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ArcticMyst Security by Avery

Got my 40 watt Co2 laser today, need HELP!!

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http://cgi.ebay.co.uk/Brand-New-40W...hash=item260266252426&_trksid=p3286.m14.l1318


I bought mine form the same seller, but for 80 GBP and 60 GBP shipping. not bad!!

I got it today, good condition, very shmexy, but one problem...

no manual... and the seller had NO IDEA what I was talking about

(
me: "I need to know how many kV and mA input this needs, AC or DC"
Them: "220v in, sorry, not know mA of"
)

so... I did a LOT of research, and spent some time on SAM's laser FAQ... and so I gather a small co2 laser can be powered by a neon sight transformer. I happen to have a bunch of those, around 15kV and 16~20mA.

BUT, then I came across this:
http://www.powerlabs.org/laser.htm


He had his hooked up to "a 15kV 20mA solid state neon sign transformer fed through a full wave voltage doubler"

... more research ...

So I gather he was running HIS 40watt CO2 laser at 30kV???

but then he says: "The transformer failed after 4 minutes run time, but it did work for the initial tests.

The current power supply consists of a 12kV 60mA 60Hz Neon Sign transformer fed through a full wave bridge rectifier. This feeds 720watts into the tube, which is excessive and will

shorten tube life, but does provide for some very impressive performance."



so that means he is running it off of DC???? but 12kV??? I am confused... Experience has told me that with lasers, be worried about the current, or in other words screw the voltage... but I DO NOT want to screw over a $300 laser tube.



also, My tube (as you may be able to see from the pictures) has some plastic/siliconlike/whatever tubing connecting two tubes together, and there are two open tubes which I am guessing is where the water attaches. can someone guide me as to what is going on?


help needed, thanks


regards,

amk
 





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I'm guessing the connected tube is just to circulate the water.

As far as powering it goes, I'm really not sure :(

BUT look on ebay, there is a guy who sells power supplies ready to go for co2 lasers with wattage specified (for example, it will be listed as a power supply for a 40W tube)
 
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720 watts!? I'm astonished the damn thing hasn't been blown asunder. The efficiency should be somewhere between 10 and 20 percent, so you should feed it no more than 400 watts. 200 with a top quality tube which I don't think that one is. (1000 hours is less life than your average incandescent bulb)

Specs. from a similar tube:

Trigger Voltage: 20KV
Operating Voltage : 15KV
Current: 18~22mA
 
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Heh, maybe I should make an offer on these medical CO2 lasers at my university. I wonder how little I could buy them for...
 
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I donno what to do... WIll it be okay on 15kV 15mA??


I really want to get this thing going
 
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amkdeath said:
I donno what to do... WIll it be okay on 15kV 15mA??


I really want to get this thing going

if you power the laser through a full wave bridge rectifier you'd be running the laser on pulsed DC, you'd need a large capacitor to smoothe the pulses into a constant voltage - but capacitors at 15KV are going to be highly dangerous and I'm not even sure if plain DC would work for a CO2 laser (I've never read up much on the actual operation on these lasers)
 
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These tubes typically run on ~12 KVdc. They may need upward 24 KVdc to ignite. That's why ballast resistors of 25K to 75K Ohm are sometimes used with your style PS. The newer ones on fleabay seem to have current control.
The HV is dangerous -- It will reach out to touch you. The beam can set a couch or whatever on fire. Be careful.

Mike
 
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well, before I read your posts, I hooked it up to 12kV AC at 30mA.

It hummed faintly, water cooling was running.... but nothing happened... no burning, no fires.

Are you sure it runs on DC?? Because there are no anode/cathode marks...


I guess Ill have to build a bridge rectifier !
 
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Spyderz20x6 said:
[quote author=amkdeath link=1217764604/0#4 date=1217793717]


I really want to get this thing going
I don't think kids should be playing with 40 watt CO[sup]2[/sup] lasers :-/
Be safe...[/quote]


its CO[sub]2[/sub] not CO(squared)

:)


regards,

amk
 
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amkdeath said:
well, before I read your posts, I hooked it up to 12kV AC at 30mA.

It hummed faintly, water cooling was running.... but nothing happened... no burning, no fires.

Are you sure it runs on DC?? Because there are no anode/cathode marks...


I guess Ill have to build a bridge rectifier !


You'll probably need more then 12kV to get it started, but that should be fine to sustain it. Usually around 20kV-25kV to get it going.

Now, as far as using straight DC, I'm really not sure :(
 
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well I fired it up again, no trigger to "get er started" but at 12kV it burned through newspaper, heated and charred glass, lit guncotton, and did some other stuff. But it doesnt seem quite like 40Watts. I know it may be because IM not triggering it.

will it be OK on AC? Ir should I get a rectifier? Its one of the OLDER Iron core neon Trasformers that are heavy as hell.



more help will be appreciated,


amk
 
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Well if it's burning anything then you got 'er started  :D

Again, I really dont know a damn thing about powering different co2 tubes, but I would really check out sams laser FAQ in the co2 section. I'm sure any information you need can be found there.

Here is a complete supply on ebay that says it can power up to a  40W tube max.

http://cgi.ebay.com/30w-20W-10W-CO2...52|39:1|66:2|65:12&_trksid=p3286.c0.m14.l1318

here's another one, it's a little expensive but looks like it would be perfect for your tube. Trigger is 26kV, operates on 22kV @ 20mA (24mA max) and is powered by 110v or 220v AC.

http://cgi.ebay.com/40Watt-40-Watt-...photoQQcmdZViewItemQQ_trksidZp1742.m153.l1262
 
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You'll probably ruin the anode running it on AC. The cathode is usually at the emitting end.
 
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The tube lights up sorta pink inside when running. You also need special lenses to focus that deep IR.

Miike
 
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amkdeath said:
[quote author=Spyderz20x6 link=1217764604/0#6 date=1217797892][quote author=amkdeath link=1217764604/0#4 date=1217793717]


I really want to get this thing going
I don't think kids should be playing with 40 watt CO[sup]2[/sup] lasers :-/
Be safe...[/quote]


its CO[sub]2[/sub] not CO(squared)

:)


regards,

amk[/quote]
Oh yeah...

My point is:
Just be safe...
 




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