VLS 6.60 sometimes turns off when lids are closed

[Will OBrien]

My VLS 6.60 will sometimes shut down immediately after I power it up - after a couple of tries, it'll turn on.

I've noticed that it would shut down when I close the lid. Thinking that a cable was getting jostled, I closed it very, very slowly several times. The laser still shut down.

I'm suspecting that perhaps I have a floating ground or something. I've had the same symptom even when I shut the front of the laser.

I'm thinking that it's the interlock circuit causing funky behavior (thus the suspect ground)

Any thoughts on this? This is a used laser that I just purchased, so I haven't checked with Universal... yet.

[Keith Colson]

With my garage door remote killing an engrave job yesterday, I was thinking the same thing about a floating ground, that makes a good antenna. I will have a look at my machine and see if there is anything obvious.

I have all my equipment connected to the same local electrical ground so as not to rely on the grounds going back to the switch-board. The compressor is electrically very noisy too and the ULS is happy with that so my noise is not entering via the mains.

Cheers
Keith

[Keith Colson]

Hi Will

I did some measurements on the VLS6.60 today, just a quick look. By just measuring from one magnetic sensor I established the following

1) There are 4 normally open interlock magnetic reed switches that are in series. Two on the front door and two on the top lid.

2) The interlocks at one end read ground and the other end reads 12 volts. I put my resistor wheel in and established the 12 volts is pulled up by approximately 4.7k ohms. The switching threshold is around mid rail of 6 volts.

If you are concerned about the magnetic interlocks there is an easy test. When any of the four interlocks is opened you will see the read beam come on. You can defeat the magnetic switches easily with a magnet if you want to "try stuff" but don't run it with the doors open. I have made an interlock defeat part that is laser cut, you can get it here (http://www.sawmillcreek.org/showthread.php?221022-Unversal-Door-Override-Part) http://www.sawmillcreek.org/showthread.php?221022-Unversal-Door-Override-Part

e.g You could wiggle each door and see if the red laser comes on. I think grounding on this circuit is not a concern because when all the interlocks are closed the full line is pulled to ground meaning that this circuit is now fully grounded.

This does not solve my problem which I will continue to look into, good luck

Cheers
Keith

[Will OBrien]

Just to be clear - In my case the entire laser powers down, not just shutting off the cutting beam...

I'm thinking of trying a power conditioning power strip to see if that settles it down. I too use a strip to power the PC, laser and my air filter. My compressor is on another circuit, but it's isolated by the air hose, so I'm not concerned about that being the source.

[Yuriy Karpov]

I'm having the same problem with my 4.60. It's very intermittent, I can't get the pattern when it's happening. Although in past 2 years I have never experience this issue. Could this be the software?

[Keith Colson]

I never plug any industrial equipment into power strips, they are generally not up for the job. Seeing as I have an electrical license I installed power points for each component so its clean and only one plug per outlet.

A power conditioner probably won't do you any good. They typically just stop voltage spikes and I would be surprised if the VLS does not have metal oxide varristors internally, which is all a power conditioner has. They are more a gimmick but they do work on cheap gear during a lightning storm.

I am wondering if I should try a firmware update next.

Cheers
Keith

[John Volkmar]

VLS units that turn off suddenly are usually a result of not configuring the Power management settings correctly ( Disable USB Power suspend in Windows ), or the PC/cable you are using. I would confirm the USB Port status 1st then try another PC/cable. Make sure you get the Adjusting USB Suspend settings document from Tech Support. If the issue persists after the above, you need to replace your CPU.

[Keith Colson]

Hi John

That is an interesting. When Windows puts the USB into the suspend state it will also put the screen to sleep in a standard configuration. If this was my problem I think I would see the screen switch off at the same time. Worth trying though.

Cheers
Keith

[Bill George]

Hi John

That is an interesting. When Windows puts the USB into the suspend state it will also put the screen to sleep in a standard configuration. If this was my problem I think I would see the screen switch off at the same time. Worth trying though.

Cheers
Keith

Why would it go into power saving in the middle of a job? Sounds like a loose connection someplace in the machine or Emergency stop system.
Power strips. There are good ones and bad ones, I have my machine on one along with the air pump, exhaust fan and water pump. One click and its all on, except I turn the machine by hand. I paid $20 or so for the good power strip and it was made for Industrial use.