I have a new Atezr L2 24W laser since a few weeks and am testing this software out. I am facing a issue tough that i believe being caused by the software.
It happens from time to time that a project (in the middle of the print bed, with plenty of margin all around, burnt with absolute coords) triggers a “Alarm1: hard limit triggered” message. it happens randomly, on different points of the same project.
I tried restarting the laser, checking all endswitches, but couldnt find anything. Restarting the laser does not solve the problem. the only thing that solves the problem is to completely close and reopen the program. That solves the issue until it reappears hours or days later. if i do not restart the problem, the next burn will not finish and stop in a random location with the above mentioned error.
The machine is homed, the machine is stable and well assembled without wiggle, nor lockups.
That message comes from the GRBL controller in the laser, so it originates due to a hardware condition. LightBurn has nothing to do with it, apart from displaying the controller’s error message.
Typically, a GRBL machine configured with Hard Limits enabled ($21=1) will have a limit switch at both ends of both axes.
Does your machine have four limit switches installed? If it does not, then set $21=0.
The caution in the GRBL doc is worth noting:
We strongly advise taking electric interference prevention measures
Because the 24 W laser module draws a very large current from the power supply, you may be seeing problems due to inadequate wire sizes, loose connections, or an inadequate / flaky power supply. High currents can induce glitches in the long wires from the limit switches, so that the controller sees a switch activation when the switch is obviously not triggered.
Although we’d like to believe a “new Atezr L2 24W laser” would be correctly configured with reliable hardware, that may not be the case. Verify that the switches are working correctly and all the connections (including the laser head) are snug.
Cheap USB cables are susceptical to interferrance from Flouro lights, it may be as simple as replacing USB cable, which I would recommend doing anyway.
Ok thanks, the strange thing is, that when because of a mistake i make i really hit the endswithces, the error is different… cant recall it right now, but has a different wording. womething like “machine exceedes maxium range of motion”.
Thanks! mine has 2 for each axis. so the default value should be correct, right?
I just checked all wires again while writing this post, and noted that one cable made the mashine beep when touched. (did not happen yesterday…) i unplugged it, and connected it again and it sopped now. I hope that this was the problem and that it is fixed now. I will report back! thank you!
Yup, different problem, different message, both from the controller.
All of the problems with limits boil down to the machine not homing correctly, either due to mechanical / electrical problems or configuration issues. Solving the root problem fixes pretty nearly all of them, but it’s difficult to find intermittent problems.
Bingo!
The problem may be a poorly crimped wire or a badly seated pin inside the connector, both of which can be repaired, but shouldn’t happen in a new machine.
I recommend starting a warranty issue with the seller right now to avoid issues with being “too late”; they may send you a new cable based on your description of what happens when you just touch the wiring. If the problem happens again, you’ll be ready.
Not sure I can follow you on this… isn’t alarm1 actually saying that i hit a endswitch? so when i do actually hit a endswitch, shouldnt I get the alarm 1 instead of the other message?
It depends on the exact sequence of what went wrong, when the controller detected the situation, and which error went out first.
Persuing the GRBL alarm doc may be useful:
You can experiment with limit errors by activating the switches manually while the laser is busy in the middle of the platform with the laser power set to zero.
Bonus fun: Make LightBurn layouts that deliberately move the laser head beyond the machine limits and see what happens when you try to engrave / cut them. When the Soft Limits switch is turned on, the controller will prevent that from happening, and LightBurn has a similar check; try various combinations.
No mechanical harm will come from this and you’ll get a better idea of what’s going on inside the controller and LightBurn.