Measure the voltage as you charge and watch what happens to it
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when I charge with the BMS or the Imaxb6? I doesn’t seem to be a fault in the cell itself or the connection due to the issue being identical with multiple/all the cells.
like you want to see if the cell is reading 4.2v like the imaxb6 says it is?
I know the BMS is shutting off for whatever reason and not doing anything.
Yeah, Measure directly at the cell when you hit charge on the imax. See if voltage stays at 4v or spikes to 4.2 right at the cell
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I can really get to the cell terminals but I noticed when charging with my bench power supply that the balance leads give me the cell voltage so I’ll try it.
This time it decided to charge… UGH wth
tried the bms again still shuts off then turns green the moment I turn on the BMS
IMAX tends to be waayyyyy off on voltage reading, .2-3v on mine for instance, so I set higher end voltage for it to actually get to 4.2
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I didn’t think too much of it before, but could the issue here be that my charger is only putting out 50V solid? instead of 50.4
Looking more and more like the issue.
@BuildKitBoards
I feel like saying Bingo
Piccy proof
Uhhhhhhhhhh
This is not good. Looks to be
guess i’ll use my DC booster to get 50.4 and see if the BMS works as it should with the correct input voltage.
This charges does not look too easy to crazk open and look for pots to twist.
twas easy
No, that doesn’t add up still. Plug the charger in and probe individual cells. 0.4v/12 is a very small difference.
Unless your BMS is shutting off because 1 group is at 4.2 already
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this is hard because the jst connectors are in the BMS then. I would think when the BMS get getting near the end it needs the full input voltage it is expecting to have in order to function, but I know you are supposed to be able to use a bms with a lower charge voltage than intended and it should work.
I’m getting really good at walking the probes along the jst connector
It does not, you should have over 4.19 per cell when done.
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50/12=4.1666
I still think I should try to give the BMS the proper voltage and see if that works. Any ideas on how to read the cell voltages while the jst connector is in the BMS would be good. Getting to the actual cell terminals is tough but I could tear the sides off my shoebox paper based battery case to get to them.
Guess I shouldn’t be using this charger anyways. even if it was the right voltage.
time to see if there are pots inside!
damn, security screws and I can’t go borrow my friends set of bits.
Children’s scissors to the rescue!
Turns out no loose screw, it probably would have already blown up if that was the case. Looked like a screw due to the threads showing.
Not seeing any pots to turn on here.
It appears the plastic post broke because the PCB doesn’t fit into where it’s supposed to. The holes would line up but the wall that holds the fan is in the way…
Bad fit caused the other post to be under stress/ squeezing the PCB instead of being against other other side of the plastic charger case.
The other post has cracks in it from being assembled when it didn’t fit together properly.
Don’t worry. I licked all the capacitors to make sure they were safe before I touched it.
The triamgle ones?
They are easily made from a nail and a desk grinder
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Had me thinking what about a 12S3P battery in there and a vesc… I’ve got a set of meepo hubs I could try with 12S. Dunno how they would handle at that speed tho.
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I think they can, I will definetly try that eventually 12s3p will fit if you get creative with arrangement of cells
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You already got pretty creative with the cell arrangement lol
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Lol! Yeah 
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Hot glue does wonders for temporarily holding cells when you need to weld before gluing! 12s3p + 12s4p in the works!
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I was about to saw you were right, 50.2 volts didn’t make the BMS work.
Then I remembered that 50.2 is the incorrect 12S charging voltage that I have stuck in my head.
Set it to 50.4 and BAM
shit is charging up.
DC booster is screamin, but working now that I set it to .9A
I think I spoke too soon… It has stopped again for some reason, damn it.
lol think I have a bad connection on my charge port. Gotta check on that.
I hope I’m Posting this in the right place, but I’m trying to fit 21700 cells, 12s5p config on a vanguard flex 3. I have some of my kids blocks to simulation how it may fit. It’s a 8s5p front, 4s5p rear along with a Y connector at the VESC. The red blocks simulate the VESC. Please advise on experience splitting the battery packs. Thanks First Build.
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I see you’re going dual battery enclosures… 
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