From: "Tesla list" <tesla@xxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: Re: Very Confused On Grounding
Date: Sun, 15 May 2005 15:06:58 -0600
Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
Hi,
I don't think anyone has done it yet??? But maybe try running off a
computer UPS backup power supply. They go real cheap when the battery is
old and dead. You can hook a car battery to them, but be very careful
since the battery may "go live" to 120VAC potentials... This would also
make a coil portable... No worries about blowing AC line stuff then ;-))
They also make 12VDC to 120VDC inverters for RVs and campers...
Cheers,
Terry
At 01:37 PM 5/15/2005, you wrote:
Another thought that I had...if I use the RF ground for my NST case won't
there be tons of RF on the NST and NST internals? Wouldn't doing this
defete the purpose of the Terry Filter and possibly kill my NST? What if
I just use the RF ground for the safety gap, filter, strike rail, and
bottom of secondary? Not using mains ground at all. I just can't afford
anything to get damaged. It took me nearly 6 months to get me 12/30
Franceformer NST. Everything in the house is my parents and CANNOT get
damaged. Thanks
From: "Tesla list" <tesla@xxxxxxxxxx>
To: tesla@xxxxxxxxxx
Subject: Re: Very Confused On Grounding
Date: Sun, 15 May 2005 11:19:51 -0600
Original poster: Terry Fritz <teslalist@xxxxxxxxxxxxxxxxxxxxxxx>
Hi,
And in general, anything that can be hit by a streamer should be
grounded to the RF ground. If it is too far away to be hit, ground it
to the AC ground.
Cheers,
Terry
At 12:20 AM 5/15/2005, you wrote:
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