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Charger keeps burning out

Withered+Flame

New Member
Joined
Mar 16, 2023
Messages
30
Location
Alaska
Whenever i hook up:

To 16 of:
with this:

It makes a massive spark, and chars whatever node I'm hooking up into black. This effect is present with or without bms.
The charger does not charge. It blows the fuse every time Ive tried it (3 times).
---
My phone also cannot see the Bluetooth module on the bms, even when i press the power button on the bluetooth module.
The bms heats up to a searing temperature even when nothing is going on so long as its pluged in.

I followed the instructions here:

I will provide as much info as necessary to get this fixed.

EDIT:
The voltage is around 1 volt less when i measure p- to battery + then when i measure
battery - to battery +

Update:
I did get the positive node and negative node switched around, I corrected that.
Connected to app, and it shows:
F42F5CB1-CD7C-456B-91DD-05AF4469CB84.pngCBF5D9C9-859E-4D84-A889-9C36FC9E9F04.png

I tested the balance wires and they show increasing voltage in increments of 3 when having one probe on main negative and another probe on progressively higher positives. 3.29, 6.5, 9.1, and so on.

I tested the cells and they are all around 3.28 volts.


I would like to try everything I can before I conclude that i destroyed my bms and buy another.
 
Last edited:
Can you post pics of your battery? Add the charger leads with power disconnected.

Do you have smart BMS screenshots? BMS known to be working?

And of course you know the black cell terminals are positive, right?
Made the update to main post in case anyone else wants to follow along. Screenshots included.
 
Wow, what are the BMS settings that let cells get above 3.65V?
Are the actual cell voltages, measures at the cell terminals 5V?

If so you have to bleed the voltage off ASAP to save you cells.

Cell 3 balance wire might be suspect connection due to low reading (artificially elevates cell 4 voltage.

Would like to see a pic of battery wiring too.
 
Wow, what are the BMS settings that let cells get above 3.65V?
Are the actual cell voltages, measures at the cell terminals 5V?

If so you have to bleed the voltage off ASAP to save you cells.

Cell 3 balance wire might be suspect connection due to low reading (artificially elevates cell 4 voltage.

Would like to see a pic of battery wiring too.
I don’t see any prospect that briefly connecting a charger wrongly can have actually overcharged the cells (would actually have taken some energy out of the cells). Seems very likely the OP has either damaged the BMS and it‘s reading wrongly, or it’s been connected incorrectly from the beginning.

Best thing he can do is as you said, measure the cell voltages with a multimeter and probably disconnect and discard the BMS at the same time.
 
Wow, what are the BMS settings that let cells get above 3.65V?
Are the actual cell voltages, measures at the cell terminals 5V?

If so you have to bleed the voltage off ASAP to save you cells.

Cell 3 balance wire might be suspect connection due to low reading (artificially elevates cell 4 voltage.

Would like to see a pic of battery wiring too.
The cells are not that voltage, i checked. 3.28V. I also re did the balance wires, and they are ok.
Look under the images in main post for this information.
Its now reading 0 volts on all battery cells and a -40 C temp. I think this bms is done, ill try once more tomorrow.
 
If a -40°C temperature is being reported then the temperature sensor is not installed or is not functioning correctly. Some BMS will not work right unless the temperature sensor is reporting a value (in an acceptable range).

Given the odd readings, I would check the continuity of the balance leads.
 
Polarity is fine on all cells and i re inserted the temp sensor. No dice, same readings. Am going to buy a new one. Does overkill solar ship to alaska?
 

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