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Co2 laser powered by zvs driver?






Benm

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Capacitors are a different story indeed. The good thing is that you can hook them in series quite easily, and when you use a voltage multiplication ladder, they are arranged for it by default.

Some flybacks have a voltage tripling ladder installed already and provide dc output - look for any of those!
 
Joined
Jun 24, 2010
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Thanks for the tips :)
I have a home made 10nf (ish) capacitor somewhere made from a vodka bottle and some foil which i normally use whenever i want smooth DC from a flyback transformer. I think my transformer has some internal capacitor, i have to discharge it before i touch it or i get a fairly nasty shock. Would adding a bridge rectifier help considerably? Right now my power supply is only half-wave rectified because of an internal diode.

I think I'll work on getting the tube up to full power before i worry about a smooth power supply. i can only get up to about 6ma right now. The power supply im using for my zvs driver can only do about 5A at 24v, from the looks of things i need at least double that.


Any time you have two conductors, such as the secondary winding and the primary winding or the core separated by an insulator, you have a capacitor. I've been zapped a few times by the stray capacitance of flyback transformers, once after it had been unpowered for more than 24 hours. It doesn't take much capacitance to give a good zap when it's charged up to 20-50kV.
 
Joined
Jul 4, 2008
Messages
2,499
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Thanks for the tips :)
I have a home made 10nf (ish) capacitor somewhere made from a vodka bottle and some foil which i normally use whenever i want smooth DC from a flyback transformer. I think my transformer has some internal capacitor, i have to discharge it before i touch it or i get a fairly nasty shock. Would adding a bridge rectifier help considerably? Right now my power supply is only half-wave rectified because of an internal diode.

I think I'll work on getting the tube up to full power before i worry about a smooth power supply. i can only get up to about 6ma right now. The power supply im using for my zvs driver can only do about 5A at 24v, from the looks of things i need at least double that.

I seriously suggest not using lossy capacitance. There is little chance you have 10nF capacitance from a Vodka bottle. I'd say more like 5pF (if) you are lucky.
Also with load and breakdown from corona and Ozone production, glass capacitors can get quite hot and fail.

With smaller HV caps being fairly cheap, I'd strongly suggest possibly looking at a doorknob cap bank for what you're doing. You aren't pulse discharging it so one of these puppies will do.
 
Joined
Jun 24, 2010
Messages
243
Points
18
I seriously suggest not using lossy capacitance. There is little chance you have 10nF capacitance from a Vodka bottle. I'd say more like 5pF (if) you are lucky.
Also with load and breakdown from corona and Ozone production, glass capacitors can get quite hot and fail.

With smaller HV caps being fairly cheap, I'd strongly suggest possibly looking at a doorknob cap bank for what you're doing. You aren't pulse discharging it so one of these puppies will do.


These are super cheap and work fine, I have some

High Voltage Ceramic Disc Capacitors

You can wire two in series to double the voltage (capacitance is halved) or parallel to double the capacitance, voltage rating stays the same.
 
Joined
Feb 28, 2011
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Any time you have two conductors, such as the secondary winding and the primary winding or the core separated by an insulator, you have a capacitor. I've been zapped a few times by the stray capacitance of flyback transformers, once after it had been unpowered for more than 24 hours. It doesn't take much capacitance to give a good zap when it's charged up to 20-50kV.

Ahh, i never thought of it that way, it always suprises me how many things act like capacitors when you dont expect them to.

I seriously suggest not using lossy capacitance. There is little chance you have 10nF capacitance from a Vodka bottle. I'd say more like 5pF (if) you are lucky.
Also with load and breakdown from corona and Ozone production, glass capacitors can get quite hot and fail.
Im pretty sure its at least a few nf, it holds quite a bit of charge compared to some low value (<10nf) HV capacitors ive used for other experiments before. (then again, im terrible at remembering values for things, so it could very well have been pF) I'll look into getting some proper capacitors soon, i haven't botherd with my homemade ones incase they melt or shatter, or find a new way to fail rather spectacularly.

These are super cheap and work fine, I have some

High Voltage Ceramic Disc Capacitors

You can wire two in series to double the voltage (capacitance is halved) or parallel to double the capacitance, voltage rating stays the same.

I'll look into those, they look perfect for this type of thing assuming i stick a few in series. Cheers :)

Oh and while im at it, thanks everyone :D You've helped so much so far, this forum is great :)
 




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