Fault : FAULT_CODE_OVER_VOLTAGE
Current : -14.2
Current filtered : -14.3
Voltage : 57.35
Duty : 0.27
RPM : 21833.1
Tacho : 453339
Cycles running : 10841
TIM duty : 3498
TIM val samp : 1748
TIM current samp : 8175
TIM top : 12854
Comm step : 5
Temperature : 48.62
Fault : FAULT_CODE_OVER_VOLTAGE
Current : -20.3
Current filtered : -15.9
Voltage : 57.41
Duty : 0.20
RPM : 17775.2
Tacho : 464138
Cycles running : 4798
TIM duty : 3221
TIM val samp : 1610
TIM current samp : 9744
TIM top : 16268
Comm step : 2
Temperature : 46.49
Fault : FAULT_CODE_OVER_VOLTAGE
Current : -11.4
Current filtered : -11.5
Voltage : 57.45
Duty : 0.23
RPM : 17776.1
Tacho : 486449
Cycles running : 6651
TIM duty : 3358
TIM val samp : 1677
TIM current samp : 8969
TIM top : 14583
Comm step : 3
Temperature : 47.65
Fault : FAULT_CODE_OVER_VOLTAGE
Current : -23.3
Current filtered : -16.5
Voltage : 57.63
Duty : 0.14
RPM : 14073.5
Tacho : 505408
Cycles running : 4414
TIM duty : 2848
TIM val samp : 1426
TIM current samp : 11865
TIM top : 20877
Comm step : 2
Temperature : 48.48
Fault : FAULT_CODE_OVER_VOLTAGE
Current : -34.5
Current filtered : -22.3
Voltage : 57.68
Duty : 0.10
RPM : 11553.5
Tacho : 522941
Cycles running : 3915
TIM duty : 2513
TIM val samp : 1264
TIM current samp : 13767
TIM top : 25007
Comm step : 1
Temperature : 51.99
Decreased battery min (regen) from -8.00 to -5.00A
VESC still cutted out but a little less frecuently
Brakes were sluggish
Decreased battery min (regen) to -2.00A
Brakes force was almost non existent
VESC didnât cut out once
Increased Maximum input voltage from 57V to 58V
VESC cutted out at 58.7V (same problem, more voltage, less safe)
Reduced Motor min (regen) from -60.00A to -30.00A
Same issue, no change on feeling of the board on braking, VESC still cutted out
Iâm out of ideas on what to test next, what would you guys suggest in order to avoid this that wonât be charging the board at 89%, do you think it could have something to do with the small motor pulley?
The culprit was the BMS, it was cutting regen supply from the motors during braking in order to protect the battery to be charged more than 42V, nevertheless the motors kept spinning, hence braking and regenerating and the flow of current had nowhere to go, so it was being stored in the VESC raising the voltage until overcharge fault was thrown.
I changed this wiring:
BMS for charge and discharge
Hey there, Ive been worrying about this exact problem for a while now. I dont see how this solves the problem (although Iâm happy for you that it has)
as far as I know, The issue is that when the battery is full and you brake, the VESC cannot dump any current into the cells, because the BMS tells the vesc that the cells are full.
Then the VESC is shutting down to protect itself.
Is what you have done the following:
When charging via regular wall charger, the charge goes through the BMS, this means that at a full charge, your cells are sitting at a nice happy 4.2 V
BUT when you brake with your motors, they send current straight to the cells, bypassing the BMS, so the cells may get to 42.1 V or something, but at least nothing shuts down.
Does the BMS not freak out at that point, telling the vesc that thereâs the problem (I keep thinking of a skateboard as a community talking to each other so that I can shred the streets)
Is the general answer to this, to under charge slightly, maybe 0.5v? Your brakes then work even right off the charger, and you get more cycle life for your cells by 1. not overcharging during braking, 2. not charging to max
@PXSS Iâll set a fuse between the battery and VESCs, unfortunately there no much space and the 80A fuse and fuse holder are extremely big.
Has anyone found a small and suitable fuse and holder for this application?
@deucesdown, if you check the charge on each cell the voltage at full charge sits between 41.6-41.00V so charging a little bit more wonât cause any issues, some people charge it until 42.5V or even 43V, cell wonât be automatically damaged, on the other hand this will be donr only for a fraction of time, Iâd say between 1 and 2 minutes of riding.
Isnât the maximum input voltage setting on the BLDC tool supposed to stop this?
I know a lot of people say to leave it at 57V to stop the vesc switching off but if youâre discharging without a BMS shouldnât this setting stop you overcharging the battery?
Not really. That setting is meant to protect the VESC from over voltage and not the battery. Setting it at 42V would only cause the vesc to shut off sooner.
2 options are set to 57v and slightly overcharge when braking or set it to 42v and not overcharge but shut off when braking
Wonât even happen for that long. Itâll literally only happen while you are actively braking enough to charge the pack above 42v. As soon as you stop braking, the voltage should settle back down.
Donât want to start a new thread as this seems to be similar to what I experienced today, but could you guys check my error log and see if this would in fact be the same issue as @Eboosted experienced?
Not sure when I received this error code as board was on for several hours, but at the beginning of the ride with full batt. I had several losses of brakes when going down a very very minor slope at almost zero speed⌠Had those brake cutouts a few times and avoided to go downhill and no more brake issues since.
