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UC400ETH moves two axes

PostPosted: Wed Jan 03, 2018 5:38 pm
by Toecutter
I have a problem with my UC400ETH, if I move the Y-axis at the same time always moves the X-axis very slowly, I swap the pins in Mach3 between these two axes, it is the same only the Y-axis only moving in one direction.
Mach3 I have already reinstalled, I have now just once measured voltage on the pins of the UC400ETH. If the UC400 is just powered, I have 5V on the Step / Dir pins for the X-axis, 5V on the Y-axis stepp pin, and no Z-axis pin, is that ok? The Z axis is the only axis that works normally.
The machine has run so far with a Smootstepper USB, without any problems.

Thank you
Greetings Rene

Re: UC400ETH moves two axes

PostPosted: Wed Jan 03, 2018 6:09 pm
by cncdrive

It sounds like a ground loop somewhere in your system. Something is picking up noise.
Maybe the power supply of the UC400ETH is effected by the stepper drives creating the EMI and a wrong grounding causing the ground potential to jump producing steps for the drive.
Or the step/dir wires of the drive is picking up the noise. Or the drive internally picking up the noise.

I can't tell you what voltage levels should be on the output pins, because it depends on your configuration and the actual states set by Mach3,
for example the dir pin is 0V when the axis moved to one direction and 5V when moved to the other.
But any outputs can have 0V or 5V voltage levels.

The best to do is to measure the outputs with an oscilloscope without drives connected to the system to see if there are any step pulses for the axis which moves when it does not have to.
And if there are no step signals that way then connect the stepper drives and measure again. And depending on the results you could go on with debugging the system.