Vesc brakes help

Battery cut off should not be 42v. 33/30 is a good figure for li-ion 18650 cells, but I use 30/27 myself. If you’re running lipo 37/35 is a good number

while i was riding today i saw that the board was accelerating and when i stop accelerating the board will kinda break … is this normal ? (i guess)

ye i have 10s4p li-ion 18650. so i have 42v from the battery. why would i have max voltage at 57 if my battery can give max 42V and why the cutoff that low at 30 is kinda out of juice

Are you sure that wasn’t just because of the drag of the motors/belt that you felt like it “braked”?

Because if you go over the value you put in there the VESC turns off and errors out. You can get voltage spikes from braking so it’s wise to leave it at default 57v. There’s no benefit to changing this at all.

30v is a bit low but a 10s pack can go as low as 25v. If I’m miles out from home and my batteries are low, i’d still want them to be able to take me back. That said, I try to never go below 3.4v/cell on my pack.

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So this should be a better configuration right ??

Or should i keep the batmax and bat min to 25A/-12A. Hmm honestly i have no idea why are they so low… in all other examples pll usually used same value for motor max bat max and same value for motor min and bat min .

What values would you recommend ?

Honestly I would use @Ackmaniac’s f/w instead of stock for better throttle control

For current limits yours are okay, but you’re battery min is too high, a 10s4p setup can take -16A regen current, though you’ll regen so little it probably doesn’t make a difference even if it were a little higher. I usually keep my motor min 10 amps less than my motor max too. In this case -50A.

Hey guys thank for help. I’ve done some more testings today indoor and i still have some things unclear.

Here are my latest settings. Hopefully this time they are ok.

My problem:

  1. When i move the throttle just a little bit it will start accelerating and continue till it goes to max… so im getting to max with just a little bit of throttle … After it gets to max i tried to push it further but no change in rpm or in sound… so thats how i knew it was at max… a) i did calibrate the remote before i turn my board on b) i did the setup with min/max pulsewidth from bldc tool

am i missing something ??

  1. i watched the real time data graph from bldc tool and when i break again no matter how hard it will get full breaks on me… is this normal ? shouldn.t it be in steps depending on how hard i move the throttle ??

Thank you.

Remember also to change your min / max Erpm to 60.000. With a dead / defective DRV chip, you also get weird behaviour

ok now i hae the erpm to 60.000 but still the same behavior … im pushing the throttle really slow to the first position where the motor starts spinning and it will start accelerating to the max … i was on the realtime data that my erpm it going to 52.000 …

honestly im expecting it to accelerate when im pushing the throttle more not accelerate on it.s own ?? am i wrong ?

I think there should be seperate tab to see what, your remote does (what signal vesc receives)

So if u can u might as well check that, though.im still an outsider with vesc, but that is what i would look for.

I think you’re referring to the display window in a few of the Application tabs (PPM in this case). Here:

@Bloop It looks like the checkbox next to “Display” in this screen shot is unchecked here. I didn’t see any comment indicating you’d done much with that box, so can you check it (click it) and do a test (maybe take a video and upload it to youtube or something so we can see it) of that bar when you’re slowing going from the middle of the throttle, up to the top, back to the middle, and then the same to the bottom?

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Yep, this is to what I was refering to :wink: @rpn314

I wasnt sure he knows about it, so I thought it is a good idea to take a look at it.

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i did check that forgot to update the picture. Here are my new values.

I will make a video shortly so show what i mean …

That’s fine. I wasn’t worried about the screen shot, just wanted the video to try and help :slight_smile: Checking it doesn’t change anything on the VESC; it just displays that info in BLDC tool. It’s quite useful for issues like this. Awaiting your video :nerd: :popcorn:

Does your motor have hall sensors? It say that hall sensor detection failed. Run the detection again and do the read/write configuration and reboot.

I’m surprised no one mentioned that this is expected behavior. Current control mode will always ramp up to full speed of it overcomes load. Bench testing will always get you max speed at low throttle since there’s virtually no load. Same for braking. You’ll see much different behavior when you actually ride the board, but the speed will still not be throttle dependent.

Remember, the throttle controls acceleration, not speed.

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i have no sensor

oh i see now. well so even when i will ride it . it will eventually accelerate to max even if im only pushing a little on throttle ??

is there a better more so it will maintain my speed unless i push further the throttle ??

It depends on load, if you only push a little bit while you’re on the board it will probably maintain a slow speed because the current supplied isn’t enough to overcome load.

there are modes where throttle position determines speed (duty cycle/pod control), but it also means when you let go to neutral it will brake and slow down since you’re technically moving the throttle back to resting position (complete stop)

Current control is the “better” mode, you just have to get used to it

when i tested the current control i had trouble breaking … but yeah i guess if i get used with it will be fine. i will do some more testings tonight and come back with updates. thank you .