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Robert . Payne
03-12-2017, 9:01 AM
Hey All,

Our laser stopped firing last Friday it powers up fine, and it attempts to run a job but absolutely no laser firing at all. It was working the day before without any sign of being faulty so it's a bit odd.

We took our tube to the local rep and it works fine in his machine so we eliminated the possibility of a tube failure. He figured it was firmware related so I took the tube back home and updated everything and even setup second PC from scratch just to ensure and still nothing firing.

The rep has a new motherboard on the way and said if I resolved it before it got here I could just mail it back and save the $1,000 or so it costs. The only thing is I'm not 100% convinced it's the motherboard, most electronics tend to fail either 100% or not at all and I took the motherboard out and there is *zero* evidence of any sort of faults, granted capacitors are hard to tell.

I thought perhaps part of the power supply is damaged, as if it's enough power to turn it on and drive most of the machine but not enough to get the tube powered up to fire properly?

Has anyone else experienced something like this?

Bill George
03-12-2017, 9:23 AM
If you leave a door open, in the past did the laser not fire or what? Thinking safety switch, But are you also sure you have not changed the color from RGB or CMYK in your project sent to the machine?

Robert . Payne
03-12-2017, 9:29 AM
If you leave a door open, in the past did the laser not fire or what? Thinking safety switch, But are you also sure you have not changed the color from RGB or CMYK in your project sent to the machine?

Hey Bill we're fairly certain it has nothing to do with software at this point. The interlocks report as closed and the red pointer (which is still there!) turns off and it runs motion along the cut paths just no laser power at all. Also using same job that had worked the day before.

I'm 99% confident it's either the motherboard or the powersupply, I'm just trying to avoid paying to replace the motherboard just to find out it's actually the powersupply!

Scott Marquez
03-12-2017, 10:46 AM
My untrained mind says "power supply", is there a trigger signal of sorts that goes from the motherboard to the power supply that you can check?
Scott

Robert . Payne
03-12-2017, 11:58 AM
My untrained mind says "power supply", is there a trigger signal of sorts that goes from the motherboard to the power supply that you can check?
Scott

I have no idea, I don't think so. As far as I can tell from what I can take apart easily it looks like tube's main power supply comes directly from the PSU and isn't routed through the motherboard.

I agree it feels more like a PSU issue, because motherboards normally fail all together rather than partially.

Glen Monaghan
03-12-2017, 2:46 PM
Try powering down the ULS, shutting down the PC, removing the USB cable from PC to the ULS, restarting the PC, then reconnecting the USB cable to rediscover the ULS, and see if the ULS fires again. Won't help to just cycle power; you have to force the PC to rediscover the ULS. This appears to be a random, infrequent problem with the ULS machines.

eduard rodriguez
03-12-2017, 3:14 PM
My laserpro do the same few months ago. In my case, it was the rj45 cable from the motherboard to the lasertube... bad conection. Cleaned up the cable conectins and worked again

Kev Williams
03-12-2017, 3:17 PM
Any chance your ULS guy could get you some troubleshooting diagrams? When my GCC started acting up, which included 'going thru the motions' but no laser firing, followed by not doing much of anything, I searched the 'net and found Jorlink had complete PDF diagrams online for this machine-- for the various power supplies complete with the output voltages from every plug, and for the motherboard complete with a diagram of what every single plug and wire is for. With this info and a basic volt/ohm meter I was able to determine that all voltages were spot on, so everything was doing what it was supposed to be doing--umm, so what gives??

--after scratching my head (and per some suggestions within the same PDF's) I pulled every connector and plug that I could, gave everything a shot of electronics spray cleaner, and once everything was back together, it ran flawlessly, and has done ever since... Cost me nothing but a buck's worth of dry cleaning fluid in a spray can :)

--the only way 'blind' troubleshooting works is if you have an identical twin to the machine nearby that you can swap parts and back and forth- like you did the the tube. Would your rep be willing to swap other parts for troubleshooting purposes? or is only the tube swappable? (not identical machines)...

diagrams with test procedures are worth their weight in gold and then some, if you can find them :)

In the meantime, do like me and ED above did, just start pulling and cleaning cables and connections, you may get lucky...

Glen Monaghan
03-12-2017, 4:17 PM
In the meantime, do like me and ED above did, just start pulling and cleaning cables and connections, you may get lucky...
Better, start by reinitializing the link as I described above... only one cable involved, and you don't even have to try to clean the contacts; just get the PC to rediscover the ULS and reinitialize the software interface. Good chance that will do the trick, based on his description of symptoms.

Robert . Payne
03-12-2017, 7:04 PM
Better, start by reinitializing the link as I described above... only one cable involved, and you don't even have to try to clean the contacts; just get the PC to rediscover the ULS and reinitialize the software interface. Good chance that will do the trick, based on his description of symptoms.

Hey Glen, we've done that already -- the rep even had us reset the EPROM and we've also used a completely new PC (I formatted and re-installed windows on it) just to rule out software issues.


Any chance your ULS guy could get you some troubleshooting diagrams? When my GCC started acting up, which included 'going thru the motions' but no laser firing, followed by not doing much of anything, I searched the 'net and found Jorlink had complete PDF diagrams online for this machine-- for the various power supplies complete with the output voltages from every plug, and for the motherboard complete with a diagram of what every single plug and wire is for. With this info and a basic volt/ohm meter I was able to determine that all voltages were spot on, so everything was doing what it was supposed to be doing--umm, so what gives??

--after scratching my head (and per some suggestions within the same PDF's) I pulled every connector and plug that I could, gave everything a shot of electronics spray cleaner, and once everything was back together, it ran flawlessly, and has done ever since... Cost me nothing but a buck's worth of dry cleaning fluid in a spray can :)

--the only way 'blind' troubleshooting works is if you have an identical twin to the machine nearby that you can swap parts and back and forth- like you did the the tube. Would your rep be willing to swap other parts for troubleshooting purposes? or is only the tube swappable? (not identical machines)...

diagrams with test procedures are worth their weight in gold and then some, if you can find them :)

In the meantime, do like me and ED above did, just start pulling and cleaning cables and connections, you may get lucky...

Kev yea this is what it might come down to, I don't trust myself a ton with a multimeter so I've taken the PSU unit to a certified electrician to get tested -- the rep told me the output voltage it should have off the prongs. If that test comes back as nothing is wrong I'm going to swap the motherboard and just hope that's all it is otherwise it may be a wild goose hunt to what part of the electrical system is broken.

Robert . Payne
03-13-2017, 8:45 PM
So we managed to get this fixed up!

Turns out it was indeed a faulty motherboard, I still find that extremely strange as electronics tend to not just have such a "partial" failure but the new motherboard has the machine humming along just fine.

In the end I didn't need to get the PSU checked but I just wanted to save myself $1,000 and the hassle of the motherboard swap if that was the issue.

Mike Null
03-13-2017, 9:05 PM
Glad you're up and running and thanks for reporting back to us.

eduard rodriguez
03-13-2017, 11:07 PM
Congrats!Happy too with my refurbished tube :) Installed 2 days ago. None stop working!

Scott Marquez
03-14-2017, 12:08 AM
I'm glad to hear you got it going. Is the motherboard repairable? I have had to send off circuit boards for welding equipment, when they were no longer available, I wonder if there is such a place for that board?
Scott

Robert . Payne
03-15-2017, 1:32 AM
I'm glad to hear you got it going. Is the motherboard repairable? I have had to send off circuit boards for welding equipment, when they were no longer available, I wonder if there is such a place for that board?
Scott

I have no idea, there's no obvious sign of damage on the board, we've already paid for the new motherboard now so hopefully we don't have to deal with this again for many years to come…

Lee DeRaud
03-16-2017, 9:20 PM
Not sure how I missed this thread and I realize this issue is resolved, but just a few observations for future reference:
1. Nowhere anywhere in this thread is it mentioned which model ULS is involved...and yes, it matters.
2. My ULS runs the laser tube off the same P/S as the motion system, so if the head is moving, the P/S is working. (Caveat: that may depend on the answer to #1.)
3. Yes, on some/all(?) ULS machines, the main power supply doesn't turn on until the CPU tells it to. (Or not: see #1)
4. On some/all(?) ULS machines, the main high-voltage circuitry of the laser tube is not turned on until the interlocks clear, at which point the red-dot pointer turns off. I've personally seen a laser tube put out the red-dot pointer, no problem, then (due to an internal short) pull enough current to make the P/S shut itself off when the door is closed. That may have been what fried the previous P/S that I had just replaced. (Again, see #1...are you sensing a pattern yet?)
5. ...no, I'm getting too tired and cranky to continue.

A whole bunch of people spent a whole bunch of time (and in OP's case, money) thinking about this. I'm glad the problem is fixed, although I'm not at all convinced that the original CPU is bad and/or that the physical act of removing/replacing it didn't fix the problem . A completely unnecessary lack of critical data sent the trouble-shooting process down some odd and illogical paths.

Robert . Payne
03-17-2017, 3:15 AM
Not sure how I missed this thread and I realize this issue is resolved, but just a few observations for future reference:
1. Nowhere anywhere in this thread is it mentioned which model ULS is involved...and yes, it matters.
2. My ULS runs the laser tube off the same P/S as the motion system, so if the head is moving, the P/S is working. (Caveat: that may depend on the answer to #1.)
3. Yes, on some/all(?) ULS machines, the main power supply doesn't turn on until the CPU tells it to. (Or not: see #1)
4. On some/all(?) ULS machines, the main high-voltage circuitry of the laser tube is not turned on until the interlocks clear, at which point the red-dot pointer turns off. I've personally seen a laser tube put out the red-dot pointer, no problem, then (due to an internal short) pull enough current to make the P/S shut itself off when the door is closed. That may have been what fried the previous P/S that I had just replaced. (Again, see #1...are you sensing a pattern yet?)
5. ...no, I'm getting too tired and cranky to continue.

A whole bunch of people spent a whole bunch of time (and in OP's case, money) thinking about this. I'm glad the problem is fixed, although I'm not at all convinced that the original CPU is bad and/or that the physical act of removing/replacing it didn't fix the problem . A completely unnecessary lack of critical data sent the trouble-shooting process down some odd and illogical paths.

Appreciate your input:

1. We're running a VLS 4.60, our rep knew this
2. As far as I could tell the PSU is split into two distinct units, one that powers the laser and one that powers everything else, as far as I could tell at least by following the wires
3. Somehow the CPU does control the tube's power supply, I'm not entirely sure how though
4. Red dot pointer was turning off and the interlocks were fine, the tube was totally fine as we unmounted it and took it to our nearby rep and tested it in his ULS machine and it worked like a champ so we knew from that point forward (and this was before I made this post) that the tube was not the issue.

I posted this because our rep and myself were unsure if the issue was the power supply, or the motherboard as he'd never experienced an issue where the motion system was fine, the tube red pointer worked but the tube wouldn't fire. I was mostly curious if anyone else had ever come across a similar issue. If it was the PSU I was about to waste $1,000 replacing the motherboard and if it was the motherboard I didn't really want to delay.

I had already re-installed all the software, flashed the EPROM on the machine and used a totally different PC to avoid any possibility it was perhaps the PC it was connecting to. Given that the software didn't seem likely and we'd already eliminated the tube as being faulty it really came down to the PSU or motherboard.

In the end it was the motherboard, probably the chip on it that controls the firing of the laser died but not enough to cause erroneous output on the machine itself or cause the whole system to just crash.

Lee DeRaud
03-17-2017, 11:13 AM
Appreciate your input:

1. We're running a VLS 4.60, our rep knew thisI have an older VL200. I know the smaller VL-series are configured the same way, not sure about the 4.60.
2. As far as I could tell the PSU is split into two distinct units, one that powers the laser and one that powers everything else, as far as I could tell at least by following the wires
I think if you look up the specs for the P/S, it only puts out one voltage, in the 48V+ range. (Unless ULS scraped off the labels, you can tell that by looking at it, no wire-tracing required.) On mine the CPU is powered from the USB.
3. Somehow the CPU does control the tube's power supply, I'm not entirely sure how though
On mine there's a short 2-wire cable from the CPU to the P/S that enables its output. Note, that cable does not power the CPU.
I was mostly curious if anyone else had ever come across a similar issue. If it was the PSU I was about to waste $1,000 replacing the motherboard and if it was the motherboard I didn't really want to delay.

I had already re-installed all the software, flashed the EPROM on the machine and used a totally different PC to avoid any possibility it was perhaps the PC it was connecting to. Given that the software didn't seem likely and we'd already eliminated the tube as being faulty it really came down to the PSU or motherboard.

In the end it was the motherboard, probably the chip on it that controls the firing of the laser died but not enough to cause erroneous output on the machine itself or cause the whole system to just crash.I'll take it on faith that the tech rep had you disconnect/clean/reconnect the cable between the CPU and the tube. Swapping out a $1000 part, unless it's clearly damaged or dead, is usually not the first step in troubleshooting a problem...unless of course you're in the business of selling $1000 parts.

In any case, my main point was that it was highly unlikely that anyone here could have given you any useful information without knowing the model laser you had. I'm glad you're back up and running, but that point stands.

Lee DeRaud
03-17-2017, 7:09 PM
2. As far as I could tell the PSU is split into two distinct units, one that powers the laser and one that powers everything else, as far as I could tell at least by following the wiresYou may very well have two separate but identical single-voltage power supplies to provide the required amperage: as I recall they install the second P/S with any tube over 30W. The motion system uses about 3A per axis with the steppers used in that system, but it never uses more than two axes at a time, so about 6A max. On mine the P/S is (conservatively) rated for 13A, so there's plenty left over to handle the smaller tubes. Yours can take up to a 60W tube, which needs more current.