Darkly Labs Community

Alarm lock error

Does anyone know what causes an Alarm lock error in the console window part way through a job, which then stops the laser and sounds a continuous buzzer sound? All the console window displays is ‘Alarm lock error’ repeated a number of times line after line, so not even a code number for at least a clue as to the cause.

When I run the job again it will sometimes error but at a different point in the cut. Other times it can run okay.

Along with lid trip switch issues I am having, I have spent two days and have not completed one job properly and have bin full of rejects!


I have had it happen twice on a big/long engrave on MDF. I put it down to tto much smoke in the unit and perhaps the ignition alarm thing kicking in. I tried the job again and a fair way into the job same thing. Removing the back electronics panel and giving the exhaust fan a thorough clean seemed to fix the problem. The fan was filthy as i do alot of MDF work.

Cameron, interesting I am cutting MDF with a large job which I have now broken down into four parts to try and reduce Alarm error code ocurrences. So far I have failed to fully cut a job to completion, wasted 11 sheets of MDF and fast giving up hope with this machine these days, I have no confidence in it anymore.

Will look at the fan and see if that needs a clean, aside from that the ‘Alarm lock error’ is next to useless for an end user message, it gives no clue as to the trigger, which the software must know to trigger the alarm in the first place.

Another way of attaking a big engrave is to do multiple passes at lower power or higher speed in order to reduce smoke produced. While you are giving the exhaust fan a clean, also clean the one on the the laser head (not the one on top)that cools the circuit board. Its on the back and down low. Mulriplw passes will also reduce the laser head getting too hot (not sure if that also is part of the lock alarm error)


They symptom you are describing is the over-temperature alert kicking in.

This is most likely caused by a build up of debris on the PCB behind the laser head, or a clogged PCB fan.

You can follow this article to resolve this problem:


Thank you both for the comments, I will try this out and see what happens.

Hey Domenic, it happened a long time ago with me and just providing some info for Martin. I keep all my fans in tip top condition these days. A brush attachment on a vacuum is a handy tool indeed.

Cameron, that seems to have done the trick, I had no idea there was a PCB fan at the rear, it was filthy. Cleaned extractor fan, in fact cleaned everything while at it. Ran the job, no alarm error, thank you for your help.

I have also doubled the speed and number of passes to try and help things, which so far has given me much cleaner cuts. I wonder if trebling speed and number of cuts would help in that it moves head before smoke can affect it?

Just need to sort the lid contacts out now so I don’t need a heavy weight and tape to stop them tripping.