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WTB: 120V whitelight ArKr

Sta

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Hello folks,

Title says it all, I'm looking to buy a complete whitelight ArKr that works on 110/115/120VAC. If you've got one of these units and you're willing to sell it, please PM me or comment below.

:)
 



ultimatekaiser

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There are none. Even the smallest I've seen that I can think of all require 220v. The voltage drop is too large across the tube to sustain the arc at 120V. Krypton gas behaves differently than Argon and is far more touchy. It is also far more expensive and expended faster per hour of runtime.

Mine requires 220V @ 10A
 
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diachi

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There are none. Even the smallest I've seen that I can think of all require 220v. The voltage drop is too large across the tube to sustain the arc at 120V. Krypton gas behaves differently than Argon and is far more touchy. It is also far more expensive and expended faster per hour of runtime.

Mine requires 220V @ 10A
IIRC the voltage difference between a tube with Ar fill and a tube with Ar/Kr fill isn't that large. It's just that even the small Ar/Kr tubes out there are still fairly large/long (relative to something like a JDSU 2211/4), so the voltage drop is always higher than you'd see with a small air cooled Ar-ion.

But yes, I haven't seen any that run on 120V either.

I have seen people run them off of two 15A 120V circuits (On the same phase of course) with a 120V-220V transformer. If you have a 30A 120V circuit somewhere you could run off of that with a transformer thrown in.
 

ultimatekaiser

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Nah krypton has different run characteristcs than argon. The operating voltage is similar, but the starting and voltage drops are higher. An example would be the 543/643. They are pretty much identical. The only difference is the gas fill. the 543 doesnt require 220. the 643 version has an additional set of starting components and a different setup inside the supply to accomodate the krypton.

Krypton gas is far more finicky than argon. Thats why you almost never see them, let alone working. Everything has to be perfect with them to work right. Theyre more expensive, and have much shorter lifetimes.

You can indeed use dual 120V taps to make up for that if there is enough available current. But most houses are rated 15A, but can handle closer to 18, so running it at higher powers will blow the breaker potentially if you use a step up solution. Depends on your home. Ive done both but they're still a pain.

Point is, none work on 120 inherently. Ive never seen one that can run on 120VAC. Power required for stability is just too high. Running it on a marginal source is bad for the tube and is unsafe for the user.
 
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diachi

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Nah krypton has different run characteristcs than argon. The operating voltage is similar, but the starting and voltage drops are higher. An example would be the 543/643. They are pretty much identical. The only difference is the gas fill. the 543 doesnt require 220. the 643 version has an additional set of starting components and a different setup inside the supply to accomodate the krypton.

Krypton gas is far more finicky than argon. Thats why you almost never see them, let alone working. Everything has to be perfect with them to work right. Theyre more expensive, and have much shorter lifetimes.

You can indeed use dual 120V taps to make up for that if there is enough available current. But most houses are rated 15A, but can handle closer to 18, so running it at higher powers will blow the breaker potentially if you use a step up solution. Depends on your home. Ive done both but they're still a pain.

Point is, none work on 120 inherently. Ive never seen one that can run on 120VAC. Power required for stability is just too high. Running it on a marginal source is bad for the tube and is unsafe for the user.

Thanks for clarifying!

Yep, North American circuits are usually 15A, hence why I said run it off of two circuits, this giving a total possible current of 30A, 15A from each circuit. But that's definitely not the best way to do it. Best just to provide the correct power from the get-go. :)
 

ultimatekaiser

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Yes. Especially as if you're taking it off of two sources they may not exactly match up perfectly, nor stay that way. AC can fluctuate- which can mess with the supply, and cause more noise and stress in the components etc. It is definitely not a good permanent solution. It'd probably be acceptable for a short run or a test but I wouldn't consistently run it that way.

On the other hand a step up transformer is of course more easy and practical to pull off, it has its own drawbacks.

The main purpose of my post was to say no 120V tubes exist that I've ever seen.

Though on the subject-krypton changes the dynamics of the gas in the tube quite a bit. The structure of a krypton tube is very similar, but has some changes. A lot of krypton tubes have larger gas returns, gas ballasts added, and other such things added to keep the gas flow and thermal dynamics good. Argon doesn't care as much. Actually used to be a pretty common problem for some kryptons to try to ignite down the gas return instead of the bore. very careful design is necessary to get them to be happy.
 




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