Lost connection repeatedly…

I’m very new to the laser world, and am having a very hard time getting my laser to complete a cut. It loses connection, states “Connection Lost” in console. I’ve replaced the USB cable, and have also changed outlets with no further success. This is a new problem that has just started. I’ve had the laser for about a month and have successfully made cuts no problem. Now everytime I start a cut, it loses connection before it can begin, or half way through the job. What do I do?? Help!!

I had this problem, relocated my USB cable away from other stuff and problem went away.

I’m not sure what you mean by that. My usb cord isn’t really next to anything. It’s running directly from my laptop to the laser.

I moved my air pump and it was too close to USB cable, moved my cable about 2" away and fixed problem. It does not take much for a USB cable to pick up interference.

i dont really have anything that close to the machine. I’m beginning to wonder if the machine has something wrong with the usb port. i cant complete a job and get some messages in the console screen…any thoughts about that?

This is what the screen reads when it stops…

Connection lost

Stream completed in 5:29

Grbl 1.1h [‘$’ for help]




Target buffer size found

The next most likely cause is the driver for the USB port not loading correctly, to check this if using Windows go into control panel then device manager and Ports and see if there is one with CH34x in the name, if not try restarting windows. this driver is often corrupted after loading (no idea why) so even if it is showing a restart never hurts.

The error dialog points to a USB stream in an interrupt-wait state on the software side while the USB controller side has been terminated.

I do not know why, but turning off WiFi on my computer (I use USB only for LB) appears to have stopped 95% or more of the streaming interruptions.

There is a suggestion somewhere in this forum to change USB settings…I think the setting was to remove USB connection termination upon timeout???

I followed that suggestion and it helped…if I can find the post I’ll append it here…but turning off my WiFi was the ticket for me. I have suspicions about certain OS vendors and their snooping/nagging practices, but. :joy:

Lots of reading can be had by searching “USB timeout”

Quite sure you can find the forum-suggested how-to for changing the settings.

I’ve turned off Wi-Fi and Bluetooth connection for the laptop. Same problem is still happening. Occasionally the project won’t even officially start before it loses connection. The laser will begin to get into position and then lost connection. There doesn’t seem to be a rhyme or reason for it. I’m so frustrated.

Due to varying amounts of time before losing connection, it is sounding more and more like interference, when you swapped cables were any of them shielded cables ? It could also be a lose connection on either the USB port on the computer or laser, they do ware over time, is there any wiggle in them ?

Does your cable have chokes installed? Or, as mentioned a shielded cable might help. In Windows, there is a “power saving” setting for USB ports. Sometimes, depending on how you have power settings, the USB goes to sleep. Here is a cable with chokes:

I have and older Ortur Laser Master 2. There are a number of complaints like yours. Ortur devised a cable to replace the one that came with the unit. The difference being that the new cable grounded the unit. However that fixed mine but I also discovered adding Ferite modules to the USB cable helped. One user said power the laser on a dedicated electric circuit. Or nothing else plugged into the same circuit.

I don’t know if this will be helpful but i had similar problems. I had the Laser connected to a usb3.0 port. I moved it to a 2.0 port after a few weeks and the problem vanished. I do still get occasional laser stops, not sure what causes that but the frequency of communication loss has dropped verry substantially. I also turned off the USB sleep timer in windows.

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