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Re: Neon life (and death)
From: Bert Hickman[SMTP:bert.hickman-at-aquila-dot-com]
Reply To: bert.hickman-at-aquila-dot-com
Sent: Thursday, October 30, 1997 2:07 AM
To: Tesla List
Subject: Re: Neon life (and death)
Tesla List wrote:
>
> From: ghunter-at-mail.enterprise-dot-net[SMTP:ghunter-at-mail.enterprise-dot-net]
> Sent: Wednesday, October 29, 1997 3:20 PM
> To: tesla-at-pupman-dot-com
> Subject: Neon life (and death)
>
> What's the typical lifespan of a neon TC power supply? One
> subscriber to the list has suggested that a pile of used neon
> transformers is good to have around, because they don't last very
> long. I find this most disturbing, as I own only ONE neon
> transformer, and it wasn't free. I've seen working luminous sign
> transformers in downtown New Orleans that appear to have been on
> continuous duty for decades. Obviously, neons are built to last. So
> why would a TC shorten the life of a neon so drastically? I'm aware
> of the need for output chokes, and mine will be protected with four
> (4) robust, home-made units (2 big air-cores, and 2 fat ferrite
> cores). I'm also including a safety gap. What more can I do?
> Series power resistors maybe?
>
> Greg
>
>
Greg,
A typical neon sign transformer spends virtually all its life looking at
a few thousand voltas of output once the conduction neon tube has driven
the transformer into current-limit mode. In TC use, the transformer
typically sees voltage spikes well above its rated peak open-circuit
voltage, plus RF that can make it back to the secondary windings. The
combination of these two causes corona, and results in the destruction
of inter-turn insulation, ultimately destroying the fine secondary
windings. If you're planning to do serious coiling, you'll need to
locate a source of cheap neons. If your REALLY serious, then you'll
migrate to a potential transformer or a pole pig...
Safe coilin' to you!
-- Bert --