Not necessarily. Free roll on direct drives or hubs is pretty awesome when rolling downhill.
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Yup fair point. For clarity my board I was referring to was on gear drives and pneumatics.
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Welp you’re gonna overvoltage by overspeeding if you step above your max erpm, that’s dependant on your voltage and Kv tho?
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Thats what I thought but didn’t wanna say cos I’m more of a ‘send it and see’ kinda guy 
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Probably not very practical but a fun idea: EDF with RC ESCs can consume a stupid amount of energy in a pretty small space. You could mount a EDF on the nose of the board and use it to drain the battery when its full while also helping to break a bit.
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?
Electric ducted fans. Used for RC aircraft.
It would have the advantage of not creating stupid amounts of heat and actually help a bit with breaking.
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I love it. Fully on board.
Flyback capacitor and resistors with a heatsink outside of the enclosure
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Sag of doom?
Once the phase voltage is a certain value above the pack voltage (that I have no idea how to calculate) the FETs will start to conduct and dump the current to the pack, you wanting it or not, never wanted to test in real life but I never let me board go above the max speed it can do powered
As far as I know this is the main problem with field weakening, while it is active it can control this and make the voltage be lower than the pack, but if the vesc fails for some reason it would brake with a lot of force suddenly
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Then we can monitor overvoltage and instead pull high current toward big resistors via a mosfet? Overvoltage triggered = full Mosfet turn on?
Actually it could forcefully redirect part of the current with a pair of mosfets switching ON/Off
Btw There was a guy who made few years ago a system for his euc with leds, it was bulky but he was dissipating enough to stay within his limits (somehow the battery seemed to still be able to mitigate part of the watts to he needed to dissipate only 200-300w) I might still have his schematics but not sure the video is online
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Here is the inside of the Maytech rheostatic breaking system. Looks like all the internals are, is 2 100W 20 ohm resistors, and a small PCB to control it. Testing shows it’s triggering at 52V and the resistor gets hot fast at 2.5 amps. Probably will burn up pretty quickly.
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how on earth did he stay balanced while that was eating up braking current?
It really was smooth, only the excessive watts/voltage was redirected so you weren’t seeing any balancing difference from him (however looking at the real time data log, without his brake chopper he lost braking ability few times DH so he had to freeroll)
Thanks!
LOL…”100W” resistors. Those might, maybe, perhaps be 25W resistors and that style of resistor can only meet their rating if they are thermally coupled well to a large heat sink. In that box those are 5W-10W resistors, at best. 
They can still do the job if the power levels aren’t too high and the durations are short.
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Excellent, thank you for that link.
Halogens! (running joke)
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Weeell 
He miiight maybe, just maybe, have mounted fat halogen bulbs with a massive heatsink on the side of his EUC… “It looks cool” he might have said… cough
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I was under the impression that freerolling on an EUC was not in the realm of human capabilities
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