Bms Discharge voltage 3.6V?

ESK8 Electronics
1

So I burned my BMS (which might be the cause of problem in the title) by plugging balance connectors with reversed voltages. I have a spare BMS, but to check if I got balance wires correct now, I’m still using the burned BMS (only the resistor by lowest voltage balance wire port got burned. I changed the balance wires and plugged everything again into BMS, nothing else is burning thankfully, but voltage meter doesnt light up and when I checked discharge port with multimeter it showed 3.6V which should be 10x bigger (10s battery)

Is this due to that BMS is burned or I wired something wrong?

My diagram:

Diagram by bestech:

One thing to note, I just assume those wires are e-switch and I just wired them together.

2

Most likely yes. The balance circuit is damaged. The bms is not going to output

3

Connected new bms in same way, nothing smoked in its part. But it’s still outputs 3.7V

Connecting what I think is eswitch doesn’t change it

4

Idk why, but disconnecting and reconnecting voltage meter fixed it

1 Like
5

Does that BMS even provide an adequate discharge current?

6

60A, yes, but as i said , disconnecting and reconnecting voltage meter at discharge port fixed the problem completely

7

Hm, not a bad size for a 70A continuous BMS

8

How can you check if a resistor got burned ? I have also plugged in balance wires in wrong order and now during acceleration my bms shuts off. Shall I probe resistors with multimeter and check if they are same resistance ? Shall I have motor running during this process ? If it is a small resistor I would be tempted to replace it myself.

9

Try to find the burnt ones :smile:

IMG_20170826_162050_001.jpg2461×3281 2.38 MB

10

Hahah! Mine look good :confused: so I have tougher problem :wink:

11

Multimeter probe in diode test/continuity test mode…