do you have on email address to communicate on my project?
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PM sent
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Is there a video link to his stuff?
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Hello @shaman and everybody. I am interested into building one of these FOCers for an electric longboard. My plan is to use 10s or 12s battery pack with each series with up to 15 pcs in parralel. Reason why I will use this much batterys in parralel is because they are upcycled and they will have capacity between 1500 to 2000 mAh. And with some what unknow C ratings. Goal for my longboard is max speed of 55 60-ish km/h.
So my question is which motor should I use where can I buy it. Which wheels should I use and gear ratios. I used esk8 calc but I always get unrealistic results. And if some how is possible link stuff that is realtivly cheap and of good quality.
And for @shaman is it possible to use any other MOSFETs with higher max voltage across drain-source. I personaly think with higher voltage and simular characteristics of MOSFETs you put in BOM will reduce power dispitation on them and probably wonky donkynes at higher currents then 50 A.
Thanks in advance and sorry for my english.
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100+ 18650 cell batteries have to be on a esk8 with a considerable amount of power. Probably want 3000W+ dual if you think your batteries could supply that. You seem the budget type so I’d check out dickyho motors on eBay or torqueboards for high end ones.
You won’t see a lot of low capacity low discharge used cells being made into diy esk8 batteries because it’s worth it to buy $200-400 in quality cells and not have to worry about it.
I’d highly recommend you post in the Battery builder thread with pictures of what you might attempt for some positive criticism.
https://forum.esk8.news/t/noob-question-thread-ask-your-questions-here
This thread was made for you, Ask away!
Thanks for advice but I am not going to use random batterys that are used. I will try to use ones that are from same company and if possible will find datasheets for them so I can clasify them by category of writen capacity, mesures capacity and C ratings from datasheets so that pack will not fry. And of course I will buy a good quality BMS for them.
And for motors I dont need kick ass high tourqe high accteleration ones . I am trying to make a longboard that is capable of long rides and top speed (if needed for the thril) of 55 km/h.
I think the best advice I can give is really REALLY read up before you make decisions on parts. Take a look at what other people are doing and draw inspiration and knowledge from that.
Last point is that unless it’s about the Cheap FOCer you should talk about your build plans in another thread. I’d recommend you read for a week or two then make your own thread. You will find a few years of more information on the old builders forums so don’t forgot to check the old posts there out.
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Have read the whole thread. I was thinking to build an electric longboard for little bit more than 2 years. Read about ESCs, BLDC motors, battery packs and their managment. I posted here because plan is to make Cheap FOCer, and also to read and see what others have build and learn more from their experience. If I will not find an answer here ofcourse I will ask in another thread.
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Damn Christophe now I get why you keep breaking and I keep repairing your stuff haha!
You crazy ass wanna jump at 100km/h you’re gonna need some kind of exoskeleton
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You can but I don’t think you have much to gain by doing so. Power dissipation in the MOSFETs is a function of Rds(on), switching frequency, and rise/fall times. A higher voltage rating often comes with a higher Rds(on). Also the DRV is the limiting factor for system voltage at an abs max of 60V
The instability seen at 40A+ is most likely a layout issue. Those high currents can easily couple noise into sensitive sense signals if layout isn’t good. It can also cause bad inductive kickback leading to voltage spikes. I do my best in the Cheap FOCer 2 to address this issue. Stay tuned for when I start a thread on that…
As for the not-FOCer stuff, you’ll have to ask about that on the other relevant threads as mentioned by @Fosterqc
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Makes sense thanks.
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Hey I just found in my country the store with more options for chips and found DRV8302DCAR what is difference between DRV8302DCA and DRV8302DCAR and is it possible to use second one. Is it possible to use STM32F205RGT6 instead STM32F405RGT6 for MCU.
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This will just be a difference in how their packed. Tape and real, tube, or tray.
Probably not
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Thank you
Hello me again. Is this good replacmemt for lcsc to-220 mosfet.
FQP65N06-FSC
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