I accidentally unplugged a z stepper why it was homed
One side came spinning down
( ive noticed when the steppers spin and the power is unplugged the led screen will light up a bit )
When its plugged in via usb its recognized by the computer and repetier host still connected to it… I also have a orange light flashing on the board when its plugged via usb
Am i screwed?
You will hear sometimes we talk about “back EMF” – any electrical motor is also a generator. When the motor receives mechanical power, it will try to convert some of that into electrical power. It’s much less efficient that way than it is turning electrical power into mechanical power, but it does it nonetheless.
That voltage generated is (often) enough to light LEDs or generate voltage on the low voltage side of the board (5V/3V3) so the LCD will power up briefly. If you could keep it moving fast enough for long enough, it might even be able to boot the processor. It won’t harm the board though, since that oltage still goes through the regulator. If you could get it going fast enough, you might even be able to get a fan going. Probably not though.
The drivers don’t like the motors being unplugged while they’re powered, and it can damage the driver chip. You should probably unplug the power from the board, plug the motor in and then give it a try. In most cases, the board and chip will be fine.
Hey thank you for the reply!
I tryed to plug everything back up again and its dead…
Unless i plug in the usb but i still only get 1 small orange light on the board. No green led… No power to lcd.
I suggest you check your fuses as a first step to diagnose the problem. If you blew a driver chip as suggested by Dan, you could rewire your machine in the serial configuration, which only uses three drivers.
Robert beat me to it. Check your fuses. There are 3 fuses on the board, labelled F2, F3 and F4. F4 is an ATO style fuse, and is unimportant, as it’s for the heated bed function that we don’t use for CNC.
F2 is between the power connectors and a regulator capacitor can on the edge of the board. F3 is just inboard of the power connectors. One of them covers the main logic power and the other is for motor power.
It’s also worth checking that your power supply is still providing 12V, and that you didn’t do anything to that.