Re: Very Confused On Grounding

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Harold Weiss" <hweiss@xxxxxxxxxx>

Hi All,

I agree with Gerry on this.  I have everything at the coil grounded to RF 
ground, and everything at the controller at power ground.  The power cables 
running to the coil have power ground available in them, and I can run the 
coil on power ground if RF ground is unavailable.  The biggest thing to 
watch for is, NOT to have both grounds connected together at the same time. 
If they were, the RF ground could look as a better path and have major 
power on it.  On disconnection, you could have a hot connection and arcing.

David E Weiss

> Original poster: "Gerald  Reynolds" <gerryreynolds@xxxxxxxxxxxxx>
>
> Hi Terry,
>
> I still think it is best to connect the NST case, your filter, safety gap, 
> strike rail, and secondary base to RF ground.  The variac case and EMI 
> filter should be connected to mains safety ground.  RF on the NST case 
> will be common mode on the line input and the EMI filter should have a 
> common mode choke (or two) in it.  Personally, I dont want to take any 
> chance of a discharge resulting in transient current traveling down (or 
> up) the mains safety ground.  This could be catastrophic to any 
> electronics plugged into the mains, whether turned on or off.  Grounding 
> the coil system to mains safety ground, I believe, should only be 
> considered when the coil is operated inside where earth ground is not 
> easily available.  For this case, the coil should be used with a 
> counterpoise, the power kept low, and great care be taken as to what the 
> streamers can strike.
>
> Gerry
>
> > Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
> >
> > At 04:02 PM 5/13/2005, you wrote:
> > > In the Terry Filter he shows one side be grounded to RF (spark gap side) 
> > > and the other side of the filter be tied to the NST case.  Wouldn't this 
> > > cause major RF on the NST case and maybe inducing into house lines?
> >
> > Interesting thought...  I was thinking the NST case might be hit by 
> > streamers in which case it would be best to have it tied to the RF 
> > ground. "Maybe" there are situations where the case would be best tied to 
> > the AC. But I normally just use the AC ground for safety since it is 
> > terrible and conducting RF.
> >
> > All my coils have MOVs and dual-stage line filters on the AC line too :-) 
> > So maybe if you are worried, you would want to do that as well.  That 
> > stuff can be far back at say the AC power outlet.  Mine are inside the 
> > variac controller.
> >
> > Cheers,
> >
> >         Terry