Re: Earth leakage and SS Variac

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "David Sharpe by way of Terry Fritz <twftesla-at-qwest-dot-net>" <sccr4us-at-erols-dot-com>

Byron
Check the archives, a light dimmer type control was investigated earlier
this year
and on surface does not appear suitable for HV control.  I am working on a
true continuous power variac replacement, but it is a ways off from completion
and will be more complicated then a viarac (at least electronics wise).

Regards
Dave Sharpe, TCBOR
Chesterfield, VA

Tesla list wrote:

> Original poster: "Byron by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<byron-at-4zzzfm-dot-org.au>
>
> Hi, I'm new to this, and partway through trying to build a control box
> capable of preventing me from making a few stupid mistakes, like touching
> the primary side..
> The main way I have of doing this is with earth-leakage protection, the
> first beig a normal meter-box type ELD. The second a current detection
> from the centertaped earth the NSTs have. Has anyone played around with
> anything like this? Does the coil's spikes and other crap it puts on the
> lines cause false triggering?
>
> My other idea, was, instead of using a normal variac, wich seems anoying
> hard to find and expensive to buy, if it' a good idea to build a
> solid-state version, the design I currently have involves cutting the
> half-waves of the cycles at a point along the wave.
> (aka: http://www.zetetics-dot-com/bj/papers/phd/appxa.pdf (Second section
> down)
>
> Thoughs apresiated.
>
> (And the coils are cool! I have so been looking forward to building one
> for ages! And I have nearly everything I need! (Once I can convince some
> people that the safty conreols are good enough))
>
> --
> __
>   Triple Zed  102.1MHz                  Agitate, Educate, Organise
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