used to be p- would be gone. Youāll need to make a direct connection from battery to esc rather than through bms
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Ok thanks, thatās what i was thinking. The labeling through me for a little loop. Glad I wrote down what the original connections were lol.
this needs a reference topic we always answer this question with.
In the mean time Iāve seen Beautiful diagrams! NO WORDS (SERIOUS). with a link to specific diagrams. but I didnāt find the one to link to. sry.
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Yes. Thanks.
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most smart things find the thread and search for posts by brianā¦
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I see you had experience on this topic:
Which I think is. a decent reference thread to point people at in the future.
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yupā¦ that was my introduction to bypassed BMSāsā¦
myā¦ we grow up so quickly when we apply ourselvesā¦
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I more or less got confused by the pc label. Hadnāt seen that one before.
Lol I watched some dude on YouTube for 30 minutes and still didnāt understandā¦then I went on to scare the shit out of my classmates by making a bomb in a woodshop
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knock-knock on w00dā¦ I still havenāt had the bright-flash, burn multi-meter probe, 
I have a healthy respect for the damned thingsā¦ we had a customerās bike catch on fire in the shop because of a lithium fireā¦ the bike didnāt burn, we cut it out with bolt cutters and threw it in a 5-gallon bucket of waterā¦ and watched it boil the water
his electrics were all fucked up and he was throwing 20v at his 12v litium battery
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This is exactly where I was a couple months ago and @b264 was awesome helping me wire my BMS charge only. Hereās his instructions for dummyās which I still reference
Need feedback BMS diagram
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Did i just kill this cell? This is my first time seeing this out of about 6 built packsā¦ I was welding away and this was probably group 3 and 7th time doing this today so settings have been establishedā¦ The first weld on this cell was fineā¦(negative side as well) second weld (bottom left) sparked some followed by a mild sizzle and bubbling for a secondā¦ There is a oily kinda residue now and has a very unique smallā¦
All the positives are connected already. Do I need to disconnect that end as well to get a real reading? Or can I get a reading with all pos. Connected and just that neg ens of cell disconnected?
Thx
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gurgle
RIP
I punctured a cell once. did exactly that.
those welds look a little hot, esp. if youāre blowin through
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you probably blew a hole in the cell, that smell is typical for lithium batteries
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