Re: Avalon

["Jim Lux" <jimlux-at-jpl.nasa.gov> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

> Can the building frame itself (the steel superstructure) be used as an 
> isolated RF Ground seperate from the main building electrical ground?

It's unlikely that the building frame is actually isolated from real ground
(not like the bldg is sitting up on post insulators, eh?) Furthermore, I'll
bet that for lightning safety, as well as other reasons, the frame is
actually bonded to ground rods (I don't know if they used UFER grounds 40
years ago).


> 
> This entire building will be remodeled as a dedicated use, strictly HV 
> experimentation and research. What types of things should we be thinking 
> about in the early phases of design? If you could make your dream Tesla 
> workshop, what would you have? Electrical service? Would it be preferable
to 
> have a 14.4KV feed direct inside the building? (There is a pad
transformer 
> RIGHT next to it with a 14.4KV primary.) My thoughts are to bring it in
at 
> LV (480VAC) to make switching and voltage regulation easier in the power 
> supply. Can you imagine a 15KV variac?.....ARGH!

As a start, you should invest a few hundred bucks in some books on HV
engineering which spend some time talking about HV lab and substation
design.  They give a lot of attention to grounding grids, power
distribution, clearances, structural issues, etc. Basically, if you look
for books with the title "High Voltage Engineering" you'll find useful
stuff.  Naidu and Kamaraju has a whole chapter on test labs.  The ground
requirements for TC's are very similar to those for impulse testing.

There ARE 15 kV autotransformers... They're big, they're called
tap-changers, and they tend to only adjust +/- 20% around the nominal
ratio.

I assume that by now you have a copy of the National Electrical Code and
the National Electrical Safety Code?  If not, get them and really
understand them.  They're somewhat tedious, but it will save you hours, if
not weeks, of time when arguing about whether something is covered in the
"code".  Lots of time, someone will say... you can't do that, it's against
code, and if you can point (in a non-confrontational way) to the specific
place where it IS permitted (or, at least, not prohibited), you're in great
shape.  What you are proposing to do is "unusual", and the first response
of most regulatory types will be to say "NO".
>