It’s a single vesc 
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Only means having 2 
space is not a problem with top mount emtb
They so mini, space is not an issue at all with them. If they work for mtb need to be elaborated first. Definitely not for heavy off-roading
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If they get here in time I’ll try them on the MTB
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…unless you use 4 because now so much space inside
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That would be an alternative, but 4 motors, 4 mounts 4 transmission, that makes things heavy and more expensive
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I have two untested atm. On vacation so alot of other shit happening.
For anyone who buys this do not power them up without a sparkswitch or electrolytic cap over the powerleads(preferably both). Its like begging for it to blow up on first use. It only has ceramics inside which produces a naughty inrushcurrent so def try solder atleast one larger electrolytic on the wires first. The higher ESR on them help alot for this specific scenario.
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Get something like 4x 5065 and belts…that would be a nice 4WD
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I have one with 4x6384 and chains. Think that’s enough 
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Had a first spin with the mini vescs.
It was just 4km but wanted to share the results non the less.
I run them on MAD hubs 130kV.
At this run at 30A bat max and 50A motor max. Out of a reason I couldn’t find out yet I can’t set up sensors. The hubs without temp sensors but I get an overtemp fault non the less. So for now it’s sensorless.
4km are like nothing but first impression is that they pretty fast get up to 50degree Celsius, but than stay around that as long as you drive in a stop and go city style.
Here the numbers from the metr app.
I will tweak a bit more on the setup and hope that the rain will not continue the next days, so that I can make a longer ride to see how much the temperature rises when driving without stops for some kilometers.
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Interesting, is it 10s or 12s?
Got the same setup but decided on running dual vesc6 for now since i dont trust these yet. (Especially not on 12s). Plan on using em with older hummies and 8s. Mounted on an alu plate exposed to airflow.
Before you manage push em further. Solder a larger electrolytic on the dc-inlet. Personaly I also beefed up the high current traces on the pcb for good meassure.
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Yes it’s 12s.
Can you translate that for electrotechnical noobs please
What and where exactly and why
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There is no problem with running that thing at 50°C (or beyond that) after all thats maybe 30-40°C above ambient which is not that much temperature delta.
The lowest temperature rating of the components inside is probably 85°C (plastic housing of the connectors), 70 or 80°C won’t kill a VESC and the normal temperature limits would limit the power throughput beyond that.
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Its in my earlier post, like 2-3 posts up. An electrolytic cap helps with nasty inrush currents. Will prolong the life of your esc.
63V 500uF+ should suffice
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The STM32F405RG is only rated up to 85°C.
The electrolytic capacitors may also only be rated up to 85°C, but there are others that are rated higher, not sure which one they are using.
The DRV is rated up to 125°C
Power MOSFETs 175°C
@linsus I did the math, at these switching frequencies, even at 100A, 700uF is the minimum needed. Im guessing the caps they already on the board meet this minimum.
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Its not bout the capacitance. The ceramic caps have so low esr they will blow the powerstage up when u plug shit in. electrolytics ESR helps complement this issue.
Also, ceramics actual capacitance ( especially at high end voltage span) is about 60% of rated. You have to add that to your calculations.
The Mini FOC has no electrolytic capacitors, a bunch of ceramics instead.
I might be mistaken but I read the datasheet of the Stm32 as 85°C max. ambient and 105°C max. temp.
Over all it’s still fine speaking of VESC temperature is the MOSFET thermistor anyways.
Wait wtf it doesnt use any eletrolytics???
Ok yeah add an electrolytic, the primary concern is ceramic caps can’t provide as much capacitance and thus don’t store enough energy for the pulses during switching. I’ve never heard of low esr causing powerstages to fail. Damage from inrush currents largely arises from large capacitances, which happens when too large electrolytic capacitors are used.
And yes, always use ceramic caps rated for double the nominal input voltage.
The STM32F405RGT6 is rated for 85°C max.
The STM32F405RGT7, the industrial range rated part is rated for 105°C max.
All vescs use the T6, it’s cheaper and was specified in the original vedder schematics.
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You guys might as well be speaking mandarin. Got no clue what you’re saying to add where and why. Esc speak is still way out if my league. Jusr when I think im starting to understand esk8…
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