Esab Ultrarex UXD-P2000 Upgrade Project

So did the tuning and was able to to use the THC correctly.
Still working on the tuning though.
Would it be wise to start using the last version of linuxcnc with qtplasmac?

Well no luck with this setup
My friend was trying to cut a piece. The torch didn’t fire up for some reason. The machine started moving without the machine torch on. He stopped the job then tried to jog the machine to the starting point but there as an error and he kept pressing the keyboard without taking notice of the error. Linuxcnc froze then and we tried to kill it but no luck. We rebooted the machine. Now whenever we click on the enable button the esab machine jolts and generates an error. The machine is now unusable. If you enable the estop the machine can be enabled but when you try to jog you get the estop error. We have disconnected the esab motors from the mesa but no luck. The z is still working fine.

LinuxCNC froze! That’s the first time I’ve ever heard of that happening. In your case, since it’s a plasma machine, the risk of harm is relatively low when the control system locks up. But if this had occurred on a large machine, it could’ve been disastrous. That’s exactly why I always advocate for an external hardwired E-stops which are fail-safe and operate independently of the software layers. Relying on on-screen gui emergency stops or and wireless pendant estop are inherently unsafe, as they can create a false sense of security. As you experience shows, you could not stop the machine and you had to reboot the computer.

The machine did stop the cutting job. We stopped the job because the torch didn’t fire. No idea why. Last time it worked without issues. LinuxCNC froze when my friend tried jogging the machine back to the starting point of the cut. No idea why it did that. Maybe pressing the keyboard continuously caused the freeze !
We do have a physical emergency stop wired to the setup so no worries there.
Now the issue is the machine just jolts when enabled and we get a joint 0 error. I even upgraded to the last version of linuxcnc but I get the same behaviour. Machine Enable > jolt with error !

If you did not change anything in the hal/ini files, this points to a hardware failure of some kind.

Do the encoders still read the axis position if you move them by hand?

 

I put an old working backup of the ini and hal files just in case. Same outcome. The x and y encoders do read fine when moved by hand.

I guess the next step would be to make sure that the analog output path is OK.

A quick check would be to make sure that the analog output voltage of the 7I77
is near 0V when LinuxCNC is not running.

So both motors are triggered and do move (jolt) when I enable the machine in linuxcnc. Looks like a central command goes to both motors to move. Powering the esab machine without linuxcnc is fine. No movement. Will check the voltage and report back.

How about reflashing the mesa 7i77 firmware?

I started linuxcnc in debug mode and when I enable the machine I get this error:

joint 0 following error
emc/task/taskintf.cc 976: Error on joint 0, command number 226
task: main loop took 0.112439 seconds

 

Not a firmware issue.

I would not expect motion until you enable the drives.

If there is an analog output issue, it typically shows up as a non-zero
output voltage when the 7I77 is powered.