Hi - I am struggling with an DRV8302 Under Voltage error. This is my first build and the first days riding around the neighborhood everything worked nice. The single motor has impressive powers - more than my expectations.
I finished the enclosure and put everything together. After mounting the enclosure the board suddenly stopped while hitting the power - something I hadn't experienced earlier as far as I can recall (I think I hit full power the first days a couple of times). Today I got the metr.at dongle and reproduced the error while recording. The error I got was "Under voltage" and "DRC8302". It happens whenever I am pushing more watts. When the error occurs the VESC normally shuts down and I need to restart my board - then it works fine again. On some occations I react fast and break as soon as I notice the voltage drop and then the VESC stays on I can continue riding. You see a lot of these small voltage drops in the log.
Some background info:
- See my build thread: http://www.electric-skateboard.builders/t/portable-custom-birch-fiber-gl...
- 10s3p LiIon with LG HG2 batteries
- 190 KV enertion r-spec pro motor
- 15-36 pulleys
- VESC 6 beta
- My drive log: https://metr.at/r/KX1ng
- VESC-Tool Motor settings: https://www.dropbox.com/s/1usvf12bqc9b8io/Skjermbilde%202017-09-01%2020....
- VESC-Tool FOC settings: https://www.dropbox.com/s/mdyz3ooikcqv150/Skjermbilde%202017-09-01%2020....
- VESC-Tool PPM settings: https://www.dropbox.com/s/10rbahky2alqrrl/Skjermbilde%202017-09-01%2020....
- BMS configuration: https://www.dropbox.com/s/9kvxxaluf6n2t94/Skjermbilde%202017-09-01%2020....
- You can see the errors clearly in the log. At least at about these timestamps: 19:23:58, 19:39:47, 19:43:17, 20:04:31.
What could be wrong? Is it a short? Or is it the setup? Is the BMS funky? Why does it work immidiatly afterwards/aftere a reboot?
Obs! When the problem first occured I had different VESC-Tool motor controller settings:
https://www.dropbox.com/s/sykoecdbjsii98q/Skjermbilde%202017-09-01%2021....
The motor controller settings in the last post were used for the recorded drive (metr.at log).
I am not sure what is going on, but the board seems to perform well other than the hickups that come occassionally. It seems that the voltage drops to at least half of the battery pack capacity. The BMS I use has a soft switch. I suspect that it turns itself off for some reason. Maybe a short on the BMS board something, I am not sure. I guess the next step will be to unwrap the BMS for some investigation and double check the soldering and connectors.
I cannot find a pattern and the drive log: https://metr.at/r/ovk1x But my experience is that it onyl happens while giving quite some throttle. When I carefully accelerated up a hill it went well but accelerating fast -> Under Voltage.
As far as I can tell it looks like the BMS cuts the power for some reason. In both your rides the battery current seems to stay below 14A if the log is correct.