20s Little FOCers on stooge SRB v5#1

48kw?? wow. how the heck do you demand that much power on a skateboard without shorting somethign to heat??

Fat guage wire and a bit too much blind trust that nothings gonna go wrong :rofl:

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I’m guessing high speeds and iron losses.

Oh interesting I knew outrunners had this problem but I guess kind of assumed inrunners didn’t have this problem due to different construction? Or something along those lines.

Yeah I’m pretty nervous about running 20s as it’s
ā€œProblematicā€ though I haven’t had any issues with the little foccerz I definitely trust them.

I will acknowledge that they are probably not the best Vesc possible to run considering my current motors are pretty close to maxing them out.
(But they are what I have as of right now)
Plus I don’t wanna blatantly copy your style / build

I very much appreciate your expertise & take on running it at higher voltage, I’m considering lower voltage but that’s kinda of weird thing to do in my mind ahaha since I’m already running it.

Maybe ill return the motors
Or figure something else out
or not listen and do it :joy:
The cool thing is I impulse bought a second pair of little foccers so I technically could just ef around & find out without damaging my current setup.

Though At certain points this board feels like it’s become more of an engineering project than a board I race actively.

Up in the air what I want to do and will do.
But the fomo as being left in the dust on the track is real.

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It Realistically it Does NOT need 20s at all
And the gain is borderline nothing…

I’d likely never touch the speeds it would be capable of.

Vs the risks seem pretty gnarly… not really sure what I’m thinking half the time but the desire to experiment / learn from mistakes is there.

The only way do properly achieve this is massive gear reduction like it was mentioned above.

It especially makes Sense to take advantage of the extra voltage / RPM it has to offer as the phase amps are kind of lacking and overall power output is far less than say your tronics.

But I’m not sure overall power output wattage really makes your board ā€œfasterā€ after a certain point how much power are you effectively using? How much power is lost via heat/ironlosses ?

… part of me wants to believe you can be just as fast with less powerful overall escs? ( In reference to wattage output)

I am willing to design a way over engineered mount / reduction system + adapter blocks for different mounting patterns Specially design for inrunners with a certain kv window

But that’s also uncharted territory for me in my personal design experience, it will probably take me another racing season for me to develop and test.

Which might be worth it? Considering inrunners are an undenying truth for esk8 racing.

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48KW is insane! My friend has done 30KW with one tronic on his scooter. These tronics are no joke

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That’s awesome thank you for the information and pcb pic

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Wow these are big (crispy dollar bill for scale because that’s all I have left)

The weight of each motor makes me hesitant to keep them maneuverability seems like it will definitely more of a battle.

unsure at this very moment I Will keep them.

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I finally had time to dig through Audio Eltn Class Slideshow from my nearly but now Deleted school account :frowning: with That Special trick I was Talking about back in Jan @Ash

So Traditionally for Guitars / Basses n such they Use a two prong Cable that Is susceptible to ā€œNoise & Interferanceā€

But I was Introduced to this three prong cable in my Audio ELTN Class Back in (2022) that from my understanding essentially used the 3rd prong as some sort of Driving Force to eliminate noise & inference before exiting either side of the cable connections.

Ive been wondering if this special type of cable could be used for ever so delicate PPM cables / Can Cables / UART whatever that could be potentially at risk for interferance discrepancies.

I can create a link to the Complete Slideshow for those who want to read more about it

Also curious if what I just shared
is the same thing you were referencing utilizing ā€œTSP Wireā€ awhile Back? @tuckjohn

Sorry if it is I have a great lack of understanding with this kind if stuff :joy:

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There’re entire textbooks and PHD careers on just the topic of EMI and EMI mitigation (btw, Electromagnetic Compatibility Engineering by Henry W. Ott is fantastic).

Basically, different applications need to protect from different things, requiring subtle but different techniques, and often more then one at a time. It quickly becomes a rabbit hole that’s very easy to come out with misconceptions. I’ve been working with this stuff for years and I’m still learning things, so I’m no expert haha.

Assuming I understand how those audio ā€œ3 prongā€ cables work, they’re doing something quite similar to using TSP cabling for CAN communication. But they’re quite different, solving different issues.

Audio signals are low level, analog, ground-referenced signals. CAN communication is digital differential (ground analogous) signals. They need to be treated differently when considering EMI protections

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everyone gets balanced wrong.

it’s a differentially encoded signal on a ā€œbalancedā€, meaning equal impedence, pair of wires. such that any noise induced is induced in both, and dosen’t change the difference between them ie the signal.

so it’s both matched impedence (balanced) and the differential encoding/decoding that help to reduce the noise.

your second picture, is just talking about how to take an unbalanced instrument and hook it up to something expecting a balanced input and have it get an audio signal in.

to my understanding, can bus is differentially encoded, and those termination resistors are balancing the impedance between them. servocontrol is not. uart… doesn’t dictate the physical protocol, I think, so it can be used with something doing differential encoding on balnaced wires but… i don’t think ours does.

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image

a close up of a cartoon character with one eye

is twisting the wire power leads the only way to help match Impedance In this Case?