I have a myxa ESC that I have used many times before successfully, and a fully wired aircraft that still works. (It has 12 servos and 6 ESCs, 5 now, wired on to the 2 can buses on the pixhawk).
After powering on the aircraft, all the actuators seemed to work normally - servos were actuating properly and motors were spinning appropriately. About 30 seconds into my systems check, an ESC started smoking. I immediately disconnected power, but below you can see an image of the fried ESC.
What is that component, and why did it burn? After inspecting the wiring, there are no shorts or unexpected continuities to be found.
