View Full Version : Not sure if my tube is dying or not

matt heinzel
08-04-2016, 9:59 AM
We have 2 ULS PLS360 systems and the other day one of them stopped cutting through material. I ran some tests and it seemed to be rastering just find, but would not cut through even Flexibrass. I slowed the speed down bit by bit, and eventually I was able fully cut through on the horizontal lines but not the vertical ones.

Since we have two systems I swapped the tubes on the machines and it started to work just find. I'm just not sure if it is dead or not, our rep had me engraved a large piece very slowly to see if there was a change in the rastering over time and there didn't seem to be a change.

If we can't cut through flexibrass then we won't be able to efficiently make our trophy tags.
Any thoughts?

Mike Null
08-04-2016, 10:15 AM
It certainly sounds like your tube has deteriorated. I suggest calling Universal. They used to lend owners a power meter to confirm the output of the tube.

matt heinzel
08-04-2016, 10:24 AM
Thanks Mike I will do that.

Kev Williams
08-04-2016, 1:09 PM
My BIL's Gravo LS800 one day just suddenly lost power. Our rep did a power test, and found his 40w tube was putting out exactly 20w...

I don't completely understand the dynamics of metal tubes but I understand they're powered by 2 separate supplies within the tube's enclosure, including 2 capacitors. Some research in this forum has indicated that it's not uncommon for one of these capacitors to go bad. This is what happened with the LS800. The tube will otherwise operate normally, but at half power. The LS800 has been working at half power for over a year now with no other issues.

The "then the other day it stopped cutting thru material" is indicative of this problem; worked fine day, not the next. I've been fortunate in that (knock on my head) I haven't had a tube go bad or lose power, but it sounds logical that a tube simply losing power would do so gradually...

Just my 2c .. :)

Scott Challoner
08-04-2016, 1:23 PM
I recharged my tube last year and was told they typically don't lose power gradually but go to about half power rather suddenly, which is what mine did. My rep is pretty close so I grabbed his meter and verified. I also measured some voltages on the power supply to rule that out. Get the meter but I would check the lens, mirrors and alignment in the meantime. See if they have an exchange program. I was able to get a refurbished tube relatively quickly and then sent mine back in exchange. It beats sending it in and waiting for it to get recharged.

Evan Requardt
08-04-2016, 1:34 PM
In December of last year I noticed a loss in power. If I increased the power, lowered the speed and went over the same spot multiple times, then I would get normal results. It bothered me that I had to do all of that just to get the same results though, so I too checked the voltage from the tube and it was perfectly fine. It turned out that one of my mirrors was extremely dirty and that was effecting the lasers output. I'd check your mirrors as well.

matt heinzel
08-04-2016, 1:43 PM
Thank you for all of the responses. I think we are doing an exchange with ULS.