Laser trouble

[stuart rollinson]

Hi, I have a Chinese laser machine (2 years old with light use, approx 10 hours a week) with a 80w Reci tube, my problem is for the last couple of weeks the power of the laser has dropped, on first start up in the morning when pressing the test button at 80% will barely mark the wood but after 10 seconds it starts to improve, but then takes a couple of seconds to improve second and third time around.
I can't see any arcing on the red wire, I was wondering if it's worth replacing the power supply? tube? or controler first. Any help would be appreciated.

[walter hofmann]

I would replace the tube first because that's the part what goes first seldom the powersupply and the controller has not much to do if the power goes down.
greetings
waltfl

[Graham Facer]

Well - that's the reverse of what mine seemed to do (it would show more life on a test and decrease on run time) but that said, I'd get both a power supply and a tube. The power supplies seem to be consumables by all accounts so a spare after a few years is a worthwhile investment. If you have the time, I'd get the power supply first as if you swap it out only and the existing tube is the same, the power supply can sit on a shelf for a few years and not be the worse for wear.

If the power supply is not the issue, then I'd check the controller - but that's pretty easy as it just does a 0-5v (or less - depends on the controller) to the laser which tells the laser supply if it is 0-100% power based on the voltage. Not the best explanation but look basically one wire is always one voltage from the controller to the Power supply and the other only shows a voltage when the laser is firing. The ratio between the two is the %. Likely its fine anyhow.

Then I'd get a new tube.

If I was short on time, I'd get the tube and power supply and hope it was the tube by switching that out first and holding on to the spare power supply for the next time you have to diagnose an issue.

I basically just went through this but luckily we had a spare power supply.

Graham

[stuart rollinson]

Thank you Walter and graham, it was the tube that had given up, fitted a new tube and it is running perfect.