Brakes release/cut out

Searching this forum and can’t find a fix for this basically when I brake the brakes release and I have nothing! Happens at high and low speed and upon inspection the vesc is flashing pink when this dropout ocurs. I’m using the mastercho mod for the gt2b and my vesc is v4.12 from diy.com I did come across a thread from 7 months ago with people with the same problem @chaka @FLATLINEcustoms did you ever find a fix for this I’m using ppm,current no reverse with brake,bldc

What’s your maximum input voltage set to on the bldc tool?

Did you try the gt2b before the mod and did you still have this problem? I had issue when adding enclosure because it allows to much brake trigger movement that the vesc can’t register it.

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Can you post some picture and bldc tool screen of your setting ?

Yeah had a feeling it might be this or the band pulse width will try fix the brake length on the gt2b mod first. seen someone use a bit of foam,failin that I’ll upload my bldc readings tomorrow

@MasterCho had anyone else with this problem does it alow more brake movement in the trigger?

I have the same problem.

DIY VESC Single 190 kv 3150 watt motor 12S1P Lipo (20c) 5000mAh

Here is a log of a recent run

At 50 - 75% brake, the regenerative current gets to high and as a result it stops braking. This gives really dangerous situations. The max braking current is set at -12A, but as you can see above at 7:31:39 PM at about -3A it stops braking as a result of over current.

Here are my settings.

(detection of motor was OK)

(did not change anything here)

(Receiver gets to 99,9% at ful throttle and 0% at full brake)

Just use my firmware mod. There you can use the full throttle range of the acceleration and the brake by setting a center position.

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Here is a pick of gt2b and look how the case limits the brake travel

with a enclosure mod badwolf and madmunkey, idk about others there is nothing stopping it This is with madmunkey (still need to fix since I just made switch from badwolf). If you change pulsewidth without limiting trigger to like .7 and 1.9 you CANNOT set failsafe properly. when you limit trigger it will be closer to 1 and 2 and you’ll be able to set failsafe at exactly 50%. I always assumed it was over voltage but it was not

Interesting @Titoxd10001 I will connect a gt2b later see if that eliminates it! Like @Cuprani said it creates some dangerous situations and we all need to find the cause asap. @Ackmaniac thanks man where can I find your firmware upgrade

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Your firmware upgrade is on my to-do list, but besides cutting out, having all that extra brake travel is uncomfortable on the trigger finger. Also the cutting out problem happens in car ESCs so it might be beneficial to have a physical stop

Here you can find my firmware mod

And you could also change the throttle curve for braking to have a full brake already at like 70% brake throttle. And you could fine tune the throttle curve by a Android app to find the sweet spot on the road. Problem in the firmware is that when the pulsewitdth signal is more then 20% away from the full brake position then the VESC thinks it’s a problem with the signal.

e.g. max pulsewith = 2.00 min pulsewith = 1.00 so theoretical center is 1.5 (in my mod you can adjust the precise center) when the pulsewith is now at 0.91 it thinks it’s already a full brake but excepts it. (18% off) when the pulsewith is now at 0.79 it thinks it’s to far off and something must be wrong. (22% off)

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With your firmware this situation is avoided ?

Not really. But you can adjust min, max and center position. So you can use the full throttle range for both directions. And you can adjust the throttle curve to your needs.

And by this the problem doesn’t exist in my firmware mod.

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After browsing through a similar thread about the same topic I found this from @dogeatgod

seems restricting the brake trigger movement on the moded gt2b and changing pulse width should work! Been too busy today to pull the board apart but will try it tomorrow and report back.

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@Cuprani @Kaly check this out think it’s a software bug,also take the poll.

[POLL] Do you have braking loss? Even on BLDC? - General Discussion - Electric Skateboard Builders Forum | Learn How to Build your own E-board

I’ve filled in the poll. Tonight I didn’t turn off my board for a change (I usually forget to leave it on when the brake error have occured). I logged the following fault and this was during braking.

The following faults were registered since start: Fault : FAULT_CODE_ABS_OVER_CURRENT Current : 47.0 Current filtered : 100.9 Voltage : 49.08 Duty : 0.00 RPM : 2248.6 Tacho : 694719 Cycles running : 16227 TIM duty : 263 TIM val samp : 131 TIM current samp : 26505 TIM top : 52747 Comm step : 3 Temperature : 43.77

Vesc 4.12 with stock 2.18 firmware 36T on 90mm wheel 16T on 190kv motor (3300 watt) 85 kg

your abs max current may be set a little low, is it at 130A? you’re running a 12S setup?

Because I had a lot of heat I just lowered it today to 100A. I’m running 12S and it was on 130A before.

If this caused the fault I will change it back to 130A

the abs max current is a safety feature, this is the current where the vesc will shutdown beyond this current threshold.

For example: one of your windings in your motor shorts out, you will most likely hit this threshold.

If you want to lower your generated heat, you need to lower your batt current.