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how high is the voltage in the average neon transformer? Answered

I need to know because I may be using one as my power source for my Tesla-coil. 


Big electrical equipment, whatever it is, almost always comes with a plate or a sticker,  with the electrical specifications printed on it.

The attached picture is an example.  It is a neon sign transformer I found in my junk collection, and its little plate says its primary is rated at 120 VAC, and its secondary is rated at 9000 VAC at 25 mA.  Also notice that number 225 VA.  It is 9000 V multiplied by 25 mA.

I don't know how close this 9000V is to the "average" you are asking about. I am guessing any NST with a secondary in the range of 5000 to 15000 would work.


Nothin' man. It's stolen!

Actually I think I got it out of a dumpster, I think. Honestly I'm having trouble remembering where I got it from.

However, since you asked about cost, there is a market for used NSTs, on eBay. Uh... here:

For those people who are inclined to sell their old junk on eBay... I don't think I could bear to part with any of my old junk, including that transformer.

I went to a sign company and they very generously gave me a bunch
of used xfmrs they pulled out of service and were on a pallet awaiting
proper disposal.

The voltage of the average neon transformer is of no concern to you. What you are interested in is what the voltage of the one that you can get your hands on.


5 years ago

The smaller xfmrs are 7500 V  225 VA  30 ma,
the big xfmr is 15000 V   50 ma    60 Hz.



cool!!! I want a Tesla Coil so bad