With the spintend 75100 and the makerx 75100, they’re both using the Vesc 75300 firmware and I assume can be programmed to 300 motor and battery amps. The “peak” rating here states 200amps. Is that motor and battery amps and is it for a period of time? Can I program it up to 300 and be ok if I’m only at near that high current for seconds at most? At worst will it have a high temp shutdown or could it be worse?
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Why do some of the new 75/300 designs have cables for 3 motors, is it really for three motors (go karts?)? The Trampa site didn’t really give me information or I’m shite at looking…
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its just one motor. just 3 times the cable for 3 times the ampacity or whatever
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I’d be curious what that wiring diagram even looks like
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just connect them all to one phase
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They should be using a “75100” firmware that either Spintend or MakerX would upload to the VESC project github.
That’s why they should use their own firmware. Running the 75_300 firmware on these units is basically like running the no limit firmware. I doubt it can handle 300A. The actual 75_300 hardware typically has 18 mosfets, these 75100 only have 6, and each mosfet is nearly identical in specs, so the current rating on the 6 fet version has to be quite a bit lower.
At worst you will blow a mosfet like a fuse… and a lot of times that takes out half the board with it making it pretty much unrepairable.
I’d probably stick to what their website says for amps.
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I don’t trust current numbers coming from folks who would profit from a sale.
Just my $0.02
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It’s also causing an issue with current measurements precession. Those designs, using 6 Fets and one shunt per phase have a terrible ability to gather precise feedback data when used in connection with a FW that is designed for 18 Fets and 3 shunts in parallel.
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We could also use one thick cable per phase. This would be hard to solder neatly to the PCB and it would be very stiff. 3 thinner cables are a lot more space saving and keep things more compact.
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They use their own firmware though right? Can u post evidence of how they don’t measure current well?
Added some really interesting VESC controllers coming out of 3 Shul Motors in India. They seem designed for electric motorcycles and the big ones support some crazy amps. They have a “micro” 20s 300A version that looks skateboard sized.
Some videos with glowing brakes and wheelies on their prototype page
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Looking on this site and others I see attempts to cool the fets. Maybe this isn’t the right place to ask but what about adding copper heat sinks to each fet? They need to be electrically isolated?
IMO the best cooling designs are where the mosfets are cooled from the bottom of the PCB they are attached to, not the top of the epoxy package. The Unity and Stormcore (and the new Aluminum PCB 75100) got this right. 3 Shul also seems to be designing it with cooling from the bottom of the PCB. It’s one of the reasons the 4.12 was such a poor thermal performer even with a heatsink added. The sandwiched mosfets just fed heat into eachother with nowhere for it to dissipate since it transfers heat much faster into the copper PCB traces than through the epoxy package.
The DirectFET metal package used in the VESC 6 seems to try to improve cooling by allowing a more efficient transfer of heat through it’s metal case to a heatsink, but in my testing that ESC is only middle of the road in terms of thermal performance.
From what I’ve seen in tests, copper vs aluminum heat sinks don’t make a noticeable difference in performance.
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I ordered the aluminum 75100 I told u. Fregin steal on sale. With it running firmware that allows I think 300 amps I’d like to get up there as high as possible. Is the only risk an over-temp shut-down? My battery will do 130amps but like to set motor amps to at least 140. What’s ur forecast and any advice on cooling it? I guess just leave it in the wind and not add small sinks to anything inside?
And will do 72v full charge and run strong regen brake with 83100 mid drive motor.
I’m not into eskate anymore!
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Are there any VESC4 based ESCs that have phase shunts? I’m tring to run silent HFI for some context.
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No, phase shunts were the major design change with the V6 schematic. All the V4s are based on the original schematic which use low side shunts.
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Dammit, alright thanks.
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Hello, we are testing this ESC hobbyking turnigy-sk8-v2-80a-3-12s-single-motor-skateboard-esc
With maytech sensored-motors mto5065-170-ha-c?variant=29503884492894
We configure the 14pole and 6S. We power it from 24V power supply 8A.
The VESC tool recognizes the sensored motor and we can rotate it. The problem is that we can stop it with hand and the highest current we get is around 4-5A. In the program we set 10A in motor config and at the bottom of the VESC tool 20A, but the current does not look to increase on the power supply. Another thing is that if we control it from the bottom panel we enter 5000RPM it rotates at 700RPM. Has somebody faced such a problem? What can be the problem here?
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Just drop it there, if are subjects to consider
MakerX G300
Hobbywing Max 4
Of course, if someone tried one of those, share feedbacks
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