FW 5.2 and setting duty cycle current limit start to 85% or less (on both sides of the ESC) is a safe bet, and might fix the issue you’re having.
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Could it be motor temperature limits being hit?
I had higher motor/vesc temperatures on my ride and had no faults recorded. I know the spots where I got the wobbles and checked with the logs, the temps were lower than some other parts of my rides, eg hills.
I will give FW 5.2 a shot these days.
Any chance you’re running a Flipsky A/S?
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Xenith v1 + bioboards 6374
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You could also directly go to FW5.3, so far works really well on Xenith.
Update: duty cycle current is not the culprit, I did more testing and found out that this wobble occured when motors get hot (70+ Celsius). Throttle limit for temp is at 80 but one of the motor acts up when hitting that temperature.
I want to try BLDC mode but vesc app ios won’t let me change from FOC, will try it on PC
It looks you were right, shouldn’t be both motors limited at the same time tho?
Nein - each motor can hit its own limit independently I think.
Not sure though, happy for someone else to weigh in on this.
Temperature cutout can start from one motor at a time but shouldn’t both motors get throttled so jitter would be avoided? On the steepest hill I get 90C on each motor, are these temps acceptable?
what are you checking motor temps with? do you have something recording telemetry so you can zoom in and look for noise. ( rapid jumps in readings)
motor temperature sensor noise, can cause this.
usually it causes faults, but not always, sometimes it just jumps into the temp throttling zone, and back out. sometimes it jumps far enough to trigger a fault.
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I am using stormcore app but it’s not good at checking for spikes. Mettr is not detecting my Xenith, ios and android.
I will record tomorrow on Yours Truly app.
From my testing the wobbles occur when hitting the throttle limit, I set it to 70C and it occured, then at 90C and same results. I don’t think it’s interference, I am pushing the motors really hard to find what’s causing them, huge hills and 35C weather gets me 90C motor temp. No faults were shown on Stormocore app.
I am running FW 5.2 on Xenith V1 with dual bioboards motors 6374 on gear drives.
I will be testing traction control ON to see if it helps.
I wouldn’t throw that variable into the mix.
it won’t cover up an issue well. and it’s not a real fix.
it has it’s own tunings (erpm difference) to get used to.
Ok, thanks for the input. I don’t really know what I can do so far when hitting the limit, highering it might fry my motors but I also don’t want do limit my board by lowering amps.
Do you think BLDC might help? From what I’ve read FOC is more efficient. Also my motors don’t want to be detected in BLDC so there’s that
funky behavior near top end in my experience has been…
a.) temp sensor noise.
b.) duty cycle current limit start too high
for a) in ideal senario, power just gets slowly limited starting at motor temp cutoff start, down to motor temp cutoff end at which point it throws a fault. so if that were workign right, no funky behavior.
with noise… you get random amounts of throttling, and random faults.
if you have noise. give up on temp sensors is a common option. also a decent test, you can try to depin the temp sensor wire and see if the problem goes away.
for b.) it just ramps down current starting at duty cycle current limit start until max duty cycle, which prevents an abupt loss of power when hitting max duty cycle. so make sure it’s set to like 85% and don’t mess with it unless you feel you can tell and you need to tune it closer.
i don’t know if BLDC would do anything or not… but i suspect not.
I suspected the duty cycle bug but it wasn’t the case. It was set at 0.9 duty cycle current. After changing to .85 same results. Riding full speed at the begging, the board was acting ok at 50km/h. After some hills and increased motor temp the jerkiness started when full throttle. I will test the board with only one motor sensor
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You can just unpinn the temp sensors from the sensor jst to test. Almost always its the white wire.
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Deff no expert but what if they weren’t the same kv (even if stated on motor it’s the same)? Have you checked that out if nothing else works?
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Haven’t checked it. They are identical. Both get heated up at same temps from what I can see in the app