Not with 21s
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it only takes up to 18s
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Ah gotcha for some reason i was thinking 22s hah
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AFAIK only the Ubox 100v has a claimed rating at 22s, and that comes with a caveat that you must not have voltage spikes above 93v, and none of us really know what the safety line for voltage spikes is. I believe @poastoast has seen up to 8v spikes, and he’s on 20s? Poast, what kind regen do you run? anything you do to lessen spikes?
I believe 25% headroom is the generally accepted reliably safe headroom according to people on the VESC discord, but this is perhaps overly conservative, as there are a good number of people running 20s on hardware that doesn’t afford that 25% headroom.
When you push voltage and current higher, weird things starts to happen. My take is if you want anything above 20s, it’s a proceed with caution deal.
Credit to @jaykup - half of this post is just relaying info I have heard from him at one time or another.
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I still have a ways to go before I fully understand all this stuff, but the only thing I’d add to this is that voltage spikes don’t just happen from regen. There is a lot that goes on microsecond to microsecond that the VESC logs don’t capture.
Running these things under full load while scoping several areas of the ESC is really the only way to know for sure what the limits are. The DC bus voltage ripple may be within acceptable range, only for the mosfet gate ringing to exceed the 20v spec and kill the mosfets anyway. All this changes as the voltage and current levels change. PCB layout choices, proper component selection in things like the snubber circuit or any number of other factors can make the difference between a controller that works or dies at 22s using 100v components.
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i run 50A per side
i’d say lessening spikes can be aided with a longer ramp time, higher p count, or just don’t be as aggressive on the brakes like i am at the start 
we could also try to design a spike absorber with, say 90V TVS diodes on the battery leads
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wouldn’t something like a rheostatic brake module also help by just dumping the energy into heat instead of forcing it to go back into the system?
that could work too, but it lowers our efficiency
getting some regen is nice
I mean if youre running crazy voltages and pushing stuff to the limit im assuming efficiency is pretty far down the list of priorities, probably after “not blowing up your esc”
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but that’s what i’m here for!
blowing shit up 
The “no update, update” here.
Started off 2023 by hitting eject on life and moving into my campervan. No workshop means nowhere to build, and I decided this board was never going to get done if I didn’t tap out and call for professional help.
@Skyart has the deck, enclosure, and all the electronics. More updates to come in a month or two I hope 
I’m currently in San Diego and I have my lacroix down here. @ShutterShock @KaramQ when are we riding boys? You can let all the SD ladies know that the shoulder model is in town.
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Lol how long are you here? You didn’t reply to my message in the chat a few days ago
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Yeah that was my bad. I’m around for another two and a half weeks. I could ride Sunday maybe or any weekday after 5pm, except this Friday.
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Uuuuuum these are some mighty fine parts here…
Alex already screwed up the battery config once, let’s see how he does on round 2 
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Evan has requested all hot dremel action on this build be live streamed to him.
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Bout to cut that enclosure, try out my new “precision”tool
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Wooot. Jelly to see this get built up. I envy redembers
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@Shadowfax ,so your finished board can sleep in my garage,ill cover it with a blanket,ill even ride it so it doesnt get lonley 
my giant dog will protect it from raccoons
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UPDATES BABEH
I visited the @Skyart workshop while driving back from Canada. @poastoast finished off the battery last week, and the man himself put the finishing touches on the electronics while I perused the shop for extra parts.
Welcome to my makeshift workshop
Lil foccers for a lot of voltage and amps.
Hand filing the enclosure for phase openings.
Fitting the gasket
3 link setup.
I polished some flipskys. These are going up for sale actually.
Meepo tubeless on newbee pentagrams. Fit is perfect.
Fit check on motor upgrades
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