I wish I had read this yesterday. Guess I need to add some extra protection between the p-groups
Has that BMS been working well for you? I bought an identical one recently but noticed itās missing a component:
none of those packs are mine
Ah I just realised
Sorry to interupt the chat but i just welded part of my battery together and the left cell is 13 degrees hotter then all the other ones. I dident short it out or anything. just a bit confused
Heres another picture
That 10AWG wire is good for 55A continuous and 110A for <10 seconds.
That 0.25" tinned copper braid is good for 40A continuous and 75A for <10 seconds.
Double those for double the rating.
Is this a normal thing for the cells to do. I replaced it with a fresh one and the same thing occured
They might be balancing. Measure the voltage on the cell and the voltage on the P-pack. If they are off at all, they will immediately begin balancing (charging the lower one, discharging the higher one)
You donāt want more than a 0.1V difference and itās better if they are the same before the weld.
Ok that makes sense now. It was at a lower voltage than the others. Should i just weld it back on and leave it or charge it up to the same voltage?
Each strand of the tinned copper braid is good for 40A, so I have 3 lines of it connecting each series together. Thatās fine, right?
Iāll double up on those power lines from the battery to ESC. Would it still be ok then have them conjointed back into a single 10 awg wire right before the ESC? The ESC has power input as single 10awg with a xt90 connector. Would it be fine to continue using these or should I desolder them from the ESCās pcb and replace with something more heavy duty? (Flipsky dual)
If itās within 0,1V you should weld it in. Make sure the temperature goes back to normal. If itās not within a tenth then donāt weld it in until it is
Yes, thatās good for 120A continuous and hundreds of amperes for under ten seconds.
Just make sure if the pack can flex that the braid is set up in such a way it wonāt fray over time under heavy vibration.
Thatās approximately equivalent to three 12AWG wires.
How should i wire up my bms not sure how to set this up.
Give us a clear pic of the BMS like below so we can see the solder points. A model number and if you want to use for discharge or charge only?
Sorry about that. Its a discharge only bms from @thisguyhere http://www.esk8life.com/bestech-d140-10s-bms
Looks like a bestech D140. If thatās the case you can find the wiring diagram on the bestech side and itās a charge only bms, not a discharge bms.
Also, what happened here???
Im on phone so itās hard to make a good drawing but I think it should be like this. Someone else needs to confirm though before you power it up. Also add a fuse to the charge circuit.
Maybe to add, if it is a D140, itās ok that first pin of the jst plug is not used. Itās the balance minus and on the pcb connected with the B- thatās why itās left out.
I have 2 x D140 . On one the first pin of the jst plug is missing. Whatever you do, solder the B- first before plugging in the jst plugs.