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ArcticMyst Security by Avery

40W Co2 laser gun burning wood

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Nov 20, 2015
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What is #1 and #2 ?
What%20is%201%20and%202_zpsubfcag3l.png


1 is a 150W dc-dc circuit output 26.2V
2 is two dc-dc circuit output 10v and 3v
 
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Joined
Nov 20, 2015
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What is #1 and #2 ?
What%20is%201%20and%202_zpsubfcag3l.png


Is #1 your DC to DC to make 26.2 volts to drive the ZVS? How about starting voltage?
I am thinking about tube longevity, if you limit voltage then like you say, no need to care about current.
Is it starting on just the run voltage, do you have it limited?

i think if the voltage on the tube is correct,then current is correct,like I=U/R
i found if i increased the input voltage funther like 28v,this output power is not change.so i set it on 26.2v
i don't know what is the right voltage and right current to drive the tube and how to limit it, just setting the input voltage ouputing max power.
i have buy a commercial 40w driver to compare the max output power.
 
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Joined
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I couldn't get your link to load, but specs on another 40W tube were 20k volts running and 25k volts to start, at 15ma, you may be overdriving it and the problem there is it may not last.

So #1 and #2 are your DC to DC to drive your zvs and the other are your 5v and 10v batteries for your pump and pointer laser?

p.s. I like the build, but I would limit the current.
 
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I couldn't get your link to load, but specs on another 40W tube were 20k volts running and 25k volts to start, you may be overdriving it.

So #1 and #2 are your DC to DC to drive your zvs and the other are your 5v and 10v batteries for your pump and pointer laser?

only one battery,three dc-dc ouput 26.2v 10v 3v.
#1 to drive zvs
#2 to drive pump and pointer.
 
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I can not get the link to load where you buy the tube for 70 dollars,
can you post the place where you buy that tube.

I can get it to load now, but it's all in Chinese LOL, I see the USA flag and used the Us site, but still it's in Chinese, it does say 18w-200w tubes and 69 dollars, but I am not comfortable trying to order when I can't read.

A bulk order could be resold on ebay, hmm.
 
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I got some ZVS drivers in today and flybacks, I also have boxes of salvaged flybacks as well and I can see this refined and lensed into a fun leaf zapper.

These zero voltage switches use high freq caps, and mosfet transistors, and the big inductor is the ferrite doughnut, this limits current. I could reproduce this circuit but it costs less to buy them ready made. Different sizes are available, likely running around 100,000 cycles but I can convert to DC is that's better for the tube, I suspect it would be.

SANY0439_zpszfngcbai.jpg

SANY0440_zpswm1dorcd.jpg



This is the new primary, 4 turns each side, lol, hey it works.
SANY0441_zps6vpea783.jpg



ZVS120115a_zpswmrin0tc.png


I plan to have a start and run circuit because I want my tube to last, although a series limiting resistor may do.
I'm new to gas discharge lasers so I'm going to read up on what the tubes like as far as power and work out what will yield the best longevity. I can make what ever power it needs.

Yes I will build a compact cooler/pump setup, this will be fun.
I may split a 4 inch wide length of pvc and build a cooler fan to mount in back, and have the top/bottom hinged for service, battery changeout.

Can anyone recommend a good c02 tube, or more important what brands are no good?

A compact tube or one with excellent raw beam specs would be great.

YES I will do a lot of reading, but
Any ideas are appreciated.

The beam quality and divergence look very workable in rabbits video, ebay has lenses even, this is more eyesafe as far as diffuse reflections but even clear polycarbonate safety glasses should protect from that, I still will get proper glasses for 10um, 10200-10600nm.
 
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The vast majority of flyback transformers have built-in rectifiers. They are already DC output. You're gonna want bigger heat sinks for running a laser. What are you using for power input?
 
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Yes you are correct, it is putting out DC.

I am powering it with a desktop supply, I plan to use a DC to DC voltage limiting driver like rabbit did, but I have to make sure it won't spike on start up/shut down, I've run into that before. I may switch the output from the DC to DC driver powering the ZVS and always break the circuit before turning the DC to DC on or off.

My probe is a fluke 80k-40HV it's meant to work with a 10 meg ohm meter but mine is a billion.

When I add a 10 megohm resistor across the input it makes no difference

I think I am getting a 1000 to 1 reading.
If so
I am getting 29k volts out DC at 27 volts in and 780ma, I have not measured the current yet, but playing with it for 5 minutes drawing an arc the only thing hot is the wire end that's drawing an arc. The transistors feel cool to the touch.

What I wonder is if I limit the voltage to the laser tube can it still overcurrent?

Can I get away with limiting the ZVS input voltage?

I really don't know about gas lasers, I need to look at a proper power supply and reverse engineer it, I'm still in the planning/maybe about to kill a tube phase.

p.s. the same fluke probe reads 120v ac house voltage as .120 so it is 1000 to 1

SANY0450_zpspt5yowzr.jpg


SANY0444_zpsknkq4df2.jpg


SANY0448_zpsthvxlbyz.jpg


SANY0445_zpssgpdtseu.jpg
 
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Think of it as having a series resistance. It's only 29kV open-circuit. When you load it down, the voltage will drop.

You can safely put your ammeter in series with the high voltage to measure the current (of the arc, or of the tube current etc.) Just don't touch it while it's in operation unless you earth-ground it. Ammeters are electrically the same as a small length of wire.
 
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Are you living single? You must be, I see you are still alive after burning that door so much!
 
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Good lord this is awesome. How long does the battery last and what's the duty cycle?
I might have to revisit the idea of a co2 laser. You've inspired me. + rep
 
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