X-Ray Transformer Issue

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Sam_Samida-Pugh
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X-Ray Transformer Issue

Post by Sam_Samida-Pugh » Thu Nov 30, 2017 10:26 pm

Unfortunately, my high voltage X-Ray transformer has recently suffered some internal arcing in one of the secondary coils and no longer puts out its full voltage rating. This normally wouldn't have been too big of a problem as the other secondary coil is still in working order and reaching 30kV DC would normally still be feasible. However, there is also an issue in regard to current draw. Even with a primary ballast, the transformer pulls 9.3 amps at only 30v input. I am somewhat confused as to why this is happening and would appreciate any insight into this problem. Thanks.

John Futter
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Re: X-Ray Transformer Issue

Post by John Futter » Fri Dec 01, 2017 2:54 am

Sam
You have some shorted turns
which in a transformer is a big no no as it kills the inductance hence the current goes up dramatically
you now have an expensive paper weight unless you can unwind / cut off the faulty winding

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Dennis P Brown
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Re: X-Ray Transformer Issue

Post by Dennis P Brown » Fri Dec 01, 2017 9:27 am

First, I am so very sorry to hear this - besides the cost of those x-formers, they are extremely difficult to obtain. I hope the bad wires can be located and removed without major recourse like a nearly full break down of the unit/windings.

I use forced air cooling on my x-former but it was designed for air use only; I assume your's is in oil? If so, was there a bubble/air still in the windings, maybe?

Sam_Samida-Pugh
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Re: X-Ray Transformer Issue

Post by Sam_Samida-Pugh » Fri Dec 01, 2017 6:17 pm

I was keeping the transformer in oil; but, instead of pulling a vacuum, I just let it soak for a couple months hoping it would do the job to remove any bubbles. Unfortunately, it seems that there was still some air in the windings which is what caused the short. I will be sure to pull a vacuum on the oil instead for next time.

Regardless, I am going to attempt to remove the destroyed coil and hope it fixes the problem.

Sam_Samida-Pugh
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Re: X-Ray Transformer Issue

Post by Sam_Samida-Pugh » Sat Dec 02, 2017 2:06 am

Some good news.

Today I attempted to remove the faulty coil from the transformer and was successful. Shortly after this, I tested the transformer and the other secondary still retains it's 350:1-volt ratio; also, the primary circuit no longer pulls massive current.

I am hoping that this transformer will still be functional for fusion in the 20kV range, I will be conducting further tests soon.
Transformer in progress.jpg
Coil being removed
Transformer removed coil.jpg
Transformer with the coil removed
Faulty coil scrap.jpg
Faulty coil scrap

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Richard Hull
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Re: X-Ray Transformer Issue

Post by Richard Hull » Sat Dec 02, 2017 4:40 am

In my Tesla coiling days, I removed many a shorted secondary half from de-potted neon transformers to restore them to functionality at 1/2 voltage. It worked every time.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
Retired now...Doing only what I want and not what I should...every day is a saturday.

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Dennis P Brown
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Re: X-Ray Transformer Issue

Post by Dennis P Brown » Sat Dec 02, 2017 11:04 am

Using a smaller chamber - specifically a vacuum four-way cross - someone here not too long ago easily achieved detectable fusion using just under 20 kV (of course their power was still in the correct range and if memory serves, about 20 ma.) So, your x-former should be able to do that. Very glad it is still usable even if only half voltage.

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