Thank you, Shaman. Yes, I was also thinking of cutting negative as a plan B. I got one of these switches as you suggested as well. So I will just go for that negative cut off.
Really appreciate you help mate.
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By the way, I was also thinking of implementing shutdown according to sensor data, like if ambient temp is reached then motor is switched off. Do you think, arduino can toggle short of those two pins and stop functioning of the motor? This would be like soft stop, but arduino itself would not control duty cycle as potentiometer would be connected to VESC only.
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Yeah a digital device should be able to shut down the CFOC2 through the ON/OFF pins but not directly. I would do it through a small N-channel MOSFET though. The MOSFET should be rated 60V or better. Use the Arduino to control the gate of the MOSFET and have the MOSFET be the one to bridge the Switch pin to ground. Make sure the mosfet can sufficiently be turned on by 5V or whatever the Arduino would be putting out.
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Also If the motor doesn’t have a temp sensor, then you could use the motor temp input for the ambient temp measurement. Then the controller itself can manage based on that input.
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I thought of using relay for this purpose. I have quite a few of them (5V relays). I now use this setup (with relays) on my scooter. So far it seems to be doing good work.
Anyway, really appreciate your quick answers and help.
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Updated my listing with US prices.
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@shaman Hey, I thought I would share my experience after connecting VESC with 36V power supply and mushroom-type emergency button. I connected that button in series on ground, i.e. ground was cut by emergency button. After I turned on everything, tried to spin the motor (I turned it just slowly, all OK), everything worked fine. When I pushed the button, everything turned off as it was supposed to. But when I released the button, my 36V power supply blew… the fuse blew. I checked now, but at least FETs and diode bridge are cooked… Not really sure what happened. I used this power supply https://www.aliexpress.com/item/4000781489664.html
I think that PS might have been damaged after it was switched OFF and when I turned on it just blew due to the damage made… I set regeneration current to 0 on VESC. It is so frustrating… every time I got into something with motors… it usually ends up like that. The only difference here is that I use power supply instead of battery. Do you have any ideas, what is wrong and how to manage that stopping? Now I am afraid of any stopping (even with two swich-off pins on FOC’er) as I am afraid of any kind of damage…
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First off, I’m sorry everything ended in destruction. That’s not a fun situation to deal with…but let’s investigate.
I’ll need as much detail as possible here in order to understand the scenario and I have some questions.
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After the emergency turnoff event(button push), was the power supply still turned on? If so, then the releasing the emergency switch(completing the power circuit) would have caused a massive transient that wreaked the havoc you experienced. The better sequence here would have been to engage the emergency cutoff, then disconnect or turn off the power supply, then release the emergency cutoff.
The initial emergency cutoff could have also caused a massive inductive kickback(voltage spike) that might have damaged something. -
Is it possible to relocate the emergency cutoff to the AC input of the power supply?
Thank you for quick response. Here is additional info.
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Yes, power supply was still on after switch was pressed (that cut off power to FOCer). When I released the button it has not been switched off and then on. Do you think FOCer could have also been damaged? I have not tested that yet as I do not have PSU now. I am planning to get one, but this time for like hundred euros as I do not have time to wait for another month from aliexpress. Moreover, those fets that burned cost like 8.5e each and with diode bridge (and perhaps something more) that might reach easily >20-25e alone.
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It might be possible, but That would require me to move 220V cables to that point, where that emergency switch is. It is quite far away from PSU and that part with motor actually moves, thus having 220V cables that are flexed all the time makes me worry… 36V cables can be flexed… they will not kill anyone…
Moreover, what could have happened if I had used two pins of VESC for this emergency switch off? Would have been the same result here?
Thank you.
It’s possible
The controller would have just powered off and the high-current power loop (supply positive -> controller power stage --> motor phase --> supply ground) would not have been opened.
Do you think that installing button on positive side would have changed something? So do you suggest installing that emergency to FOC’er two pins instead?
Thanks
FOCer seems to be alive, works fine. Other components seem to be fine as well. Just that PSU…
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Hey is there some rough eta on 1.1?
I would like to know if its worth the wait for the price of PNP transistors 
1.0 isn’t released outside of beta/dev branch yet… That said, not sure if I recall seeing @shaman mention anything regarding 1.1 at this point.
Id say its going to be “Eventually™” as he’s been focusing more on the Super/Mother/Little FOCer plans as of late.
I wonder if there’s anyone in the crowd that’s enough of an EE to make the changes Shaman has in mind and get him to bless them?
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Hi, what could be the problem? I get this error message when I try to connect via USB.
Canbus also not working. I got a similar error once on canbus and since then the scan canbus function can’t find anything. I think I would need split PPM but I can’t program the VESC in the vesc tool… maybe BT would work to program it but I don’t have a working and set up BT module. Btw I don’t see any damage on the PCB.
Edit: Sometimes I also get this error.
For like half a minute, out of a sudden both sides were working. Now again only one side works at a time… maybe the cable could be bad?
Also I have an update since then… I drove 2km with a single motor, a capacitor broke off due to vibrations. Thankfully I knew what happened and I bridged the two pins of the capacitor before I touched it… Is there any other way to use capacitors? Like a separate capacitor bank? If I would want a separate capacitorbank, how would I need to connect it?
Fold the capacitors over the board and use some neutral cure silicone as a strain relief.
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I cut the legs too short for that when I initally soldered these on… so thats sadly not an option unless I buy new capacitors. Is a separate capacitorbank not possible / not recommended?
edit: i gotta buy 1 at least because the remainder of the broken leg is about 1mm.
but if I were to buy a few new, I would rather make a separate capacitor bank, with a little more capacitance if thats possible.
There’s nothing wrong with soldering on legs long enough to allow you to bend the caps back over the board. And it could save you replacing the one that broke off.
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