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Re: Case Ground.

Tesla List wrote:
> 
> Subscriber: daniel_hess-at-VNET.IBM.COM Sun Jan 12 22:11:56 1997
> Date: Sun, 12 Jan 97 11:14:53 CST
> From: daniel_hess-at-VNET.IBM.COM
> To: tesla-at-pupman-dot-com
> Subject: Case Ground.
> 
>  > What about the case of my neon transformers, (to house/water pipe
>  > ground)? They're connected center tap to the secondaries and therefore
>  > part of the primary.
>  >
>  > Thanks, Daniel
> 
>  Daniel,
> 
>  There are a few reasons to tie the case to at least the RF ground:
> 
> Bert; I have my neons and all of my controls, (variacs, cb's, meters,
> and so on,) mounted in a large metal cabinet. The frame of this cabinet
> as well as all of it's componets, (variacs, neons...) are all grounded
> via the circut breaker panel supply, which besides the power company
> supplied neutral-ground, is also tied to my plumbing. I've done this
> firstly for my own protection and secondly for the protection of the
> equipment.
> 
> If I tie the case of my neons, (which is already grounded to house,)
> to my rf ground, this brings everybody together. Isn't this configuration
> a no-no and wouldn't that defeat the purpose of having a dedicated
> rf ground? If I disconnect my neon case from my house ground and connect
> it ONLY to my rf ground, it seems that there would exist a potentially,
> (pun intended,) hazardous condition to myself. But if I understand your reply
> correctly, you're suggesting to do just that; Tie house and rf grounds
> together?
> 
> Thanks, Daniel Hess

Daniel,

If you've already got your neons grounded because of the way you've
mounted them in the metal cabinet, then DON'T tie the RF ground to the
AC ground. Normally, the cases of the neons should be allowed to float
from AC ground so that you CAN tie them to a separate RF ground. This is
consistent with earlier guidelines that Richard Quick had proposed, and
they seem to make sense. 

I'm not aware of any comparative testing between the two grounding
methods, but I'd _suspect_ the isolated neon case tied to RF ground
would be the lower conducted RFI approach. 

-- Bert --