Cheap FOCer! (VESC compatible 4.12 redesign)

I’m seriously going to consider this approach. Maybe I can finally get an LLC going and start feeding the DIY community cool stuff. All open source of course!

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I want to make some cases or cnc heatsinks for this for sure :slight_smile:

Theres not enough community projects here

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:star_struck: Then I will patiently waiting for second generation “100Vesc”

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Not to bring you down, but just a caveat. Yes 100V is the max but I wouldn’t push it that high. Always leave room in the design for transients/spikes so you’re not constantly riding the line between working and broken. I am advertising the high voltage design to operate up to 84V(20s).

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Sure, I want it to have a reliable 12-14s max

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Good luck with that :smirk: everyone here wants to push it as far as they can. I prefer to know the thing that holds my life in its hands is not operating at max voltage while feeding square waves into inductors…

I will only run the DRV8302 at 42V but mostly folks here push it to 50.4V and some even 54.6V

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I’m sure I can come up with some fancy disclaimer. Something like… “Do not FOC the Cheap FOCer outside of it’s advertised FOCing limits. You risk damaging yourself, the controller and your ability to FOC any further.”

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it think that wins the best caption of 2019.

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So I was thinking of switching to a vertical mounted mini USB port. These are through-hole components and should be easy to solder by hand. The orientation would also grant easier access to the USB port while the Cheap FOCer is in an enclosure like the hammond 1590b. The only downside is that LCSC is out of stock on those and idk for how long. I was hoping to be able to pitch a BOM to everyone that is 100% from LCSC.

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That would be cool! Would you utilize the hammond enclosures or go with something else?

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I‘m sure he will design something totally new :stuck_out_tongue_winking_eye: @moon a dual heat sink case would be great :+1:

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We can do both. But we can also have a custom heatsink…

Lol how dare you, of all people! :wink:

I believe 60vdc through the fingertips is where it starts to get very dangerous for humans. I’m pretty close to my personal limits with with 13-14s.

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@shaman can I make 1 request? The canbus implementation on 4.xx hardware doesn’t have adequate protection. If 2 vesc are connected, they must be powered on and off at the same time, and cannot be disconnected when they are on.

6.xx hardware, and I think the most recent version of FOCBOX has improved the canbus protections. It would be great if you could cherrypick this improvement. Sorry, I’m not smart enough to have any specific details.

But this issue has fried many vescs. Personally, despite being aware of the issue, I had a xt60 disconnect on a vesc and lost 2 vesc (it’s on my todo list to repair).

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I got the 6.4 schematics in front of me right now. Let me see what going on with CAN stuff.

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So the VESC 6.4 uses an automotive grade CAN transceiver. It can handle a lot more abuse from transients and such. The CAN transceiver from 4.12 is an older TI transceiver that is lower-class industrial grade.

There is a TI drop-in replacement I can use to replace the old transceiver. It’s the TCAN1042-Q1. It’s automotive grade as well and should be able to handle the abuse just fine. Note that this will have to be proven as a fix by conducting the procedures mentioned that would kill older VESCs.

I’ll change the BOM to use the TCAN1042-Q1. I might be able to also add a spot for a TVS diode on the bus lines that would further help protect the system from spikes.

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What’s the danger?!

I’m riding dual vesc 4.12, canbus connected. The xt60 to the battery slipped off on one vesc, and boom, hot canbus chips, no startup. Disconnected canbus, one vesc won’t turn on, hot canbus chip. The other turns on with hot canbus chip, worked with split ppm, but stopped turning on a few days later.

the xt60 that slipped off was under zero tension, very surprised. Now I make sure the bananas are tight, or tape or zip tie them together…

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You may be able to restore single motor function by removing the CAN transceiver from your broken VESCs. It could be that it’s shorted on the inside and drawing too much current from the 3.3V regulator causing the STM to brownout.

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Yah I have canbus chips in. Repair is on the long todo list. :slight_smile: