BMS wiring issue

[tombenn444]

Hi everybody any help would be great this is my issue. I am rebuilding a 48 volt lithium-ion battery pack for my evike. I ordered a BMS chip from Amazon's to replace the one that was burnt out. when I started connecting everything I noticed that the previous balance wires seem to be connected differently with one positive red wire on the positive side of the first cell and the rest were white wires which were connected to each negative side. The one I got in the mail is polar opposite and more like most BMS I've seen online. I hooked up the one I just got as per the instructions and it fried my battery charger, this is the first battery pack I'm building.

 

[docw009]

Looks like you didn't recognize how your cells are laid out. The wiring is wrong,



Start over again with the black wire from the BMS going to the most negative end on the battery. Sequence the remaining wires in order, and the last balance wire will be on the most positive end,

Edit: I gave the name B0 to your B- wire, and B13 might be B+, but you should be able to adjust.


DIsconnect the balance harness from the BMS when you wire it. It's always a good idea, before you reconnect the harness, to put the negative probe on your votmeter on B0 and then walk the positive probe up the pin locations to B13, making sure the voltage increases steadily in sequence. It's pretty easy to mic a pair of blance wires.

 

[tombenn444]

Awesome I'm wiring it up now thank you, I must have had it completely bass ackwards I figured the b0 wire was supposed to go on the negative of the last cell; the end of the line essentially

 

[docw009]

`B- does go to the negative end of the last cell, but it looks like you picked the last cell, and put it on the wrong end. You had it on the postive end, the side with the cardboard washers,

 

[tombenn444]

Here is another angle the spots in yellow are the original locations of the previous balance wires. The second picture is how the original BMS was wired up