I care about people’s safety and if you were going around suggesting to folks they can safely jump off bridges, I’d do the same thing. It’s not “condescending”. It’s “being responsible and caring”.
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Its inadequate design and cooling of the vesc itself not a drv issue. No more debating in this post from me. Enjoy ur boards all.
It isnt, many of your posts are condescending in nature. on many threads, on many subjects. Its just your way 
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@chuttney1 What about the LM5109 drivers? 100v max. It is not integrated like the DRV so you need 3 if my memory is correct. But it works, I do have 2x VESC built with this at home. It just didn’t receive love from the community.
I think it was stated that the DRV is being run in the VESC above “safe” limits above 40v no? But a lot of people are able to run 12-13s safely with the new ones. So why not.
Yes
No
I may be more accurate :
Anybody here is able to run high voltage without safety. Then A lot of people are able to run 12s and recently 13s without reporting blown ESC during ride after many miles, which I deem safe to a certain extent.
Lots of people go to war and return unharmed. War is safe.
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There is no single answer as the data is so fuzzy, Im not surprised so many fail, esp the way you see ppl treat them.
Factors like putting them in tiny enclosures with no air rattling about and huge long supply cable not even cabled tied together are all factors that aren’t helping. Many people abuse these things.
Not to mention there seems to be a design flaw, the drv does seem to fail a lot and in a specific spot even at 10s. After studying the datasheet, i made an educated guess on what i think is causing some of the problems and added extra protection on and off chip, as have some of those manufacturing vescs.
Someone really needs to sit down with it with an oscilloscope and do some extensive testing to give you a more definitive answer.
As for 13s, that really is too close to the drv limit, as b264 stated above, you need to leave some breathing room, esp as the stock caps are all 63v and under.
Im off to bed 
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So between 10s and 12s, the heat is largely the same on the motors with it slightly higher on the wires for 10s due to the higher amp draw from a lower voltage pack? Trying not to get lost in the technical stuff lol
If that was the case wouldnt getting thicker wires mitigate the heat?
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Sophism doesn’t weight much to explain something.
My dog is 4 legged, so it’s my cat. My cat is a dog, following your statement.
Back to topic, I don’t recall blown DRV VESCs since the 6x generation. Have you? I’m not saying it is absolutely safe. Just stating that use and feedback so far show we finally have something strong enough to not fail upon use at high voltage.
Yes, I have some that failed even on 10S
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Ok now that’s something new, thanks for the info.
Look here is the truth. It doesn’t matter the series count. Over 13s you will kill escs no matter what
I think the real problem is people’s builds
- vibration dampening
- good soldering
- good covered connections
- good dust proofing
- not taping or hot gluing pinned connections in place
- using antispark switches with the wrong type of fets so when it fails it doesn’t backflow to battery and the ESC blows
- having a shitty power connection or your board is off, remote is on and you are rolling fast enough to generate bemf to power on the controller, it brakes and there’s no where for the current to go and it pops.
I think most Focbox failures are related to all the above which is basically user error.
Basically the margin for user error is high on any voltage… lol
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For the DRV8350/DRV8353, There are 3 gate drivers according to TI block diagram of this chip.
Popular Evolve, Metroboard, and Enertion commercial chargers work on your board
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Printing this on a piece of paper and sticking it to my forehead while I assemble my first build. Going 12s on my first try…
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@Jmding I think the benefit of 12S you are pointing out is this…
Suppose I am willing to accept 10S performance from a 12S battery upgrade, in other words 10S top speed and acceleration with a 12S battery pack, and to achieve this I am willing to increase my gear ratio by a factor of 1.2, and lower my motor amp limit by a factor of (1/1.2 = 0.8333), in this case the motor efficiency increases with 12S (green line, top left chart) and the motor heating decreases with 12S (purple line, top middle chart), while acceleration between the 2 systems is identical (yellow line, bottom left chart - vehicle thrust in pounds), and the top speed is nearly identical (yellow line, bottom left chart - vehicle thrust in pounds).
Still there is no bonus 20% wheel torque with this arrangement, only greater efficiency.
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until you hit a tiny bump at the exact right time in the cycle to send a voltage spike through the line and burn up your DRV chip, throwing your face at the street
“but internet guy said he did it and was fine…”
We can talk theory all day, but something that works 80% as good at the extreme ends of the operating conditions and similarly good through the rest of the more normal conditions, but with a smaller failure rate, is clearly better.
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Wow… Why do theory discussions always get so heated? It seems like there is a body of evidence that suggests 12s+ likely leads to premature failure. Being a forum community, we don’t have great data to confirm this, but between the 60V nominal rating being very close to 12s voltages and the empirical evidence, going beyond 10s should be considered “at your own risk”. We can all agree on that I think?
So then we should know what the reliability / safety trade off is. Which I contend is still 20 percent more torque (assuming you gear to the same top speed)
Prof, yes the benefit is because of the 1.2x change in gearing. I don’t see why you don’t have more torque though. Both setups have the same Kt and current. But the 12s setup has more gearing. Therefore more torque no? Said another way, the 12s setup is capable of more electrical wattage AND more efficiency, so it must be capable of more mechanical wattage?
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I shit ye not, whilst i was reading this line of text my inner voice morphed into Venoms voice.
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