Sorry this is so long, but details and troubleshooting, etc.
My controller is Ruida RDC6442G-B and my power supply is a ZYE MYJG 100W
(like this: https://www.cloudraylaser.com/products/cloudray-100w-myjg-co2-laser-power-supply-with-lcd-display )
I just yesterday tried my first test after installing a new tube. First task is to scribe a light line to frame some stock. After seeing unexpected (full) power on the 0-30W meter, I then programmed 20% power first, then 10%, then 1% just to see what would happen. No love - it’s always full on. I’m getting 100% power output no matter what power I program in Lightburn. I’ve set my minimum power to 1% just so it stays out of the way, and I’ve checked my vender machine settings and maximum and minimum power are at reasonable levels (99% and 10% respectively). But no matter what I send to the machine, once the laser fires, it’s always at 100% (about 23W).
I did tweak my power supply adjustment pot because it was capped at about 15W and I turned it until it would just reach 23W (because from what I could find, that’s a relatively safe power for my 80W tube). I did have to unplug and re-plug the two green terminal plugs to the power supply (so I could access the pot through the hole), but I would think that if that went bad, it would either fire or fail, not just fire 100%
Other than that, the only mods I’ve done are the physical replacement of the tube.
I’m pretty new to Lightburn, so maybe there’s another setting I’m missing? I’m assuming if you select a layer and set “maximum power” on the popup window for that layer, that’s the power that should be firing in operation?
All I can guess at now is it does indeed seem like probably something got jiggled or something while I had the power supply unmounted from the machine enclosure while I was trying to set the power output pot. Even if I set the maximum power output very low on the controller panel and do a pulse, it still puts out full watts. I have checked all the wiring and it all seems good.
Either I lost the PWM signal from the controller somehow (seems unlikely since I didn’t mess with anything on it other than temporarily unplug the green terminal plug from the power supply), or while I was messing with the power supply, I somehow fried or shorted something fragile so the PWM is always 100% now.
I did use a ceramic screwdriver to adjust the pot, so I didn’t short out anything with the tool, but maybe something else could have happened?
The power supply output pot seems to work fine as it does limit the output of the power supply (I have lowered and raised it a few times now and it responds predictably). But when I try to fire it from the controller, it’s getting nothing but 100%.
Any ideas what I should try next? I have an oscilloscope but I’m kinda green on using it. But I could maybe verify that I’m getting a signal from the controller I guess. Could maybe draw up a test for maybe 5 short lines with varying power on each and see if the pulse width is changing.
Is there some kind of procedure I could do to check things out? I wish I knew more about this, but I guess I might after trying to work this out, whether successful or not.
It would be helpful to at least know what kind of signal the power supply is expecting so I can check whether the controller is outputting something appropriate.
Any help here would be appreciated, so thanks in advance for anything. I’m feeling a bit lost & overwhelmed. Just not sure what to do.
By the way, I do know not to connect my scope to the output that fires the tube, in case anybody got spooked there. I would expect the controller PWM is 5V or at least something that won’t damage the scope… or me.