See link for bms 150A Bms The fuse will operate proportional to the fault current, generally it will be a hell of a lot quicker than 0.5 seconds lol. Motor should be fine with over voltage/Current for 5 - 10 seconds. However you are correct it will be slower blow times for over current protection rather then fault conditions. Most of the time the vescs dont run that high of a current mine normally sit at 40 - 45 amps max and dont often go above that on my mountain board see VESC LOG this is just logging a single vesc. Have a read through this page Eskate vesc 6 it has good info on the vesc 6 and pushing its current limits it could be a viable option for us
Hi VeFoil, I have done my first test today, and the ESC was running cold at all time (it’s been water cooled) and giving me plenty of power to fly on a Kitesurf wing. This is not very scientific has I have no way to mesure (Yet)
Ok, the 150A BMS looks nice and with a electronic fuse it should be quite as fast as the ESC.
I was thinking of a mechanical fuse, which you use at ebike batteries.
yeah, I read about a guy using the VESC for a rowing machine and drawing 150A while watercooled.
Since the FETs are able to do 240A with sufficient cooling and only the shunts limit the max amps to 165A it should work out if you have a good watercooling.
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UPDATE, second test and the ESC (Aquastar 240A) fried!!! So this ESC is not up to the requirements.
The water cooling was running and the ESC was not hot, but it looks like one capacitor gave up and luckily there was no fire.
Sorry to hear that Clarin. What pain in the butt and waste of money and I’m sure you were not using anything near 240A… Which ESC are you thinking about now?
@Giga I used a VESC orginally and it didnt like it… though it was not water cooled. But definately hard on the ESC.
what was the problem with the VESC?
Well you have to cool it to drive high amps, otherwise it is limited to like 20-30A.
But if you keep it below 60C you can draw up to 150A
thats not from the Fets the VESC uses, but it is a typical curve for fets.
And if you ever touched a heatsink of a running ESC you know that they get up to 100C quite fast.
It just over heated and would shut down, nothing wrong with it, its just not the right ESC for the job if not water cooled.
I ordered an Alienpower 400A 16s, hope this will be enough!
They are selling also a 300A power switch, which I will connect to my kill switch.
The vesc design is ‘suboptimal’ for cooling(4.12 hardware). All fets are mounted with their cooling pads facing each other. This prevents any good cooling. I had some success using copper cooling fins soldered to the remaining pads on the top. A real solution for waterccoling has to contact the cooling pads and isolate the fets electrically. I like the vesc for testing, but without proper cooling it did not work out for me.
Has anybody used one of the expensive VESC 6?
I love the adjust ability of the VESCs. Especially when running batteries without BMS. The VESC allows to limit battery amps and motor amps separately. And you can configure a soft and hard low voltage cut-off in order to protect your batteries.
I’m thinking about putting a VESC 6 into an aluminium case and filling the case with mineral oil. In fact, I’ve ordered the case already.
Any thoughts?
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Please report on your results. I don’t know much about the vesc 6. I didn’t find the schematic yet. I have modified my current vesc quite much. I like the ability to adjust the software. I have temperature sensors in my burshless motor also connected to the vesc, so I can limit the current before it overheats. Without schematic I can’t do that. The vesc 6 would be much easier to assemble as there seems to be a heatsink by default.
you are right, the 4.12 and X are not good. ERPM limit is lower, FOC problems and unprotected DRV.
The 6 has another design, the problems of the 4.12 were improved and all fets on one side, aluminium case for heat transfer and the parts are around 70€. You can order one in the esk8 forum from users for around 145€ (trampa-boards charge 300GBP).
Big bonus: the design of VESC6 is modular. I already made a request for 20s 160A, which should be much better for the SSS motors.
Also my plan is to make a watercooling for the ESC. You always have some losses at the fets and the more power you draw, the more heat you have and I don’t think aircooling will work in a waterproof case.
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I used a VESC-X and blowed it after some hours. One DirectFet is fried. I used it in BLDC mode, phase current limit 80A, small cooler for each fet and forced air. Current went down within a minute to 70A and less.
I plan to use 4.12 in combination with 4 heatpipes. One is soldered to the Drain of the 3 High Side Fets, three to to the drain of the Low Side Fets. Heatpipes need some cooling sheets and forced air.
Not sure yet which one i should order, Maytech, Flier or Smartech. http://alienpowersystem.com/shop/esc/ev-esc/vesc/
Any suggestions?
Similar tuning could be done with the VESC-X. But first i need to repair it. I am not sure where i could buy the DirectFets.
Nice!
I got the Flier 400A Waterproof Boat ESC which arrives in a couple weeks
Found this one;
http://www.kontronik.com/en/products/speedcontroller/speedcontroller1/kosmik/kosmik-160-hv.html
Quality ESC for helicopters, pretty $$$ tho. I guess this could work without watercooling, just with a heatsink .
Alienpower = Flier ESC
If you want an offer for Flier send mail to this guy
Rafael, Rafa mamba.
rafamambarc@yahoo.com.br
He works with Flier,TP power, cooled outrunners, Leopard etc. and he has a lot experience rc.
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How is your 400A esc working?
Did you get waterproof version in aluminum box or heat shrinked version?
How many amps are you running and is it staying cool with water?
Used twice only, so not much feedback. It’s the shrinking wrap version.
Both time the runs where in the 15 min and it stayed cool the water pump turned on (40 deg) only a few seconds. Still no clue about the amps? For the water cooling, I have mod the front 3D cone with a hole in the center that connects to the front section of my foil, so the water can fill it up (no need of tube inside) and there is a pickup on the top. Works great in fresh water anyway!
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Nice!
Can you send a photo of your cone and pickup?
Here in fusion 360, it’s based on Hiorth v1 and it fits an Alpine mast. The hole on the mast side is not perpendicular to the mast to help the water flow move up. I will try (sadly only in a few months) to see if I need a pump or the pressure is high enough without one. You could also put a small filter before the esc.
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