Detect movement, terminate laser engraving! Acceleration fluctuation

I’m consistently getting an error when I start engraving something at speeds beyond 5mm/s that read like:

Starting stream
Layer C00
Detect movement, terminate laser engraving!
Acceleration fluctuation:260
Reset Grbl.

The behavior I’m seeing is the laser barely moves and then immediately stop without achieving anything. This happens 90% of the time, sometime’s it does start but then stops midway:

Also when I have engraved quite slowly it still gives the following error:
Reset while in motion. Grbl cannot guarantee position. Lost steps are likely. Re-homing is highly recommended.

Also when I stop the frozen job the error it gives sometime’s is:
G-code locked out during alarm or jog state.

Here is some example g-code:
; LightBurn 0.9.19
; GRBL device profile, current position
; Bounds: X0 Y0 to X55 Y54
G00 G17 G40 G21 G54
; Cut @ 25 mm/sec, 50% power
; Layer C00
; return to starting pos
G0 X0Y0

Just want to note I have test the machine out sitting on a cement flaw and I still get this error

I was able to fix this by setting $33=1000 for people’s information if other’s have a similar issue

Please note: For those unaware I believe that this is essentially turning off the g-shock sensor by increasing its limit drastically, which is a safety feature. Please keep in mind that this will likely mean that the machine doesn’t have protection of shutting down if it falls or tumbles.

Can some please guide me to resove the below issue .

I recently bought Ortur laser master 2 pro , for the very first trial the machine shook violently and I had to emergency stop it after that I am having trouble in executing any job.

In the second trail it worked for few seconds than stopped . Now it just do homing and we cant even do Framing. Following are errors log.

OLF 152.
[MSG: Flame detector active,Ambient infrared value:4086]
Grbl 1.1f [’$’ for help]

G-code locked out during alarm or jog state

I had this problem too, just adding what worked for me, in case it helps anyone else struggling with the same.

I had to change the $262 value to change the G-shock threshold.

I ended up disabling mine entirely by setting $262=0. This means I will not get an alarm if the laser cutter falls, but I never leave it unattended while in use, so this is fine for me, but please take the time to consider this as you are disabling a safety feature. Please note, too, this fix only works for firmware 1.78 (or, presumably, later), so you might need to update your firmware first.
If you wish to disable your sensor entirely, go to the console window in LightBurn (while you are connected to your Ortur) and type $262=0 and hit enter.

If you’re having trouble with this value ‘sticking’ (for example you get this error again after re-starting/resetting your machine, or after changing firmware), you can also add this command to the start GCode for your laser (Edit>Device Settings>GCode>type it into the ‘StartGCode’ box>Hit OK). This will mean that it will turn off the sensor before every job that you run, so it’s sort of a backup. Side note, but it’s also handy to add $H to this box too, to home your machine before each cut, in case you haven’t got it in there already.

You also don’t have to entirely disable the shock sensor, you can just change the threshold value, if you wish (this should work in earlier versions of the firmware, too). You can check the current threshold value by typing $$ into the console in LightBurn (which will give you a list of all current values for all settings for your connected machine). From there you can set it to a different value by typing $262=[number] (e.g $262=500 to set it to 500).

Here’s a list of all the commands for ortur and their default values (I had a hard time finding these, so I’m posting it here in case it’s handy for others!).

Hope this helps someone else!

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