I started my build like 6 months ago, but, had to set it aside for over 4 months. Got the table built, just hooking up the electronics
I went for the 24v power supply (will need some advice on stepper reference settings, but, later - i have BIGGER problem now).
So, I had the Mega powered up via the USB to my PC, was just about to download the program to the board, had the 24volt supply on (I had set the ref voltage, but, now i am wondering if i set it for a 12v supply, if it will be diff for 24v?)
Anyway, I was going to unplug it so i could move it, so I unplugged the USB cable - while the 24 volt supply was still on - on the Ramp board.
As soon as I unplugged the USB the Mega board began SMOKING… Totally fried by the time I got the 24v supply unplugged from the AC.
SO… is that “normal” ? I mean, will the Mega board totally fry if we have high voltage power on the Ramp board and turn off power to the Mega? That seems really bad.
I mean, i could see accidentally doing that unplug the use from the PC and not shutting off power to the stepper driver first - Or did i have a bad board? Which board would that be, the Mega or the Ramp? I don’t know if the Ramp board and the 8825 drivers are fried or not, i hope not, the smoke was on the Mega board, i think the power supply chip fried.
So, is this just the way it is, or do i look for something wrong in my set up ??? (I have another Mega board - but - i need to know what is what before i plug it in.
Is it the 24 volt supply?? Should i have used a 12v supply instead? (Hope not, i got 2 of the 24 supplies - the trimmer only takes it down to 19) it seems like the 24 volts fed over into the mega supply somehow?