If a motor is at +40A and you change to “adding” -8A then it should slow down. (Based on my crappy understanding of what’s above)
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The question and posed statement is correct. If you are not regeneratively breaking, the kinetic energy reduction is converted to heat.
This is also called “Plugging”.
This was likely quoted in a way to imply a point, not to take the statements you (@ziploc) made out of context. However, the statement is incorrect in this way - because it contradicts one of the options at the end of the sentence.
You’ve contradicted yourself here. The approach “Plugging” specifically inverts the phase execution and causes the flux to reverse. Thereby producing negative or reverse torque when current is applied. This causes the motor to want to spin against the direction that its already going, which in turn causes the motor kinetically to act against the magnetic field (flux). When this occurs the rotor bars and stator will heat up, and eventually the motor will stop.
Now that all being said, this is all well and good information but alas makes very little difference in the grand scheme of things because @shaman this whole time is referring to a bench test scenario with a simulated load (variable) by using the plugging (reverse phase/flux) method of Induction Motor braking.
Furthermore here is some lite reading for you all regarding the braking methods for Induction Motors.
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I don’t think I contradicted myself. I think you mean to say “you’re wrong”. And perhaps I am in a way…
Yes - agreed completely, but…
Now you will output twice as much heat. You now have to dissipate the heat you would already dissipate through braking PLUS the heat associated with the energy you used to do the braking. So I’m inclined to say we’re really only differing semantically. I said “I don’t think you can slow a motor down by adding energy.” We could debate whether or not you’re adding energy to the motor, when the net is actually removing more energy in the form of heat. But I’d rather not have that debate because there’s hardly ever any point to debating semantics, particularly when I’m pretty sure we’re saying the same thing.
I will say however, that I think Shaman was wrong when he said:
“Will there be some heat dissipated? Yes but only what you would expect from the motor based on the amount of current flowing through it at the time.”
But I offer this with the utmost trepidation as I’m certain he’s 100 times the EE I’ll ever be.
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I think our disconnect and therefore the semantics boil down to the use of Energy in relation to Kinetic, and Inductive maybe we are saying the same thing because of that. Additionally because of that my statement of contradiction is based on my perceived understanding of what ‘energy’ is in this case.
I don’t like taking threads off topic even if its somewhat similar, so I leave my responses rather verbose. Ill concede to the fact that we’re possibly saying the same thing. Especially since the reference material linked in my post specifically explains it.
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Shoot, should have deleted that “either” for clarity. Well played sir.
I’m overdue for an update to everyone.
Beta unit materials have been arriving. The control boards and BOM components are in. Still waiting on the power stage boards. I’ll be finishing out the control boards as I wait for the power stage boards. I had the control boards mostly assembled except a few particular passives, the through-hole components, and the TI specific ICs that I get as free samples.
I don’t think explicitly said it but I did make the transition to USB C.
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cant wait to test them
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Yeah I know… Maybe santa will bring me one if I’m good.
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Looking forward to see the result. I have a 14s scooter coming that needs 2 controllers 
they can fit rather thick units so I will keep eyes on this thread
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Link please of the one you have 
. We need them in the lab (biology).
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thanks a lot 
Just to set the record straight (and hopefully I don’t re-ignite the tangent I started), when I said this to Pedrodemio, I got this part wrong. 
As has been pointed out, you can slow the motor with the addition of energy, and not by charging the battery.
But I’m pretty sure I was correct when I said “So unless I’m wrong (which is definitely possible), you can only brake by either charging the battery or by dissipating the energy as heat.”
When you do slow the motor by adding energy, you now have to dissipate the normal energy of braking plus the energy used to do the braking. This was the part I was stuck on.
So hopefully:
- We’re all in agreement now
- I haven’t re-ignited the tangent
- The universe will forgive me for getting half of it completely wrong (I just couldn’t leave it out there).
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I tried and tried, can’t hold my neck that steady. Bought a used Mantis. It’s an amazing and crazy device. @rey8801 you might want to talk a look, if you’re spending other people’s money 
Sure will have a look. For me is to show and record a surgery I do for research. Otherwise really difficult to teach it to the new people joining the lab.
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Ah don’t bother with Mantis, which are more for operator comfort. Huge field of view, and allow head movement.
Louis Rossmanm on youtube made some very specific recommendations for stereo+camera setups. The camera situation seems to be very rapidly evolving though…
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