"Ole Bob", It's true - the statements "do compute". Neon sign transformers (NST) are designed to have a voltage high enough to ionize the neon, which takes just a brief time. Once the neon tube conducts, the voltage drops down considerably. The current is limited by magnetic shunts. The best way to "kill" a NST is to just plug it in with no load to lower the output voltage. NSTs are not at all like plate transformers.
I belong to the Tesla list, and NSTs are the most common high voltage power source for Tesla coils. The constant complaint is that NSTs burn out quickly unless safety spark gaps are used to limit their output voltage. Many are the anguished reports of zapped NSTs! The failure mechanism is the potting material gradually breaks down, arcs, and a carbon track forms. These transformers can sometimes be salvaged by melting out the potting compound and refilling with vasoline or transformer oil. Very messy, time consuming job! So yes, get a 15KV transformer and run it on 70 volts input to extend the transformer life. A shorted NST will get hot, but I have not heard of them failing nearly as frequently as running them open circuit. --Steve ----- Original Message ----- From: Robert L. Berger To: [email protected] Sent: Wednesday, November 08, 2000 12:36 PM Subject: Re: CS>HVAC Colloidal Silver Generator Construction <snip>, If you run a neon sign transformer way above it's design voltage of abou 70% of it's nameplate voltage, it will fail from insulation failure, and if you run it for long periods below it it will fail from overheating. Load must be varied to maintain the proper output voltage of the transformer, or early failure will likely result. I would like to see the source of this data!! While I have never designed a transformer of neon sign service, I have designed transformers for the old tube type ham radio transmitters, as well as pulse welding transformers, and your statements do not compute. "Ole Bob"
