The motor acts like a generator, generating 40 amps. The controller takes that 40 amps (at low voltage) and converts it to 10 amps at battery voltage.
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So there isnāt a reverse signal being fed to the motor from the battery at -40A? Does the extra 30A get dispersed through the VESC?
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Also just for further clarification, the motor isnāt just generating 40A though right? Itās up to whatever the speed is at the time so it could be +/- 40A. Does the 40A means the VESC is only willing to accept 40A from the motor?
To answer your first question, no there isnāt any signal coming from the battery, just whatever voltage your battery puts out. When braking, the vesc is actually putting energy back into the battery.
to answer your second, BLDC motors always act as generators when spinning if not being fed power from the vesc. The vesc can control how much of that generated power it accepts (up to 40A in this case) and passes on to the battery.
If the motor was connected to nothing, then it wouldnāt be generating any current, but it would still be producing a voltage. If you were to short out the three phase wires, then it would generate a LOT of current, because it would be feeding into a dead short. The vesc can control the effective āresistanceā the motor sees (and thus how much current the motor will produce) continuously to stay under that 40A cap.
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Ahhh I had always assumed that there would be a reverse signal coming from the VESC. I know itās possible to do so but I guess standard programming of the VESC is purely brake and no reverse.
Thanks!
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Thatās the basis of this
I think if you connect a brushed DC motor to the VESC, it might do that. Iām not sure. With a BLDC (3 phase AC) motor though it acts as @MysticalDork described.
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If you set your vesc to do reverse, it will behave as I described above as long as itās going forward, and then switch back to treating the motor as a motor again but with reversed rotation once it crosses the point of zero speed. Long story short, thereās a LOT of complicated math, measurement, timing and guesstimation that the vesc has to do to ājust workā.
With either a brushed or brushless motor braking at low speed, you can feed battery power back to it in reverse to increase the braking strength even more - the maximum braking capability of the motor is not the same at all speeds, and especially in brushed DC motors it falls off sharply at low speed, for reasons that are too complicated to explain here. Your motor min and battery min (regen min) settings affect this significantly.
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I got a downill 36" board with 52 holes drilled, my own + the predrilled ones. i i was thinking when is a deck unsave when riding 25 Mph+?
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Depends entirely on the size+placement of said holes. Need more info before we can tell you anything.
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Does the can bus port use jst-ph 2.0mm pitch connector? Iām trying to make some but not sure if it uses the above.
Yeah, all the ports on a vesc (at least the vescs Iāve used) are PH 2.0mm.
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Heat. All those lovely amps are heat. simply put.
My favorit thread 
I have 10s3p 30Q pack 9Ah
i got a 42v 2a Charger how long to charge it from 0 - 100%
9ah / 2a = 4.5 so 4.5 hours or how do u calculate?
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Thatās about right.
It tapers a little at the end, so maybe a little more time.
Batteries wear out, so maybe a little less time.
But the biggest difference is that I rarely completely discharge a battery so itās usually a lot less than that.
Yeah iām avoiding that. Tack 4 the quick help Btw.
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I fully subscribe to @b264ās all boards fully charged whenever possible philosophy. The few times I didnāt use this approach I regretted it. I donāt care if itās the wrong plan for longevity.
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I only leave a board uncharged if itās broken. Then I still always regret it because when I fix it, I have to wait for it to charge. But it seems silly to me to charge it, if itās broken. The batteries would prefer not to be fully charged, and I know itās not going to be riddenā¦so I leave it in the 50%-75% full zone
How does one calculate peak discharge of their packs? I made a 10s6p out of molicel p26aās. They are rated for 35a continuous but I canāt find the info for peak discharge. Anyone know what settings I should type in my esc?
For info: esc is dual flipsky6.6 and motors are 190kv 6354 with a 15/44t on 125gummies
The P26a only have a discharge of around 25 a rather then 35 a
Not according to the new data sheet I just saw from molicel