Wait what? you’re riding 45 miles a day? Awesome!
Did we ever see the voltage cutoff parameters?
We think its 33-30V, which is fine. Whats not fine is the batt max set at 60A… that’s 120A on the battery
What voltage does the vesc show in the Realtime tab. Are you sure the battery is charged at the moment? And as @Blasto said already. You might overstressed the battery. When you have a gearing that can do 38 mph on flats and still accelerates till 48 mph downhill then your battery worked most of the time on full power and as it seems even above. Short bursts are normally fine but if you go uphill with that gearing it’s not a burst anymore. Didn’t the VESC reduce the power because of overheating or do you use the Vesc-X?
Finally it can be another issue. You could also buy a Bluetooth module and use my app to know what’s the problem. You can also try to add a USB cable to the VESC and tide it till you have the problem and then connect it directly to the PC (don’t switch the board off) and type “faults” in the terminal tab. If you see something then let us know.
yes I do lots of downhill
i set mot max and regen to 60 , -60 and batt max to 25 tried it and it cuts out even sooner and the cutoffs are 30 and 28
i guess when i get off work i will hook my laptop back up to it and try and ride it and watch for the fault code or ?
Yeah, this could really help.
Careful with that battery i think it’s a bms issue this sounds like the same issue I had
@willpark16 may have something there. The bms could be cutting out at high current demand. You could bypass the bms and run the power cables straight to the vescs for a test to see if it stops cutting out. You would see a huge spark though unless you connect it with an anti spark connector. Too bad you don’t live in San Diego, I have an extra anti spark bullet connector laying around that I used on my first build.
so I ran it with laptop connected and the fault code says undervoltage
That narrow’s it down to the battery or bms. Are you able to probe the sense cable to si if there’s a parallel pack that is significanly lower than the others?
(I’m leaning towards a battery problem)
One bad cell will bring the parallel pack down, the parallel pack will bring the whole pack down
I have to dissect the battery I mean ductape pack lol ill do right now gunna go get my board out of truck just got off work they should rename Tesla , Stresla lol
Just be very carefull, those batteries have some bite to them.
Try to keep it simple without destroying your whole build, try to access the sensor connector. (Large 11 or 10 pin connector that goes to the bms)
Before you go any farther, please tell me, how full is your battery pack when the cutting out is happening. Is it a full 42 volts or close to that?
its at 38 now but yes it cuts out on full charge
Set your max input voltage at 57V, before anything else
I did that earliar
After checking your parallel packs and if they check out ok, you might try bypassing the bms on for discharge to see if it is cutting voltage because of the high current draw.
what am I probing for im looking at bms now
I’m pretty sure that bms is only rated for 30a and thats not gonna cut it if your discharging through the bms