It had been working perfectly until one day it stopped engraving mid project. It was still moving as if it was engraving but no laser. I noticed that it had stopped engraving because.I could hear a buzzing noise coming from the PSU. I could also see a little spark inside. I stopped the machine immediately and began to investigate.
After a fee hours and disconnecting, I opened up the PSU and and noticrd a bit of dust etc imside. So I gave it a gooooood clean. Put it all back together. plugged it in and tried again. Hey presto, it worked perfectly!! For maybe 3 hours.... when the same thing happened mid project.
The PSU wasnt making any strange noises anymore however. I took a look at the laser, and noticed that it was arcing near the exit when i tested it, regardless of power setting. I read up arcing issues and came to the conclusion that it must be the tube that has broken.
I have now replaced the tube. However, the same issue is occuring. Arcing at the exit end!!! The PSU still lights up when you press the test button on the PSU itself.
I have ordered another PSU but it doesn't arrive for a few more days.
Does anyone know if it is possible that it could be the PSU that is at fault? Or alternatively what the issue could be?
I am so behind on work now its laughable so any help would be greatly appreciated!
Absolutely it is the PSU. Probably dust (with a tad of moisture) caused the initial internal arcing. Cleaning it maybe took away the dust "paste" - but by then it was too late. The reason your tube is arcing is most likely because the PSU is now unable to supply enough voltage to get the plasma beam (laser beam) going (in layman's terms) so it will arc internally. Do not use it like this as the tube will get damaged.
Thank you very much for the info and for replying!
Well, I had thought that might be the case. Hopefully I havent broken the new tube already! It arrives tomorrow (hopefully!) so I will give it a go. I have bought a 50w psu for a 50w laser - is there anything else I should know about installing the PSU? Apologies, I'm new to all of this but want to learn.
Pleasure! The only thing to look out for really is that the wiring is the same. There will be 2 green plugs, 1 x 3-lead and 1 x 6-lead. the 3-lead is mains voltage (should say FG AC AC - or similar) and the 6-lead will have TH TL WP FG IN 5V - or similar. Not all of them will be used, but just make sure that the new power supply is in the same order - or change to suit.
So the power supply turned up today. Exactly the same model as the previous one. MYJG50w. I disconnected the old one and connected this one up to the 2 green plugs and the the laser tube. Unfortunately as soon as I turned it on, after about 2 seconds of the PSU powering up. It went dead. Nothing. I tested the fuse inside and its blown. I have no idea why.
The only thing I can assume after opening it up us there is one difference. The old one had a red switch between the laser light and first green port which you could switch between 230 and 115 (it was set on 230) - whereas tje new one does not have this ( please see attached images - new clean, old is the dusty one). That is the only difference that I can see???
Could this be the problem? If so can i solder the old one onto the new one as well as the fuse?
Or what else could be the problem. I have a headache now....
ps. my house runs on 220v, which is what the old psu was set to.
the new 220V power supply is missing the 110V / 220V selector switch
when the switch on the old power supply is in the 110V position
the mains input circuit will be re arranged as a voltage doubler to generate 310V DC from the 110V AC supply
with your 220V supply
the two power supplies are effectively identical
when the old supply switched to the 220V position
Yes I did also think the 220v psu should work, so I guess began to over complicate it in my mind. Regardless, I was up until 4am but I have gotten it to work finally! So I figured that the output was poor on the old PSU but the rest was still working, whereas the new PSU had blown. So I took off the flyback transformer from the new psu and soldered it onto the old one. Rewired it together and went for it. It worked, full power!
I just had to make sure all bubbles were out of the tube, and to then reallign mirrors due to the bumping about, but now its even better than before!
Thank you for all your help, hopefully this lasts!
Laser arcing!
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