My Xiaoxiang smart BMS broke due to water damage, so I had to order a new one, but for some reason the max voltage is set to 3.9v, and it wouldn’t accept any value higher than that, and because of this the battery doesn’t charge and I get the overvoltage warning despite each cell being at 3.7v.
You got a lifepo bms. Return it and get what you should have in the first place, a li-ion bms
You might want to check if the bms lets you set the cell type though
Use the iOS or pc app to program the bms correctly. You have the settings from lifepo4 on that bms. But you can easy change that.
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I double checked my order details, and the product is listed as a li-ion BMS, but maybe it’s a typo or something.
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Well technically lifepo4 is still in the liion category. Check your app settings, you can allow to charge to 4.2
I tried doing that, but it just gave me a warning message saying the only valid values are 3.6-3.9v as the overvoltage.
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That is because you have a double over voltage protection. You can adjust it easy with the pc. and I think too in the iOS app.
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What’s the computer app called?
Its on the xiaoxiang site
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Hi guys!
I got a Smart BMS and when I’m connecting to it with my 12S4P 40T, I got nothing like the apps in videos.
I can’t see parameters or informations about battery :
i don’t know what the configuration app in android is called, but the one for iphone is called XiaoxiangBMS and it has the full configuration options, you can even rewire the balance leads and change the s-counts.
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You want the mobile Android app from their website
https://www.lithiumbatterypcb.com/smart-bms-software-download/
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Just an addition to your comment. The BMS must also be reconfigured by adding/ removing the solder shorts on the PCB to whatever s-count config is wanted. Otherwise connecting a 12s battery to a 10s config would be really bad.
Maybe this was what you ment. I just wanted to make it clear to anyone before they blow anything 
Here is how it looks on my 10S bms
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Where did you get that document? Can I see the full thing lol?
It’s from the datasheet for the cell monitoring IC used in this BMS.
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Learn something new every day. 
yes. I literally just did this a week ago on four of them, went from 14S to 12S. You can also take their 12S one to 14S. They’re identical. And both will go as high as 15S.
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Thanks! I see all the information now.
I just don’t understand why Dashboard show me 100% and All my cells are at 3.8V.
But the charger is still on red light so I’m gonna let it continue to charge…
Yeah that indicator has never worked for me