You’ll need to post screenshots or values of all your motor/power settings
Drop your battery current max to lower than your motor current.
99 battery amps per motor is default vesc value unwittingly designed to kill you
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Do you think that’s why my board is cutting out though? I’ll fix it but just wondering.
Yeah, those default values probably aren’t safe to run. Hopefully nothing was damaged during the limited testing.
I learned how to program my ESCs using the MBoards tutorials. Don’t follow the values to a T, but they go over the important numbers you need to know about.
Don’t think that this is the problem. You need a logger to see what’s going on. Was it a complete cut out, like the board shut off? Or was it a remote(flipsky vx2) cut out? Is your battery 12s?
It’s a 12s4p P26A cells
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I’m pretty sure it was a full cut out. I did a little test today trying to re create the problem but nothing happened. I was pulling about 8 amps and I only sagged about 1-2v. I did have a little bug happen. I don’t think it affects anything but when my board is standing completely still and I apply brakes my remote starts saying random things. It was saying I was riding at 60mph, an odometer of 9999 miles, battery completely dead, connection lost to my receiver, and the list goes on.
I followed the guide but I’m still getting some weird issues. I posted about video showing itz
What did you decide on for battery current and regen? I agree that the default values probably aren’t causing the issue, but those are still important settings to understand.
I would start by replacing the remote or taking a close look at the wiring. I noticed electrical tape on a few parts of the build—is there anything similar going on around the receiver?
Battery current I did 50a a side then for regen I did -10a a side. The reciver is just taped down on top of the bms. I could move it though.
Those numbers sound reasonable to me! Although I did not consider any of your battery specs.
When I mentioned the tape, I meant that it looked like you might be using electrical tape to splice some wires together, but now that I look closer, that might be proper heat shrink, anyway.
I was wondering if your remote harness has any splices and, if so, how you connected them.
It seems like a weak joint could potentially cause buggy behavior like that.
I haven’t cut anything on the reciver harness except switching the rx and tx pins to make it vesc 6 compatible.
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Molicel p26a suggests an older battery.
4P of a new healthy p26a would be a nominal 35 amp max per cell temp limited or 25 amps without temp limit, but inside layers of fishpaper and kapton inside a dead air enclosure this needs to be reduced further.
Your 50 battery amps per motor are at the far upper limits of this cell, when it was new.
Your cutouts might be from excessive voltage sag.
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that joint is soldered together than I put electrical tape on top because I keep forgetting to put heat shrink before I start soldering.
Oh gotcha
I think @SternWake is on to something. Would be an easy test.
Only if the bms was wired for discharge or the battery level was quite low to begin with.
I’d be setting battery amps around 30a per motor and regen amps at least -20a. -10a seems like it might be a bit weak
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When I was looking at the spec sheet for my the p26a I saw that the max discharge amperage was 35a. So I did 35x4 which is 140 the divided that by 2 to get 70 and took off a bit more for head room. Same thing with regen, max charge is 6a per cell so 6x4 is 24, 24/2 is 12 and even a little more headroom for -10a each side. Correct me if my math is wrong or I’m doing something wrong please. Just watched the mboards video on how to program these. Here’s the spec sheet
I just rode 6 miles without any failures after switching some values last night. Not sure if it was just a fluke yesterday or not.
So it has been stable since setting batterys amps and regen?