473nm blue module overheating (big scare!)?

[Schrecken_Licht]

I mentioned this briefly in the multi-media section, but here's a bit more detail. I have a 100mw (actually puts out about 130mw avg.) 473 blue Lasever module, and I have run it off and on ever since I've had it (for almost 2 years), but never more than about a half-hour run time.

Tonight I had it set up for a time tunnel in my garage for a Halloween display.  It was cold outside (well, not real cold but around 50-55F).  Well, it ran fine for a while, maybe almost an hour, until the beam began to get dimmer (there were some kids hanging around and one asked which was more powerful, the red or the blue, and that drew my attention to it) and suddenly it just winked out.  A few seconds later, it came back on, nearly full power, but winked out again. Then I unplugged it, and the case was very warm (not so hot you couldn't touch it, but pretty warm).  I left it off for the rest of the evening, until I shut everything down.

After it had cooled off, I plugged it in and luckily it came on and seemed to work fine.

Anyone have one of these Lasever (or similar) modules? I thought these things were for continuous duty, as they are designed for laser shows and such.  I have had the case get warm before, but it never cut out like that. I was afraid the thing had died on me.... Why would it overheat like that, especially if the air temp is below what is considered "room temperature"?

 

[digital_blue]

I have found that DPSS laser don't operate well in cold weather. My greenies have shut down completely in 5 degree Celsius weather. They usually come back to life after warming up again...

 

[thesk8nmidget]

sounds like you may have had a tec problem.

these should be capable of cw and 55 degrees temp doesnt sound all that bad. especially if the unit was so warm to the touch. my 500mw green can run for hours and hours and its always room temp.

my guess is something is not cooling correctly at all!

 

[MarioMaster]

yeah I agree that there could be a problem with the TEC - the 200mw green I has really bad output (65mW or so) if the TEC is not powered

in mine the old TEC actually broke and wouldn't cool anymore, so I had to replace that

you could also have a bad thermistor resulting in the tec not turning on when it's needed

 

[Xplorer877]

I have found that DPSS laser don't operate well in cold weather. My greenies have shut down completely in 5 degree Celsius weather. They usually come back to life after warming up again...

"Usually"!!? Can running you laser in cold weather can damage lasers permanently?!

 

[Schrecken_Licht]

yeah I agree that there could be a problem with the TEC - the 200mw green I has really bad output (65mW or so) if the TEC is not powered

in mine the old TEC actually broke and wouldn't cool anymore, so I had to replace that

you could also have a bad thermistor resulting in the tec not turning on when it's needed

How would I know that it's bad? What do I look for?

 

[digital_blue]

"Usually"!!?    Can running you laser in cold weather can damage lasers permanently?!

I'm not sure if running in cold weather damages it permanently. Running a laser at extreme temperatures could cause contractions and expansions which lead to misalignment... My lasers emit IR after running at cold temperatures but they usually start working properly after a few minutes at room temperature. I've had lasers running at TEM01 for several days after having run them in cold weather before they "fix" themselves...

 

[maxkillz]

my alpha hates cold weather...it sucks to live in michigan :'( i wanna go back to daytona beach :-/

 

[Ace82]

Well, I don't know if it's such a huge deal :-/

Some are arguing that it was because of the cool night, while you think it's because the unit over heated, if it did overheat I don't think it would have anything to do with the cool environment. I know the crystals are very temp sensitive and that it could shift modes easily once they get too warm, I wouldn't think it's the diode as long as the TEC is effective on that part.

I believe that the crystals just became over saturated, even with the TEC, maybe the cooling is not sufficient for the power? Maybe the crystals are over efficient for it's rating, maybe it would be sufficient for 100mW but not 130mW? Once the unit has a few minutes to cool, it should go completely back to normal. For running at long periods of time, maybe you need to either lower the current, or upgrade the cooling.

 

[MarioMaster]

How would I know that it's bad? What do I look for?

I wouldn't be worried - if the laser still powers up and runs fine it was probably just a temperature alarm and it shut down to protect itself.

 

[Schrecken_Licht]

I powered it up again tonight, and it seemed to be OK, but I only let it run for a few minutes. It wasn't super-cold Halloween night, maybe 55 degrees F. Actually, oddly enough - my yellow pointer (having been stored in that cool garage all day) powered right up - no dim green dot or anything!

I guess with the blue I'll have to limit the running time for now. For next year I'll plan on using my single-line argon instead. At least it is still putting out a beam - I had a huge moment of dread when that thing kicked off - at least until I let it cool and powered it up again!

 

[FrothyChimp]

The lasever type units require additional heatsinking to operate greater than 10-15 minutes or so depending on output and wavelength. The drivers have over-temperature circuitry and will shut down the system on high temp conditions. Since they are designed as OEM components you need to add the heatsinking (to both the laser head and the driver).

 

[diachi]

You could add a heatsink and additional TEC that would probably ensure that it doesn't overheat. there are plenty of TECs that would suit you on eBay. Try it with another heatsink first though and see how it does.

-Adam

 

[Schrecken_Licht]

The lasever type units require additional heatsinking to operate greater than 10-15 minutes or so depending on output and wavelength. The drivers have over-temperature circuitry and will shut down the system on high temp conditions. Since they are designed as OEM components you need to add the heatsinking (to both the laser head and the driver).

Thanks for the info. I figured I had either a defective unit from day one or it wasn't designed to run for long periods of time as-is. Now I know which it is.

 

[dar303]

I thought these things were for continuous duty, as they are designed for laser shows and such.

Using them in lasershows isn't really CW use since they are blanked/modulated at several kilohertz rate.
I think it may be a cooling issue as someone pointed out, attach it to a heatisnk or metal baseplate and it should be fine.

 

[thesk8nmidget]

[quote author=Schrecken_Licht link=1225505059/0#0 date=1225505059]
I thought these things were for continuous duty, as they are designed for laser shows and such.  

Using them in lasershows isn't really CW use since they are blanked/modulated at several kilohertz rate.
I think it may be a cooling issue as someone pointed out, attach it to a heatisnk or metal baseplate and it should be fine.[/quote]


yes but they do need to be capable of cw for hours of use.

i know laser wave tests all their new designs by leaving them on for over 1000 hours really just until they die