Re: neon conections

            Re: neon conections
            Wed, 09 Apr 1997 18:35:13 -0700
            Bert Hickman <bert.hickman-at-aquila-dot-com>
            Stoneridge Engineering
            Tesla List <tesla-at-pupman-dot-com>

Tesla List wrote:
> Subject:
>         neon conections
>   Date:
>         Tue, 8 Apr 1997 21:19:34 -0600 (CST)
>   From:
>         Jorge <al263636-at-academ02.sal.itesm.mx>
>     To:
>         Tesla List <tesla-at-poodle.pupman-dot-com>
> Greetings from Mexico !
>         Im making a 900 watt Tesla Coil, I`ve already finished my poly
>         cap. wich by the way was a real job, the thickest piece of poly
>         I could get here was .011 mils thick so I had to had 8 layers
>         of the plastic to get .088 mils wich I think is enough.
>         Now im concentrating on the neon`s, I got 3 of them from a neon
>         sign shop one was good the other two where way to burned out and
>         some of the secondarys where damaged I`ll possibly be able to
>         make one good from both. Both units are 15,000, 30ma so to get
>         15,000 60ma I have to put them in parallel right. How about the
>         primary`s of the neons, do they have to be in parallel too ??
>         Also when I was rebuilding one of the neons, on the shunts, do
>         these have to touch the core, or can they be insulated from it
> ??
>         Thanks in advance !
>         Jorge F.


Congratulations - looks like you're on your way to making a nice coil!
Neon secondaries should always be of the same voltage, and should always
be connected in parallel. It is also better to use the same output
current rating on each to provide better current sharing between

Most transformers in the USA use 120 volt primaries, although other
voltages are available (240 and 277 volts). The following applies to
common 120 volt transformers:
As long as you have them phased properly, you can run all the primaries
in parallel and run them off a 120 volt variac (preferred), or combine
_matched pairs_ of transformers in series to operate off a 240 volt
variac (not recommended). If you DO need to connect pairs in series, the
matched pairs should be from the same manufacturer and same model. This
is very important, since a pair of unmatched transformers will cause
unequal voltage sharing, and will overvolt the overstressed one. Even
with matched pairs, this can often occur due to simple manufacturing
variations and differences in current limiting behavior - this is why
the series configuration is not recommended. 

The magnetic shunts should touch the main core to insure a good magnetic

Safe coilin' to you, Jorge!

-- Bert H --