How bad are DRV errors really?

People keep getting their ESCs fried from DRV chips getting blown or getting in bad crashes from DRV faults, but like what are they? And will I die from getting all of these? My other board gave me errors without issue all the time too

10s2p 30Q (30A/-20A)
MayTech 4.12 w/ TB Nano
Single Racerstar 5065 (30A/-20A)
13:36 76mm

You’re basically already dead. That’s a Texas sized 10-4 (I hope you enjoyed this and get the reference)

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I wish I understood the reference, I’m still an uncultured child

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But like am I actually at risk of injury here and how do I stop it?

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Its a pure gamble. But they’re more prone to happen at big brake/throttle changes. The IC is designed for a specific max voltage. Where sadly a ton of factors come to play weather it gets fried or not. Just such a thing as batch nr on the IC could play a role to sensitivity. Guessing you’re using a 4.x HW version and would recommend steping down to 10s if you’re currently on 12s ( lika alot of people are).

*Edit, nvm saw you wrote 10s, my bad. Maybe time for a esc upgrade?

Every time it’s during 1 to 7 amps of braking, never during acceleration, both ESCs are brand new

If I just threw away $340 I’m gonna cry

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I mean most of the time the vesc ceases to work when it gets a DRV from my experience, unsure how yours is still chugging along. Imo its a ticking time bomb and inevitably it will die and probably throw you off the board

Did you try to do FOC by chance

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So what do I do about it? Both ESCs did it right off the bat

I’ve always ran FOC, this one is sensored and the dual FSESC 6.6 plus is currently running sensorless FOC

Hm yeah idk you can’t really do much about it, I think the IC actually gets damaged on a drv error.

I have heard FOC is much harder to run on the components but maybe the FSESC 6.6 can do it fine. Idk about Maytech though

I got a drv on a TB Vesc years ago and had to send it to drv wizard to fix

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Well shit, good thing I usually don’t go that fast so tumbles are not too bad

Someone else might share a different opinion than what I expressed, but yeah wear gear haha

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:sweat_smile: Anyone got a LazyRolling hoodie that’s too small for them?

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My theory is the gate drive power supply is a linear regulator, which is very inefficient at 10s and up. It takes a lot of power to drive those big power fets on the vesc 4 at 40khz, so it overheats and either thermal shutdown or smokes out…

Vesc6 seems to have much less issues, as it is happy switching at half the speed. Imo this is a small weakness in the vesc design.

You probably need a new one so pitter patter…

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So how can I get more life time out of this one? Max the throttle all the time so it’s full switching or no switching?

The VESC software is written in such a way as it never really gets to “no switching”. VESC is not popular in airplanes for this reason.

To clarify: you have a (probably) busted 4.12 and a functioning FSESC 6.6 on a different board?

I suspect the best thing to do is slow down the switching speed. I run 20kHz in FOC mode on the same flipsky dual 6.6 you have and it seems to be fine, though I haven’t actually loaded it very hard or looked at it on the thermal camera under load. The reason vesc 4.12 needs to switch faster than the 6 is that it has cheaper sensing circuitry, so it needs to switch faster to get enough data to keep track of the rotor.

I wonder has anyone ever experimented with putting a little IC cooler on top of the DRV chips?
image

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So if I drop switching to 20kHz I might get some use out of it?

My experience is when you see DRV faults start happening, they will only become more frequent until the ESC dies. I have never seen a DRV fault on an ESC that didn’t die soon afterward. I’m sorry for the bad news. Hopefully yours doesn’t die.

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Fuuuuuuuuck

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