There are only a few of these in the wild, I know @shambler00117 is using several in onewheels. I also use it in a onewhel for over a year, 1500km without a problem so far. I‘d say if you assemble them well, they a pretty robust. I soldered 12 FETs (CRST030N10N). Battery is 18S, 75.6V
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Has anyone tried 23s on them?
I’d like just the boards with whatever components it comes populated with.
Not working without changing some parts. They are working good at 20s , you can push them maybe to 21s . I am evaluating some options how i could go for 32s but thats more in or less in the planning phase …
I’ve received the boards, they look stunning. Has anyone else had the PCBs produced in black yet? Currently waiting for the remaining components and already starting a draft on the shell design
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I have received all the components necessary for the build. I saw 6.05 was the latest FW on the repo, so I compiled the latest 7.0 for it. Haven’t flashed the fw yet but no errors during compilation. Here are the binaries I compiled: https://github.com/MingoMGx/FOC_KING_VESC_FW_BIN
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Can someone update the assembly guide on the repo? I put the mcu as demonstrated in the assembly guide. Finished the build, powered it on and only power module gave light. Looked around in the thread and saw people have it oriented differently. I shorted the bridge to see if it still powers through usb, but leds are faint and flickering weirdly
Installed a new module onto it with the right orientation and it works!
I have a question on how to make a latching switch work. I am forced to use a key switch. I soldered it to the “short = always on” pads. So when the keyswitch is on its shorted. Turns on beautifully, but when I turn it off it stays on for 5+ minutes before powering down. Anyone know how I could make it work?
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Is there any FOC_KING that failed during operation? What was the failure?
I have builded 4 FOC_KINGs. The last failed probably with leftover wire strain, i rode trought a big pothole and after 10m its started braking the rear motor. On the other one i forgot to connect GND to my display with RX-TX and 5V connected and killed the MCU. One is still working in my escooter, and there is another on in my friends kids car with 16s batt, 200phase, 60line in.
I am used 200 phase and 45A line in on front motor and 65A line in on rear motor with 21S battery.
And i am also started to modify the PCB a bit to my needs. Changed the usb connector to vertical, 0.2mR shunts to push out the reading to 260A, wire out the ntc to mosfets and placed 4x470uF caps to the board and removed the IMU. modified focking
I am able to borrow oscilloscope from my workplace, but i never used one in my life 
But i am curious about the voltage spikes.
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I can only use a keyswitch, will it still function as I expect it to using pin 1 and 2?
just turn the key to on position, and inmediately back to off.
That’s not a proper solution. I looked into the schematics, R9 is the feedback resistor that creates the latch and keeps the circuit on after you release the button. Remove it and the circuit no longer holds itself on, it just directly follows whatever the switch input is doing. So a latching key switch works perfectly. I just tested it and it works exactly as expected.
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Finished building 1 today and took it for a drive. Just had basic motor setup + motor and battery max adjusted and it works wonderfully. Will make the 2nd one for my dual motor escooter soon and then I’ll tune them and see what they can deliver. Also 1 issue I am facing is noise on adc2. The throttle mapper GUI shows it being stable. But when adc2 is setup as regen or as kill switch it randomly activates itself. Even after manually adjusting the mapping. It’s just a brake lever switch with 2 pins. Works fine on my dual ubox and makerbase. I will investigate it further.
Use 10k pulldown and 1uf pulldown on adc chanels. Mines also catching some noise, but this solved the issue.
Edit: reply to your tiktok post. The controller is not capable for 300A. The opamp gain, and the shunt is limiting to 220A
there are also this 2 expansion boards where you dont need this 10k pulldown and 1uf
i made those boards, one for uart and adc and one for vesc express. But there is error on the pcb. If someone needs i have new for the uart and adc.
Is it possible to get your update folded into the official release?
Hi all, I’ve ordered and assembled a couple of boards now and I’m fairly sure I’m suffering from shoot-through. The source or drain are burning up and taking the PCB with them. I’m driving a pretty big motor (Grin All-axle hub motor, VESC says around 140uH inductance) so perhaps the voltage is spiking when the MOSFET turns off. I haven’t been able to get scope traces as it just blows up when I try to start the motor.
How should I go about confirming/fixing this?
I can’t attach images, I think because of account age, but the PCBs are burning up on the reverse side by drain/source and cracking the MOSFETs too.
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