35aud
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These smartbms, I dunno what it’s doing. The rate of drain sometimes jumps up. I’m glad I have these graphs…
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Cells at 4.07-ish and app said it’s only 68%.
The cells are sanyo NCR20700B 4250mAh 15a.
I assume designed capacity means the total ampere (4250*4 =17000 or 17 Ah for a 12s4p)and battery cycle capacity is the capacity of each cells which is 4250mAh. What am I doing wrong?
Probably making wrong assumptions.
Google xiaoxiang "designed capacity" "cycle capacity". First link.
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Thank you sir. That fixed the issue.
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I just wired up my LLT smart BMS and I am having the exact same issue - all seems well, but it won’t read any data from the BT module. I did not short anything to my knowledge.
Tried disconnecting the BT module, reinstalling the app, etc.
Also, I noticed it makes a high pitched noice when it’s connected. I assume that’s normal?
Edit: This is on iOS app, 12s, all cell voltages at 3.69V
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I contacted the Ebay seller. They are very responsive though their English is hard to understand.
Highlight of the conversation:
Suuuure, sounds legit. 
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Yeah, I tried all of those and nothing worked, I even tried to add a new BT module but no success.
It’s super weird what is causing this, maybe it’s software.
It used to work really well for me until one day it just stopped working. (Then the short happened after I was trying to manipulate my thing).
Now, there is a new BMS on it’s way to see if it’s going to fix the issue.
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Did that happen to you on iOS, too? I’ll try with android tomorrow to see if that does anything.
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Yes, the glitch is on ios. One day, I was writing settings on the BMS and it somewhat timed out, and then when I tried to restart the app, it became like this.
Android works perfectly fine, but I don’t really use an android phone, so it’s a bit annoying to carry one around just for the BMS.
But having a Smart BMS is super useful to detect stuff like this, I opened my enclosure and found out that a balance wire got disconnected.
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I can live with a dedicated android phone to troubleshoot stuff. Hopefully it’s just iOS that’s bugging.
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Well, I also tried to contact the Ios developer for this app, and he couldn’t help much either.
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Well now my app is saying I have 86% at 3.87 voltage. I thought I fixed the issue but turn out I didn’t. I just want the app to display correctly…
Didn’t you say your pack capacity is 17 Ah? Why did you set it to 4250 mAh then?
So before I had it 17000 mAh for design capacity and 4250 mAh cycle capacity. It still throwing me wrong percentage. I then change it to 4250 mAh to see if it gives me a different number.
Oh man, have you even read the endless sphere thread I linked? You’ll want to set the “Designed Capacity” to the full battery pack capacity, i.e. 17000 mAh in your case. Then set the “Cycle Capacity” to what you realistically expect to get from the pack within one cycle. If the battery is new, it will be around 80% of the full => set it around 13600 mAh and it should be all good.
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Bruh I read that and I thought it meant the design capacity is the theoretical value of the cell and the cycle capacity is the actual capacity of the cell which maybe less than the specification. 
Like who the hell made this app. So confusing.
Alright, So I have tried 6 different apps - iOS, Play store, the two versions on their webpage and even the two sketch apk files that the seller sent me by email (ofc on a sandboxed device).
None connects. Some at least recognize the device but then have an error connecting.
Yes, I also tried unplugging and rebooting devices.
I wonder what’s the best course of action? Call it a failure? Repurchase?
DieBieMS and FlexiBMS are impossible to get currently, else I’d go for one.
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tried the pc app? and I think there’s a special firmware for davega that can talk to these bms?
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