Hello All, I just got my OB Mini Mill built, I bought the cnc xpro v3 board with it. The board powers on and connects to GBRL Panel and the activity lights flash on the usb indicator, but the stepper drivers do not appear to have any power. I have connected both a 500w atx power supply, and an 800w hp 12.5v server power supply at separate times and neither seems to power the motors. When I plug the Atx power supply in, and then the usb to the computer the fans on the power supply turn on. When I unplug the atx and plugin the hp server power supply I can read 12.5v on the 2 input terminals, but again the motor drivers show no indication of power. And the motors do not move or make any noise when attempting to job in GRBL panel. Any ideas? Thanks, Nuker- I have also tested 3 stepper motors after checking the wiring 20 times, the coils are in the correct places for A and B coils, and I have confirmed with an ohm meter and continuity meter.
Maybe you need to adjust the pots on the stepper drivers? (I don't have the Xpro, but my Gradus M1 Pro had the same symptoms when I first hooked up and I had to set the VRef pots.)
Ahh man, I can't explain what was happening, But it is fixed now. I at first was using an ATX power supply into the atx plug in, it was coming on, I confirmed voltage but the xpro did not power the stepper drivers. Step 2 I grabbed an HP DPS-800 power supply and confirmed 12.28v out, Plugged it into the 2 terminals on the xpro, confrimed voltage on the pins. Nothing the board would not power up except the USB powered side. Step 3, I grab another atx power supply jump it to turn on, strip 2 12v rail wires, Confirm 12v output voltage screw it into the input terminals on the xcarve and magic everything is powering up and I can move the steppers via software. I have absolutely no idea why the HP power supply putting out 12.28v won't power the board. Nuker-
You said you confirmed the voltage, was that with everything plugged in? many ATX PSU's need a substantial load on the 5V rail to fully power up or the output might look like 12v but soon after it is powered it will go into power save mode with no load (or not enough load) on the 5V rail.. most times to get a ATX PSU to power you have to put a 1ohm 10watt sandbar resistor on a black to red (5V) wire, not sure how the X-pro gets around this, it might not pull enough for some PSU's. Honestly I would recommend buying a 24V PSU for it as this will get you more speed out of the motors.
A little late to this party. My first thought was the same as Gary's. ATX PSUs usually need a load. I think it's false economy using a PC power supply. More trouble than not and really under utilizing the HW at 12V.
